Image processing system

Abstract

Provided is a display device or an electronic apparatus with low power consumption. Provided is an image processing system that can reduce the quantity of communication data. This image processing system has a display unit, an input unit, a calculation unit, and an image processing unit. The input unit has a function of acquiring location information regarding an instructing operation that is performed by a user. The calculation unit has a function of determining a first region and a second region on the basis of the location information. The image processing unit has a function of performing image processing of a section of a first image and thereby generating a second image, said section corresponding to the first region. The display unit has a function of displaying the second image.

Description

Image Processing System

[0001] FIELD OF THE INVENTION One aspect of the present invention relates to an electronic device. One aspect of the present invention relates to a method for driving an electronic device. One aspect of the present invention relates to a display device. One aspect of the present invention relates to a method for driving a display device. One aspect of the present invention relates to a program.

[0002] Note that one embodiment of the present invention is not limited to the above technical field. Examples of the technical field of one embodiment of the present invention disclosed in this specification and the like include semiconductor devices, display devices, light-emitting devices, power storage devices, memory devices, electronic devices, lighting devices, input devices, input / output devices, driving methods thereof, and manufacturing methods thereof. A semiconductor device refers to any device that can function by utilizing semiconductor characteristics.

[0003] In recent years, information terminal devices such as mobile phones such as smartphones, tablet information terminals, and notebook PCs (personal computers) have become widely used. These terminal devices are equipped with a screen for displaying images and input means such as a touch panel, a mouse, or a controller.

[0004] For example, products that use capacitive touch sensors in their touch panels are becoming widespread. Patent Document 1 discloses a touch panel configuration in which both an organic EL element and an organic photodiode are arranged in the display unit, and fingerprint authentication is possible on the display unit.

[0005] International Publication No. 2020 / 053692

[0006] An object of one embodiment of the present invention is to provide a display device or electronic device with low power consumption.Another object is to provide an image processing system, a display device, or an electronic device that can reduce the amount of communication data.Another object is to provide a system using an electronic device that does not require high computing performance.Another object is to provide an image processing system, a display device, or an electronic device that reduces power consumption without causing a sense of discomfort to a user.

[0007] An object of one embodiment of the present invention is to provide an image processing system having a novel configuration, a display device having a novel configuration, or an electronic device having a novel configuration. Alternatively, an object of one embodiment of the present invention is to provide a method for driving a display device having a novel configuration or a method for driving an electronic device having a novel configuration. An object of one embodiment of the present invention is to at least alleviate at least one of the problems of the prior art.

[0008] Note that the description of these problems does not preclude the existence of other problems. Note that one embodiment of the present invention does not necessarily solve all of these problems. Note that problems other than these can be extracted from the description of the specification, drawings, claims, etc.

[0009] One aspect of the present invention is an image processing system having a display unit, an input unit, a calculation unit, and an image processing unit. The input unit has a function of acquiring position information of a user's instruction operation. The calculation unit has a function of determining a first region and a second region based on the position information. The image processing unit has a function of generating a second image by performing image processing on a portion of a first image corresponding to the first region. The display unit has a function of displaying the second image.

[0010] In the above, it is preferable that the device further includes a communication unit having a function of communicating with a server. In this case, it is preferable that the image processing unit is provided in the server. Alternatively, it is preferable that the image processing unit and the calculation unit are provided in the server.

[0011] In any of the above, it is preferable that the image processing is processing for lowering the resolution of the first region compared to the second region.

[0012] In any of the above, it is preferable that the image processing is processing for lowering the frequency of the first region more than that of the second region.

[0013] In any of the above, it is preferable that the image processing is processing for lowering the gradation of the first region compared to the second region.

[0014] In any of the above, the input unit preferably has a touch sensor. In this case, the touch sensor more preferably has a capacitance sensor or an organic light diode.

[0015] In any of the above, it is preferable that the first area is an area in which a moving image is displayed, and the second area is an area in which a moving image or a still image with slower movement than that in the first area is displayed.

[0016] In any of the above, it is preferable that the second area is an area including coordinates designated by the user, and the first area is an area surrounding the second area.

[0017] In any of the above, it is preferable that the display unit has a resolution of 50 ppi or more and 1500 ppi or less.

[0018] According to one embodiment of the present invention, a display device or electronic device with low power consumption can be provided. Alternatively, a display device or electronic device that can reduce the amount of communication data can be provided. Alternatively, a system using an electronic device that does not require high computing performance can be provided. Alternatively, a display device or electronic device that reduces power consumption without causing a sense of discomfort to a user can be provided.

[0019] According to one aspect of the present invention, it is possible to provide an image processing system having a novel configuration, a display device having a novel configuration, or an electronic device having a novel configuration. Alternatively, it is possible to provide a method for driving a display device having a novel configuration, or a method for driving an electronic device having a novel configuration. According to one aspect of the present invention, it is possible to at least alleviate at least one of the problems of the prior art.

[0020] Note that the description of these effects does not preclude the existence of other effects. Note that one embodiment of the present invention does not necessarily have all of these effects. Note that effects other than these can be extracted from the description in the specification, drawings, claims, etc.

[0021] FIGS. 1A and 1B are diagrams showing an example of the configuration of an electronic device, and FIG. 1C is a diagram showing an example of the configuration of a system. FIG. 2 is a diagram showing an example of the configuration of the system. FIG. 3 is a flowchart showing the operation of the system. FIGS. 4A and 4B are diagrams showing an example of the operation. FIGS. 5A and 5B are diagrams showing an example of the operation. FIGS. 6A to 6D are diagrams showing an example of the operation. FIGS. 7A to 7D are diagrams showing an example of the operation. FIGS. 8A and 8B are diagrams showing an example of the operation. FIGS. 9A to 9C are diagrams showing an example of the operation. FIGS. 10A and 10B are diagrams showing an example of the configuration of a display device. FIG. 11 is a diagram showing an example of the configuration of a display device. FIG. 12 is a diagram showing an example of the configuration of a display device. FIGS. 13A to 13C are diagrams showing an example of the configuration of a display device. FIGS. 14A to 14F are diagrams showing an example of the configuration of a pixel. FIG. 15 is a diagram showing an example of the configuration of a display device. FIGS. 16A and 16B are diagrams showing an example of the configuration of a display device. FIG. 17 is a diagram showing an example of the configuration of a display device. FIGS. 18A to 18F are diagrams showing an example of the configuration of a light-emitting device. 19A to 19C are diagrams showing configuration examples of a light-emitting device. FIGS. 20A and 20B are diagrams showing configuration examples of a light-receiving device. FIGS. 20C to 20E are diagrams showing configuration examples of a display device. FIG. 21A is a block diagram showing an example of a display panel. FIGS. 21B to 21D are diagrams showing an example of a pixel circuit. FIGS. 22A to 22D are diagrams showing an example of a transistor. FIGS. 23A to 23F are diagrams showing configuration examples of an electronic device. FIGS. 24A to 24G are diagrams showing configuration examples of an electronic device.

[0022] Hereinafter, embodiments will be described with reference to the drawings. However, it will be readily understood by those skilled in the art that the embodiments can be implemented in many different ways and that various changes in form and details can be made without departing from the spirit and scope of the present invention. Therefore, the present invention should not be interpreted as being limited to the following description of the embodiments.

[0023] In the configuration of the invention described below, the same parts or parts having similar functions are denoted by the same reference numerals in different drawings, and repeated explanations thereof will be omitted. Furthermore, when referring to similar functions, the same hatching pattern may be used and no particular reference numeral may be assigned.

[0024] In the drawings described in this specification, the size of each component, the thickness of a layer, or an area may be exaggerated for clarity, and therefore, the drawings are not necessarily limited to the scale.

[0025] In this specification, ordinal numbers such as "first" and "second" are used to avoid confusion of components and do not limit the number.

[0026] In the following description, expressions indicating directions such as "up" and "down" are basically used in accordance with the directions in the drawings. However, for ease of explanation, the directions indicated by "up" or "down" in the specification may not match those in the drawings. For example, when explaining the stacking order (or formation order) of a laminate, etc., even if the surface on which the laminate is provided in the drawing (such as the surface to be formed, the supporting surface, the adhesive surface, or the flat surface) is located above the laminate, the direction toward the surface may be expressed as "down" and the opposite direction as "up."

[0027] Furthermore, in this specification and the like, the terms "film" and "layer" are interchangeable. For example, the terms "conductive layer" and "insulating layer" may be interchangeable with the terms "conductive film" and "insulating film."

[0028] In this specification and the like, a display panel, which is one aspect of a display device, has a function of displaying (outputting) an image or the like on a display surface, and therefore the display panel is one aspect of an output device.

[0029] In addition, in this specification, a display panel having a connector such as an FPC (Flexible Printed Circuit) or a TCP (Tape Carrier Package) attached to the substrate, or a display panel having an IC mounted on the substrate using a COG (Chip On Glass) method or the like, may be referred to as a display panel module, a display module, or simply a display panel.

[0030] In this specification and the like, a touch panel, which is one aspect of a display device, has a function of displaying an image or the like on a display surface and a function as a touch sensor that detects that a detectable object such as a finger or a stylus touches, presses, or approaches the display surface. Thus, the touch panel is one aspect of an input / output device.

[0031] A touch panel can also be called, for example, a display panel (or display device) with a touch sensor or a display panel (or display device) with a touch sensor function. A touch panel can have a configuration including a display panel and a touch sensor panel. Alternatively, the touch panel can have a touch sensor function inside or on the surface of the display panel.

[0032] In addition, in this specification and the like, a touch panel substrate on which a connector or an IC is mounted may be referred to as a touch panel module, a display module, or simply a touch panel.

[0033] Embodiment 1 In this embodiment, an image processing system according to one embodiment of the present invention, and an electronic device, a display device, a server, and the like that can be used in the image processing system will be described.

[0034] The image processing system of one embodiment of the present invention can reduce power consumption required for image display by performing image processing in response to user input. Furthermore, since part of the processing is performed on a server, the electronic device used by the user does not need to perform advanced arithmetic processing, and therefore the image processing system can be implemented even in inexpensive electronic devices.

[0035] The image processing system of one embodiment of the present invention can be applied to, for example, electronic devices having a touch panel. Such electronic devices can switch or scroll screens in response to a user's touch operation. In addition to the touch panel, electronic devices using various input means (also referred to as user interfaces) such as a digitizer, a mouse, a touchpad, a controller, and a keyboard can also perform similar operations.

[0036] When a screen changes in response to a user's operation, the image displayed on the screen often contains a mixture of moving parts (called moving parts) and non-moving parts (still image parts). Here, the faster the moving parts are, the harder it is for the user to perceive the image resolution. Therefore, lowering the image resolution of the moving parts does not cause discomfort to the user. Therefore, by performing image processing to lower the resolution of the moving parts and displaying the still image parts at their original resolution, the overall image data volume can be reduced. Furthermore, the power consumption required for image display and the amount of calculation required for image processing (rendering, etc.) can be reduced.

[0037] The image processing system according to one embodiment of the present invention can divide an entire image into two or more regions in response to a user's operation (instruction operation) and the image being displayed, and perform image processing for each region. Examples of image processing include reducing the resolution, reducing the frequency, and reducing the gradation (brightness).

[0038] The image processing can also be performed based on the user's gaze point. For example, image processing can be performed so that the resolution, frequency, or gradation (brightness) is highest at and near the gaze point, and the resolution decreases as the distance from the gaze point increases.

[0039] When performing image processing based on the user's gaze point, it is preferable to estimate the gaze point based on the user's pointing position and determine the area to be processed. For example, the area including the pointing position can be set as the area including the gaze point, and image processing can be performed such that the resolution, frequency, or gradation (brightness) decreases with increasing distance from the pointing position.

[0040] A more specific example will be described below with reference to the drawings.

[0041] 1A and 1B show external views of an electronic device 10. Fig. 1A shows the front side of the electronic device 10, and Fig. 1B shows the back side.

[0042] The electronic device 10 is a portable information terminal that can be used as a smartphone or a tablet terminal. The electronic device 10 has a display unit 11, a calculation unit 12, an image processing unit 13, a communication unit 14, etc., which are provided in a housing 20. Also, in Figures 1A and 1B, an illuminance sensor 31, a camera 32, a speaker 33, a microphone 34, a camera 35, etc., which the electronic device 10 has are shown. However, the electronic device 10 is not limited to these, and may have other components.

[0043] 1C is a block diagram showing an example of a hardware configuration of a portion of electronic device 10. Electronic device 10 includes a display unit 11, a calculation unit 12, an image processing unit 13, a communication unit 14, a sensor unit 15, an imaging unit 16, and an audio control unit 17. Each configuration (component) is electrically connected to one another via a bus line.

[0044] In the following, for ease of explanation, when there is no need to distinguish between components other than the calculation unit 12 included in the electronic device 10, each component may be referred to as a component.

[0045] The display unit 11 has a display device 21 and an input device 22. The display unit 11 also has a drive unit 23 for controlling the drive of the display device 21 and a drive unit 24 for controlling the drive of the input device 22. The drive unit 24 has a function of generating and outputting position information from a signal output from the input device 22. The display device 21 has a function of displaying an image. The input device 22 has a function of a touch sensor. The display unit 11 can also be called a touch panel or a display device with a touch function.

[0046] The display device 21 has a plurality of pixel circuits arranged periodically. One or more display elements are connected to one pixel circuit. Examples of the display elements that can be used include liquid crystal elements, organic EL elements, inorganic EL elements, LED elements, microcapsules, electrophoretic elements, electrowetting elements, electrofluidic elements, electrochromic elements, and MEMS elements. It is particularly preferable to use organic EL elements, LED elements, or liquid crystal elements.

[0047] The higher the pixel density (also referred to as resolution) of the display device 21, the higher the image resolution that can be displayed when the display unit 11 has the same size. The pixel density (resolution) of the display device 21 is preferably 50 ppi or more and 1500 ppi or less, preferably 80 ppi or more and 1200 ppi or less, and more preferably 100 ppi or more and 1000 ppi or less. Note that the resolution of the display device 21 is not limited to this, and display devices 21 with various resolutions can be used depending on the application of the electronic device 10 and the size of the display unit 11.

[0048] The input device 22 has a function of acquiring a position indicated by a user and outputting the position information to the calculation unit 12 .

[0049] The input device 22 is not limited to a touch sensor, and the various input means described above can be used. When a sensor other than a touch sensor is used, the input device 22 may be provided independently of the display unit 11 without being included in the display unit 11.

[0050] The calculation unit 12 can function as, for example, a central processing unit (CPU) and has a function of controlling each component.

[0051] The calculation unit 12 can also perform various calculation processes. For example, based on position information input from the input device 22, the calculation unit 12 can perform calculations related to dividing an area into areas where image processing is performed and areas where image processing is not performed.

[0052] The image processing unit 13 is controlled by the calculation unit 12 and has a function of performing image processing. The image processing unit 13 performs image processing on each of the multiple regions divided by the calculation unit 12, for example, and generates an image to be displayed on the display unit 11. It is preferable to use a processor such as a GPU (Graphics Processing Unit) as the image processing unit 13. Note that although the image processing unit 13 is shown here as a component separate from the calculation unit 12, the image processing unit 13 and the calculation unit 12 may share the same hardware.

[0053] The communication unit 14 is controlled by the calculation unit 12 and has a function of performing wireless or wired communication. The communication unit 14 can communicate with a server 80 provided outside the electronic device 10.

[0054] Here, various sensors included in the electronic device 10 are collectively referred to as a sensor unit 15. The sensor unit 15 includes, for example, an acceleration sensor 36 in addition to the illuminance sensor 31 shown in FIG. 1A. Various sensors can be used in the sensor unit 15 depending on the configuration and required functions of the electronic device 10. For example, in addition to the above, various sensors such as a fingerprint sensor, a temperature sensor, a humidity sensor, an electroencephalogram sensor, a blood pressure sensor, a geomagnetic sensor, and a GPS can be used.

[0055] The plurality of imaging devices included in the electronic device 10 are collectively shown as an imaging unit 16. The imaging unit 16 includes, for example, the camera 32 and the camera 35 shown in FIG.

[0056] The electronic device 10 may also have a function of estimating the user's gaze point using the imaging unit 16. For example, the camera 32 acquires information about the user's face and information about the distance between the electronic device 10 and the user. The calculation unit 12 can estimate the user's gaze point on the screen of the display unit 11 from the positions of the two eyeballs that can be acquired from the information about the user's face, the distance between the electronic device 10 and the user, and the like.

[0057] The computing unit 12 may also have a function for performing face authentication. For example, the camera 32 may capture an image of the user's face, and the computing unit 12 may perform face authentication using feature points obtained from the image. In particular, when the camera 32 is used for face authentication, it is preferable to use a camera that is sensitive to not only visible light but also infrared light, or to have a configuration that includes both a camera that is sensitive to visible light and a camera that is sensitive to infrared light.

[0058] 1B shows an example in which two cameras 35 are provided on the rear surface of the electronic device 10. However, by arranging multiple cameras with different angles of view, various focal lengths from wide angle to telephoto can be accommodated. Furthermore, by using images captured simultaneously by multiple cameras, it is possible to change the focus and depth of field using the captured images. Furthermore, a camera sensitive to infrared or ultraviolet light may be provided.

[0059] The audio control unit 17 has a function of controlling audio output and audio input. The audio control unit 17 has, for example, the speaker 33 and microphone 34 shown in FIG. 1A. In addition to the speaker, an internal speaker such as a bone conduction speaker may be used as the audio output device included in the audio control unit 17. Furthermore, audio data may be output wirelessly or via a wired connection to earphones, headphones, an external speaker, or the like.

[0060] Signals are transmitted between the calculation unit 12 and each component via a bus line. The calculation unit 12 has functions such as processing signals input from each component connected via the bus line and generating signals to be output to each component, and can comprehensively control each component connected to the bus line.

[0061] Note that a transistor having an oxide semiconductor in a channel formation region and thus an extremely low off-state current can also be used in the ICs, etc., of the computing unit 12 or other components. Because the off-state current of the transistor is extremely low, the transistor can be used as a switch for retaining charge (data) flowing into a capacitor functioning as a memory element, thereby ensuring a long data retention period. By utilizing this characteristic in a register or cache memory of the computing unit 12 or the image processing unit 13, the computing unit 12, etc. is operated only when necessary, and information from the previous processing is saved in the memory element at other times, thereby enabling normally-off computing, in which the power supply to the computing unit 12, etc. is shut off. This enables low power consumption of the electronic device 10.

[0062] The calculation unit 12 performs various data processing and program control by interpreting and executing instructions from various programs using a processor. The programs that can be executed by the processor may be stored in a memory area of ​​the processor or in a separate storage unit.

[0063] In addition to a CPU, other microprocessors such as a DSP (Digital Signal Processor) and a GPU (Graphics Processing Unit) can be used alone or in combination as the calculation unit 12 and the image processing unit 13. Furthermore, these microprocessors may be realized by a PLD (Programmable Logic Device) such as an FPGA (Field Programmable Gate Array) or an FPAA (Field Programmable Analog Array).

[0064] The calculation unit 12 and the image processing unit 13 may each have a main memory. The main memory may include a volatile memory such as a RAM (Random Access Memory) or a non-volatile memory such as a ROM (Read Only Memory).

[0065] The RAM provided in the main memory may be, for example, a dynamic random access memory (DRAM), and a virtual memory space is allocated to it and used as a working space for the calculation unit 12 or the image processing unit 13. The operating system, application programs, program modules, program data, etc. stored in the storage unit are loaded into the RAM for execution. These data, programs, program modules, etc. loaded into the RAM are directly accessed and operated by the calculation unit 12 or the image processing unit 13.

[0066] On the other hand, the ROM can store a BIOS (Basic Input / Output System), which does not require rewriting, firmware, etc. As the ROM, a mask ROM, an OTPROM (One Time Programmable Read Only Memory), an EPROM (Erasable Programmable Read Only Memory), etc. can be used. Examples of EPROMs include UV-EPROMs (Ultra-Violet Erasable Programmable Read Only Memories), which allow stored data to be erased by exposure to ultraviolet light, EEPROMs (Electrically Erasable Programmable Read Only Memories), and flash memories.

[0067] Furthermore, it is preferable that the image processing unit 13 has a processor specialized for parallel calculations rather than a CPU. For example, it is preferable that the image processing unit 13 has a processor having a large number (tens to hundreds) of processor cores capable of parallel processing, such as a GPU, a TPU (Tensor Processing Unit), or an NPU (Neural Processing Unit). This allows the image processing unit 13 to perform calculations, particularly those related to neural networks, at high speed.

[0068] The communication unit 14 can wirelessly exchange data with external communication devices. For example, the communication unit 14 can communicate via an antenna. The communication means (communication method) of the communication unit 14 can be, for example, a computer network such as the Internet, an intranet, an extranet, a personal area network (PAN), a local area network (LAN), a campus area network (CAN), a metropolitan area network (MAN), a wide area network (WAN), or a global area network (GAN), which is the foundation of the World Wide Web (WWW). When performing wireless communication, communication standards such as the third generation mobile communication system (3G), the fourth generation mobile communication system (4G), and the fifth generation mobile communication system (5G), or specifications standardized by the IEEE such as Wi-Fi (registered trademark) and Bluetooth (registered trademark), can be used as communication protocols or communication technologies.

[0069] 2 shows an example in which the configuration is partially different from that described above. In addition, a block diagram of a server 80 is also shown in FIG.

[0070] The server 80 includes a calculation unit 81 , an image processing unit 82 , and a communication unit 83 .

[0071] For the calculation unit 81, the description of the calculation unit 12 can be referred to. Here, an example is shown in which the image processing unit 82 is included in the calculation unit 81. In other words, the calculation unit 81 can execute image processing.

[0072] 2 does not include the image processing unit 13. The calculations for image processing that were previously performed by the image processing unit 13 can be executed by the image processing unit 82 of the server 80 via the communication unit 14 and the communication unit 83.

[0073] In this way, by connecting the electronic device 10 and the server 80 via a communication unit and executing part of the arithmetic processing on the server 80 side, the electronic device 10 is not required to have high computing power, and therefore the components can be simplified. This not only reduces the cost of the electronic device 10, but also makes it easier to make the electronic device 10 lighter, smaller, and thinner. A system in which much of the processing is performed on the server in this way and the terminal configuration can be simplified can be called a thin client system.

[0074] Furthermore, part of the processing executed by the calculation unit 12 can also be executed by the calculation unit 81 of the server 80. For example, the processing related to the classification described above can be executed on the server 80 side.

[0075] In recent years, thin clients, which perform the main processing on the server side and only perform limited processing on the client side, have been attracting attention. The proposed thin client execution methods include network boot, server-based, blade PC, and virtual desktop (VDI) methods.

[0076] [Method for Driving Image Processing System] Next, an example of a method for driving an image processing system that can be realized by the electronic device 10 or the electronic device 10 and the server 80 will be described. Fig. 3 is a flowchart showing an example of a method for driving an image processing system. The flowchart shown in Fig. 3 has steps S0 to S6.

[0077] The process starts in step S0, where the electronic device 10 is ready for use.

[0078] In step S1, an instruction operation from a user is detected by the input device 22. For example, if the electronic device 10 has a touch panel, a touch operation (tap, swipe, etc.) by the user corresponds to the instruction operation. Also, if a mouse is used as the input means, an operation of the mouse (move, click, double-click, etc.) by the user corresponds to the instruction operation.

[0079] In step S2, the calculation unit 12 acquires position information from the input device 22 and the drive unit 24. In the case of a touch panel, the position information corresponds to the coordinates of the touch position. In the case of a mouse or the like, the position information corresponds to the coordinates of the cursor position.

[0080] In step S3, the calculation unit 12 executes a process (also called a division process) to determine a plurality of areas (regions) based on the position information. In the division process, the entire display area is divided into a plurality of regions based on the position information, and the result is output as area information. In the division process, division may be performed based on both the position information and image information. The area information output by the calculation unit 12 is used in subsequent image processing executed by the image processing unit 13.

[0081] Here, the processing of step S3 may be executed by the calculation unit 81 in the server 80. In that case, a step of transmitting the location information and image information to the server 80 is added between steps S2 and S3.

[0082] In step S4, the image processing unit 13 performs image processing according to the area of ​​the original image (first image) based on the area information generated by the above-mentioned segmentation process, and generates a processed image (second image). Note that there may be areas that are not subjected to image processing and that remain the original image. For example, if the image is segmented into two areas, image processing may be performed on only one area, or different image processing may be performed on both areas. If the image is segmented into three or more areas, different image processing may be performed on each of two areas, or different image processing may be performed on each of three areas.

[0083] Image processing can be, for example, a process of reducing resolution (also called down-conversion or down-scaling). For example, a method can be used in which the pixel values ​​of n x n pixels (n is an integer equal to or greater than 2) are set to the same value. The pixel values ​​can be determined by the mean, median, weighted mean, Gaussian distribution, or the like. Note that the down-conversion method is not limited to this, and various other methods can be used.

[0084] Image processing may also include processing to increase resolution (also called up-conversion or up-scaling). For example, it may be possible to display the part of the image that the user is gazing at at a higher resolution than the original image.

[0085] As image processing, a process of lowering the gradation (darkening the brightness) or a process of raising the gradation (increasing the brightness) can be used. Furthermore, as image processing, a process of raising or lowering the drive frequency (frame frequency) can also be used.

[0086] Lowering the drive frequency can reduce the power consumption of the electronic device 10. On the other hand, lowering the drive frequency also reduces the display quality. In particular, the display quality when displaying moving images is reduced. For example, by lowering the drive frequency in an area where the user's visibility is low, it is possible to reduce power consumption while suppressing a substantial decrease in display quality. According to one embodiment of the present invention, it is possible to maintain display quality and reduce power consumption at the same time.

[0087] For example, in an area where a display is performed at a high drive frequency (first drive frequency), the first drive frequency may be set to 30 Hz or more and 500 Hz or less, preferably 60 Hz or more and 400 Hz or less. On the other hand, in an area where a display is performed at a low drive frequency (second drive frequency), the second drive frequency is preferably 1 / 2 or less of the first drive frequency, and more preferably 1 / 5 or less of the first drive frequency. By reducing the drive frequency and significantly reducing the number of times the image is rewritten, power consumption can be further reduced. Furthermore, if necessary, image data rewriting may be stopped. By stopping image data rewriting, power consumption can be further reduced.

[0088] When such a driving method is performed, it is preferable to use a transistor with extremely low off-state current as a transistor constituting a pixel circuit of the display device 21. For example, it is preferable to use a transistor in which an oxide semiconductor is used as a semiconductor in which a channel is formed (OS transistor) as a transistor constituting a pixel circuit. Because the off-state current of an OS transistor is extremely low, image data supplied to the pixel circuit can be held for a long period of time.

[0089] The process of step S4 may be executed by the image processing unit 82 in the server 80. In this case, a step of transmitting the area information and the first image to the server 80 is added between steps S3 and S4.

[0090] Note that both the processes of steps S3 and S4 may be executed by the server 80.

[0091] In step S5, the second image is displayed on the display unit 11.

[0092] In step S6, the process ends.

[0093] Image Display Example 1 Next, an example of an image displayed using the image processing system of one embodiment of the present invention will be described, in which an electronic device having a touch panel is used.

[0094] [Display Example 1-1] Fig. 4A shows a background image 41 and an image 42 including text information displayed on the display unit 11. Fig. 4A also shows a state in which a user 40 swipes the image 42 with their finger, thereby scrolling the text information upward.

[0095] FIG. 4B shows an example of divided areas for the image displayed in FIG. 4A. Area 52 corresponds to the area where image 42 is displayed. Area 51 corresponds to the area where image 41 is displayed. Here, to distinguish between area 51 and area 52, different hatching patterns are used for each area. Area 52 displays a moving image in which text information moves upward, so reducing either or both of the resolution and frame frequency does not create a sense of incongruity. Therefore, area 52 is an area where image processing is performed to reduce either or both of the resolution and frame frequency. On the other hand, area 51 is an area where such image processing is not performed.

[0096] Furthermore, since the higher the frame frequency, the smoother the moving image can be displayed, image processing may be performed to increase the frame frequency in the case of fast-moving moving images, etc. For example, if the image is normally displayed at 60 Hz, the area where the moving image is displayed may be displayed at 90 Hz or 120 Hz.

[0097] 4B shows an example in which the areas are set in pixel units so that the shape of the divided areas roughly matches the shape of the displayed image, but the division positions of the areas may be determined in advance, which makes it easier to perform the calculation process for dividing the areas.

[0098] 5A shows an example in which the display unit 11 is divided into a plurality of areas 25 in advance. Here, the display unit 11 is divided into 4×8 (32) areas 25. Note that although the boundaries between the areas are shown by dashed lines in FIG. 5A, the boundaries are not actually displayed.

[0099] 5B shows an example of the divided areas. Area 52 is a 4×4 area including the area where image 42 is displayed. Area 51 is the other 16 areas.

[0100] Although an example in which the display unit 11 is divided into 4×8 sections is shown here, the greater the number of divisions, the more natural the image that can be displayed. On the other hand, the fewer the number of divisions, the less the load on the calculation process can be reduced.

[0101] [Display Example 1-2] The following shows an example of performing image processing based on the designated position.

[0102] Fig. 6A shows a state in which the finger of the user 40 is touching (tapping) the display unit 11. Fig. 6B shows an example of the divided areas at this time.

[0103] As shown in FIG. 6B , the display unit 11 is divided into a concentric region 51 centered on the contact position 50 of the user's 40 finger, a region 53 having a larger diameter than the region 51, and a region 52 located outside the region 53.

[0104] In many cases, when a user 40 taps the display unit 11, the user 40 focuses on the vicinity of the contact position 50. Therefore, the region 51 including the contact position 50 is displayed at the highest resolution and frame frequency, and the region 52 farthest from the contact position 50 is displayed at the lowest resolution or frame frequency. Furthermore, the region 53 located between the regions 51 and 52 can be displayed at a resolution and frame frequency equal to or lower than the region 51 but equal to or higher than the region 52. While an example of dividing the display unit into three types of regions is shown here, it may also be divided into four or more types of regions. It is preferable to determine the size of each region in advance, taking into account the characteristics of the human visual field. The size of each region may be changed as needed to match the distance between the user 40's eyes and the display unit 11.

[0105] Generally, human visual fields are broadly classified into the following five categories, although there are individual differences. The discriminative visual field is the area where visual functions such as visual acuity and color discrimination are at their best, and refers to the area including the point of gaze within approximately 5° of the center of the visual field. The effective visual field is the area where specific information can be instantly identified using eye movement alone, and refers to the area adjacent to the discriminative visual field, within approximately 30° horizontally and 20° vertically of the center of the visual field (point of gaze). The stable visual field is the area where specific information can be identified effortlessly with head movement, and refers to the area adjacent to the effective visual field, within approximately 90° horizontally and 70° vertically of the center of the visual field. The induced visual field is the area where the presence of a specific object can be detected but the ability to identify it is low, and refers to the area adjacent to the stable visual field, within approximately 100° horizontally and 85° vertically of the center of the visual field. The auxiliary visual field is an area in which the ability to distinguish specific objects is significantly reduced, but the presence of stimuli can be detected. It is an area within approximately 100° to 200° horizontally and approximately 85° to 130° vertically from the center of the visual field, adjacent to the induced visual field.

[0106] In this way, the load during video signal generation (rendering) is reduced by reducing the resolution of the image displayed in the area other than the area including the point of gaze. This type of processing is also called "foveated rendering." By combining foveated rendering with a reduction in the drive frequency of areas other than the area including the point of gaze, it is possible to further reduce power consumption while suppressing degradation in display quality.

[0107] 6C and 6D show an example in which the display unit 11 is divided in advance.

[0108] Here, if the display unit 11 has an optical sensor, it can acquire shape and position information of an obstacle (such as part of a hand) that exists between the screen and the eyes of the user 40. The part of the display unit 11 that is hidden by the obstacle, i.e., the area where the obstacle is projected onto the display unit 11, cannot be seen by the user and can therefore be turned off.

[0109] 7A and 7B , similar to FIG. 6A , show the display unit 11 being tapped with the finger of the user 40. As shown in FIG. 7B , an area 55 hidden by the finger and part of the hand of the user 40 is an area that is not displayed (equivalent to being displayed in black). In this way, by driving the device so that the area that is not visible to the user 40 is turned off, power consumption can be reduced more effectively.

[0110] 7C and 7D show examples in which the display unit 11 is divided in advance. In this case, a part of the area to be turned off may be visible to the user 40. Therefore, it is preferable that the user 40 be able to freely set whether or not to use the function of turning off the invisible area of ​​the display unit 11.

[0111] [Image Display Example 2] In the following, an example will be described in which an input means such as a mouse is used instead of a touch panel.

[0112] 8A includes a main body 61 and, as input means, a keyboard 62 and a mouse 63. Note that one or more input means are sufficient. For example, if the keyboard 62 includes a touchpad, the mouse 63 is not required.

[0113] The main body 61 has a display unit 70. The display unit 70 may have a function as a touch panel. Although not shown here, the main body 61 has at least a calculation unit 12, an image processing unit 13, and a communication unit 14 at positions overlapping the display unit 70. The main body 61 may also have a sensor unit 15, an imaging unit 16, an audio control unit 17, etc.

[0114] Electronic device 10A has a so-called multitasking function that allows multiple application programs to be executed simultaneously. Here, an example is shown in which a cursor 71, a window 72, a window 73, and a background 74 are displayed on display unit 70. Windows 72 and 73 correspond to different tasks, and different images are displayed in each.

[0115] 8A shows a state in which a scroll bar displayed in window 72 is operated to scroll the content displayed in window 72. In this case, the area showing window 72 is referred to as area 52, and the other area (the area showing window 73 and background 74) is referred to as area 51. An image with a lower resolution than area 51 is displayed in area 52. Furthermore, an image with a lower frequency or brightness than area 51 may be displayed in area 52.

[0116] 8B shows an example in which a plurality of regions are divided concentrically around the cursor 71. While the user is operating the mouse 63, the user often focuses on the cursor 71 or its vicinity. For this reason, the cursor 71 and its vicinity are displayed at a high resolution, and areas further away from the cursor 71 are displayed at a lower resolution, thereby reducing power consumption without causing a sense of incongruity to the user.

[0117] 8B, similarly to FIG. 6A, the area 51 including the cursor 71 is displayed at the highest resolution and frame frequency, while the area 52 farthest from the cursor 71 is displayed at the lowest resolution or frame frequency. The area 53 between the areas 51 and 52 is displayed at a resolution and frame frequency equal to or lower than the area 51 but equal to or higher than the area 52.

[0118] [Display Example 2-3] FIGS. 9A to 9C show examples of dividing areas based on the position of the cursor 71 and the image being displayed.

[0119] While the user is operating the mouse 63, the user often places the cursor 71 on the window on which he or she is working, and it can be assumed that the user is gazing at the window 72 overlaid with the cursor 71. For this reason, in Fig. 9A, the entire window 72 overlaid with the cursor 71 is designated as region 51, which is displayed at the highest resolution and frame frequency, and the other window 73 and background 74 are designated as region 52, which is displayed at the lowest resolution or frame frequency. Fig. 9B also shows an example in which the window 72 overlaid with the cursor 71 is designated as region 51.

[0120] As shown in FIG. 9C, when cursor 71 is not superimposed on any window but is superimposed on background 74, background 74 can be set as area 51, which is displayed at the highest resolution and frame frequency, and window 72 and window 73 can be set as area 52, which is displayed at the lowest resolution or lowest frame frequency.

[0121] In this way, by increasing the resolution of the work area (window) where the cursor is located and decreasing the resolution of other areas, power consumption can be effectively reduced.

[0122] Image processing may be performed to reduce the resolution to a level that the user can recognize. That is, the area that electronic device 10A recognizes as the work area can be displayed clearly, while other areas can be displayed blurred. This allows the user to recognize the area that electronic device 10A recognizes as the work area, thereby improving work efficiency.

[0123] Furthermore, once a window has been activated by mouse operation or the like, it may be displayed at a high resolution and frame frequency while the active state is maintained, while other areas may be displayed at a lower resolution or frame frequency. This allows power consumption to be reduced without causing a sense of incongruity to the user when the user switches from mouse operation to keyboard operation.

[0124] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0125] Embodiment 2 A configuration example of a display device that can be used in an image processing system of one embodiment of the present invention will be described below.

[0126] 10A and 10B are perspective views of the display device 310. Fig. 10B is a perspective view for explaining the configuration of each layer of the display device 310.

[0127] The display device 310 includes a substrate 320 and a substrate 312. The display device 310 includes a display portion 313 provided between the substrate 320 and the substrate 312. The display portion 313 includes a plurality of sub-display portions 319. A layer 360 is provided between the substrate 320 and the substrate 312. The substrate 312 is preferably a light-transmitting substrate or a layer made of a light-transmitting material.

[0128] The layer 360 is provided with a plurality of light-emitting elements 361. The layer 360 can be configured to be stacked on the substrate 320. As the light-emitting elements 361, for example, organic electroluminescence elements (also referred to as organic EL elements) can be used. However, the light-emitting elements 361 are not limited thereto, and for example, inorganic EL elements made of inorganic materials may also be used. Note that "organic EL elements" and "inorganic EL elements" may be collectively referred to as "EL elements." The light-emitting elements 361 may include inorganic compounds such as quantum dots. For example, quantum dots can be used in the light-emitting layer to function as a light-emitting material.

[0129] 10B , the pixel circuit group 335 including a plurality of pixel circuits, the drive circuit 330 (drive circuits 330a, 330b, 330c, and 330d), and the terminal portion 314 are provided on the same layer of the substrate 320. By providing the pixel circuit group 335 and the drive circuit 330 on the same layer, the wiring that electrically connects them can be shortened. This reduces wiring resistance and parasitic capacitance, and reduces power consumption.

[0130] For example, various transistors such as polysilicon transistors or OS transistors can be used as transistors for the display device 310. Both polysilicon transistors and OS transistors can also be used for the display device 310. In this case, both polysilicon transistors and OS transistors can be formed over the substrate 320.

[0131] The driver circuit 330 may be partially or entirely formed using one or both of a transistor in which polycrystalline silicon is used as a semiconductor in which a channel is formed (a poly-Si transistor) and an OS transistor. Alternatively, the driver circuit 330 may be formed using an IC chip manufactured using a single crystal silicon substrate.

[0132] Note that when the size of the display device 310 is small, such as 3 inches or less diagonally or 2 inches or less diagonally, a transistor in which single crystal silicon is used as a semiconductor in which a channel is formed (c-Si transistor) can also be used as the transistor used in the display device 310. By using a single crystal silicon substrate as the substrate 320, the pixel circuit group 335, the driver circuit 330, and the terminal portion 314 can be provided on the substrate 320. This can reduce the weight of the display device 310, reduce production costs, and further improve productivity.

[0133] 10A and 10B, the display unit 313 is configured with sub-display units 319 arranged in a matrix of m rows and n columns. Therefore, the pixel circuit group 335 is divided into sections 339 arranged in a matrix of m rows and n columns. Fig. 11 shows a planar layout of the substrate 320. Fig. 11 shows sections 339 when m is 4 and n is 8.

[0134] In the display device 310, the drive circuit 330 is divided into four regions: drive circuit 330a, drive circuit 330b, drive circuit 330c, and drive circuit 330d. The drive circuits 330a, 330b, 330c, and 330d are provided outside the pixel circuit group 335. Specifically, of the four sides of the periphery of the pixel circuit group 335, the drive circuit 330a is provided on a first side, the drive circuit 330c is provided on a third side facing the first side across the pixel circuit group 335, the drive circuit 330b is provided on a second side, and the drive circuit 330d is provided on a fourth side facing the second side across the pixel circuit group 335.

[0135] The drive circuit 330a and the drive circuit 330c each have 16 gate driver circuits 333. The drive circuit 330b and the drive circuit 330d each have 16 source driver circuits 331. One of the gate driver circuits 333 is electrically connected to a plurality of pixel circuits included in one of the sections 339. One of the source driver circuits 331 is electrically connected to a plurality of pixel circuits included in one of the sections 339.

[0136] In FIG. 11, the gate driver circuit 333 electrically connected to the section 339[i,j] (i is an integer of 1 or more and m or less, and j is an integer of 1 or more and n or less) is indicated as the gate driver circuit 333[i,j], and the source driver circuit 331 is indicated as the source driver circuit 331[i,j].

[0137] 11, the drive circuit 330a has 16 gate driver circuits 333 for four columns (j is from 1 to 4), and the drive circuit 330c has 16 gate driver circuits 333 for the remaining four columns (j is from 5 to 8). The drive circuit 330b has 16 source driver circuits 331 for two rows (i is from 1 to 2), and the drive circuit 330d has source driver circuits 331 for the remaining two rows (i is from 3 to 4).

[0138] The arrangement of the pixel circuit group 335 and the driver circuit 330 provided on the substrate 320 is not limited to the configuration shown in Fig. 11 . For example, the configuration shown in Fig. 12 may be used. In Fig. 12 , the driver circuit 330 is provided in two regions, a driver circuit 330a and a driver circuit 330b. For example, the driver circuit 330a is provided with 32 gate driver circuits 333 (gate driver circuits 333[1,1] to 333[4,8]), and the driver circuit 330b is provided with 32 source driver circuits 331 (source driver circuits 331[1,1] to 331[4,8]).

[0139] Such a display device 310 can be suitably used when the area is divided in advance, for example, as illustrated in Figures 5A and 5B of Embodiment 1. Here, the example shows the case where the display unit 313 is divided into 32 sub-display units 319, but the number of divisions is not limited to 32, and the display unit may be divided into 16, 64, 128, 256, 512, or 1024 divisions, etc. Increasing the number of divisions of the display unit 313 can further reduce the actual degradation in display quality felt by the user.

[0140] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0141] In this embodiment, a configuration example of a display device that can be used in an image processing system according to one embodiment of the present invention will be described. The display device described below can be applied to the display unit 11 or the display device 21 in Embodiment 1.

[0142] One embodiment of the present invention is a display device having light-emitting elements (also referred to as light-emitting devices). The display device has two or more light-emitting elements that emit different light colors. Each light-emitting element has a pair of electrodes and an EL layer therebetween. The light-emitting elements are preferably organic EL elements (organic electroluminescent elements). The two or more light-emitting elements that emit different light colors each have an EL layer containing a different light-emitting material. For example, a full-color display device can be realized by having three types of light-emitting elements that emit red (R), green (G), or blue (B) light, respectively.

[0143] When fabricating a display device having multiple light-emitting elements that emit different colors of light, it is necessary to form at least one layer containing a light-emitting material (light-emitting layer) in an island shape. When fabricating a partial or entire EL layer, a method of forming island-shaped organic films by vapor deposition using a shadow mask such as a metal mask is known. However, this method can cause deviations in the shape and position of the island-shaped organic films from the design due to various factors such as the accuracy of the metal mask, misalignment between the metal mask and the substrate, deflection of the metal mask, and spreading of the contours of the deposited film due to vapor scattering, making it difficult to achieve high-definition and high-aperture display devices. Furthermore, during vapor deposition, the contours of the layer can become blurred, resulting in thinning of the edges. In other words, the thickness of the island-shaped light-emitting layer can vary depending on the location. Furthermore, when fabricating large, high-resolution, or high-definition display devices, there is a concern that low dimensional accuracy of the metal mask and deformation due to heat, etc., can reduce manufacturing yield. Therefore, measures have been taken to artificially increase the resolution (also known as pixel density) by adopting special pixel arrangements such as a pentile array.

[0144] In this specification, the term "island-like" refers to a state in which two or more layers formed using the same material in the same process are physically separated. For example, an island-like light-emitting layer refers to a state in which the light-emitting layer is physically separated from an adjacent light-emitting layer.

[0145] In one embodiment of the present invention, an EL layer is processed into a fine pattern by photolithography without using a shadow mask such as a fine metal mask (FMM). This makes it possible to realize a display device with high definition and a large aperture ratio, which have been difficult to achieve until now. Furthermore, since the EL layer can be individually fabricated, a display device with extremely vivid images, high contrast, and high display quality can be realized. Note that, for example, the EL layer may be processed into a fine pattern using both a metal mask and photolithography.

[0146] Furthermore, the EL layer can be partially or entirely separated physically. This can suppress leakage current between adjacent light-emitting elements through a layer shared between the light-emitting elements (also referred to as a common layer). This can prevent crosstalk caused by unintended light emission, thereby realizing a display device with extremely high contrast. In particular, a display device with high current efficiency at low luminance can be realized.

[0147] One embodiment of the present invention can also be a display device that combines a white-emitting light-emitting element and a color filter. In this case, light-emitting elements provided in pixels (subpixels) that emit light of different colors can have the same configuration, and all layers can be common layers. Furthermore, part or all of each EL layer is separated by photolithography. This suppresses leakage current through the common layer, thereby realizing a display device with high contrast. In particular, in an element having a tandem structure in which multiple light-emitting layers are stacked via a highly conductive intermediate layer, leakage current through the intermediate layer can be effectively prevented, thereby realizing a display device that combines high brightness, high definition, and high contrast.

[0148] Furthermore, it is preferable to provide an insulating layer that covers at least the side surfaces of the island-shaped light-emitting layers. The insulating layer may be configured to cover a portion of the top surface of the island-shaped EL layer. The insulating layer is preferably made of a material that has barrier properties against water and oxygen. For example, an inorganic insulating film that is difficult for water or oxygen to diffuse can be used. This suppresses deterioration of the EL layer and realizes a highly reliable display device.

[0149] Furthermore, there is a region (recess) between two adjacent light-emitting elements where the EL layer of either light-emitting element is not provided. When a common electrode, or a common electrode and a common layer, is formed to cover the recess, a phenomenon in which the common electrode is separated by a step at the edge of the EL layer (also called a step discontinuity) may occur, resulting in insulation of the common electrode on the EL layer. Therefore, it is preferable to use a configuration in which the local step located between two adjacent light-emitting elements is filled with a resin layer functioning as a planarization film (also called LFP: Local Filling Planarization). The resin layer functions as a planarization film. This suppresses step discontinuity of the common layer or common electrode, thereby achieving a highly reliable display device.

[0150] A more specific example of the structure of the display device of one embodiment of the present invention will be described below with reference to the drawings.

[0151] 13A shows a schematic top view of a display device 100 of one embodiment of the present invention. The display device 100 includes a plurality of light-emitting elements 110R that exhibit red light, a plurality of light-emitting elements 110G that exhibit green light, and a plurality of light-emitting elements 110B that exhibit blue light, over a substrate 101. In FIG. 13A , the symbols R, G, and B are assigned within the light-emitting regions of the light-emitting elements to easily distinguish the light-emitting elements from one another.

[0152] The light emitting elements 110R, 110G, and 110B are arranged in a matrix. Fig. 13A shows a so-called stripe arrangement in which light emitting elements of the same color are arranged in one direction. Note that the arrangement method of the light emitting elements is not limited to this, and arrangement methods such as an S-stripe arrangement, a delta arrangement, a Bayer arrangement, or a zigzag arrangement may also be used, or a pentile arrangement, a diamond arrangement, or the like may also be used.

[0153] As the light-emitting element 110R, the light-emitting element 110G, and the light-emitting element 110B, for example, an OLED (organic light-emitting diode) or a QLED (quantum-dot light-emitting diode) is preferably used. Examples of the light-emitting substance contained in the EL element include a substance that emits fluorescence (fluorescent material), a substance that emits phosphorescence (phosphorescent material), and a substance that exhibits thermally activated delayed fluorescence (thermally activated delayed fluorescence: TADF material). As the light-emitting substance contained in the EL element, not only organic compounds but also inorganic compounds (such as quantum dot materials) can be used.

[0154] 13A also shows a connection electrode 111C that is electrically connected to the common electrode 113. The connection electrode 111C is given a potential (e.g., an anode potential or a cathode potential) to be supplied to the common electrode 113. The connection electrode 111C is provided outside the display area where the light-emitting elements 110R and the like are arranged.

[0155] The connection electrode 111C can be provided along the periphery of the display area. For example, it can be provided along one side of the periphery of the display area, or it can be provided along two or more sides of the periphery of the display area. That is, if the top surface shape of the display area is rectangular, the top surface shape of the connection electrode 111C can be strip-shaped (rectangular), L-shaped, U-shaped (bracket-shaped), square, or the like. Note that in this specification, the top surface shape of a certain component refers to the contour shape of the component in a planar view. Furthermore, a planar view refers to a view from the normal direction of the surface on which the component is formed or the surface of a support (e.g., a substrate) on which the component is formed.

[0156] 13B and 13C are schematic cross-sectional views corresponding to dashed dotted lines A1-A2 and A3-A4 in Fig. 13A, respectively. Fig. 13B shows a schematic cross-sectional view of light-emitting element 110R, light-emitting element 110G, and light-emitting element 110B, and Fig. 13C shows a schematic cross-sectional view of connection portion 140 where connection electrode 111C and common electrode 113 are connected.

[0157] The light-emitting element 110R has a pixel electrode 111R, an organic layer 112R, a common layer 114, and a common electrode 113. The light-emitting element 110G has a pixel electrode 111G, an organic layer 112G, a common layer 114, and a common electrode 113. The light-emitting element 110B has a pixel electrode 111B, an organic layer 112B, a common layer 114, and a common electrode 113. The common layer 114 and the common electrode 113 are provided in common to the light-emitting element 110R, the light-emitting element 110G, and the light-emitting element 110B.

[0158] The organic layer 112R of the light-emitting element 110R contains a light-emitting organic compound that emits at least red light. The organic layer 112G of the light-emitting element 110G contains a light-emitting organic compound that emits at least green light. The organic layer 112B of the light-emitting element 110B contains a light-emitting organic compound that emits at least blue light. The organic layer 112R, the organic layer 112G, and the organic layer 112B can also be called EL layers, and each contains at least a layer (light-emitting layer) that contains a light-emitting organic compound.

[0159] Hereinafter, when describing matters common to light emitting element 110R, light emitting element 110G, and light emitting element 110B, they may be referred to as light emitting element 110. Similarly, when describing matters common to components distinguished by alphabets, such as organic layer 112R, organic layer 112G, and organic layer 112B, they may be described using symbols without the alphabets.

[0160] The organic layer 112 and the common layer 114 may each independently include one or more of an electron injection layer, an electron transport layer, a hole injection layer, and a hole transport layer. For example, the organic layer 112 may have a stacked structure of a hole injection layer, a hole transport layer, a light-emitting layer, and an electron transport layer from the pixel electrode 111 side, and the common layer 114 may have an electron injection layer.

[0161] The pixel electrode 111R, pixel electrode 111G, and pixel electrode 111B are provided for each light-emitting element. The common electrode 113 and common layer 114 are provided as a continuous layer common to each light-emitting element. A conductive film transmissive to visible light is used for either the pixel electrode or the common electrode 113, and a conductive film reflective to visible light is used for the other. By making each pixel electrode transmissive and the common electrode 113 reflective, a bottom-emission display device can be obtained. Conversely, by making each pixel electrode reflective and the common electrode 113 transmissive, a top-emission display device can be obtained. Note that by making both the pixel electrodes and the common electrode 113 transmissive, a dual-emission display device can be obtained.

[0162] A protective layer 121 is provided on the common electrode 113 to cover the light emitting elements 110R, 110G, and 110B. The protective layer 121 has a function of preventing impurities such as water from diffusing from above into each light emitting element.

[0163] The edge of the pixel electrode 111 preferably has a tapered shape. When the edge of the pixel electrode has a tapered shape, the organic layer 112 provided along the side surface of the pixel electrode also has a tapered shape. By tapering the side surface of the pixel electrode, the coverage of the EL layer provided along the side surface of the pixel electrode can be improved. Furthermore, by tapering the side surface of the pixel electrode, foreign matter (for example, dust or particles) during the manufacturing process can be easily removed by a process such as cleaning, which is preferable.

[0164] In this specification and the like, the term "tapered shape" refers to a shape in which at least a part of a side surface of a structure is inclined with respect to a substrate surface. For example, it is preferable that the structure has a region in which the angle between the inclined side surface and the substrate surface (also referred to as the taper angle) is less than 90°.

[0165] The organic layer 112 is processed into an island shape by photolithography. As a result, the angle between the top surface and the side surface of the organic layer 112 at its edge is close to 90 degrees. On the other hand, an organic film formed using a fine metal mask (FMM) or the like tends to become gradually thinner as it approaches the edge. For example, the top surface is formed in a sloped shape over a range of 1 μm to 10 μm up to the edge, making it difficult to distinguish between the top surface and the side surface.

[0166] Between two adjacent light emitting elements, an insulating layer 125, a resin layer 126, and a layer 128 are provided.

[0167] Between two adjacent light-emitting elements, the side surfaces of the organic layers 112 face each other with the resin layer 126 interposed therebetween. The resin layer 126 is located between the two adjacent light-emitting elements and is provided so as to fill the ends of each organic layer 112 and the region between the two organic layers 112. The upper surface of the resin layer 126 has a smooth convex shape, and a common layer 114 and a common electrode 113 are provided to cover the upper surface of the resin layer 126.

[0168] The resin layer 126 functions as a planarization film that fills in a step between two adjacent light-emitting elements. By providing the resin layer 126, it is possible to prevent a phenomenon (also called step disconnection) in which the common electrode 113 is divided by a step at the end of the organic layer 112, resulting in insulation of the common electrode on the organic layer 112. The resin layer 126 can also be called an LFP (Local Filling Planarization) layer.

[0169] An insulating layer containing an organic material can be suitably used as the resin layer 126. For example, acrylic resin, polyimide resin, epoxy resin, imide resin, polyamide resin, polyimideamide resin, silicone resin, siloxane resin, benzocyclobutene resin, phenolic resin, precursors of these resins, etc. can be used as the resin layer 126. Alternatively, organic materials such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, or alcohol-soluble polyamide resin can be used as the resin layer 126.

[0170] Furthermore, a photosensitive resin can be used as the resin layer 126. A photoresist can be used as the photosensitive resin. The photosensitive resin can be a positive-type material or a negative-type material.

[0171] The resin layer 126 may contain a material that absorbs visible light. For example, the resin layer 126 itself may be made of a material that absorbs visible light, or the resin layer 126 may contain a pigment that absorbs visible light. For example, the resin layer 126 may be a resin that can be used as a color filter that transmits red, blue, or green light and absorbs other light, or a resin that contains carbon black as a pigment and functions as a black matrix.

[0172] The insulating layer 125 is provided in contact with the side surface of the organic layer 112. The insulating layer 125 is also provided to cover the upper end portion of the organic layer 112. A portion of the insulating layer 125 is provided in contact with the upper surface of the substrate 101.

[0173] The insulating layer 125 is located between the resin layer 126 and the organic layer 112, and functions as a protective film for preventing the resin layer 126 from contacting the organic layer 112. If the organic layer 112 and the resin layer 126 come into contact with each other, the organic layer 112 may be dissolved by an organic solvent or the like used when forming the resin layer 126. Therefore, as shown in this embodiment, by providing the insulating layer 125 between the organic layer 112 and the resin layer 126, it is possible to protect the side surfaces of the organic layer.

[0174] The insulating layer 125 can be an insulating layer containing an inorganic material. For example, an inorganic insulating film such as an oxide insulating film, a nitride insulating film, an oxynitride insulating film, or a nitride oxide insulating film can be used for the insulating layer 125. The insulating layer 125 may have a single-layer structure or a stacked-layer structure. Examples of oxide insulating films include a silicon oxide film, an aluminum oxide film, a magnesium oxide film, an indium gallium zinc oxide film, a gallium oxide film, a germanium oxide film, an yttrium oxide film, a zirconium oxide film, a lanthanum oxide film, a neodymium oxide film, a hafnium oxide film, and a tantalum oxide film. Examples of nitride insulating films include a silicon nitride film and an aluminum nitride film. Examples of oxynitride insulating films include a silicon oxynitride film and an aluminum oxynitride film. Examples of nitride oxide insulating films include a silicon nitride oxide film and an aluminum nitride oxide film. In particular, by using an inorganic insulating film such as a metal oxide film, an aluminum oxide film, or a silicon oxide film formed by an ALD method as the insulating layer 125, an insulating layer 125 with few pinholes and excellent protection of the EL layer can be formed.

[0175] In this specification and elsewhere, an oxynitride refers to a material whose composition contains more oxygen than nitrogen, and a nitride oxide refers to a material whose composition contains more nitrogen than oxygen. For example, silicon oxynitride refers to a material whose composition contains more oxygen than nitrogen, and silicon nitride oxide refers to a material whose composition contains more nitrogen than oxygen.

[0176] The insulating layer 125 can be formed by a sputtering method, a CVD method, a PLD method, an ALD method, or the like. The insulating layer 125 is preferably formed by an ALD method because it has good coverage.

[0177] Furthermore, a reflective film (e.g., a metal film containing one or more selected from silver, palladium, copper, titanium, aluminum, etc.) may be provided between the insulating layer 125 and the resin layer 126, so that the light emitted from the light-emitting layer is reflected by the reflective film, thereby improving the light extraction efficiency.

[0178] The layer 128 is a remaining portion of a protective layer (also referred to as a mask layer or a sacrificial layer) for protecting the organic layer 112 during etching of the organic layer 112. The layer 128 can be made of a material that can be used for the insulating layer 125. In particular, it is preferable to use the same material for the layer 128 and the insulating layer 125 because a common processing device or the like can be used for both.

[0179] In particular, inorganic insulating films such as metal oxide films such as aluminum oxide films and hafnium oxide films, or silicon oxide films formed by the ALD method have few pinholes and therefore have an excellent function of protecting the EL layer, and can be suitably used for the insulating layer 125 and the layer 128.

[0180] A protective layer 121 is provided to cover the common electrode 113 .

[0181] The protective layer 121 may have, for example, a single-layer structure or a stacked structure including at least an inorganic insulating film. Examples of the inorganic insulating film include oxide films or nitride films such as a silicon oxide film, a silicon oxynitride film, a silicon nitride oxide film, a silicon nitride film, an aluminum oxide film, an aluminum oxynitride film, and a hafnium oxide film. Alternatively, the protective layer 121 may be made of a semiconductor material or a conductive material such as indium gallium oxide, indium zinc oxide, indium tin oxide, or indium gallium zinc oxide.

[0182] The protective layer 121 may also be a laminated film of an inorganic insulating film and an organic insulating film. For example, a configuration in which an organic insulating film is sandwiched between a pair of inorganic insulating films is preferable. Furthermore, it is preferable that the organic insulating film functions as a planarizing film. This allows the upper surface of the organic insulating film to be flat, improving the coverage of the inorganic insulating film thereon and enhancing the barrier properties. Furthermore, since the upper surface of the protective layer 121 is flat, when a structure (e.g., a color filter, a touch sensor electrode, a lens array, etc.) is provided above the protective layer 121, the influence of uneven shapes caused by the structure below can be reduced, which is preferable.

[0183] 13C shows a connection portion 140 where the connection electrode 111C and the common electrode 113 are electrically connected. In the connection portion 140, an opening is provided in the insulating layer 125 and the resin layer 126 above the connection electrode 111C. The connection electrode 111C and the common electrode 113 are electrically connected in the opening.

[0184] 13C shows a connection portion 140 where the connection electrode 111C and the common electrode 113 are electrically connected, but the common electrode 113 may be provided on the connection electrode 111C via the common layer 114. In particular, when a carrier injection layer is used for the common layer 114, the electrical resistivity of the material used for the common layer 114 is sufficiently low and the common layer 114 can be formed thin, so there are many cases where no problem occurs even if the common layer 114 is located at the connection portion 140. This allows the common electrode 113 and the common layer 114 to be formed using the same masking mask, thereby reducing manufacturing costs.

[0185] The above is a description of an example of the configuration of the display device.

[0186] [Pixel Layout] The following mainly describes pixel layouts that are different from that shown in Fig. 13A. There are no particular limitations on the arrangement of light-emitting elements (sub-pixels), and various methods can be applied.

[0187] Examples of the top surface shape of the sub-pixel include a triangle, a quadrangle (including a rectangle and a square), a polygon such as a pentagon, a polygon with rounded corners, an ellipse, a circle, etc. Here, the top surface shape of the sub-pixel corresponds to the top surface shape of the light-emitting region of the light-emitting element.

[0188] An S-stripe arrangement is applied to the pixel 150 shown in Fig. 14A. The pixel 150 shown in Fig. 14A is composed of three sub-pixels, namely, light-emitting elements 110a, 110b, and 110c. For example, the light-emitting element 110a may be a blue light-emitting element, the light-emitting element 110b may be a red light-emitting element, and the light-emitting element 110c may be a green light-emitting element.

[0189] The pixel 150 shown in FIG. 14B includes a light-emitting element 110a having a generally trapezoidal top surface shape with rounded corners, a light-emitting element 110b having a generally triangular top surface shape with rounded corners, and a light-emitting element 110c having a generally rectangular or hexagonal top surface shape with rounded corners. Furthermore, the light-emitting element 110a has a larger light-emitting area than the light-emitting element 110b. In this manner, the shape and size of each light-emitting element can be determined independently. For example, the more reliable the light-emitting element, the smaller the size can be. For example, the light-emitting element 110a may be a green light-emitting element, the light-emitting element 110b may be a red light-emitting element, and the light-emitting element 110c may be a blue light-emitting element.

[0190] The pixels 124a and 124b shown in Fig. 14C are arranged in a Pentile arrangement. Fig. 14C shows an example in which a pixel 124a having light-emitting elements 110a and 110b and a pixel 124b having light-emitting elements 110b and 110c are arranged alternately. For example, the light-emitting element 110a may be a red light-emitting element, the light-emitting element 110b may be a green light-emitting element, and the light-emitting element 110c may be a blue light-emitting element.

[0191] 14D and 14E are arranged in a delta configuration. The pixel 124a has two light-emitting elements (light-emitting elements 110a and 110b) in the top row (first row) and one light-emitting element (light-emitting element 110c) in the bottom row (second row). The pixel 124b has one light-emitting element (light-emitting element 110c) in the top row (first row) and two light-emitting elements (light-emitting elements 110a and 110b) in the bottom row (second row). For example, the light-emitting element 110a may be a red light-emitting element, the light-emitting element 110b may be a green light-emitting element, and the light-emitting element 110c may be a blue light-emitting element.

[0192] FIG. 14D shows an example in which each light-emitting element has a substantially rectangular top surface shape with rounded corners, and FIG. 14E shows an example in which each light-emitting element has a circular top surface shape.

[0193] 14F shows an example in which light-emitting elements of each color are arranged in a zigzag pattern. Specifically, when viewed from above, the positions of the upper edges of two light-emitting elements arranged in a column direction (e.g., light-emitting elements 110a and 110b, or light-emitting elements 110b and 110c) are misaligned. For example, light-emitting element 110a may be a red light-emitting element, light-emitting element 110b may be a green light-emitting element, and light-emitting element 110c may be a blue light-emitting element.

[0194] In photolithography, the finer the pattern to be processed, the more significant the effect of light diffraction becomes. This reduces the fidelity of the photomask pattern when it is transferred by exposure, making it difficult to process the resist mask into the desired shape. Therefore, even if the photomask pattern is rectangular, it is likely to have rounded corners. As a result, the top surface shape of the light-emitting element may be polygonal with rounded corners, elliptical, circular, or the like.

[0195] Furthermore, in a manufacturing method of a display panel according to one embodiment of the present invention, the EL layer is processed into an island shape using a resist mask. The resist film formed on the EL layer needs to be cured at a temperature lower than the heat resistance temperature of the EL layer. Therefore, depending on the heat resistance temperature of the material for the EL layer and the curing temperature of the resist material, the resist film may not be cured sufficiently. A resist film that is not cured sufficiently may have a shape that is different from the desired shape during processing. As a result, the top surface shape of the EL layer may become a polygon with rounded corners, an ellipse, a circle, or the like. For example, when a resist mask with a square top surface shape is formed, a resist mask with a circular top surface shape may be formed, resulting in a circular top surface shape of the EL layer.

[0196] In order to form the top surface of the EL layer into a desired shape, a technique for correcting a mask pattern in advance (OPC (Optical Proximity Correction) technique) may be used so that the design pattern and the transfer pattern coincide with each other. Specifically, the OPC technique adds a correction pattern to the corners of figures on the mask pattern.

[0197] This concludes the description of the pixel layout.

[0198] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0199] Embodiment 4 In this embodiment, a configuration example of a display device that can be applied to an image processing system of one embodiment of the present invention will be described.

[0200] The display device of this embodiment can be used in electronic devices with relatively large screens, such as television devices, desktop or notebook personal computers, computer monitors, digital signage, large game machines such as pachinko machines, as well as display units of digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, smartphones, wristwatch-type terminals, tablet terminals, personal digital assistants, audio playback devices, goggle-type displays, etc.

[0201] [Display Device 400] FIG. 15 shows a perspective view of display device 400, and FIG. 16A shows a cross-sectional view of display device 400.

[0202] The display device 400 has a configuration in which a substrate 454 and a substrate 451 are bonded together. In Fig. 15, the substrate 454 is clearly indicated by a dashed line.

[0203] The display device 400 includes a display portion 462, a circuit 464, wiring 465, and the like. Fig. 15 shows an example in which an IC 473 and an FPC 472 are mounted on the display device 400. Therefore, the structure shown in Fig. 15 can also be considered as a display module including the display device 400, an IC (integrated circuit), and an FPC.

[0204] The circuit 464 can be, for example, a scanning line driver circuit.

[0205] The wiring 465 has a function of supplying signals and power to the display portion 462 and the circuit 464. The signals and power are input to the wiring 465 from the outside via the FPC 472 or input to the wiring 465 from the IC 473.

[0206] 15 shows an example in which an IC 473 is provided on a substrate 451 by a chip-on-glass (COG) method, a chip-on-film (COF) method, or the like. The IC 473 can be, for example, an IC having a scanning line driver circuit or a signal line driver circuit. The display device 400 and the display module may not include an IC. Alternatively, the IC may be mounted on an FPC by a COF method or the like.

[0207] 16A shows an example of a cross section of the display device 400, where a part of a region including the FPC 472, a part of the circuit 464, a part of the display portion 462, and a part of a region including a connection portion are cut away. In FIG. 16A, an example of a cross section of the display portion 462, particularly, a region including the light-emitting element 430b that emits green light and the light-emitting element 430c that emits blue light, is cut away.

[0208] The display device 400 shown in FIG. 16A includes the transistor 202, the transistor 210, the light-emitting element 430b, the light-emitting element 430c, and the like between a substrate 453 and a substrate 454.

[0209] Here, when a pixel of a display device has three types of sub-pixels having light-emitting elements of different luminescent colors, the three sub-pixels include sub-pixels of three colors of red (R), green (G), and blue (B), or sub-pixels of three colors of yellow (Y), cyan (C), and magenta (M), etc. When a pixel of a display device has four sub-pixels, the four sub-pixels include sub-pixels of four colors of R, G, B, and white (W), or sub-pixels of four colors of R, G, B, and Y, etc.

[0210] The substrate 454 and the protective layer 416 are bonded to each other via an adhesive layer 442. The adhesive layer 442 is provided to overlap the light-emitting element 430b and the light-emitting element 430c, and a solid sealing structure is applied to the display device 400.

[0211] The light-emitting elements 430b and 430c each include a conductive layer 411a, a conductive layer 411b, and a conductive layer 411c as pixel electrodes. The conductive layer 411b is reflective to visible light and functions as a reflective electrode. The conductive layer 411c is transparent to visible light and functions as an optical adjustment layer.

[0212] The conductive layer 411a is connected to a conductive layer 222b of the transistor 210 through an opening provided in the insulating layer 214. The transistor 210 has a function of controlling the driving of a light-emitting element.

[0213] An EL layer 412G or an EL layer 412B is provided to cover the pixel electrode. An insulating layer 421 is provided in contact with the side surfaces of the EL layer 412G and the EL layer 412B, and a resin layer 422 is provided to fill the recesses in the insulating layer 421. A layer 424 is provided between the EL layer 412G and the insulating layer 421, and between the EL layer 412B and the insulating layer 421. A common layer 414, a common electrode 413, and a protective layer 416 are provided to cover the EL layer 412G and the EL layer 412B.

[0214] Light emitted from the light-emitting element is emitted toward the substrate 454. The substrate 454 is preferably made of a material that is highly transparent to visible light.

[0215] The transistor 202 and the transistor 210 are both formed over a substrate 451. These transistors can be manufactured using the same material and through the same process.

[0216] The substrate 453 and the insulating layer 212 are bonded together by an adhesive layer 455 .

[0217] The display device 400 is manufactured by first bonding a substrate 454 provided with the insulating layer 212, the transistors, the light-emitting elements, and the like to the substrate 454 with an adhesive layer 442. The substrate 453 is then attached to the exposed surface of the substrate 454, and the components formed on the substrate 454 are transferred to the substrate 453. The substrate 453 and the substrate 454 are preferably flexible. This can increase the flexibility of the display device 400.

[0218] The insulating layer 212 can be formed using the inorganic insulating film that can be used for the insulating layer 211 and the insulating layer 215 .

[0219] A connection portion 204 is provided in a region of the substrate 453 where the substrate 454 does not overlap. In the connection portion 204, a wiring 465 is electrically connected to an FPC 472 via a conductive layer 466 and a connection layer 242. The conductive layer 466 can be obtained by processing the same conductive film as the pixel electrode. This allows the connection portion 204 and the FPC 472 to be electrically connected via the connection layer 242.

[0220] The transistor 202 and the transistor 210 each include a conductive layer 221 functioning as a gate, an insulating layer 211 functioning as a gate insulating layer, a semiconductor layer 231 including a channel formation region 231i and a pair of low-resistance regions 231n, a conductive layer 222a connected to one of the pair of low-resistance regions 231n, a conductive layer 222b connected to the other of the pair of low-resistance regions 231n, an insulating layer 225 functioning as a gate insulating layer, a conductive layer 223 functioning as a gate, and an insulating layer 215 covering the conductive layer 223. The insulating layer 211 is located between the conductive layer 221 and the channel formation region 231i. The insulating layer 225 is located between the conductive layer 223 and the channel formation region 231i.

[0221] The conductive layer 222a and the conductive layer 222b are each connected to the low-resistance region 231n through an opening provided in the insulating layer 215. One of the conductive layer 222a and the conductive layer 222b functions as a source, and the other functions as a drain.

[0222] 16A shows an example in which the top surface and side surfaces of the semiconductor layer are covered with an insulating layer 225. The conductive layer 222a and the conductive layer 222b are connected to the low-resistance region 231n through openings provided in the insulating layer 225 and the insulating layer 215, respectively.

[0223] 16B , the insulating layer 225 overlaps with the channel formation region 231i of the semiconductor layer 231 but does not overlap with the low-resistance region 231n. For example, the insulating layer 225 is processed using the conductive layer 223 as a mask, thereby manufacturing the structure shown in FIG. 16B . In FIG. 16B , the insulating layer 215 is provided to cover the insulating layer 225 and the conductive layer 223, and the conductive layer 222a and the conductive layer 222b are connected to the low-resistance region 231n through openings in the insulating layer 215. Furthermore, an insulating layer 218 may be provided to cover the transistor.

[0224] The structure of the transistor included in the display device of this embodiment is not particularly limited. For example, a planar transistor, a staggered transistor, an inverted staggered transistor, or the like can be used. Furthermore, either a top-gate transistor or a bottom-gate transistor structure may be used. Alternatively, gates may be provided above and below a semiconductor layer in which a channel is formed.

[0225] The transistor 202 and the transistor 210 have a structure in which a semiconductor layer in which a channel is formed is sandwiched between two gates. The two gates may be connected and the same signal may be supplied to drive the transistor. Alternatively, the threshold voltage of the transistor may be controlled by applying a potential for controlling the threshold voltage to one of the two gates and a potential for driving to the other.

[0226] The crystallinity of a semiconductor material used for a semiconductor layer of a transistor is not particularly limited, and any of an amorphous semiconductor, a single-crystal semiconductor, and a semiconductor having crystallinity other than single crystal (a microcrystalline semiconductor, a polycrystalline semiconductor, or a semiconductor having a crystalline region in part) may be used. The use of a single-crystal semiconductor or a crystalline semiconductor is preferable because it can suppress deterioration of transistor characteristics.

[0227] The semiconductor layer of the transistor preferably includes a metal oxide (also referred to as an oxide semiconductor). That is, the display device of this embodiment preferably includes a transistor using a metal oxide for a channel formation region (hereinafter referred to as an OS transistor).

[0228] The band gap of the metal oxide used for the semiconductor layer of the transistor is preferably 2 eV or more, more preferably 2.5 eV or more. Use of a metal oxide with a wide band gap can reduce the off-state current of the OS transistor.

[0229] The metal oxide preferably contains at least indium or zinc, and more preferably contains indium and zinc. For example, the metal oxide preferably contains indium, M (wherein M is one or more selected from gallium, aluminum, yttrium, tin, silicon, boron, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, magnesium, and cobalt), and zinc.

[0230] Alternatively, the semiconductor layer of the transistor may contain silicon, such as amorphous silicon or crystalline silicon (such as low-temperature polysilicon or single-crystal silicon).

[0231] The transistors included in the circuit 464 may have the same structure as or different from the transistors included in the display portion 462. The transistors included in the circuit 464 may all have the same structure or may have two or more types of structures. Similarly, the transistors included in the display portion 462 may all have the same structure or may have two or more types of structures.

[0232] At least one insulating layer covering the transistor is preferably made of a material that is resistant to the diffusion of impurities such as water and hydrogen. This allows the insulating layer to function as a barrier layer. With this structure, it is possible to effectively prevent impurities from diffusing into the transistor from the outside, thereby improving the reliability of the display device.

[0233] It is preferable to use an inorganic insulating film for each of the insulating layers 211, 212, 215, 218, and 225. Examples of the inorganic insulating film that can be used include a silicon nitride film, a silicon oxynitride film, a silicon oxide film, a silicon nitride oxide film, an aluminum oxide film, and an aluminum nitride film. Alternatively, a hafnium oxide film, an yttrium oxide film, a zirconium oxide film, a gallium oxide film, a tantalum oxide film, a magnesium oxide film, a lanthanum oxide film, a cerium oxide film, and a neodymium oxide film may also be used. Two or more of the above-described inorganic insulating films may be stacked.

[0234] An organic insulating film is suitable for the insulating layer 214 that functions as a planarizing layer. Materials that can be used for the organic insulating film include acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimideamide resin, siloxane resin, benzocyclobutene resin, phenol resin, and precursors of these resins.

[0235] Various optical members can be arranged along the inner or outer surface of substrate 454. Examples of optical members include a light-shielding layer, a polarizing plate, a retardation plate, a light diffusion layer (such as a diffusion film), an anti-reflection layer, a microlens array, and a light-collecting film. In addition, an antistatic film that suppresses the adhesion of dust, a water-repellent film that makes it difficult for dirt to adhere, a hard coat film that suppresses scratches caused by use, an impact absorbing layer, etc. may be arranged on the outer surface of substrate 454.

[0236] By providing the protective layer 416 that covers the light-emitting element, impurities such as water can be prevented from entering the light-emitting element, and the reliability of the light-emitting element can be improved.

[0237] 16A shows a connection portion 228. The common electrode 413 and a wiring are electrically connected at the connection portion 228. In FIG. 16A, an example is shown in which the same layered structure as that of the pixel electrode is applied to the wiring.

[0238] The substrate 453 and the substrate 454 can each be made of glass, quartz, ceramics, sapphire, resin, metal, alloy, semiconductor, or the like. A material that transmits light is used for the substrate on the side from which light from the light-emitting element is extracted. When a flexible material is used for the substrate 453 and the substrate 454, the flexibility of the display device can be increased. Alternatively, a polarizing plate may be used for the substrate 453 or the substrate 454.

[0239] The substrates 453 and 454 can each be made of a polyester resin such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), a polyacrylonitrile resin, an acrylic resin, a polyimide resin, a polymethyl methacrylate resin, a polycarbonate (PC) resin, a polyethersulfone (PES) resin, a polyamide resin (nylon, aramid, etc.), a polysiloxane resin, a cycloolefin resin, a polystyrene resin, a polyamideimide resin, a polyurethane resin, a polyvinyl chloride resin, a polyvinylidene chloride resin, a polypropylene resin, a polytetrafluoroethylene (PTFE) resin, an ABS resin, or a cellulose nanofiber. One or both of the substrates 453 and 454 may be made of glass having a thickness sufficient to provide flexibility.

[0240] The adhesive layer can be made of various curable adhesives, such as photo-curable adhesives (e.g., ultraviolet curable), reactive curable adhesives, thermosetting adhesives, and anaerobic adhesives. Examples of such adhesives include epoxy resin, acrylic resin, silicone resin, phenolic resin, polyimide resin, imide resin, PVC (polyvinyl chloride) resin, PVB (polyvinyl butyral) resin, and EVA (ethylene vinyl acetate) resin. Materials with low moisture permeability, such as epoxy resin, are particularly preferred. Two-component resins may also be used. Adhesive sheets, etc., may also be used.

[0241] The connection layer 242 may be an anisotropic conductive film (ACF), an anisotropic conductive paste (ACP), or the like.

[0242] Materials that can be used for conductive layers such as the gate, source, and drain of a transistor, as well as various wirings and electrodes that constitute a display device include metals such as aluminum, titanium, chromium, nickel, copper, yttrium, zirconium, molybdenum, silver, tantalum, and tungsten, and alloys containing these metals as main components, etc. Films containing these materials can be used as a single layer or a stacked layer structure.

[0243] Examples of light-transmitting conductive materials include conductive oxides such as indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, and zinc oxide containing gallium, or graphene. Alternatively, metal materials such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, and titanium, or alloy materials containing such metal materials, can be used. Alternatively, nitrides of such metal materials (e.g., titanium nitride) can be used. When using metal materials or alloy materials (or their nitrides), it is preferable to thin them sufficiently to ensure light-transmitting properties. A stacked film of the above materials can also be used as the conductive layer. For example, a stacked film of an alloy of silver and magnesium and indium tin oxide is preferable because it can enhance conductivity. These materials can also be used for conductive layers such as various wirings and electrodes constituting a display device, and for conductive layers (conductive layers functioning as pixel electrodes or common electrodes) of light-emitting elements.

[0244] Examples of insulating materials that can be used for each insulating layer include resins such as acrylic resin and epoxy resin, and inorganic insulating materials such as silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, and aluminum oxide.

[0245] [Display Device 400A] A display device 400A shown in FIG. 17 is an example of a liquid crystal display device that uses liquid crystal elements as display elements.

[0246] The display device 400A includes the transistor 201, the transistor 205, the liquid crystal element 480, and the like between the substrate 456 and the substrate 454.

[0247] 17 illustrates bottom-gate transistors as the transistor 201 and the transistor 205. The transistor 201 and the transistor 205 each include a conductive layer 221 functioning as a gate electrode, an insulating layer 211 functioning as a gate insulating layer, a semiconductor layer 231, a conductive layer 222a and a conductive layer 222b functioning as a source electrode and a drain electrode, a conductive layer 223 functioning as a second gate electrode, and an insulating layer 213 functioning as a second gate insulating layer. The transistor is covered with an insulating layer 215.

[0248] The transistor 201 and the transistor 205 preferably include a metal oxide in the semiconductor layer 231 .

[0249] 17 is a lateral electric field type liquid crystal element. The liquid crystal element 480 has a pixel electrode 481, a common electrode 482, and a liquid crystal layer 483. The common electrode 482 is provided over the pixel electrode with an insulating layer 484 interposed therebetween. The liquid crystal layer 483 is provided over the pixel electrode 481 and the common electrode 482.

[0250] A color filter 452R, a color filter 452G, and a light-shielding layer BM are provided on the substrate 454 facing the substrate 456, and these are further covered with an overcoat 487. The color filter 452R and the color filter 452G transmit light of different colors.

[0251] An alignment film 485 and an alignment film 486 are provided in contact with the liquid crystal layer 483. The alignment film 485 is provided to cover the insulating layer 484 and the common electrode 482. The alignment film 486 is provided to cover the overcoat 487.

[0252] A backlight unit 491 is provided outside the substrate 456, and a polarizing plate 492 is provided between the substrate 456 and the backlight unit 491. In addition, a polarizing plate 493 is provided outside the substrate 454.

[0253] Light from the backlight unit 491 is emitted to the outside of the display device via the polarizer 492, substrate 456, pixel electrode 481, common electrode 482, liquid crystal layer 483, color filter 452R, polarizer 493, and substrate 454. The orientation of the liquid crystal is controlled according to the potential difference between the pixel electrode 481 and the common electrode 482, and the amount of transmitted light changes. Materials that transmit visible light are used for these layers through which the light from the backlight unit 491 passes.

[0254] Thermotropic liquid crystal, low molecular weight liquid crystal, polymer liquid crystal, polymer dispersed liquid crystal (PDLC), polymer network liquid crystal (PNLC), ferroelectric liquid crystal, antiferroelectric liquid crystal, etc. may be used for the liquid crystal layer 483. When the in-plane switching mode is adopted, liquid crystal exhibiting a blue phase without using an alignment film may also be used.

[0255] In addition, the liquid crystal element may be in a mode such as TN (Twisted Nematic) mode, VA (Vertical Alignment) mode, IPS (In-Plane-Switching) mode, FFS (Fringe Field Switching) mode, ASM (Axially Symmetrically Aligned Micro-cell) mode, OCB (Opticaly Compensated Birefringence) mode, ECB (Electrically Controlled Birefringence) mode, or guest-host mode.

[0256] Furthermore, a scattering type liquid crystal such as a polymer dispersed liquid crystal or a polymer network liquid crystal may be used for the liquid crystal layer 483. In this case, a configuration may be adopted in which black and white display is performed without providing a color filter 452R or the like, or a configuration may be adopted in which color display is performed by using a color filter 452R or the like.

[0257] Furthermore, a time-division display method (also called a field sequential driving method) that performs color display based on a time-division additive color mixture method may be applied as a driving method for the liquid crystal element. In this case, a configuration without the color filter 452R may be adopted. When the time-division display method is used, there is no need to provide sub-pixels that exhibit the respective colors of R (red), G (green), and B (blue), which has the advantage of improving the aperture ratio of the pixel and increasing the resolution.

[0258] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0259] Embodiment 5 In this embodiment, a light-emitting element (also referred to as a light-emitting device) that can be used for a display device included in an image processing system of one embodiment of the present invention will be described.

[0260] In this specification, etc., a device fabricated using a metal mask or an FMM (fine metal mask, high-resolution metal mask) may be referred to as a device with an MM (metal mask) structure. Also, in this specification, etc., a device fabricated without using a metal mask or an FMM may be referred to as a device with an MML (metal maskless) structure.

[0261] In this specification and the like, a structure in which different light-emitting layers are formed or different light-emitting layers are painted for each color light-emitting device (here, blue (B), green (G), and red (R)) may be referred to as an SBS (Side By Side) structure. In this specification and the like, a light-emitting device that can emit white light may be referred to as a white light-emitting device. In addition, a white light-emitting device can be combined with a colored layer (for example, a color filter) to form a light-emitting device for a display device that displays full color.

[0262] [Light-Emitting Device] Light-emitting devices can be broadly divided into single structures and tandem structures. A single-structure device has one light-emitting unit between a pair of electrodes. The light-emitting unit includes one or more light-emitting layers. To obtain white light emission with a single structure, light-emitting layers can be selected that can produce white light through the emission of each of two or more light-emitting layers. For example, by making the emission color of the first light-emitting layer and the emission color of the second light-emitting layer complementary to each other, a configuration can be obtained in which the light-emitting device as a whole emits white light. Furthermore, when white light emission is obtained using three or more light-emitting layers, the light-emitting device as a whole can emit white light by combining the emission colors of the three or more light-emitting layers.

[0263] A tandem-structure device has multiple light-emitting units between a pair of electrodes. Each light-emitting unit includes one or more light-emitting layers. By using light-emitting layers that emit light of the same color in each light-emitting unit, the brightness per given current can be increased, and the device can be made more reliable than a single-structure device. To obtain white light emission in a tandem structure, the light from the light-emitting layers of the multiple light-emitting units can be combined to obtain white light emission. The combination of light colors that can produce white light emission is the same as in the single-structure device. In a tandem-structure device, it is preferable to provide an intermediate layer, such as a charge-generating layer, between the multiple light-emitting units.

[0264] When comparing a white light-emitting device with a light-emitting device having an SBS structure, the light-emitting device with an SBS structure can consume less power than the white light-emitting device, and the manufacturing process of the white light-emitting device is simpler than that of the light-emitting device having an SBS structure, so the manufacturing cost can be lower and the manufacturing yield can be higher.

[0265] 18A , the light-emitting device has an EL layer 763 between a pair of electrodes (a lower electrode 761 and an upper electrode 762). The EL layer 763 can be composed of multiple layers such as a layer 780, a light-emitting layer 771, and a layer 790.

[0266] The light-emitting layer 771 contains at least a light-emitting substance (also referred to as a light-emitting material).

[0267] When the lower electrode 761 is an anode and the upper electrode 762 is a cathode, the layer 780 includes one or more of a layer containing a substance with high hole-injecting properties (hole-injecting layer), a layer containing a substance with high hole-transporting properties (hole-transporting layer), and a layer containing a substance with high electron-blocking properties (electron-blocking layer). The layer 790 also includes one or more of a layer containing a substance with high electron-injecting properties (electron-injecting layer), a layer containing a substance with high electron-transporting properties (electron-transporting layer), and a layer containing a substance with high hole-blocking properties (hole-blocking layer). When the lower electrode 761 is a cathode and the upper electrode 762 is an anode, the layers 780 and 790 have the opposite structures to those described above.

[0268] A structure including the layer 780, the light-emitting layer 771, and the layer 790 provided between a pair of electrodes can function as a single light-emitting unit, and the structure of FIG. 18A is referred to as a single structure in this specification.

[0269] 18B shows a modified example of the EL layer 763 included in the light-emitting device shown in Fig. 18A. Specifically, the light-emitting device shown in Fig. 18B includes a layer 781 on a lower electrode 761, a layer 782 on the layer 781, a light-emitting layer 771 on the layer 782, a layer 791 on the light-emitting layer 771, a layer 792 on the layer 791, and an upper electrode 762 on the layer 792.

[0270] When the lower electrode 761 is an anode and the upper electrode 762 is a cathode, for example, the layer 781 can be a hole injection layer, the layer 782 can be a hole transport layer, the layer 791 can be an electron transport layer, and the layer 792 can be an electron injection layer. When the lower electrode 761 is a cathode and the upper electrode 762 is an anode, the layer 781 can be an electron injection layer, the layer 782 can be an electron transport layer, the layer 791 can be a hole transport layer, and the layer 792 can be a hole injection layer. Such a layer structure allows carriers to be efficiently injected into the light-emitting layer 771, and the efficiency of carrier recombination in the light-emitting layer 771 can be increased.

[0271] 18C and 18D, a variation of the single structure is a configuration in which multiple light-emitting layers (light-emitting layers 771, 772, and 773) are provided between layer 780 and layer 790. While an example having three light-emitting layers is shown in FIGS. 18C and 18D, the number of light-emitting layers in a single-structure light-emitting device may be two, four, or more. Furthermore, a light-emitting device with a single structure may have a buffer layer between the two light-emitting layers.

[0272] 18E and 18F, a configuration in which a plurality of light-emitting units (light-emitting unit 763a and light-emitting unit 763b) are connected in series via a charge generation layer 785 (also referred to as an intermediate layer) is referred to as a tandem structure in this specification. Note that the tandem structure may also be referred to as a stack structure. By using a tandem structure, a light-emitting device capable of emitting light with high brightness can be obtained. Furthermore, compared to a single structure, the tandem structure can reduce the current required to obtain the same brightness, thereby improving reliability.

[0273] 18D and 18F are examples of display devices having a layer 764 overlapping with the light-emitting device. Fig. 18D is an example in which the layer 764 overlaps with the light-emitting device shown in Fig. 18C, and Fig. 18F is an example in which the layer 764 overlaps with the light-emitting device shown in Fig. 18E. In Fig. 18D and 18F, a conductive film that transmits visible light is used for the upper electrode 762 in order to extract light to the upper electrode 762 side.

[0274] The layer 764 can be a color conversion layer, a color filter (coloring layer), or both.

[0275] 18C and 18D , the light-emitting layers 771, 772, and 773 may be made of light-emitting materials that emit light of the same color, or even the same light-emitting material. For example, the light-emitting layers 771, 772, and 773 may be made of a light-emitting material that emits blue light. In the subpixel that emits blue light, blue light emitted by the light-emitting device can be extracted. In the subpixels that emit red light and the subpixels that emit green light, a color conversion layer can be provided as the layer 764 shown in FIG. 18D to convert blue light emitted by the light-emitting device into light with a longer wavelength, thereby extracting red or green light. It is preferable to use both a color conversion layer and a colored layer as the layer 764. A portion of the light emitted by the light-emitting device may be transmitted directly without being converted by the color conversion layer. By extracting the light that has passed through the color conversion layer through the colored layer, light other than the desired color can be absorbed by the colored layer, thereby improving the color purity of the light emitted by the subpixel.

[0276] 18C and 18D , light-emitting layers 771, 772, and 773 may each contain a light-emitting substance emitting light of a different color. White light can be obtained by appropriately combining the light emitted by light-emitting layers 771, 772, and 773. For example, a light-emitting device with a single structure preferably includes a light-emitting layer containing a light-emitting substance that emits blue light and a light-emitting layer containing a light-emitting substance that emits visible light with a wavelength longer than blue.

[0277] A color filter may be provided as layer 764 shown in Figure 18D. When white light passes through the color filter, light of a desired color can be obtained.

[0278] For example, when a light-emitting device with a single structure has three light-emitting layers, it preferably has a light-emitting layer containing a light-emitting material that emits red (R) light, a light-emitting layer containing a light-emitting material that emits green (G) light, and a light-emitting layer containing a light-emitting material that emits blue (B) light. The stacking order of the light-emitting layers may be R, G, B from the anode side, or R, B, G from the anode side, etc. In this case, a buffer layer may be provided between R and G or B.

[0279] Furthermore, for example, when a light-emitting device with a single structure has two light-emitting layers, a structure having one light-emitting layer containing a light-emitting substance that emits blue (B) light and another light-emitting layer containing a light-emitting substance that emits yellow (Y) light is preferred. This structure is sometimes referred to as a light-emitting device with a BY single structure.

[0280] 18C and 18D, the layer 780 and the layer 790 may each independently have a laminated structure made up of two or more layers, as shown in FIG. 18B.

[0281] 18E and 18F , the light-emitting layer 771 and the light-emitting layer 772 may be made of a light-emitting material that emits light of the same color, or even the same light-emitting material. For example, in a light-emitting device having subpixels that emit light of different colors, the light-emitting layer 771 and the light-emitting layer 772 may each be made of a light-emitting material that emits blue light. In the subpixel that emits blue light, the blue light emitted by the light-emitting device can be extracted. In the subpixel that emits red light and the subpixel that emits green light, a color conversion layer can be provided as the layer 764 shown in FIG. 18F to convert the blue light emitted by the light-emitting device into light with a longer wavelength, thereby allowing red or green light to be extracted. Furthermore, it is preferable to use both a color conversion layer and a colored layer as the layer 764.

[0282] Furthermore, when the light-emitting devices having the configurations shown in FIG. 18E or 18F are used for the subpixels emitting light of each color, different light-emitting materials may be used for each subpixel. Specifically, in a light-emitting device included in a subpixel emitting red light, light-emitting materials that emit red light may be used for the light-emitting layers 771 and 772, respectively. Similarly, in a light-emitting device included in a subpixel emitting green light, light-emitting materials that emit green light may be used for the light-emitting layers 771 and 772, respectively. In a light-emitting device included in a subpixel emitting blue light, light-emitting materials that emit blue light may be used for the light-emitting layers 771 and 772, respectively. A display device having such a configuration can be said to employ a tandem-structure light-emitting device and also have an SBS structure. Therefore, it can have the advantages of both the tandem structure and the SBS structure. This allows for a highly reliable light-emitting device capable of emitting high-brightness light.

[0283] 18E and 18F, light-emitting materials with different emission colors may be used for the light-emitting layer 771 and the light-emitting layer 772. When the light emitted from the light-emitting layer 771 and the light emitted from the light-emitting layer 772 are complementary colors, white light can be obtained. A color filter may be provided as the layer 764 shown in FIG. 18F. When white light passes through the color filter, light of a desired color can be obtained.

[0284] 18E and 18F show an example in which the light-emitting unit 763a has one light-emitting layer 771 and the light-emitting unit 763b has one light-emitting layer 772, but this is not limiting. Each of the light-emitting unit 763a and the light-emitting unit 763b may have two or more light-emitting layers.

[0285] 18E and 18F illustrate light-emitting devices having two light-emitting units, but the present invention is not limited to this. The light-emitting device may have three or more light-emitting units. Note that a configuration having two light-emitting units may be referred to as a two-tiered tandem structure, and a configuration having three light-emitting units may be referred to as a three-tiered tandem structure.

[0286] 18E and 18F, the light-emitting unit 763a includes a layer 780a, a light-emitting layer 771, and a layer 790a, and the light-emitting unit 763b includes a layer 780b, a light-emitting layer 772, and a layer 790b.

[0287] When the lower electrode 761 is an anode and the upper electrode 762 is a cathode, the layers 780a and 780b each have one or more of a hole injection layer, a hole transport layer, and an electron blocking layer. The layers 790a and 790b each have one or more of an electron injection layer, an electron transport layer, and a hole blocking layer. When the lower electrode 761 is a cathode and the upper electrode 762 is an anode, the layers 780a and 790a have the opposite structures to those described above, and the layers 780b and 790b also have the opposite structures to those described above.

[0288] When the lower electrode 761 is an anode and the upper electrode 762 is a cathode, for example, the layer 780a may have a hole injection layer, a hole transport layer on the hole injection layer, and an electron blocking layer on the hole transport layer. The layer 790a may have an electron transport layer and a hole blocking layer between the light-emitting layer 771 and the electron transport layer. The layer 780b may have a hole transport layer and an electron blocking layer on the hole transport layer. The layer 790b may have an electron transport layer, an electron injection layer on the electron transport layer, and a hole blocking layer between the light-emitting layer 772 and the electron transport layer. When the lower electrode 761 is a cathode and the upper electrode 762 is an anode, for example, the layer 780a may have an electron injection layer, an electron transport layer on the electron injection layer, and an electron blocking layer on the electron transport layer. Layer 790a has a hole transport layer and may further have an electron blocking layer between light-emitting layer 771 and the hole transport layer. Layer 780b has an electron transport layer and may further have a hole blocking layer on the electron transport layer. Layer 790b has a hole transport layer and a hole injection layer on the hole transport layer and may further have an electron blocking layer between light-emitting layer 772 and the hole transport layer.

[0289] When a light-emitting device having a tandem structure is fabricated, two light-emitting units are stacked via a charge generation layer 785. The charge generation layer 785 has at least a charge generation region. The charge generation layer 785 has a function of injecting electrons into one of the two light-emitting units and injecting holes into the other when a voltage is applied between a pair of electrodes.

[0290] An example of a light emitting device with a tandem structure is shown in FIGS. 19A to 19C.

[0291] 19A shows a configuration having three light-emitting units. In FIG. 19A , a plurality of light-emitting units (light-emitting unit 763a, light-emitting unit 763b, and light-emitting unit 763c) are connected in series via charge generation layers 785. Furthermore, light-emitting unit 763a includes layer 780a, light-emitting layer 771, and layer 790a. Light-emitting unit 763b includes layer 780b, light-emitting layer 772, and layer 790b. Light-emitting unit 763c includes layer 780c, light-emitting layer 773, and layer 790c. Note that layer 780c can have a structure applicable to layers 780a and 780b, and layer 790c can have a structure applicable to layers 790a and 790b.

[0292] 19A , the light-emitting layers 771, 772, and 773 preferably contain light-emitting materials that emit light of the same color. Specifically, the light-emitting layers 771, 772, and 773 may each contain a red (R) light-emitting material (a so-called R\R\R three-stage tandem structure), the light-emitting layers 771, 772, and 773 may each contain a green (G) light-emitting material (a so-called G\G\G three-stage tandem structure), or the light-emitting layers 771, 772, and 773 may each contain a blue (B) light-emitting material (a so-called B\B\B three-stage tandem structure). Note that "a\b" means that a light-emitting unit containing a light-emitting material that emits light of b is provided on a light-emitting unit containing a light-emitting material that emits light of a, via a charge-generating layer, and a and b represent colors.

[0293] 19A , light-emitting materials with different emission colors may be used for some or all of the light-emitting layers 771, 772, and 773. Examples of combinations of emission colors of the light-emitting layers 771, 772, and 773 include a configuration in which two of them are blue (B) and the remaining one is yellow (Y), and a configuration in which one of them is red (R), the other one is green (G), and the remaining one is blue (B).

[0294] Note that the light-emitting materials that emit light of the same color are not limited to the above configuration. For example, as shown in FIG. 19B , a tandem light-emitting device in which light-emitting units having multiple light-emitting layers are stacked may be used. FIG. 19B shows a configuration in which two light-emitting units (light-emitting unit 763a and light-emitting unit 763b) are connected in series via a charge generation layer 785. Furthermore, light-emitting unit 763a includes layer 780a, light-emitting layer 771a, light-emitting layer 771b, light-emitting layer 771c, and layer 790a. Light-emitting unit 763b includes layer 780b, light-emitting layer 772a, light-emitting layer 772b, light-emitting layer 772c, and layer 790b.

[0295] In FIG. 19B , light-emitting materials having complementary colors are selected for the light-emitting layers 771a, 771b, and 771c, and the light-emitting unit 763a is configured to emit white light (W). Light-emitting materials having complementary colors are also selected for the light-emitting layers 772a, 772b, and 772c, and the light-emitting unit 763b is configured to emit white light (W). That is, the structure shown in FIG. 19B is a two-tiered W / W tandem structure. The stacking order of the light-emitting materials having complementary colors is not particularly limited. The implementer can select the optimal stacking order as appropriate. Although not shown, a three-tiered W / W / W tandem structure or a four-tiered or more tandem structure may also be used.

[0296] In addition, when a light-emitting device with a tandem structure is used, there are a B\Y or Y\B two-stage tandem structure having a light-emitting unit that emits yellow (Y) light and a light-emitting unit that emits blue (B) light, a R.G\B or B\R.G two-stage tandem structure having a light-emitting unit that emits red (R) and green (G) light and a light-emitting unit that emits blue (B) light, a light-emitting unit that emits yellow (Y) light and a light-emitting unit that emits blue (B) light, and a light-emitting unit that emits blue (B) light. Examples of such a tandem structure include a B\Y\B three-stage tandem structure having, in this order, a light-emitting unit that emits blue (B) light, a light-emitting unit that emits yellow-green (YG) light, and a light-emitting unit that emits blue (B) light, and a B\G\B three-stage tandem structure having, in this order, a light-emitting unit that emits blue (B) light, a light-emitting unit that emits green (G) light, and a light-emitting unit that emits blue (B) light. Note that "a·b" means that one light-emitting unit has a light-emitting substance that emits light of a and a light-emitting substance that emits light of b.

[0297] Furthermore, as shown in FIG. 19C, a light-emitting unit having one light-emitting layer and a light-emitting unit having multiple light-emitting layers may be combined.

[0298] 19C , a plurality of light-emitting units (light-emitting unit 763a, light-emitting unit 763b, and light-emitting unit 763c) are connected in series via charge generation layers 785. Light-emitting unit 763a includes a layer 780a, a light-emitting layer 771, and a layer 790a. Light-emitting unit 763b includes a layer 780b, a light-emitting layer 772a, a light-emitting layer 772b, a light-emitting layer 772c, and a layer 790b. Light-emitting unit 763c includes a layer 780c, a light-emitting layer 773, and a layer 790c.

[0299] For example, in the configuration shown in Figure 19C, a three-stage tandem structure of B\R·G·YG\B can be applied, in which light-emitting unit 763a is a light-emitting unit that emits blue (B) light, light-emitting unit 763b is a light-emitting unit that emits red (R), green (G), and yellow-green (YG) light, and light-emitting unit 763c is a light-emitting unit that emits blue (B) light.

[0300] For example, the number of layers of the light-emitting units and the order of the colors can be, from the anode side, a two-layer structure of B and Y, a two-layer structure of B and light-emitting unit X, a three-layer structure of B, Y, and B, and the number of layers of the light-emitting layers in light-emitting unit X and the order of the colors can be, from the anode side, a two-layer structure of R and Y, a two-layer structure of R and G, a two-layer structure of G and R, a three-layer structure of G, R, and G, or a three-layer structure of R, G, and R. Furthermore, another layer can be provided between the two light-emitting layers.

[0301] Next, materials that can be used in light-emitting devices will be described.

[0302] Of the lower electrode 761 and the upper electrode 762, a conductive film that transmits visible light is used for the electrode from which light is extracted. A conductive film that reflects visible light is preferably used for the electrode from which light is not extracted. When the display device has a light-emitting device that emits infrared light, a conductive film that transmits visible light and infrared light is preferably used for the electrode from which light is extracted, and a conductive film that reflects visible light and infrared light is preferably used for the electrode from which light is not extracted.

[0303] A conductive film that transmits visible light may also be used for the electrode on the side from which light is not extracted. In this case, the electrode is preferably disposed between the reflective layer and the EL layer 763. That is, light emitted from the EL layer 763 may be reflected by the reflective layer and extracted from the display device.

[0304] Materials for forming the pair of electrodes of a light-emitting device can include metals, alloys, electrically conductive compounds, and mixtures thereof. Specific examples of such materials include metals such as aluminum, magnesium, titanium, chromium, manganese, iron, cobalt, nickel, copper, gallium, zinc, indium, tin, molybdenum, tantalum, tungsten, palladium, gold, platinum, silver, yttrium, and neodymium, as well as alloys containing these metals in combination. Examples of such materials include indium tin oxide (In-Sn oxide, also referred to as ITO), In-Si-Sn oxide (also referred to as ITSO), indium zinc oxide (In-Zn oxide), and In-W-Zn oxide. Examples of such materials include aluminum alloys, such as an aluminum-nickel-lanthanum alloy (Al-Ni-La), and silver-magnesium alloys and silver-palladium-copper alloys (Ag-Pd-Cu, also referred to as APC). Other examples of the material include elements belonging to Group 1 or 2 of the periodic table (e.g., lithium, cesium, calcium, and strontium) that are not listed above as examples, rare earth metals such as europium and ytterbium, alloys containing appropriate combinations of these, and graphene.

[0305] The light-emitting device preferably has a micro-optical resonator (microcavity) structure. Therefore, one of a pair of electrodes of the light-emitting device preferably has a transmissive and reflective electrode for visible light, and the other preferably has a reflective electrode for visible light. By having the light-emitting device have a microcavity structure, the light emitted from the light-emitting layer can be resonated between the two electrodes, thereby intensifying the light emitted from the light-emitting device.

[0306] The semi-transmitting / semi-reflective electrode can have a stacked structure of a conductive layer that can be used as a reflective electrode and a conductive layer that can be used as an electrode that is transparent to visible light (also referred to as a transparent electrode).

[0307] The light transmittance of the transparent electrode is 40% or more. For example, it is preferable to use an electrode having a visible light (light with a wavelength of 400 nm or more and less than 750 nm) transmittance of 40% or more for the transparent electrode of a light-emitting device. The visible light reflectance of the semi-transmissive / semi-reflective electrode is 10% or more and 95% or less, preferably 30% or more and 80% or less. The visible light reflectance of the reflective electrode is 40% or more and 100% or less, preferably 70% or more and 100% or less. The resistivity of these electrodes is 1×10 −２ Preferably, it is Ωcm or less.

[0308] The light-emitting device has at least a light-emitting layer. The light-emitting device may further have, as a layer other than the light-emitting layer, a layer containing a substance with high hole-injection properties, a substance with high hole-transport properties, a hole-blocking material, a substance with high electron-transport properties, an electron-blocking material, a substance with high electron-injection properties, or a bipolar substance (a substance with high electron-transport properties and high hole-transport properties). For example, the light-emitting device may have, in addition to the light-emitting layer, one or more layers selected from a hole-injection layer, a hole-transport layer, a hole-blocking layer, a charge-generating layer, an electron-blocking layer, an electron-transport layer, and an electron-injection layer.

[0309] The light-emitting device can be made of either a low-molecular-weight compound or a high-molecular-weight compound, and may contain an inorganic compound. The layers constituting the light-emitting device can be formed by a method such as vapor deposition (including vacuum vapor deposition), transfer, printing, inkjet printing, or coating.

[0310] The light-emitting layer contains one or more light-emitting materials. As the light-emitting material, a material that emits light of blue, purple, blue-purple, green, yellow-green, yellow, orange, red, or the like is appropriately used. Furthermore, a material that emits near-infrared light can also be used as the light-emitting material.

[0311] The light-emitting material may include a fluorescent material, a phosphorescent material, a TADF material, and a quantum dot material.

[0312] Examples of fluorescent materials include pyrene derivatives, anthracene derivatives, triphenylene derivatives, fluorene derivatives, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, dibenzoquinoxaline derivatives, quinoxaline derivatives, pyridine derivatives, pyrimidine derivatives, phenanthrene derivatives, and naphthalene derivatives.

[0313] Examples of phosphorescent materials include organometallic complexes (particularly iridium complexes) having a 4H-triazole skeleton, a 1H-triazole skeleton, an imidazole skeleton, a pyrimidine skeleton, a pyrazine skeleton, or a pyridine skeleton; organometallic complexes (particularly iridium complexes) having a phenylpyridine derivative having an electron-withdrawing group as a ligand; platinum complexes; and rare earth metal complexes.

[0314] The light-emitting layer may contain one or more organic compounds (host material, assist material, etc.) in addition to the light-emitting substance (guest material). As the one or more organic compounds, one or both of a substance with high hole transport properties (hole transport material) and a substance with high electron transport properties (electron transport material) can be used. As the hole-transporting material, a material with high hole transport properties that can be used for the hole-transporting layer, which will be described later, can be used. As the electron-transporting material, a material with high electron transport properties that can be used for the electron-transporting layer, which will be described later, can be used. Furthermore, as the one or more organic compounds, a bipolar material or a TADF material may be used.

[0315] The light-emitting layer preferably includes, for example, a phosphorescent material and a hole-transporting material and an electron-transporting material that are a combination that easily forms an exciplex. This configuration allows for efficient emission using Exciplex-Triple Energy Transfer (ExTET), which is energy transfer from the exciplex to the light-emitting material (phosphorescent material). By selecting a combination that forms an exciplex that emits light that overlaps with the wavelength of the lowest-energy absorption band of the light-emitting material, energy transfer becomes smooth, allowing for efficient emission. This configuration simultaneously enables high efficiency, low-voltage operation, and long life of the light-emitting device.

[0316] The hole injection layer is a layer that injects holes from the anode into the hole transport layer and contains a material with high hole injection properties, such as an aromatic amine compound and a composite material containing a hole transport material and an acceptor material (electron acceptor material).

[0317] As the hole transporting material, a material having high hole transporting properties that can be used for the hole transport layer, which will be described later, can be used.

[0318] Examples of the acceptor material include oxides of metals belonging to Groups 4 to 8 of the periodic table. Specific examples include molybdenum oxide, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, tungsten oxide, manganese oxide, and rhenium oxide. Among these, molybdenum oxide is particularly preferred because it is stable in the atmosphere, has low hygroscopicity, and is easy to handle. Alternatively, organic acceptor materials containing fluorine can be used. Other organic acceptor materials that can be used include quinodimethane derivatives, chloranil derivatives, and hexaazatriphenylene derivatives.

[0319] For example, as a material with high hole injection properties, a material containing a hole transporting material and an oxide of a metal belonging to Groups 4 to 8 of the periodic table (typically, molybdenum oxide) may be used.

[0320] The hole transport layer is a layer that transports holes injected from the anode by the hole injection layer to the light emitting layer. The hole transport layer is a layer that contains a hole transport material. The hole transport material is a material having a concentration of 1×10 −６ cm ２ A substance having a hole mobility of 1 / Vs or more is preferred. Note that other substances can also be used as long as they have a higher hole transporting property than electron transporting property. As the hole transporting material, a material having a high hole transporting property, such as a π-electron-rich heteroaromatic compound (e.g., a carbazole derivative, a thiophene derivative, a furan derivative, etc.) or an aromatic amine (a compound having an aromatic amine skeleton), is preferred.

[0321] The electron blocking layer is provided in contact with the light-emitting layer. The electron blocking layer is a layer containing a material that has hole transport properties and can block electrons. The electron blocking layer can be made of a material that has electron blocking properties among the hole transport materials described above.

[0322] The electron blocking layer has hole transport properties and can therefore also be called a hole transport layer. Furthermore, a layer of the hole transport layer that has electron blocking properties can also be called an electron blocking layer.

[0323] The electron transport layer is a layer that transports electrons injected from the cathode by the electron injection layer to the light emitting layer. The electron transport layer is a layer that contains an electron transporting material. The electron transporting material is a material having a molecular weight of 1×10 −６ cm ２ A substance having an electron mobility of 1 / Vs or more is preferred. Note that other substances can also be used as long as they have a higher electron transporting property than holes. Examples of electron-transporting materials that can be used include metal complexes having a quinoline skeleton, metal complexes having a benzoquinoline skeleton, metal complexes having an oxazole skeleton, and metal complexes having a thiazole skeleton, as well as oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxazole derivatives, thiazole derivatives, phenanthroline derivatives, quinoline derivatives having a quinoline ligand, benzoquinoline derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, and other π-electron-deficient heteroaromatic compounds including nitrogen-containing heteroaromatic compounds.

[0324] The hole-blocking layer is provided in contact with the light-emitting layer. The hole-blocking layer is a layer containing a material that has electron transport properties and can block holes. The hole-blocking layer can be made of a material that has hole-blocking properties and is selected from the above electron-transporting materials.

[0325] The hole blocking layer has electron transport properties and can therefore also be called an electron transport layer. Furthermore, a layer of the electron transport layer that has hole blocking properties can also be called a hole blocking layer.

[0326] The electron injection layer is a layer that injects electrons from the cathode to the electron transport layer and contains a material with high electron injection properties. Examples of the material with high electron injection properties include alkali metals, alkaline earth metals, and compounds thereof. Examples of the material with high electron injection properties include a composite material containing an electron transport material and a donor material (electron donor material).

[0327] Furthermore, it is preferable that the LUMO level of a material with high electron injection properties has a small difference (specifically, 0.5 eV or less) from the work function value of the material used for the cathode.

[0328] The electron injection layer may contain, for example, lithium, cesium, ytterbium, lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF ｘ , where X is an arbitrary number), 8-(quinolinolato)lithium (abbreviation: Liq), 2-(2-pyridyl)phenolatolithium (abbreviation: LiPP), 2-(2-pyridyl)-3-pyridinolatolithium (abbreviation: LiPPy), 4-phenyl-2-(2-pyridyl)phenolatolithium (abbreviation: LiPPP), lithium oxide (LiO ｘ ), alkali metals such as cesium carbonate, alkaline earth metals, or compounds thereof can be used. The electron injection layer may have a stacked structure of two or more layers. For example, the stacked structure may have a structure in which lithium fluoride is used as the first layer and ytterbium is provided as the second layer.

[0329] The electron injection layer may contain an electron transporting material. For example, a compound having an unshared electron pair and an electron-deficient heteroaromatic ring can be used as the electron transporting material. Specifically, a compound having at least one of a pyridine ring, a diazine ring (pyrimidine ring, pyrazine ring, pyridazine ring), and a triazine ring can be used.

[0330] The lowest unoccupied molecular orbital (LUMO) level of an organic compound having an unshared electron pair is preferably −3.6 eV or more and −2.3 eV or less. Generally, the highest occupied molecular orbital (HOMO) level and the LUMO level of an organic compound can be estimated by CV (cyclic voltammetry), photoelectron spectroscopy, optical absorption spectroscopy, inverse photoelectron spectroscopy, or the like.

[0331] For example, 4,7-diphenyl-1,10-phenanthroline (abbreviation: BPhen), 2,9-di(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBPhen), diquinoxalino[2,3-a:2',3'-c]phenazine (abbreviation: HATNA), 2,4,6-tris[3'-(pyridin-3-yl)biphenyl-3-yl]-1,3,5-triazine (abbreviation: TmPPPyTz), etc. can be used as the organic compound having an unshared electron pair. Note that NBPhen has a higher glass transition point (Tg) and is superior in heat resistance compared to BPhen.

[0332] As described above, the charge generation layer has at least a charge generation region. The charge generation region preferably contains an acceptor material, for example, a hole transport material and an acceptor material applicable to the hole injection layer.

[0333] The charge generation layer preferably includes a layer containing a material with high electron injection properties. This layer may also be called an electron injection buffer layer. The electron injection buffer layer is preferably provided between the charge generation region and the electron transport layer. By providing the electron injection buffer layer, the injection barrier between the charge generation region and the electron transport layer can be alleviated, so that electrons generated in the charge generation region can be easily injected into the electron transport layer.

[0334] The electron injection buffer layer preferably contains an alkali metal or an alkaline earth metal, and may contain, for example, an alkali metal compound or an alkaline earth metal compound. Specifically, the electron injection buffer layer preferably contains an inorganic compound containing an alkali metal and oxygen, or an inorganic compound containing an alkaline earth metal and oxygen, and may contain an inorganic compound containing lithium and oxygen (lithium oxide (Li ２ In addition, the electron injection buffer layer can be suitably made of the materials applicable to the electron injection layer described above.

[0335] The charge generation layer preferably has a layer containing a material with high electron transport properties. This layer can also be called an electron relay layer. The electron relay layer is preferably provided between the charge generation region and the electron injection buffer layer. When the charge generation layer does not have an electron injection buffer layer, the electron relay layer is preferably provided between the charge generation region and the electron transport layer. The electron relay layer has the function of preventing interaction between the charge generation region and the electron injection buffer layer (or the electron transport layer) and smoothly transferring electrons.

[0336] For the electron relay layer, it is preferable to use a phthalocyanine-based material such as copper (II) phthalocyanine (abbreviated as CuPc) or a metal complex having a metal-oxygen bond and an aromatic ligand.

[0337] It should be noted that the charge generation region, electron injection buffer layer, and electron relay layer may not be clearly distinguishable from one another depending on their cross-sectional shapes or characteristics.

[0338] The charge generation layer may contain a donor material instead of an acceptor material. For example, the charge generation layer may contain a layer containing an electron transport material and a donor material that can be used for the electron injection layer.

[0339] When light-emitting units are stacked, an increase in driving voltage can be suppressed by providing a charge generating layer between two light-emitting units.

[0340] This embodiment mode can be combined with other embodiment modes as appropriate.

[0341] At least a part of the configuration examples exemplified in this embodiment and the corresponding drawings can be combined as appropriate with other configuration examples or drawings.

[0342] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0343] Embodiment 6 In this embodiment, a light-receiving device that can be used for a display device of one embodiment of the present invention and a display device having a light-receiving and light-emitting function will be described.

[0344] The light receiving device may be, for example, a pn-type or pin-type photodiode. The light receiving device functions as a photoelectric conversion device (also called a photoelectric conversion element) that detects light incident on the light receiving device and generates electric charges. The amount of electric charges generated by the light receiving device is determined based on the amount of light incident on the light receiving device.

[0345] In particular, it is preferable to use an organic photodiode having a layer containing an organic compound as the light-receiving device. Organic photodiodes can be easily made thin, lightweight, and large in area, and have a high degree of freedom in shape and design, making them applicable to a variety of display devices.

[0346] 20A, the light-receiving device has a layer 765 between a pair of electrodes (a lower electrode 761 and an upper electrode 762). The layer 765 has at least one active layer and may further have other layers.

[0347] 20B shows a modification of the layer 765 included in the light-receiving device shown in Fig. 20A. Specifically, the light-receiving device shown in Fig. 20B includes a layer 766 on a lower electrode 761, an active layer 767 on the layer 766, a layer 768 on the active layer 767, and an upper electrode 762 on the layer 768.

[0348] The active layer 767 functions as a photoelectric conversion layer.

[0349] When the lower electrode 761 is an anode and the upper electrode 762 is a cathode, the layer 766 includes a hole transport layer and / or an electron blocking layer. The layer 768 includes an electron transport layer and / or a hole blocking layer. When the lower electrode 761 is a cathode and the upper electrode 762 is an anode, the layers 766 and 768 have the reversed structures.

[0350] Here, in a display device according to one embodiment of the present invention, a layer shared by the light-receiving device and the light-emitting device (which may also be referred to as a continuous layer shared by the light-receiving device and the light-emitting device) may be present. Such a layer may have different functions in the light-emitting device and the light-receiving device. In this specification, components may be referred to based on their functions in the light-emitting device. For example, a hole injection layer functions as a hole injection layer in the light-emitting device and as a hole transport layer in the light-receiving device. Similarly, an electron injection layer functions as an electron injection layer in the light-emitting device and as an electron transport layer in the light-receiving device. Furthermore, a layer shared by the light-receiving device and the light-emitting device may have the same function in the light-emitting device and in the light-receiving device. For example, a hole transport layer functions as a hole transport layer in both the light-emitting device and the light-receiving device, and an electron transport layer functions as an electron transport layer in both the light-emitting device and the light-receiving device.

[0351] Next, materials that can be used for the light-receiving device will be described.

[0352] The light-receiving device may be made of either a low-molecular-weight compound or a high-molecular-weight compound, and may contain an inorganic compound. The layers constituting the light-receiving device may be formed by a method such as vapor deposition (including vacuum deposition), transfer, printing, inkjet printing, or coating.

[0353] The active layer of the light-receiving device includes a semiconductor. Examples of the semiconductor include inorganic semiconductors such as silicon and organic semiconductors containing organic compounds. In this embodiment, an example in which an organic semiconductor is used as the semiconductor of the active layer is shown. Using an organic semiconductor is preferable because the light-emitting layer and the active layer can be formed by the same method (e.g., vacuum deposition), allowing the use of a common manufacturing device.

[0354] The n-type semiconductor material of the active layer is fullerene (e.g., C ６０ Fullerene, C ７０ Examples of the fullerene derivatives include [6,6]-phenyl-C ７１ -Butyric acid methyl ester (abbreviation: PC71BM), [6,6]-phenyl-C ６１ -butyric acid methyl ester (abbreviation: PC61BM), 1',1'',4',4''-tetrahydro-di[1,4]methanonaphthaleno[1,2:2',3',56,60:2'',3''][5,6]fullerene-C ６０ (abbreviation: ICBA) and others.

[0355] Examples of materials for n-type semiconductors include perylene tetracarboxylic acid derivatives such as N,N′-dimethyl-3,4,9,10-perylene tetracarboxylic acid diimide (abbreviation: Me-PTCDI), and 2,2′-(5,5′-(thieno[3,2-b]thiophene-2,5-diyl)bis(thiophene-5,2-diyl))bis(methane-1-yl-1-ylidene)dimalononitrile (abbreviation: FT2TDMN).

[0356] Examples of n-type semiconductor materials include metal complexes having a quinoline skeleton, metal complexes having a benzoquinoline skeleton, metal complexes having an oxazole skeleton, metal complexes having a thiazole skeleton, oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxazole derivatives, thiazole derivatives, phenanthroline derivatives, quinoline derivatives, benzoquinoline derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, naphthalene derivatives, anthracene derivatives, coumarin derivatives, rhodamine derivatives, triazine derivatives, and quinone derivatives.

[0357] Examples of the p-type semiconductor material of the active layer include electron-donating organic semiconductor materials such as copper(II) phthalocyanine (abbreviation: CuPc), tetraphenyldibenzoperiflanthene (abbreviation: DBP), zinc phthalocyanine (abbreviation: ZnPc), tin(II) phthalocyanine (abbreviation: SnPc), quinacridone, and rubrene.

[0358] Examples of p-type semiconductor materials include carbazole derivatives, thiophene derivatives, furan derivatives, compounds having an aromatic amine skeleton, etc. Examples of p-type semiconductor materials include naphthalene derivatives, anthracene derivatives, pyrene derivatives, triphenylene derivatives, fluorene derivatives, pyrrole derivatives, benzofuran derivatives, benzothiophene derivatives, indole derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, indolocarbazole derivatives, porphyrin derivatives, phthalocyanine derivatives, naphthalocyanine derivatives, quinacridone derivatives, rubrene derivatives, tetracene derivatives, polyphenylenevinylene derivatives, polyparaphenylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, and polythiophene derivatives.

[0359] The HOMO level of the electron-donating organic semiconductor material is preferably shallower (higher) than the HOMO level of the electron-accepting organic semiconductor material, and the LUMO level of the electron-donating organic semiconductor material is preferably shallower (higher) than the LUMO level of the electron-accepting organic semiconductor material.

[0360] It is preferable to use a spherical fullerene as the electron-accepting organic semiconductor material and a planar organic semiconductor material as the electron-donating organic semiconductor material. Molecules with similar shapes tend to aggregate together, and when molecules of the same type aggregate, the energy levels of their molecular orbitals become close, which can improve carrier transport properties.

[0361] Furthermore, a polymer compound such as poly[[4,8-bis[5-(2-ethylhexyl)-2-thienyl]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl]-2,5-thiophenediyl[5,7-bis(2-ethylhexyl)-4,8-dioxo-4H,8H-benzo[1,2-c:4,5-c']dithiophene-1,3-diyl]] polymer (abbreviated as PBDB-T) or a PBDB-T derivative, which functions as a donor, can be used in the active layer. For example, a method of dispersing an acceptor material in PBDB-T or a PBDB-T derivative can be used.

[0362] For example, the active layer is preferably formed by co-evaporating an n-type semiconductor and a p-type semiconductor, or may be formed by laminating an n-type semiconductor and a p-type semiconductor.

[0363] The active layer may also contain a mixture of three or more materials. For example, in order to broaden the wavelength range, a third material may be mixed in addition to an n-type semiconductor material and a p-type semiconductor material. In this case, the third material may be a low-molecular-weight compound or a high-molecular-weight compound.

[0364] The light-receiving device may further include a layer containing a substance with high hole-transporting properties, a substance with high electron-transporting properties, or a bipolar substance (a substance with high electron-transporting properties and high hole-transporting properties) as a layer other than the active layer. Furthermore, without being limited to the above, the light-receiving device may further include a layer containing a substance with high hole-injecting properties, a hole-blocking material, a material with high electron-injecting properties, or an electron-blocking material. For the layer other than the active layer of the light-receiving device, for example, the materials that can be used in the above-mentioned light-emitting device can be used.

[0365] For example, the hole transport material or electron blocking material may be a polymer compound such as poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (PEDOT / PSS), or an inorganic compound such as molybdenum oxide or copper iodide (CuI). The electron transport material or hole blocking material may be an inorganic compound such as zinc oxide (ZnO), or an organic compound such as polyethyleneimine ethoxylate (PEIE). The light-receiving device may have, for example, a mixed film of PEIE and ZnO.

[0366] [Display Device Having Light Detection Function] In a display device according to one embodiment of the present invention, light-emitting devices are arranged in a matrix in a display portion, and an image can be displayed on the display portion. Furthermore, light-receiving devices are arranged in a matrix in the display portion, and the display portion has one or both of an imaging function and a sensing function in addition to an image display function. The display portion can be used as an image sensor or a touch sensor. That is, by detecting light in the display portion, an image can be captured or the proximity or contact of an object (such as a finger, a hand, or a pen) can be detected.

[0367] Furthermore, in the display device of one embodiment of the present invention, the light-emitting device can be used as a light source for a sensor. In the display device of one embodiment of the present invention, when light emitted from the light-emitting device included in the display portion is reflected (or scattered) by an object, the light-receiving device can detect the reflected light (or scattered light), thereby enabling imaging or touch detection even in a dark place.

[0368] Therefore, a light receiving unit and a light source are not required to be provided separately from the display device, and the number of components in the electronic device can be reduced. For example, a biometric authentication device or a capacitive touch panel for scrolling or the like is not required to be provided separately in the electronic device. Therefore, by using the display device of one embodiment of the present invention, an electronic device with reduced manufacturing costs can be provided.

[0369] Specifically, a display device according to one embodiment of the present invention has a light-emitting device and a light-receiving device in each pixel. In the display device according to one embodiment of the present invention, an organic EL device is used as the light-emitting device, and an organic photodiode is used as the light-receiving device. The organic EL device and the organic photodiode can be formed on the same substrate. Therefore, the organic photodiode can be built into a display device using an organic EL device.

[0370] In a display device having a light-emitting device and a light-receiving device in each pixel, the pixel has a light-receiving function, so that it is possible to detect contact or proximity of an object while displaying an image. For example, in addition to displaying an image using all of the sub-pixels of the display device, some of the sub-pixels can emit light as a light source and the remaining sub-pixels can display an image.

[0371] When the light receiving device is used as an image sensor, the display device can capture an image using the light receiving device. For example, the display device of the present embodiment can be used as a scanner.

[0372] For example, an image sensor can be used to capture images for personal authentication using fingerprints, palm prints, irises, pulse patterns (including vein patterns and arterial patterns), faces, or the like.

[0373] For example, an image sensor can be used to capture images of the area around the eye, the surface of the eye, or the inside of the eye (such as the fundus) of a user of a wearable device. Therefore, the wearable device can have a function to detect one or more of the user's blinking, movement of the pupil, and movement of the eyelid.

[0374] The light receiving device can also be used as a touch sensor (also called a direct touch sensor) or a near-touch sensor (also called a hover sensor, hover touch sensor, non-contact sensor, or touchless sensor).

[0375] Here, the touch sensor or near-touch sensor can detect the proximity or contact of an object (such as a finger, hand, or pen).

[0376] A touch sensor can detect an object when the display device and the object are in direct contact with each other. A near-touch sensor can detect an object even if the object does not touch the display device. For example, a configuration in which the display device can detect an object when the distance between the display device and the object is between 0.1 mm and 300 mm, preferably between 3 mm and 50 mm, is preferred. This configuration allows the display device to be operated without the object directly touching it, in other words, it allows the display device to be operated in a non-contact (touchless) manner. This configuration reduces the risk of the display device becoming dirty or scratched, or allows the object to operate the display device without directly touching dirt (e.g., dust, viruses, etc.) attached to the display device.

[0377] Furthermore, the display device of one embodiment of the present invention can have a variable refresh rate. For example, the refresh rate can be adjusted (for example, adjusted within a range of 1 Hz to 240 Hz) depending on the content displayed on the display device to reduce power consumption. Furthermore, the drive frequency of the touch sensor or the near-touch sensor may be changed depending on the refresh rate. For example, when the refresh rate of the display device is 120 Hz, the drive frequency of the touch sensor or the near-touch sensor can be configured to be higher than 120 Hz (typically 240 Hz). This configuration enables low power consumption and an increased response speed of the touch sensor or the near-touch sensor.

[0378] The display device 100 shown in FIGS. 20C to 20E includes, between a substrate 351 and a substrate 359, a layer 353 having a light-receiving device, a functional layer 355, and a layer 357 having a light-emitting device.

[0379] The functional layer 355 has a circuit for driving the light-receiving device and a circuit for driving the light-emitting device. The functional layer 355 may be provided with one or more of a switch, a transistor, a capacitor, a resistor, a wiring, a terminal, etc. Note that when the light-emitting device and the light-receiving device are driven by a passive matrix method, a configuration without a switch or a transistor may be used.

[0380] 20C , light emitted by a light-emitting device in layer 357 having a light-emitting device is reflected by finger 352 that touches display device 100, and the reflected light is detected by a light-receiving device in layer 353 having a light-receiving device. This makes it possible to detect that finger 352 has touched display device 100.

[0381] 20D and 20E, the display device may have a function of detecting or capturing an object that is close to (not in contact with) the display device. Fig. 20D shows an example of detecting a person's finger, and Fig. 20E shows an example of detecting information about the periphery, surface, or interior of a person's eye (such as the number of blinks, eyeball movement, and eyelid movement).

[0382] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0383] In this embodiment, a structural example of a transistor that can be applied to a display device (display panel) of one embodiment of the present invention will be described. In particular, the case where a transistor containing silicon as a semiconductor in which a channel is formed will be described.

[0384] One embodiment of the present invention is a display panel including a light-emitting device and a pixel circuit. The display panel can achieve a full-color display panel by including, for example, three types of light-emitting devices (also referred to as light-emitting elements) that emit red (R), green (G), and blue (B) light, respectively.

[0385] It is preferable that all transistors included in a pixel circuit that drives a light-emitting device be transistors having silicon in a semiconductor layer where a channel is formed. Examples of silicon include single crystal silicon, polycrystalline silicon, and amorphous silicon. In particular, it is preferable to use a transistor having low temperature polysilicon (LTPS) in the semiconductor layer (hereinafter also referred to as an LTPS transistor). LTPS transistors have high field-effect mobility and good frequency characteristics.

[0386] By using silicon transistors such as LTPS transistors, circuits that need to be driven at high frequencies (such as source driver circuits) can be built on the same substrate as the display unit, which simplifies the external circuits mounted on the display panel and reduces component and mounting costs.

[0387] At least one of the transistors included in the pixel circuit preferably includes a transistor (hereinafter also referred to as an OS transistor) having a metal oxide (hereinafter also referred to as an oxide semiconductor) as a semiconductor in which a channel is formed. The OS transistor has significantly higher field-effect mobility than a transistor using amorphous silicon. Furthermore, the OS transistor has significantly lower source-drain leakage current in an off state (hereinafter also referred to as an off-state current), and can retain charge accumulated in a capacitor connected in series with the OS transistor for a long period of time. Furthermore, the use of an OS transistor can reduce the power consumption of a display panel.

[0388] By using LTPS transistors for some of the transistors included in a pixel circuit and OS transistors for the other transistors, a display panel with low power consumption and high driving capability can be realized. As a more preferred example, it is preferable to use OS transistors as transistors that function as switches for controlling conduction / non-conduction between wirings and LTPS transistors as transistors that control current.

[0389] For example, one of the transistors provided in the pixel circuit functions as a transistor for controlling a current flowing through a light-emitting device and can be called a driving transistor. One of the source and drain of the driving transistor is electrically connected to a pixel electrode of the light-emitting device. It is preferable to use an LTPS transistor as the driving transistor. This allows the current flowing through the light-emitting device in the pixel circuit to be increased.

[0390] On the other hand, another transistor provided in the pixel circuit functions as a switch for controlling pixel selection / non-selection and can also be called a selection transistor. The gate of the selection transistor is electrically connected to a gate line, and one of the source and drain is electrically connected to a source line (signal line). It is preferable to use an OS transistor as the selection transistor. This allows the gradation of a pixel to be maintained even when the frame frequency is significantly reduced (for example, 1 fps or less), and therefore power consumption can be reduced by stopping the driver when displaying a still image.

[0391] A more specific configuration example will be described below with reference to the drawings.

[0392] 21A shows a block diagram of a display panel 500. The display panel 500 includes a display portion 504, a driver circuit portion 502, a driver circuit portion 503, and the like.

[0393] The display unit 504 has a plurality of pixels 530 arranged in a matrix. Each pixel 530 has sub-pixels 505R, 505G, and 505B. Each of the sub-pixels 505R, 505G, and 505B has a light-emitting device that functions as a display device.

[0394] The pixel 530 is electrically connected to a wiring GL, a wiring SLR, a wiring SLG, and a wiring SLB. The wirings SLR, SLG, and SLB are each electrically connected to a driver circuit unit 502. The wiring GL is electrically connected to a driver circuit unit 503. The driver circuit unit 502 functions as a source line driver circuit (also referred to as a source driver), and the driver circuit unit 503 functions as a gate line driver circuit (also referred to as a gate driver). The wiring GL functions as a gate line, and the wirings SLR, SLG, and SLB function as source lines.

[0395] The sub-pixel 505R has a light-emitting device that emits red light. The sub-pixel 505G has a light-emitting device that emits green light. The sub-pixel 505B has a light-emitting device that emits blue light. This allows the display panel 500 to display full color. Note that the pixel 530 may also have sub-pixels that have light-emitting devices that emit light of other colors. For example, in addition to the above three sub-pixels, the pixel 530 may also have a sub-pixel that has a light-emitting device that emits white light or a sub-pixel that has a light-emitting device that emits yellow light.

[0396] The wiring GL is electrically connected to the sub-pixels 505R, 505G, and 505B arranged in the row direction (extension direction of the wiring GL). The wiring SLR, wiring SLG, and wiring SLB are electrically connected to the sub-pixels 505R, 505G, and 505B (not shown) arranged in the column direction (extension direction of the wiring SLR, etc.), respectively.

[0397] 21B shows an example of a circuit diagram of a pixel 505 that can be applied to the subpixels 505R, 505G, and 505B. The pixel 505 includes a transistor M1, a transistor M2, a transistor M3, a capacitor C1, and a light-emitting device EL. A wiring GL and a wiring SL are electrically connected to the pixel 505. The wiring SL corresponds to any one of the wirings SLR, SLG, and SLB shown in FIG. 21A.

[0398] The transistor M1 has a gate electrically connected to a wiring GL, one of a source and a drain electrically connected to a wiring SL, and the other electrically connected to one electrode of a capacitor C1 and the gate of the transistor M2. The transistor M2 has one of a source and a drain electrically connected to a wiring AL, and the other of a source and a drain electrically connected to one electrode of a light-emitting device EL, the other electrode of the capacitor C1, and one of a source and a drain of the transistor M3. The transistor M3 has a gate electrically connected to a wiring GL, and the other of a source and a drain electrically connected to a wiring RL. The light-emitting device EL has the other electrode electrically connected to a wiring CL.

[0399] The wiring SL is supplied with a data potential D. The wiring GL is supplied with a selection signal. The selection signal includes a potential that turns on a transistor and a potential that turns off a transistor.

[0400] A reset potential is applied to the wiring RL. An anode potential is applied to the wiring AL. A cathode potential is applied to the wiring CL. In the pixel 505, the anode potential is higher than the cathode potential. The reset potential applied to the wiring RL can be a potential such that the potential difference between the reset potential and the cathode potential is smaller than the threshold voltage of the light-emitting device EL. The reset potential can be a potential higher than the cathode potential, the same as the cathode potential, or a potential lower than the cathode potential.

[0401] The transistors M1 and M3 function as switches. The transistor M2 functions as a transistor for controlling the current flowing through the light-emitting device EL. For example, it can be said that the transistor M1 functions as a selection transistor and the transistor M2 functions as a drive transistor.

[0402] Here, it is preferable that all of the transistors M1 to M3 be LTPS transistors. Alternatively, it is preferable that the transistors M1 and M3 be OS transistors and the transistor M2 be an LTPS transistor.

[0403] Alternatively, OS transistors may be used for all of the transistors M1 to M3. In this case, an LTPS transistor may be used for one or more of the transistors included in the driver circuit portion 502 and the driver circuit portion 503, and OS transistors may be used for the remaining transistors. For example, an OS transistor may be used for the transistor provided in the display portion 504, and an LTPS transistor may be used for the transistors provided in the driver circuit portion 502 and the driver circuit portion 503.

[0404] As the OS transistor, a transistor including an oxide semiconductor for a semiconductor layer in which a channel is formed can be used. The semiconductor layer preferably contains, for example, indium, M (M is one or more selected from gallium, aluminum, silicon, boron, yttrium, tin, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium), and zinc. In particular, M is preferably one or more selected from aluminum, gallium, yttrium, and tin. In particular, an oxide containing indium, gallium, and zinc (also referred to as IGZO) is preferably used for the semiconductor layer of the OS transistor. Alternatively, an oxide containing indium, tin, and zinc is preferably used. Alternatively, an oxide containing indium, gallium, tin, and zinc is preferably used.

[0405] A transistor using an oxide semiconductor, which has a wider band gap and a lower carrier density than silicon, can achieve an extremely small off-state current. Therefore, the small off-state current allows charge stored in a capacitor connected in series with the transistor to be held for a long period of time. Therefore, it is preferable to use transistors including oxide semiconductors for the transistors M1 and M3 connected in series with the capacitor C1. Using transistors including oxide semiconductors as the transistors M1 and M3 can prevent charge stored in the capacitor C1 from leaking through the transistor M1 or M3. Furthermore, because charge stored in the capacitor C1 can be held for a long period of time, a still image can be displayed for a long period of time without rewriting data in the pixel 505.

[0406] Note that although the transistors are shown as n-channel transistors in FIG. 21B, p-channel transistors can also be used.

[0407] In addition, the transistors included in the pixel 505 are preferably formed side by side on the same substrate.

[0408] As the transistor included in the pixel 505, a transistor having a pair of gates overlapping with each other with a semiconductor layer interposed therebetween can be used.

[0409] In a transistor having a pair of gates, when the pair of gates are electrically connected to each other and supplied with the same potential, the on-state current of the transistor is increased and the saturation characteristics are improved. A potential for controlling the threshold voltage of the transistor may be supplied to one of the pair of gates. Supplying a constant potential to one of the pair of gates can improve the stability of the electrical characteristics of the transistor. For example, one gate of the transistor may be electrically connected to a wiring to which a constant potential is supplied, or to its own source or drain.

[0410] 21C is an example of a pixel 505 in which the transistors M1 and M3 each have a pair of gates. The pair of gates of the transistors M1 and M3 are electrically connected. With this configuration, the period for writing data to the pixel 505 can be shortened.

[0411] 21D is an example in which a transistor having a pair of gates is used for the transistor M2 in addition to the transistors M1 and M3. The pair of gates of the transistor M2 are electrically connected. By using such a transistor for the transistor M2, the saturation characteristics are improved, which makes it easier to control the emission luminance of the light-emitting device EL, thereby improving the display quality.

[0412] [Example of Transistor Structure] Hereinafter, an example of a cross-sectional structure of a transistor that can be applied to the display panel will be described.

[0413] Configuration Example 1 FIG. 22A is a cross-sectional view including a transistor 510. FIG.

[0414] The transistor 510 is provided on a substrate 501 and has polycrystalline silicon applied to a semiconductor layer. For example, the transistor 510 corresponds to the transistor M2 of the pixel 505. That is, Fig. 22A shows an example in which one of the source and the drain of the transistor 510 is electrically connected to the conductive layer 531 of the light-emitting device.

[0415] The transistor 510 includes a semiconductor layer 511, an insulating layer 512, a conductive layer 513, and the like. The semiconductor layer 511 includes a channel formation region 511i and a low-resistance region 511n. The semiconductor layer 511 includes silicon. The semiconductor layer 511 preferably includes polycrystalline silicon. A part of the insulating layer 512 functions as a gate insulating layer. A part of the conductive layer 513 functions as a gate electrode.

[0416] Note that the semiconductor layer 511 can also include a metal oxide (also referred to as an oxide semiconductor) that exhibits semiconductor characteristics. In this case, the transistor 510 can be called an OS transistor.

[0417] The low-resistance region 511n is a region containing an impurity element. For example, when the transistor 510 is an n-channel transistor, phosphorus, arsenic, or the like may be added to the low-resistance region 511n. On the other hand, when the transistor 510 is a p-channel transistor, boron, aluminum, or the like may be added to the low-resistance region 511n. Furthermore, in order to control the threshold voltage of the transistor 510, the above-mentioned impurities may be added to the channel formation region 511i.

[0418] An insulating layer 521 is provided over a substrate 501. A semiconductor layer 511 is provided over the insulating layer 521. An insulating layer 512 is provided to cover the semiconductor layer 511 and the insulating layer 521. A conductive layer 513 is provided over the insulating layer 512 so as to overlap with the semiconductor layer 511.

[0419] An insulating layer 522 is provided to cover the conductive layer 513 and the insulating layer 512. A conductive layer 514a and a conductive layer 514b are provided over the insulating layer 522. The conductive layer 514a and the conductive layer 514b are electrically connected to the low-resistance region 511n through openings provided in the insulating layer 522 and the insulating layer 512. A part of the conductive layer 514a functions as one of the source electrode and the drain electrode, and a part of the conductive layer 514b functions as the other of the source electrode and the drain electrode. An insulating layer 523 is provided to cover the conductive layer 514a, the conductive layer 514b, and the insulating layer 522.

[0420] A conductive layer 531 functioning as a pixel electrode is provided over the insulating layer 523. The conductive layer 531 is provided over the insulating layer 523 and is electrically connected to the conductive layer 514b in an opening provided in the insulating layer 523. Although not shown here, an EL layer and a common electrode can be stacked over the conductive layer 531.

[0421] 22B shows a transistor 510a having a pair of gate electrodes, which is different from the transistor 510a shown in FIG. 22A in that a conductive layer 515 and an insulating layer 516 are included.

[0422] The conductive layer 515 is provided over the insulating layer 521. An insulating layer 516 is provided to cover the conductive layer 515 and the insulating layer 521. The semiconductor layer 511 is provided so that at least a channel formation region 511i overlaps with the conductive layer 515 with the insulating layer 516 interposed therebetween.

[0423] 22B , part of the conductive layer 513 functions as a first gate electrode, part of the conductive layer 515 functions as a second gate electrode, part of the insulating layer 512 functions as a first gate insulating layer, and part of the insulating layer 516 functions as a second gate insulating layer.

[0424] Here, when the first gate electrode and the second gate electrode are electrically connected, the conductive layer 513 and the conductive layer 515 may be electrically connected through openings provided in the insulating layers 512 and 516 in a region not shown. When the second gate electrode and the source or drain are electrically connected, the conductive layer 514a or the conductive layer 514b may be electrically connected to the conductive layer 515 through openings provided in the insulating layers 522, 512, and 516 in a region not shown.

[0425] 22A or 22B can be used as an example of a transistor 510. In this case, the transistor 510a may be used as all the transistors constituting the pixel 505, the transistor 510 may be used as all the transistors constituting the pixel 505, or the transistor 510 may be used as all the transistors constituting the pixel 505, or the transistor 510a and the transistor 510 may be used in combination.

[0426] [Structure Example 3] Hereinafter, a structure example including both a transistor in which silicon is used for a semiconductor layer and a transistor in which a metal oxide is used for a semiconductor layer will be described.

[0427] FIG. 22C shows a cross-sectional schematic diagram including transistor 510a and transistor 550.

[0428] For the transistor 510a, refer to the above-described Structure Example 1. Note that although the example using the transistor 510a is shown here, a structure including the transistor 510 and the transistor 550 may be used, or a structure including all of the transistor 510, the transistor 510a, and the transistor 550 may be used.

[0429] The transistor 550 is a transistor in which a metal oxide is used for a semiconductor layer. The configuration shown in Figure 22C is an example in which the transistor 550 corresponds to the transistor M1 of the pixel 505, and the transistor 510a corresponds to the transistor M2. That is, Figure 22C is an example in which one of the source and the drain of the transistor 510a is electrically connected to the conductive layer 531.

[0430] FIG. 22C shows an example in which the transistor 550 has a pair of gates.

[0431] The transistor 550 includes a conductive layer 555, an insulating layer 522, a semiconductor layer 551, an insulating layer 552, a conductive layer 553, and the like. Part of the conductive layer 553 functions as a first gate of the transistor 550, and part of the conductive layer 555 functions as a second gate of the transistor 550. In this case, part of the insulating layer 552 functions as a first gate insulating layer of the transistor 550, and part of the insulating layer 522 functions as a second gate insulating layer of the transistor 550.

[0432] The conductive layer 555 is provided over the insulating layer 512. The insulating layer 522 is provided to cover the conductive layer 555. The semiconductor layer 551 is provided over the insulating layer 522. The insulating layer 552 is provided to cover the semiconductor layer 551 and the insulating layer 522. The conductive layer 553 is provided over the insulating layer 552 and has a region overlapping with the semiconductor layer 551 and the conductive layer 555.

[0433] An insulating layer 526 is provided to cover the insulating layer 552 and the conductive layer 553. A conductive layer 554a and a conductive layer 554b are provided over the insulating layer 526. The conductive layer 554a and the conductive layer 554b are electrically connected to the semiconductor layer 551 through openings provided in the insulating layer 526 and the insulating layer 552. A part of the conductive layer 554a functions as one of the source electrode and the drain electrode, and a part of the conductive layer 554b functions as the other of the source electrode and the drain electrode. An insulating layer 523 is provided to cover the conductive layer 554a, the conductive layer 554b, and the insulating layer 526.

[0434] Here, the conductive layers 514a and 514b electrically connected to the transistor 510a are preferably formed by processing the same conductive film as the conductive layers 554a and 554b. Figure 22C shows a configuration in which the conductive layers 514a, 514b, 554a, and 554b are formed on the same surface (i.e., in contact with the top surface of the insulating layer 526) and contain the same metal element. In this case, the conductive layers 514a and 514b are electrically connected to the low-resistance region 511n through openings provided in the insulating layer 526, the insulating layer 552, the insulating layer 522, and the insulating layer 512. This is preferable because it simplifies the manufacturing process.

[0435] The conductive layer 513 functioning as the first gate electrode of the transistor 510a and the conductive layer 555 functioning as the second gate electrode of the transistor 550 are preferably formed by processing the same conductive film. In Figure 22C, the conductive layer 513 and the conductive layer 555 are formed on the same surface (i.e., in contact with the top surface of the insulating layer 512) and contain the same metal element. This is preferable because it simplifies the manufacturing process.

[0436] In FIG. 22C , the insulating layer 552 functioning as the first gate insulating layer of the transistor 550 covers the end portion of the semiconductor layer 551. However, as in the transistor 550 a shown in FIG. 22D , the insulating layer 552 may be processed so that the top surface shape thereof matches or substantially matches the top surface shape of the conductive layer 553.

[0437] In this specification, the phrase "top surface shapes generally match" refers to the overlap of at least a portion of the contours between stacked layers. For example, this includes cases where the upper and lower layers are processed using the same mask pattern or a portion of the same mask pattern. However, strictly speaking, the contours may not overlap, and the upper layer may be located inside the lower layer, or outside the lower layer. In these cases, the phrase "top surface shapes generally match" also applies.

[0438] Although the transistor 510a corresponds to the transistor M2 and is electrically connected to the pixel electrode in this example, the present invention is not limited to this. For example, the transistor 550 or the transistor 550a may correspond to the transistor M2. In this case, the transistor 510a corresponds to the transistor M1, the transistor M3, or another transistor.

[0439] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0440] Embodiment 8 In this embodiment, electronic devices of one embodiment of the present invention will be described with reference to FIGS. 23 and 24. FIG.

[0441] The image processing system of this embodiment can be applied to various electronic devices that have a function of displaying images, and therefore can significantly reduce the power consumption of electronic devices that have a display unit.

[0442] Examples of electronic devices include electronic devices with relatively large screens such as television sets, desktop or notebook personal computers, computer monitors, digital signage, large game machines such as pachinko machines, as well as digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, personal digital assistants, and sound playback devices.

[0443] In particular, the display panel of one embodiment of the present invention can have high resolution and can therefore be suitably used in electronic devices having a relatively small display area, such as wristwatch-type and bracelet-type information terminals (wearable devices).

[0444] The display panel of one embodiment of the present invention preferably has extremely high resolution, such as HD (1280 × 720 pixels), FHD (1920 × 1080 pixels), WQHD (2560 × 1440 pixels), WQXGA (2560 × 1600 pixels), 4K (3840 × 2160 pixels), or 8K (7680 × 4320 pixels). A resolution of 4K, 8K, or higher is particularly preferable. Furthermore, the pixel density (resolution) of the display panel of one embodiment of the present invention is preferably 50 ppi or higher, more preferably 100 ppi or higher, more preferably 300 ppi or higher, more preferably 500 ppi or higher, more preferably 1000 ppi or higher, more preferably 2000 ppi or higher, more preferably 3000 ppi or higher, more preferably 5000 ppi or higher, and even more preferably 7000 ppi or higher. By using a display panel having either or both of high resolution and high definition, it is possible to further enhance the sense of realism and depth. Furthermore, there is no particular limitation on the screen ratio (aspect ratio) of the display panel of one embodiment of the present invention. For example, the display panel can support various screen ratios such as 1:1 (square), 4:3, 16:9, and 16:10.

[0445] The electronic device of this embodiment may have a sensor (including the function of detecting, detecting, or measuring force, displacement, position, velocity, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays).

[0446] The electronic device of the present embodiment can have various functions, such as a function to display various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function to display a calendar, date, time, etc., a function to execute various software (programs), a wireless communication function, a function to read out programs or data recorded on a recording medium, etc.

[0447] The electronic device 6500 shown in FIG. 23A is a portable information terminal that can be used as a smartphone.

[0448] The electronic device 6500 includes a housing 6501, a display portion 6502, a power button 6503, a button 6504, a speaker 6505, a microphone 6506, a camera 6507, a light source 6508, and the like. The display portion 6502 has a touch panel function.

[0449] The display panel of one embodiment of the present invention can be applied to the display portion 6502 .

[0450] FIG. 23B is a schematic cross-sectional view including the end of the housing 6501 on the microphone 6506 side.

[0451] A light-transmitting protective member 6510 is provided on the display surface side of the housing 6501, and a display panel 6511, optical members 6512, a touch sensor panel 6513, a printed circuit board 6517, a battery 6518, etc. are arranged in the space surrounded by the housing 6501 and the protective member 6510.

[0452] A display panel 6511, an optical member 6512, and a touch sensor panel 6513 are fixed to the protective member 6510 by adhesive layers (not shown).

[0453] In a region outside the display portion 6502, a part of the display panel 6511 is folded back, and an FPC 6515 is connected to the folded back part. An IC 6516 is mounted on the FPC 6515. The FPC 6515 is connected to a terminal provided on a printed circuit board 6517.

[0454] The flexible display of one embodiment of the present invention can be applied to the display panel 6511. Therefore, an extremely lightweight electronic device can be realized. In addition, since the display panel 6511 is extremely thin, a large-capacity battery 6518 can be mounted thereon while keeping the thickness of the electronic device small. Furthermore, by folding back a part of the display panel 6511 and arranging a connection portion with the FPC 6515 on the back side of the pixel portion, an electronic device with a narrow frame can be realized.

[0455] 23C shows an example of a television set. A television set 7100 has a display portion 7000 built into a housing 7101. Here, the housing 7101 is supported by a stand 7103.

[0456] 23C can be operated using operation switches provided on the housing 7101 and a separate remote control 7111. Alternatively, the display portion 7000 may be provided with a touch sensor, and the television set 7100 may be operated by touching the display portion 7000 with a finger or the like. The remote control 7111 may have a display portion that displays information output from the remote control 7111. Using operation keys or a touch panel provided on the remote control 7111, the channel and volume can be controlled, and an image displayed on the display portion 7000 can be controlled.

[0457] The television device 7100 is configured to include a receiver, a modem, and the like. Ordinary television broadcasts can be received using the receiver. Furthermore, by connecting to a wired or wireless communication network via the modem, it is possible to perform one-way (from a sender to a receiver) or two-way (between a sender and a receiver, or between receivers, etc.) information communication.

[0458] 23D shows an example of a laptop personal computer 7200. The laptop personal computer 7200 includes a housing 7211, a keyboard 7212, a pointing device 7213, and an external connection port 7214. The housing 7211 includes a display portion 7000.

[0459] 23E and 23F show an example of digital signage.

[0460] 23E includes a housing 7301, a display portion 7000, a speaker 7303, and the like. The digital signage 7300 may further include an LED lamp, operation keys (including a power switch or an operation switch), a connection terminal, various sensors, a microphone, and the like.

[0461] 23F shows a digital signage 7400 attached to a cylindrical pillar 7401. The digital signage 7400 has a display unit 7000 provided along the curved surface of the pillar 7401.

[0462] The larger the display unit 7000, the more information can be provided at one time. Also, the larger the display unit 7000, the more easily it will attract people's attention, which can increase the advertising effectiveness of, for example, advertisements.

[0463] Applying a touch panel to the display unit 7000 is preferable because it not only displays images or videos on the display unit 7000 but also allows the user to intuitively operate it. Furthermore, when used to provide information such as route information or traffic information, the intuitive operation can improve usability.

[0464] 23E and 23F , the digital signage 7300 or the digital signage 7400 is preferably capable of wirelessly linking with an information terminal 7311 or an information terminal 7411 such as a smartphone carried by a user. For example, advertising information displayed on the display unit 7000 can be displayed on the screen of the information terminal 7311 or the information terminal 7411. By operating the information terminal 7311 or the information terminal 7411, the display on the display unit 7000 can be switched.

[0465] Furthermore, the digital signage 7300 or the digital signage 7400 can be made to run a game using the screen of the information terminal 7311 or the information terminal 7411 as an operation means (controller), thereby allowing an unspecified number of users to simultaneously participate in and enjoy the game.

[0466] 23C to 23F, a display panel of one embodiment of the present invention can be applied to the display portion 7000.

[0467] The electronic device shown in Figures 24A to 24G has a housing 9000, a display unit 9001, a speaker 9003, operation keys 9005 (including a power switch or an operation switch), a connection terminal 9006, a sensor 9007 (including a function to sense, detect, or measure force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays), a microphone 9008, etc.

[0468] The electronic devices shown in Figures 24A to 24G have various functions. For example, they may have a function to display various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function to display a calendar, date, or time, a function to control processing using various software (programs), a wireless communication function, a function to read and process programs or data recorded on a recording medium, etc. Note that the functions of the electronic devices are not limited to these, and they may have various other functions. The electronic devices may have multiple display units. Furthermore, the electronic devices may have a function to include a camera or the like to capture still images or videos and store them on a recording medium (external or built-in to the camera), a function to display the captured images on the display unit, etc.

[0469] Details of the electronic device shown in Figures 24A to 24G will be described below.

[0470] FIG. 24A is a perspective view showing a mobile information terminal 9101. The mobile information terminal 9101 can be used as, for example, a smartphone. Note that the mobile information terminal 9101 may be provided with a speaker 9003, a connection terminal 9006, a sensor 9007, and the like. The mobile information terminal 9101 can display text and image information on multiple surfaces. FIG. 24A shows an example in which three icons 9050 are displayed. Information 9051, indicated by a dashed rectangle, can also be displayed on another surface of the display unit 9001. Examples of the information 9051 include notifications of incoming emails, SNS messages, phone calls, etc., the title of the email or SNS message, the sender's name, the date and time, the remaining battery level, and radio wave intensity. Alternatively, an icon 9050 or the like may be displayed in the position where the information 9051 is displayed.

[0471] 24B is a perspective view showing the mobile information terminal 9102. The mobile information terminal 9102 has a function of displaying information on three or more surfaces of the display unit 9001. Here, an example is shown in which information 9052, information 9053, and information 9054 are displayed on different surfaces. For example, a user can check information 9053 displayed in a position that can be observed from above the mobile information terminal 9102 while the mobile information terminal 9102 is placed in a breast pocket of clothes. The user can check the display without taking the mobile information terminal 9102 out of the pocket and decide, for example, whether to answer a call.

[0472] 24C is a perspective view showing a tablet terminal 9103. The tablet terminal 9103 is capable of executing various applications such as mobile phone calls, e-mail, text browsing and creation, music playback, internet communication, and computer games, for example. The tablet terminal 9103 has a display unit 9001, a camera 9002, a microphone 9008, and a speaker 9003 on the front side of a housing 9000, operation keys 9005 as operation buttons on the left side of the housing 9000, and a connection terminal 9006 on the bottom.

[0473] FIG. 24D is a perspective view showing a wristwatch-type mobile information terminal 9200. The mobile information terminal 9200 can be used as, for example, a smart watch (registered trademark). The display surface of the display unit 9001 is curved, and display can be performed along the curved display surface. The mobile information terminal 9200 can also perform hands-free calling by communicating with, for example, a headset capable of wireless communication. The mobile information terminal 9200 can also perform data transmission and charging with another information terminal through a connection terminal 9006. Note that charging may be performed by wireless power supply.

[0474] 24E to 24G are perspective views showing a foldable mobile information terminal 9201. Also, FIG. 24E is a perspective view of the mobile information terminal 9201 in an unfolded state, FIG. 24G is a perspective view of the mobile information terminal 9201 in a folded state, and FIG. 24F is a perspective view of a state in the process of changing from one of FIGS. 24E and 24G to the other. The mobile information terminal 9201 has excellent portability in a folded state, and excellent display visibility due to a seamless, wide display area in an unfolded state. The display portion 9001 of the mobile information terminal 9201 is supported by three housings 9000 connected by hinges 9055. For example, the display portion 9001 can be bent with a curvature radius of 0.1 mm or more and 150 mm or less.

[0475] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0476] 10A: Electronic device, 10: Electronic device, 11: Display unit, 12: Computing unit, 13: Image processing unit, 14: Communication unit, 15: Sensor unit, 16: Imaging unit, 17: Audio control unit, 20: Housing, 21: Display device, 22: Input device, 23: Drive unit, 24: Drive unit, 25: Area, 31: Illuminance sensor, 32: Camera, 33: Speaker, 34: Microphone, 35: Camera, 36: Acceleration sensor, 40: User, 41: Image, 42: Image, 50: Contact position, 51: Area, 52: Area, 53: Area, 55: Area, 61: Main body, 62: Keyboard, 63: Mouse, 70: Display unit, 71: Cursor, 72: Window, 73: Window, 74: Background, 80: Server, 81: Computing unit, 82: Image processing unit, 83: Communication unit

Claims

1. The device has a display unit, an input unit, a calculation unit, and an image processing unit, the input unit has a function of acquiring position information of an instruction operation by a user, the calculation unit has a function of determining a first region and a second region based on the position information, the image processing unit has a function of generating a second image by performing image processing on a portion of a first image corresponding to the first region, the display unit has a function of displaying the second image, An area where the user performs a swipe operation is defined as the first area, and other areas are defined as the second area; performing image processing on the first region to reduce one or both of a resolution and a frame frequency; The image processing is not performed on the second region. Image processing system.

2. A display device having a display unit, an input unit, a calculation unit, and an image processing unit, the input unit has a function of acquiring position information of an instruction operation by a user, the calculation unit has a function of determining a first region and a second region based on the position information, the image processing unit has a function of generating a second image by performing image processing on a portion of a first image corresponding to the first region, the display unit has a function of displaying the second image, An area where the user performs a swipe operation is defined as the first area, and other areas are defined as the second area; performing image processing on the first region to reduce one or both of a resolution and a frame frequency; The image processing is not performed on the second region, an area where the user performs a tap operation is defined as the first area, and an area on the display unit that is farthest from the first area is defined as the second area; displaying the first region at the highest resolution and frame frequency; displaying the second region at the lowest resolution and frame frequency; a region between the first region and the second region is displayed at a resolution and a frame frequency equal to or lower than those of the first region and equal to or higher than those of the second region; Image processing system.

3. A display device having a display unit, an input unit, a calculation unit, and an image processing unit, the input unit has a function of acquiring position information of an instruction operation by a user, the calculation unit has a function of determining a first region and a second region based on the position information, the image processing unit has a function of generating a second image by performing image processing on a portion of a first image corresponding to the first region, the display unit has a function of displaying the second image, An area where the user performs a swipe operation is defined as the first area, and other areas are defined as the second area; performing image processing on the first region to reduce one or both of a resolution and a frame frequency; The image processing is not performed on the second region, an area where the user performs a tap operation is defined as the first area, and an area on the display unit that is farthest from the first area is defined as the second area; displaying the first region at the highest resolution and frame frequency; displaying the second region at the lowest resolution and frame frequency; a region between the first region and the second region is displayed at a resolution and a frame frequency equal to or lower than those of the first region and equal to or higher than those of the second region; The area hidden by the user's fingers and hands is driven to be turned off. Image processing system.