Electronic apparatus

Abstract

To provide a display device including a photosensor having a pixel configuration which prevents decrease in imaging quality caused by change in output of the photosensor.SOLUTION: A display device has a pixel layout structure in which a shielding line is disposed between an FD and an imaging signal line (a PR line, a TX line, or an SE line) or between the FD and a display signal line in order to reduce parasitic capacitance or eliminate the parasitic capacitance between the FD and the signal line for suppressing change in potential of the FD. As the shielding line, a common potential line with a fixed potential such as an imaging power supply line, a display power supply line, a GND line, and a common potential line is used.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an electronic device having a circuit configured with a photosensor and a transistor. Electronic devices that incorporate electro-optical devices, such as liquid crystal display panels, as components. Regarding equipment. [Background technology]

[0002] CMOS sensors are primarily used in digital cameras and mobile phones, and play an important role in image capture. A CMOS sensor is a photosensor that uses the amplification function of a MOS transistor. It can be manufactured using a general-purpose CMOS process. In addition, the driving voltage is lower than that of a CCD sensor. Since the power consumption of the solid-state imaging device is low, the power consumption can be kept low.

[0003] Also, display devices equipped with touch sensors are attracting attention. The device is called a touch panel or a touch screen (hereinafter, simply referred to as a "touch panel"). Touch panels are used mainly in personal computers and mobile phones. It is equipped with a function that allows display and operation on the same panel. A display device equipped with a touch sensor of this type is disclosed in Patent Document 1.

[0004] The CMOS sensor stores charge using a photodiode and reads out the charge. and resetting the charge generated by the photodiode during the above three operations. The node (hereafter referred to as FD) that accumulates charge due to the photocurrent generated and the wiring that supplies the control signal. The potential of the FD that stores this charge is less susceptible to fluctuations in the potential of the signal line. The configuration of a solid-state imaging device having this layout is disclosed in Patent Document 2. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-292276 [Patent Document 2] Japanese Patent Application Laid-Open No. 2006-148513 Summary of the Invention [Problem to be solved by the invention]

[0006] During the above three operations, the FD and the control If there is parasitic capacitance between the wiring that supplies the control signal and other signal lines, The change in the voltage of the FD changes, which in turn changes the output of the photosensor, resulting in poor image quality. decreases.

[0007] In addition, in a display device using a CMOS sensor, an FD is placed in each pixel. Therefore, just like the wiring of the image sensor, if there is parasitic capacitance between the signal line of the display element and the FD, When the signal changes, the potential of the FD changes. As a result, the output of the photosensor changes. This causes the image quality to deteriorate.

[0008] The goal was to create a pixel configuration that would prevent changes in photosensor output and a decline in imaging quality. It shall be one of the following. [Means for solving the problem]

[0009] To suppress the change in the potential of the FD, the parasitic capacitance between the FD and the signal line is reduced, or To eliminate capacitance, the FD and imaging signal lines (PR wiring, TX wiring, SE wiring) The pixel layout is configured so that shield wiring is placed between the FD and the display signal line, or between the FD and the display signal line. The shield wiring can be used for the imaging power line, the display power line, the GND wiring, or the common voltage line. A common wiring with a fixed potential such as a potential wiring is used.

[0010] One embodiment of the present invention disclosed in this specification is a method for connecting two capacitance lines of adjacent pixels to a first shield wiring. and the second shield wiring, and are connected between the FD (node) and the display signal line, respectively. By placing the first pixel electrode and the first signal a first transistor electrically connected to the line and a second transistor electrically connected to the photodiode; a second transistor; and a third transistor electrically connected to the second pixel electrode and the second signal line. a first transistor electrically connected to a node that stores charge; The node has a first seal between the first transistor and a first signal line electrically connected thereto. the node is connected to a second signal line electrically connected to the third transistor; The electronic device is characterized in that it has a pixel configuration having a second shield wiring in However, the node is shielded between the first transistor and the signal line electrically connected thereto. The term "having wiring" means that a shield wiring is arranged between the node and the signal line in the pixel plan view. This refers to a pixel layout.

[0011] The above configuration solves at least one of the above problems.

[0012] In addition, another aspect of the present invention is to use a capacitance line of a pixel as a shield line, and and the display signal line, and the same shield is placed between the FD (node) and TX wiring. The potential change of the FD is suppressed by arranging the wiring. Specifically, the pixel electrode and the first signal a first transistor electrically connected to the line and a second transistor electrically connected to the photodiode; The second transistor is electrically connected to a node that stores charge. The node is connected to a first signal line electrically connected to the first transistor through a shield wiring. a second signal line electrically connected to the gate of the second transistor; One of the features of the electronic device is that it has a shield wiring between the

[0013] The above configuration solves at least one of the above problems.

[0014] In addition, another aspect of the present invention is to use a capacitance line of a pixel as a shield line, and and the display signal line, and the same shield is placed between the FD (node) and PR wiring. The potential change of the FD is suppressed by arranging the wiring. Specifically, the pixel electrode and the first signal a first transistor electrically connected to the line and a second transistor electrically connected to the photodiode; The second transistor is electrically connected to a node that stores charge. The node is connected to a first signal line electrically connected to the first transistor through a shield wiring. a node between the photodiode and a second signal line electrically connected thereto; One of the features of this electronic device is that it has shield wiring.

[0015] The above configuration solves at least one of the above problems.

[0016] In addition, another aspect of the present invention is to use a capacitance line of a pixel as a shield line, and and the display signal line, and the same shield is placed between the FD (node) and SE wiring. The potential change of the FD is suppressed by arranging the wiring. Specifically, the pixel electrode and the first signal a first transistor electrically connected to the line and a second transistor electrically connected to the photodiode; a second transistor, a third transistor whose gate is the node for storing charge, and a third transistor a fourth transistor electrically connected to the third transistor, The node is electrically connected to the first transistor. a shield wiring between the first signal line and the node; and a gate of a fourth transistor. The shield wiring is provided between the terminal and a second signal line electrically connected thereto. It is an electronic device that

[0017] The above configuration solves at least one of the above problems. [Effects of the Invention]

[0018] By reducing the parasitic capacitance with the signal line that may affect the node potential, This can suppress fluctuations in the sensor output and prevent degradation of imaging quality. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is an external view illustrating one embodiment of the present invention. [Figure 2] 1 is a block diagram illustrating an embodiment of the present invention. [Figure 3] FIG. 1 is an equivalent circuit diagram of a pixel illustrating one embodiment of the present invention. [Figure 4] FIG. 1 is a schematic diagram of a driver circuit of a photosensor, illustrating one embodiment of the present invention. [Figure 5] FIG. 1 is an equivalent circuit diagram of a pixel illustrating one embodiment of the present invention. [Figure 6] FIG. 10 is a timing chart illustrating one embodiment of the present invention. [Figure 7]FIG. 10 is a layout diagram of a pixel illustrating one embodiment of the present invention. [Figure 8] 1A and 1B are a top view and a cross-sectional view of a periphery of a transistor connected to a photosensor, illustrating one embodiment of the present invention. [Figure 9] 1A and 1B are diagrams and a block diagram illustrating electronic devices according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the following description, and various modifications in form and details are possible by those skilled in the art. Furthermore, the present invention should not be construed as being limited to the description of the following embodiments. It is not something that can be done.

[0021] (Embodiment 1) In this embodiment, an example of an electronic device 1030 having a display unit 1032 for displaying images is shown. 1(A) and 1(B).

[0022] The display portion 1032 of the electronic device 1030 has a touch input function using a photosensor. As shown in (A), a plurality of keyboard buttons 1031 are displayed in a display area 1033. The display unit 1032 refers to the entire display area, and includes the area 1033 of the display unit. The user touches the desired keyboard button to input information, and the input is displayed on the display unit 1032. The information is displayed.

[0023] An example of how the electronic device 1030 is used is shown. For example, The user can enter characters by touching the indicated keyboard buttons in sequence with their fingers or without touching them. The text displayed as a result is displayed in an area other than the area 1033 of the display unit. When the user removes his / her fingers from the keyboard on the screen, the period when the output signal of the photosensor is not detected is After a certain time has passed, the keyboard display in area 1033 of the display will automatically disappear, The input text is also displayed in the area 1033 of the display unit, and the input text is displayed on the entire screen. The user can confirm the input. If the user wants to input again, he / she places his / her finger on the display unit 1032. The display will be restored by touching the screen in sequence or by detecting the output signal of the photosensor without touching it. A keyboard button can be displayed in the area 1033 to allow for character input.

[0024] Also, the changeover is not automatic, but is performed by the user pressing the changeover switch 1034 as shown in FIG. As shown in B), it is also possible to display an image on the display unit 1032 without the keyboard display. Also, by pressing the keyboard display switch 1036, the keyboard is displayed and It is also possible to make it possible to input a key.

[0025] Also, a changeover switch 1034, a power switch 1035, and a keyboard display switch 1036 are displayed as switch buttons on the display unit 1032, and the displayed switches Each operation can be performed by touching the corresponding button.

[0026] The electronic device 1030 also has at least a battery and memory for storing data information. Memory (Flash Memory circuit, SRAM circuit, DRAM circuit, etc.), CPU (medium It is preferable to have a configuration that includes a CPU, memory, and logic circuit. By providing this, various software can be installed and the personal computer It can have some or all of the functionality of the device.

[0027] In addition, the electronic device 1030 may be equipped with a tilt sensor such as a gyroscope or a three-axis acceleration sensor. A tilt detection unit is provided, and functions, particularly functions used by the electronic device 1030, are selected in response to a signal from the tilt detection unit. The display and input functions on the display surface can be switched by the arithmetic circuit. Therefore, the type, size, and layout of input keys are predetermined, like built-in operation keys. Unlike the conventional method, it is possible to improve the convenience for the user.

[0028] Next, an example of a display panel that constitutes the display unit 1032 will be described with reference to FIG. The display panel 100 includes a pixel circuit 101, a display element control circuit, and a photosensor control circuit. The pixel circuit 101 includes a plurality of pixels 103, 104 arranged in a matrix in the row and column directions. 4, 113, 114, and a photosensor 106. In this embodiment, the pixel 103 and the pixel 104 each have one display element. One photosensor 106 is disposed between pixels 113 and 114 and between pixels 114 and 115. Specifically, the pixel layout structure is one where one photosensor is placed for every four pixels.

[0029] The pixels 103, 104, 113, and 114 each include a transistor, a storage capacitor, and a liquid crystal layer. The transistors are connected to pixel electrodes 105, 115, 125, and 135. The transistor injects or extracts charge from the storage capacitor. The storage capacitor has the function of controlling the discharge of the charge equivalent to the voltage applied to the liquid crystal layer. By applying a voltage to the liquid crystal layer, the polarization direction changes. By creating contrast (gradation) of light that passes through the liquid crystal layer, an image is displayed. The light passing through the LCD device is irradiated from outside using external light (sunlight or illumination light). The liquid crystal layer is not particularly limited, and may be made of a known liquid crystal material (typically, nematic For example, polymer dispersed liquid crystal (P DLC (Polymer Dispersed Liquid Crystal), high-quality Dispersed liquid crystal (PNLC) or polymer network liquid crystal (PNLC) Polymer Network Liquid Crystal) is used as the liquid crystal layer. Alternatively, white display (bright display) may be achieved by utilizing scattered light from the liquid crystal.

[0030] The display element control circuit is a circuit for controlling the pixels 103, 104, 113, and 114. The signal lines (also called "source signal lines") such as video data signal lines are connected to the transistors. A display element driving circuit inputs signals to the pixel electrodes 105, 115, 125, and 135 via a The transistors arranged in each pixel are connected to the line 107 via scanning lines (also called "gate signal lines"). The display device includes a display element driver circuit 108 that inputs a signal to the gate electrode of the transistor.

[0031] For example, the display element driver circuit 108 connected to the scan line detects whether the pixels arranged in a particular row are active. The display element driver circuit 10 connected to the signal line has a function of selecting the display element to be driven. 7 has a function of applying a desired potential to the display elements of the pixels in the selected row. In the display element to which a high potential is applied by the display element driving circuit 108 connected to the scanning line, The transistor is turned on, and the signal is supplied from the display element driver circuit 107 connected to the signal line. The charge is supplied.

[0032] The photosensor 106 is a device such as a photodiode that receives light and generates an electrical signal. The light-receiving element has a function and a transistor.

[0033] The photosensor control circuit is a circuit for controlling the photosensor 106. The photosensor readout line is connected to the signal lines such as the photosensor output signal line and the photosensor reference signal line. The image sensor includes a circuit 109 and a photosensor driver circuit 110 connected to the scan lines. The photosensor driving circuit 110 drives the photosensors of the pixels arranged in a specific row. 106, the reset operation and the selection operation, which will be described later, are performed. The photosensor readout circuit 109 connected to the row 104 reads the photosensors of the pixels in the selected row. The output signal of the sensor 106 is extracted.

[0034] In this embodiment, a circuit diagram of the pixel 103 and the photosensor 106 will be described with reference to FIG. explain.

[0035] The pixel 301 includes a transistor 330, a storage capacitor 331, and a liquid crystal element 332. The photosensor 302 includes a photodiode 351, a transistor 352, and a transistor 353 and a transistor 354.

[0036] The transistor 330 has a gate connected to the gate signal line 310 and a source or drain connected to the The other of the source and drain is connected to the video data signal line 311. and one electrode of the liquid crystal element 332. The other electrode of the storage capacitor 331 is electrically connected to the capacitance wiring 312 and is kept at a constant potential. The other electrode of the liquid crystal element 332 is kept at a constant potential. It is a device that includes a liquid crystal layer between a pair of electrodes.

[0037] When "H" is applied to the gate signal line 310, the transistor 330 receives the video data signal. The potential of the signal line 311 is applied to a storage capacitor 331 and a liquid crystal element 332. The liquid crystal element 332 changes the light transmittance according to the applied potential. do.

[0038] The photodiode 351 has one electrode connected to the photodiode reset signal line 341 (P The other electrode is connected to either the source or drain of the transistor 352. The other of the source and drain of the transistor 352 is electrically connected to the FD( node).

[0039] The transistor 352 controls the voltage of the FD (node) and maintains the voltage. The gate is connected to a photosensor charge transfer signal line 342 (also called a TX line). The signal line 342 serves to control the switching of the transistor 352 .

[0040] The transistor 354 has a gate that is an FD (node) and a source or drain that is an FD (node). The power supply wiring 344 is electrically connected to the source of the transistor 354. One of the drains is electrically connected to one of the source and drain of the transistor 353. There are.

[0041] The gate of the transistor 353 is electrically connected to the photosensor reference signal line 345 (SE wiring). The other of the source and drain of the transistor 353 is connected to a photosensor It is electrically connected to an output signal line 343 (also called an OUT line).

[0042] Next, an example of the configuration of the photosensor readout circuit 109 will be described with reference to FIG. 4. For example, the display unit is composed of pixels of 1024 rows and 768 columns, and the display element is The pixel has one photo sensor, and the pixel has one photo sensor for every two rows and two columns. The display elements are configured with 1024 rows and 768 columns, and the photosensors are configured with 512 rows and 384 columns. The photo sensor output signal lines are shown as an example in which two columns are used as one set and output to the outside of the display device. One output is obtained from two photosensors sandwiched between eight pixels arranged in two rows and four columns.

[0043] Figure 3 shows the circuit configuration of a pixel, with four pixels in two rows and two columns, and one photosensor. There is one display element per pixel and one photosensor per four pixels. In the circuit configuration of the sensor readout circuit 109, some of the photosensors are also shown for the sake of explanation. Note that the transistor shown in FIG. 3 includes a transistor having an oxide semiconductor in a channel formation region. can be used.

[0044] As shown in FIG. 4, the scanning line driver circuit of the photosensor simultaneously drives four rows of pixels (i.e., The selected row is shifted by one row of photosensors, which corresponds to two rows of pixels. Here, the photosensors in each row are driven by a scanning line driving circuit. The path is continuously selected during the period when the selected row is shifted twice. By using this method, it is easy to improve the frame frequency of the image captured by the photosensor. This is particularly advantageous in the case of a large display device. The output of the photosensors for two rows is superimposed on the signal line 3. By repeating this process 512 times, all photosensors can be driven.

[0045] As shown in FIG. 4, the photosensor readout circuit 109 has one selector for every 24 columns of pixels. The selector has two columns of output signal lines 343 of the photosensors in the display section. One set is selected from 12 sets, and the output is obtained. The entire selector circuit 109 has 32 selectors, and simultaneously acquires 32 outputs. By selecting all 12 pairs of pixels using the selector, a total of 12 pixels equivalent to one row of photosensors can be obtained. 384 outputs can be obtained. 12 sets of selections by the selector are made by the photosensor. By shifting the selected row every time the scanning line driver circuit shifts the row, the output of all photosensors is obtained. It is possible.

[0046] In this embodiment, as shown in FIG. 4, a photosensor readout circuit 1 connected to a signal line 09 takes the output of the photosensor, which is an analog signal, outside the display device and After amplifying the signal using the amplifier installed in the part, it is converted into a digital signal using an AD converter. Of course, an AD converter is mounted on the same board as the display device, and the output of the photosensor is converted into digital data. It is also possible to configure the display device so that the signal is converted into a digital signal and then output to the outside.

[0047] A method for driving the photosensor circuit of FIG. 3 will be described with reference to the timing chart of FIG. do.

[0048] For the sake of simplicity, in Figure 6, TX910, PR911, and SE912 are binary-changing signals. Hereafter, the TX910 will be referred to as "High-TX" for the high potential and "Low" for the low potential. -TX”, and PR911 has high potential as “High-PR” and low potential as “Low-PR”, The SE912 expresses the high potential as "High-SE" and the low potential as "Low-SE". However, since each potential is actually an analog signal, each potential is not limited to two values ​​depending on the situation. It can take various values.

[0049] First, at time 901, TX910 is set to "High-TX". Then, at time 902, PR911 When set to "High-PR", the potential of FD 913 is the same as PR911, "High-PR This is called the reset operation.

[0050] When PR 911 is set to "Low-PR" at time 903, the potential 913 of FD becomes "High- PR” is held, and the pin photodiode is reverse biased (accumulation operation starts). At this time, light is incident on the i-layer of the pin photodiode, causing a reverse current to flow. Therefore, the amount of charge stored in the FD changes depending on the amount of light.

[0051] At time 904, when TX910 is set to "Low-TX", the FD outputs a pin photodiode The transfer of charge to the FD stops, and the amount of charge stored in the FD is determined (end of storage operation).

[0052] When SE 912 is set to "High-SE" at time 905, the power supply Charge is supplied from the line to the OUT line (start of read operation).

[0053] When SE912 is set to "Low-SE" at time 906, the charge from the power supply wiring to the OUT wiring The supply is stopped and OUT914 is determined (read operation is completed). A captured image can be generated.

[0054] After this, the process returns to the operation at time 901 and repeats the same operation.

[0055] In this embodiment, the reset operation, accumulation operation, and readout operation of all the photosensors are performed. By executing this, local shadows caused by external light can be detected. By performing appropriate image processing, it is possible to know the position where a finger or pen has touched the display device. In advance, you can select the operation corresponding to the touched position, for example, the character input. By specifying the type, desired characters can be input.

[0056] In the display device according to the present embodiment, a photosensor detects local shadows caused by external light. Therefore, even if a finger or pen does not physically come into contact with the display device, it can be used in close proximity without contact. If a shadow is formed by the touch of a finger or pen on the display device, it can be detected. This also includes coming close to each other without contact.

[0057] With the above configuration, the display unit 1032 can have a touch input function.

[0058] (Embodiment 2) In this embodiment, a circuit arrangement that is partially different from that in FIG. 3 is shown in FIG. 5, and an example of a pixel layout is shown in FIG. Shown below.

[0059] The pixel circuit is composed of a display circuit 3501 and a sensor circuit 3502 .

[0060] The display circuit is composed of a transistor 3530, a liquid crystal element 3532, and a capacitor 3531. The gate of the transistor 3530 is connected to the signal line 3510, and the source or drain One of the electrodes is connected to a signal line 3511, and the other is connected to one electrode of a capacitor 3531 and a liquid crystal element. The other electrode of the capacitor 3531 is connected to the signal line 3512. The other electrode of the liquid crystal element 3532 corresponds to a common electrode.

[0061] The sensor circuit is composed of pin photodiode 3551, FET-T3552, and FET- It consists of AMP3554 and FET-S3553. The gate of FET-T3552 is TX It is connected to two wires 3542 and 3547, and either the source or the drain is pin The other is connected to the cathode of the photodiode 3551 and the other is connected to the gate of the FET-AMP3554. connected to the

[0062] The source of the FET-AMP3554 is connected to the power supply wiring 3544, and the drain is connected to the FET-S The gate of FET-S3553 is connected to the SE wiring 3545. The source is connected to the OUT wiring 3543. The node is connected to PR wiring 3541 and 3546. A transistor including an oxide semiconductor in a channel formation region can be used as the transistor.

[0063] FIG. 7 is a plan view of an example of a pixel layout corresponding to the circuit diagram of FIG.

[0064] The pixel layout includes four display circuit layouts 3610a, 3610b, and 3610c. , 3610d and the layout of the sensor circuit 3620 are configured as one. The outputs 3610a, 3610b, 3610c, and 3610d are select FETs 360 3. Cs line 3601, video data line 3602, selection line 3600, COM line 360 It consists of 4.

[0065] The sensor circuit layout 3620 also includes a pin photodiode 3630, a semiconductor layer FET-T having semiconductor layer 3637, FET-AMP having semiconductor layer 3638, FET-T with 36, FD3641, vertical TX wiring 3632, horizontal TX wiring 3640 , Vertical PR wiring 3631, Horizontal PR wiring 3639, SE wiring 3635, OUT wiring 363 3, VDD wiring 3634. The materials of the semiconductor layers 3636, 3637, and 3638 are Although not particularly limited, polycrystalline semiconductor films (such as polysilicon films), microcrystalline semiconductor films, and Scientific formula InMO3(ZnO) m An oxide semiconductor film represented by (m>0) can be used. Here, M is one or more metal elements selected from Ga, Al, Mn, and Co. For example, M may be Ga, Ga and Al, Ga and Mn, or Ga and Co. The oxide semiconductor film may contain SiO2.

[0066] The layers of the pixel layout are semiconductor layers 3636, 3637, and 3638, a gate wiring layer 365, 1, it is formed by an SD wiring layer 3652, a Si layer 3653, and an ITO electrode layer 3654. , vertical TX wiring 3632, vertical PR wiring 3631 are SD wiring layer 3652, horizontal TX wiring 3640 and horizontal PR wiring 3639 are formed using the gate wiring layer 3651. The horizontal and vertical wiring are in contact with each other, forming a mesh-like layout. do.

[0067] The pixel layout is as follows: FD3641, video data line 3602, and signal line of adjacent pixel. There is a Cs wire 3601 that functions as a shield wiring. The parasitic capacitance formed between the plurality of signal lines is reduced, or the capacitance is reduced in response to a voltage change on the signal lines. It blocks the accompanying changes in the surrounding potential and suppresses the potential changes in the FD.

[0068] One of the features of the pixel layout is that the FD3641 is Keep sufficient distance from the PR wiring, SE wiring, and OUT wiring arranged in the pixel and adjacent pixels. Therefore, the potential change of FD3641 is suppressed and It is possible to provide a display device having an imaging function with little noise in the output signal of the photo sensor. do.

[0069] FIG. 8(A) shows an enlarged view of a part of FIG. 7, and FIG. 8(B) shows an example of its cross-sectional structure.

[0070] In addition, in FIGS. 8(A) and 8(B), the same reference numerals are used for the parts common to FIG.

[0071] In FIG. 8B, a transistor electrically connected to a photodiode is provided on a substrate 500. The gate wiring layer 3651 and the horizontal PR wiring 3639 are formed using the same material and in the same process. Also, a gate wiring layer 3651 and a gate insulating layer 502 covering the horizontal PR wiring 3639 are formed. A semiconductor layer 3637 is formed on the gate insulating layer 502 at a position overlapping the gate wiring layer 3651. is formed.

[0072] In addition, an SD wiring 3652 is formed so as to partially overlap the semiconductor layer 3637. A first interlayer insulating layer 505 is formed to cover the pin photodiode 3630. The silicon layer 3653p contains p-type impurity elements, and the i-type amorphous silicon A photoelectric conversion layer 3653i and a silicon layer 3653n containing an n-type impurity element are stacked. Form a replacement layer.

[0073] In addition, a second interlayer insulating layer covering the pin photodiode 3630 and the first interlayer insulating layer 505 is formed. An edge layer 509 is formed, and an ITO electrode 36 made of a transparent conductive film is formed on the second interlayer insulating layer 509. The ITO electrode 3654 is the S layer of the transistor having the semiconductor layer 3637. The electrode functions as a connection electrode that connects the D wiring 3652 and the pin photodiode 3630. In the display area, the pixel electrodes are made of the same material and in the same process as the ITO electrodes 3654. is formed.

[0074] In FIG. 8B, the transistor electrically connected to the pin photodiode 3630 Although the transistor is an example of a bottom gate type transistor, it is not particularly limited and may be any other bottom gate type transistor. The gate structure or the top gate structure may be used.

[0075] (Embodiment 3) In this embodiment, the display unit (touch input unit) having the touch input function described in the above embodiment is An example of an electronic device equipped with a touch panel will be described.

[0076] FIG. 9A shows an information terminal, which includes a housing 9630, a display portion 9631, operation keys 9632, a solar panel, and the like. The solar cell 9633 and the charge / discharge control circuit 9634 may be included. The touch panel can be opened and closed freely, and the power from the solar cell can be used for the touch panel or the display. The information terminal shown in FIG. 9(A) is an information terminal that supplies various information ( Functions that display still images, videos, text images, etc., calendars, dates, or times, etc. A function to display information on the display unit, and a touch input device to operate or edit the information displayed on the display unit by touch input. It can have functions such as the ability to control processing by various software (programs), etc. In FIG. 9A, a battery 9635 is used as an example of the charge / discharge control circuit 9634. Regarding the configuration of an information terminal having a DC-DC converter (hereinafter abbreviated as converter 9636), This is shown.

[0077] The solar cell 9633 is attached to the front and back of the housing 9630. This is preferable because it can be configured to charge. The use of lithium ion batteries has the advantage of enabling miniaturization.

[0078] The configuration and operation of the charge / discharge control circuit 9634 shown in FIG. 9A are shown in FIG. 9B. A block diagram is shown and explained. In FIG. 9(B), a solar cell 9633, a battery 9635, Inverter 9636, converter 9637, switches SW1 to SW3, display unit 9631 The figure shows the battery 9635, converter 9636, converter 9637, Switches SW1 to SW3 correspond to the charge / discharge control circuit 9634.

[0079] First, an example of operation when power is generated by the solar cell 9633 using external light will be described. The power generated by the solar cell is converted to a voltage for charging the Battery 9635. The voltage is increased or decreased by the photovoltaic cell 9636. When power from the 633 is used, switch SW1 is turned on and the converter 9637 The voltage is increased or decreased to the voltage required for the display unit 9631. When not displaying with the 9635 battery, turn SW1 off and SW2 on. The charging may be performed in the above manner.

[0080] Although the solar cell 9633 is shown as an example of a charging means, it may be possible to charge the battery by other means. It may be configured to charge the Terry 9635. It may also be configured to charge the Terry 9635 in combination with other charging means. This may also be configured as follows.

[0081] Furthermore, the display unit (touch panel) having the touch input function described in the above embodiment is provided. It goes without saying that the electronic device is not particularly limited to the electronic device shown in FIG. 9, as long as it satisfies the requirements.

[0082] This embodiment mode can be implemented by being appropriately combined with the configurations described in other embodiments. is. [Explanation of symbols]

[0083] 100: Display panel 101: Pixel circuit 103: Pixel 104: Pixel 105: pixel electrode 106: Photo sensor 107: Display element drive circuit connected to signal line 108: Display element drive circuit connected to the scanning line 109: Photosensor readout circuit 110: Photosensor drive circuit 113: Pixel 114: Pixel 115: pixel electrode 125: pixel electrode 135: pixel electrode

Claims

[Claim 1] a first transistor electrically connected to the pixel electrode and the first signal line; a second transistor electrically connected to the photodiode; a third transistor having a gate that is the node for storing charge; a fourth transistor electrically connected to the third transistor; the second transistor is electrically connected to the node; the node has a shield wiring between the node and the first signal line electrically connected to the first transistor; The electronic device includes the node having the shield wiring between the node and a second signal line electrically connected to the gate of the fourth transistor.

Images