Display device and electronic device

Abstract

Display device, which includes the following: a plurality of pixels arranged in a pixel unit, each pixel comprising a light emission unit (21) and a driver transistor (22) comprising a first gate electrode (G1) and a second gate electrode (G2) and configured to drive the light emission unit in response to a video signal applied to the first gate electrode (G1), the driver transistor and the light emission unit being connected in series between a power supply line providing a power supply potential (Vcc) and a power source line (35) providing a cathode potential; and a control unit (90) designed to control the plurality of pixels in such a way that a voltage of the second gate electrode of the driver transistor is changed in order to adjust the luminance, wherein the second gate electrodes (G2) of each of the pixels in a row are connected to a common control line (36) which is coupled to the control unit and wherein the first and second gate electrodes are arranged on a side opposite a semiconductor layer of the driver transistor.

Description

Technical field

[0001] The present disclosure relates to a display device and an electronic device, and in particular to a flat display device in which pixels, each containing a light emission unit, are arranged in a matrix pattern, and to an electronic device comprising the display device. State of the art

[0002] One example of a flat (flat panel) display device is an organic EL display device, which uses an organic EL device as a light emission unit (light emission device) that utilizes the phenomenon of light emission when an electric field is applied to an organic thin film by using the electroluminescence (EL) of an organic material.

[0003] In the flat display device embodied by this organic EL display device, if the characteristics (threshold voltage, mobility, and the like) of a driver transistor that drives the light emission unit differ for each pixel, the value of the current flowing through the driver transistor varies between the pixels. Consequently, even if the same voltage is applied to the gate electrode of the driver transistor between the pixels, the light emission luminance of the light emission unit varies between the pixels, affecting the uniformity of a screen.

[0004] Therefore, each pixel of the flat display device embodied by the organic EL display device has a threshold voltage correction function to correct variations in properties, e.g., variations in a threshold voltage V. th, of the driver transistor that drives the light emission unit, in units of pixels (see, for example, patent literature 1). List of prior art patent literature

[0005] Patent literature 1: Japanese patent application, publication no. 2008-287141.

[0006] US 2011 / 0234925 A1 apparently comprises a display device comprising a display unit with a plurality of pixels, each comprising a light-emitting element, a driver transistor, and a correction transistor; a sampling line, a signal line, a power supply line, and a gate line connected to the pixels; a sampling line driver circuit that applies a selection pulse to the sampling line; and a signal line driver circuit that writes a video signal to a pixel selected by the sampling line driver circuit by applying a video signal voltage to the signal line. The driver transistor and the correction transistor are connected in series on a path between the power supply line and the light-emitting element in each of the pixels.The gate voltage for correction, which is to be applied to the gate of the correction transistor via the gate line, is individually set in each unit area of ​​the display unit.

[0007] Further state of the art can be found in the following publications: US 2016 / 0042694 A1, US 2015 / 0243218 A1 and US 2015 / 0187253 A1. Disclosure of the invention Technical problem

[0008] The correction function mentioned above, used to compensate for variations in the driver transistor's characteristics, performs corrections in pixel units. With such a state-of-the-art correction function, it is difficult, for example, to achieve a sufficient improvement for partial deterioration of the screen's uniformity.

[0009] An objective of the present disclosure is to provide a display device and an electronic device, including the display device, that are capable of improving a partial deterioration of uniformity that cannot be dealt with by the correction function performed in units of pixels. Solution to the problem

[0010] To achieve the above-mentioned objective, a display device according to the present invention, as defined in claim 1, is proposed. Furthermore, in order to achieve the above-mentioned objective, an electronic device according to the present invention, as defined in claim 12, is proposed.

[0011] In the display device or electronic device with the configuration mentioned above, the threshold voltage of the driver transistor can be corrected by controlling the gate voltage of the other gate electrode of the driver transistor. Accordingly, it is possible to achieve a partial correction of the driver transistor's threshold voltage on the display. Advantageous effects of the invention

[0012] According to the present disclosure, because a partial correction can be achieved in the screen for the threshold voltage of the driver transistor, it is possible to improve a partial deterioration of uniformity that cannot be dealt with by the correction function performed in units of pixels.

[0013] It should be noted that the effect described here is not necessarily limiting and could be any effect described in this disclosure. Furthermore, the effects described here are merely examples and are not limited; additional effects may be provided. Brief description of the drawings [ Fig. 1] Fig. Figure 1 is a system configuration diagram that schematically shows a specific configuration of an active matrix display device to which the technology of the present disclosure is applied. [ Fig. 2] Fig. Figure 2 is a circuit diagram showing a circuit example of a pixel in the active matrix display device to which the technology of the present disclosure is applied. [ Fig. 3] Fig. 3A is an explanatory diagram for the effect on odd / even pixel rows due to oblique ion implantation, and Fig. 3B is an explanatory diagram for a partial deterioration of uniformity in a screen, e.g., horizontal stripes, which occur due to the luminance difference between odd / even pixel rows. [ Fig. 4] Fig. 4A is an equivalent circuit diagram showing a transistor with a neuron-MOS structure, and Fig. 4B is a circuit diagram of a pixel that uses a transistor with a neuron-MOS structure as a driver transistor. [ Fig. 5] Fig. Figure 5 is a circuit diagram showing a circuit configuration of a main part of an organic EL display device according to Example 1. [ Fig. 6] Fig. Figure 6 is a circuit diagram showing a circuit configuration of a main part of an organic EL display device according to Example 2. [ Fig. 7] Fig. Figure 7 is a circuit diagram showing a circuit configuration of a main part of an organic EL display device according to Example 3. [ Fig. 8] Fig. Figure 8 is a circuit diagram showing a circuit configuration of a main part of an organic EL display device according to Example 4. [ Fig. 9] Fig. Figure 9 is a circuit diagram showing a circuit example of a pixel in an active matrix display device to which an example 5 is applied. [ Fig. 10] Fig. Figure 10 is a cross-sectional view showing an example of a cross-sectional structure of a dual-gate TFT. [ Fig. 11] Fig. Figure 11 is a circuit diagram showing a circuit configuration of a main part of an organic EL display device according to Example 5. [ Fig. 12] Fig. 12 is an external view of a digital single-lens reflex camera with interchangeable lenses, Fig. 12A shows a front view of it and Fig. Figure 12B shows a rear view of it. [ Fig. 13] Fig. Figure 13 is an external view of a head-mounted display. Implementation(s) of the invention

[0014] The following are detailed descriptions of embodiments for carrying out the technology of this disclosure (hereinafter referred to as "embodiments") with reference to the drawings. The technology of this disclosure is not limited to these embodiments, and the various numerical values, materials, and the like in the embodiments are merely examples. In the following description, the same components or components with the same function are designated by the same reference symbols, and any duplicate description is omitted. It should be noted that the descriptions will be given in the following order. 1. Display device and electronic device according to the present disclosure, General description 2. Display device to which the technology of the present disclosure is applied 2-1. System configuration 2-2. Pixel circuit 2-3. Basic circuit operation 2-4. Partial deterioration of uniformity in a screen 3. Embodiment of the present disclosure 3-1. Transistor with Neuron MOS structure 3-1-1. Device structure 3-1-2. Operating principle 3-2. Example 1 (Example of a countermeasure against horizontal stripes: Example of using Neuron-MOS) 3-3. Example 2 (Modified example of Example 1) 3-4. Example 3 (Modified example of Example 1 / Example 2) 3-5. Example 4 (Modified example of Example 1: Example of controlling Back-Gate) 3-6. Example 5 (Modified example of Example 1: Example of controlling a dual gate) 4. Modified Example 5. Electronic equipment 5-1. Special Example 1 (Example of a digital camera) 5-2. Special Example 2 (Example of a Head-Mounted Display) 6. Configuration of the present disclosure <Anzeigeeinrichtung und elektronische Einrichtung gemäß der vorliegenden Offenbarung, Allgemeine Beschreibung>

[0015] In a display device and an electronic device according to the present disclosure, a control unit can be configured to set the threshold voltage of the driver transistor by controlling the gate voltage of the other gate electrode. Furthermore, the control unit can apply a predetermined DC voltage to the other gate electrode as a control voltage. The other gate electrode can be a back-gate or one of the gate electrodes of a dual-gate structure.

[0016] In the display device and the electronic device according to the present disclosure, including the advantageous configuration mentioned above, the control unit for controlling the gate voltage of the other gate electrode can be configured in units of pixel rows of the pixel array unit. Furthermore, the pixels, each containing the driver transistor which contains the multiple gate electrodes, can be arranged in even-numbered pixel rows, odd-numbered pixel rows, or all pixel rows of the pixel array unit, and the control unit can be configured to control the gate voltage of the other gate electrode in only the even-numbered, the odd-numbered, or all pixel rows.

[0017] Furthermore, in the display device and the electronic device according to the present disclosure, which include the aforementioned advantageous configuration, the pixels can each have a threshold voltage correction function by using an initialization voltage of the gate electrode to which the video signal is applied, of the driver transistor as a reference, and by changing the source voltage of the driver transistor to a voltage obtained by subtracting the threshold voltage of the driver transistor from the initialization voltage. Furthermore, the light emission unit can include an organic electroluminescent device. <Anzeigeeinrichtung, auf die die Technologie der vorliegenden Offenbarung angewandt ist> [System configuration]

[0018] First, a display device to which the technology of the present disclosure is applied, in particular an active matrix display device, is described. Fig. Figure 1 is a system configuration diagram that schematically shows a specific configuration of an active matrix display device to which the technology of the present disclosure is applied.

[0019] An active matrix display is a display device that controls a current flowing through an electro-optical device by means of an active device, for example, an isolated-gate field-effect transistor, provided in a pixel circuit that includes the electro-optical device. Typical examples of isolated-gate field-effect transistors include a MOS transistor and a TFT (thin-film transistor).

[0020] Here, an organic active matrix EL device, which uses an organic EL device, is described as an example of a pixel circuit's light emission unit (light emission device). The organic EL device is a current-driver-type electro-optic device (intrinsic light emission device) in which the light emission luminance is changed depending on the value of the current flowing through the device.

[0021] As in Fig. Figure 1 shows an organic EL display device 10 to which the technology of the present disclosure is applied, a pixel array unit 30 in which several pixels 20, each containing an organic EL device, are arranged two-dimensionally in a matrix pattern, and a driver circuit unit located around the pixel array unit 30. The driver circuit includes, for example, a write-scan unit 40, a first driver-scan unit 50, a second driver-scan unit 60, a signal output unit 70, and the like, mounted on a display field 80 that includes the pixel array unit 30, and drives each of the pixels 20 of the pixel array unit 30. It is noted that some or all of the write-scan unit 40, the first driver-scan unit 50, the second driver-scan unit 60, and the signal output unit 70 may be located outside the display field 80.

[0022] In this case, where the organic EL display device 10 supports color display, a pixel (unit pixel) as a unit for forming a color image comprises several subpixels. In this case, each of the subpixels corresponds to pixel 20 in Fig. 1. In particular, in the display device that supports a color display, one pixel includes three subpixels, i.e., one subpixel that emits red (R) light, one subpixel that emits green (G) light, and one subpixel that emits blue (B) light.

[0023] However, a single pixel is not limited to the combination of subpixels of the three primary colors (RGB), and a pixel can be configured by adding a subpixel of one color or subpixels of multiple colors to the subpixels of the three primary colors. More specifically, for example, a pixel can be configured by adding a subpixel that emits white (W) light to improve luminance, or a pixel can be configured by adding at least one subpixel that emits light of a complementary color to increase the color reproduction gamut.

[0024] In the pixel array unit 30, with reference to the arrangement of the pixels 20 in m rows and n columns, scan lines 31 (311 to 31) are m ), first driver lines 32 (321 to 32 m ) and second driver lines 33 (331 to 33) m) for the corresponding pixel row along the row direction (arrangement direction of the pixels in the pixel rows). Furthermore, signal lines 34 (341 to 34) are wired with respect to the arrangement of pixels 20 in m rows and n columns. n ) wired for the corresponding pixel columns along the column direction (arrangement direction of the pixels in the pixel columns).

[0025] Scan lines 311 to 31 m The first driver lines 321 to 321 are each connected to the output terminal in the corresponding row of the write-scan unit 40. The second driver lines 331 to 331 are each connected to the output terminal in the corresponding row of the first driver-scan unit 50. The second driver lines 331 to 331 are each connected to the output terminal in the corresponding row of the second driver-scan unit 60. The signal lines 341 to 34 nare each connected to the output terminal in the corresponding column of the signal output unit 70.

[0026] The write-scan unit 40 includes a shift register circuit and the like. When a signal voltage of a video signal is written to each pixel 20 of the pixel array unit 30, this write-scan unit 40 performs a so-called line sequence scan, which scans each pixel 20 of the pixel array unit 30 in units of lines in a sequence order by sequentially writing-scan signals WS (WS1 to WS2). m ) to scan lines 31 (311 to 31) m ) will be delivered.

[0027] The first driver scan unit 50 includes a shift register circuit and the like, similar to the write scan unit 40. The first driver scan unit 50 controls the light emission / non-light emission (switching off) of the pixels 20 by supplying initial control signals DS (DS1 to DS1). m) to the first driver lines 32 (321 to 32) m ) in synchronization with the line sequence scanning performed by the write-scan unit 40.

[0028] The second driver scan unit 60 includes a shift register circuit and the like, similar to the write scan unit 40. The second driver scan unit 60 controls the process of causing the pixels 20 to not emit light during the non-emission period by supplying second control signals AZ (AZ1 to AZ2). m ) to the second driver lines 33 (331 to 33) m ) in synchronization with the line sequence scanning performed by the write-scan unit 40.

[0029] The signal output unit 70 selectively outputs a signal voltage V sigof the video signal, which depends on the luminance information provided by a (not shown) signal supply source (hereinafter referred to in some cases for simplicity as the 'signal voltage'), and a reference voltage V ofs off. Here is the reference voltage V. ofs a voltage (e.g., a voltage corresponding to a black level of the video signal) as a reference for the signal voltage V sig of the video signal or a voltage close to it and used as an initialization voltage in a threshold voltage correction process, which will be described later.

[0030] The signal voltage V sig / the reference voltage V ofs , which are alternatively output by the signal output unit 70, are transmitted via the signal lines 34 (341 to 34) n) in units of pixel rows selected by the line sequence scan performed by the write-scan unit 40, written to pixel 20 of the pixel array unit 30. That is, the signal output unit 70 adopts a line sequence write driver mode in which the signal voltage V sig written in units of pixel lines (lines). [Pixel circuit]

[0031] Fig. Figure 2 is a circuit diagram showing a circuit example for the pixel (pixel circuit) 20 in the active matrix display device to which the technology of the present disclosure is applied. The light emission unit of the pixel 20 includes an organic EL device (organic electroluminescent device) 21 as an intrinsic light emission device.

[0032] As in Fig. As shown in Figure 2, pixel 20 includes the organic EL device 21 and a driver circuit that drives the organic EL device 21 by applying a current to it. A cathode electrode of the organic EL device 21 is connected to a cathode wiring 35 as a common power supply line, which is wired jointly for all pixels 20.

[0033] The driver circuit of the organic EL device 21 includes a driver transistor 22, a write transistor 23, a light emission control transistor 24, a switching transistor 25, a holding capacitor 26, and an auxiliary capacitor 27. Here, devices representing the pixel 20, i.e., the organic EL device 21, the driver transistor 22, the write transistor 23, the light emission control transistor 24, the switching transistor 25, the holding capacitor 26, and the auxiliary capacitor 27, are formed on a semiconductor substrate, such as a single-crystal silicon substrate as an example.

[0034] The driver transistor 22, the write transistor 23, the light emission control transistor 24, and the switching transistor 25 each contain a p-channel transistor and have a four-terminal structure (source / gate / drain) instead of three (source / gate / drain). Additionally, a power source voltage V is applied to the back-gates of transistors 22 to 25. cc created.

[0035] In the pixel 20 with the configuration mentioned above, the write transistor 23 writes the signal voltage V. sig into the gate electrode of the driver transistor 22 by sampling the signal voltage V sig , which is provided by the signal output unit 70 via signal line 34. The light emission control transistor 24 is connected between the power source line and the power source voltage V. ccand the source electrode of the driver transistor 22 and controls the light emission / non-light emission of the organic EL device 21 during driving by the first control signal DS. The switching transistor 25 is connected between the drain electrode of the driver transistor 22 and a current discharge target node (e.g., the cathode wiring 35) and controls the effect that the organic EL device 21 does not emit light during the light emission period while driving by the second control signals AZ.

[0036] The holding capacitor 26 is connected between the gate electrode and the source electrode of the driver transistor 22 and holds the signal voltage V. sig, which is written by the write transistor 23. The driver transistor 22 drives the organic EL device 21 by applying a driver current to the organic EL device 21, which depends on the holding voltage of the holding capacitor 26. The auxiliary capacitor 27 is located between the source electrode of the driver transistor 22 and a node with a fixed potential (e.g., the power source line of the power source voltage V). cc ) tied together. [Basic circuit operation]

[0037] The basic circuit operation of pixel 20 in the organic active matrix EL display device 10 with the configuration mentioned above will now be described.

[0038] It is noted that, since the write transistor 23, the light emission control transistor 24, and the switching transistor 25 are each p-channel transistors, the low-level and high-level states are active and inactive states, respectively, for the write-scan signal WS, the first control signal DS, and the second control signal AZ. Furthermore, the write transistor 23, the light emission control transistor 24, and the switching transistor 25 are each in a conductive state and a non-conductive state when the write-scan signal WS, the first control signal DS, and the second control signal AZ are in the active state or the inactive state, respectively.

[0039] While the reference voltage V ofsWhen the signal output unit 70 is output to the signal line 34, the write-scan signal WS first goes into the active state and the write transistor 23 goes into the conductive state, so that the reference voltage V ofs is written to the gate electrode. Accordingly, the gate voltage Vg of the driver transistor 22 becomes the reference voltage Vofs.

[0040] Furthermore, the first control signal DS is in a low-level state during the timing of the writing of the reference voltage Vofs, and the light emission control transistor 24 is in the conducting state. Consequently, the threshold voltage Vs of the driver transistor 22 becomes the power source voltage Vcc. At this time, the gate-source voltage Vgs of the driver transistor 22 satisfies the relationship Vgs = Vofs - Vcc.

[0041] To perform a threshold voltage correction process (threshold voltage correction processing), which will be described later, the gate-source voltage Vgs of the driver transistor 22 must be made greater than the threshold voltage Vth of the driver transistor 22. For this reason, each voltage value is adjusted so that the relationship |V gs |=|V ofs -V cc |>|V th | is fulfilled.

[0042] As described above, the initialization process involves setting the gate voltage V. g of the driver transistor 22 to the reference voltage V ofs and the source voltage V s of the driver transistor 22 to the power source voltage V cc A preparatory (threshold voltage correction preparation) process is performed before the next threshold voltage correction process. Therefore, the reference voltage V ofs and the power source voltage V ccan initialization voltage of the gate voltage V g of the driver transistor 22 or an initialization voltage of the source voltage V s of the driver transistor 22.

[0043] Next, when the first control signal DS transitions to the inactive state and the light emission control transistor 24 transitions to the non-conductive state, the source electrode of the driver transistor 22 transitions to a potential-free state and the threshold voltage correction process begins, while the gate voltage V g of the driver transistor 22 on the reference voltage V ofs is maintained. That is, the source voltage V s of the driver transistor 22 begins to reach a voltage (V g -V th ) to decrease, which is achieved by subtracting the threshold voltage V th from the gate voltage V g (=V ofs ) of the driver transistor 22 is obtained.

[0044] As described above, the process of changing the source voltage V s of the driver transistor 22 to a voltage (V ofs -V th ) which are obtained by subtracting the threshold voltage V th of the driver transistor 22 from the initialization voltage V ofs is obtained by using the initialization voltage V ofs The gate electrode of driver transistor 22 serves as a reference for the threshold voltage correction process. When this threshold voltage correction process occurs, a gate-source voltage V converges. gs of the driver transistor 22 ultimately to the threshold voltage V th of the driver transistor 22. This voltage, which is the threshold voltage V th The amount corresponds to a holding capacity of 26.

[0045] Then the write / scan signal WS transitions to the inactive state and the write transistor 23 transitions to the non-conductive state, thus completing the threshold voltage correction period. Afterwards, the signal voltage V sig of the video signal from the signal output unit 70 to the signal line 34 and the potential of the signal line 34 is determined by the reference voltage V ofs to the signal voltage V sig switched on.

[0046] Next, the write-scan signal WS transitions to the active state, causing the write transistor 23 to enter the conductive state and the signal voltage V to be applied. sig samples and then the sampled signal voltage V sig writes to pixel 20. This writing process involves the signal voltage V sig The gate voltage V is applied by the write transistor 23. g of the driver transistor 22 to the signal voltage V g .

[0047] At the time of writing the signal voltage V sig The auxiliary capacitor 27, which is located between the source electrode of the driver transistor 22 and the power source line of the power source voltage V, acts on the video signal. cc is connected to this, the change in source voltage V s to suppress the driver transistor 22. Then the threshold voltage V th of the driver transistor 22 at the time the driver transistor 22 is driven by the signal voltage V sig the video signal is canceled by the voltage that corresponds to the threshold voltage V th corresponds to the holding capacity of 26.

[0048] At this time, the gate-source voltage V gs of the driver transistor 22 as a function of the signal voltage V sig opened (increased). However, the source voltage V is sThe driver transistor 22 is still in a potential-free state. Therefore, the charges stored in the holding capacitor 26 are discharged according to the characteristics of the driver transistor 22. Then, the charging of the equivalent capacitance of the organic EL device 21 begins with the current flowing through the driver transistor 22 at that time.

[0049] Since the equivalent capacity of the organic EL device 21 is charged, the source voltage V s The voltage of driver transistor 22 gradually decreased over time. At this time, the variation in the threshold voltage V was th The driver transistor 22 is canceled for each pixel, and the drain-source current I depends on it. ds of the driver transistor 22 from a mobility µ of a semiconductor thin film that represents a channel of the driver transistor 22 (hereinafter referred to simply as "the mobility µ").

[0050] Here, the amount of a decrease in the source voltage V has an effect. s of the driver transistor 22 for discharging the charges stored in the holding capacitor 26. In other words, negative feedback to the holding capacitor was provided by the amount of a decrease (change) in the source voltage V. s of the driver transistor 22. Therefore, the amount of a decrease in the source voltage V is s of the driver transistor 22 to the feedback amount of the negative feedback.

[0051] As described above, by applying negative feedback to the holding capacitance 26, the feedback amount depends on the drain-source current I. ds , which flows through the driver transistor 22, it is possible to determine the dependence of the drain-source current I dsto cancel the mobility µ of the driver transistor 22. This cancellation process (cancellation processing) is a mobility correction process (mobility correction processing) of correcting the variation of the mobility µ of the driver transistor 22 for each pixel.

[0052] Since the drain-source current I ds increases when a signal amplitude V in (=V sig -V ofs As the amplitude of the video signal written to the gate electrode of driver transistor 22 increases, the absolute value of the negative feedback also increases. Therefore, the motion correction processing becomes dependent on the signal amplitude V. in of the video signal, i.e., the luminance level of the light emission. Furthermore, it is carried out in the case where the signal amplitude V inThe video signal is kept constant because the absolute value of the feedback amount of the negative feedback is increased when the mobility µ of the driver transistor 22 becomes larger, making it possible to remove the variation of the mobility µ for each pixel.

[0053] Then the write-scan signal WS transitions to the inactive state and the write transistor 23 transitions to the non-conductive state, so that the process (the processing) of writing the signal voltage and correcting the mobility is completed. Afterwards, the first control signal DS transitions to the inactive state and the light emission control transistor 24 transitions to the conductive state, so that current from the power source line at the power source voltage V is supplied. cc is supplied to the driver transistor 22 via the light emission control transistor 24.

[0054] At this time, because the write transistor 23 is in the non-conductive state, the gate electrode of the driver transistor 22 is electrically disconnected from the signal line 34 and is in a potential-free state. If the gate electrode of the driver transistor 22 is in a potential-free state because the holding capacitor 26 is connected between the gate and source of the driver transistor 22, the gate voltage V is applied here. g in synchronization with the change in source voltage V s The driver transistor 22 has been changed.

[0055] That is, the source voltage V s and the gate voltage V g The voltage of driver transistor 22 is increased, while the gate-source voltage V gs The holding capacity is maintained at 26. Then the source voltage V s of the driver transistor 22 to the light emission voltage V oledthe organic EL device 21 increases, which depends on the saturation current of the transistor.

[0056] As described above, the process involves the gate voltage V g of the driver transistor 22 in synchronization with the change in the source voltage V s The process of changing the gate voltage is called a bootstrap operation. In other words, the bootstrap operation is a process in which the gate voltage V is changed. g and the source voltage V s of the driver transistor 22 can be changed, while the gate-source voltage V gs , which is held in the holding capacitor 26, i.e., the voltage between both ends of the holding capacitor 26 is maintained.

[0057] Then the drain-source current I begins. ds of the driver transistor 22, to flow to the organic EL device 21, so that an anode voltage V ano of the organic EL device 21 as a function of the voltage I dsis increased. When the anode voltage V ano the organic EL device 21 finally the threshold voltage v thel When the voltage of the organic EL device 21 exceeds the threshold, the driving current begins to flow to the organic EL device 21. Consequently, the organic EL device 21 begins to emit light.

[0058] Meanwhile, during the non-light-emission period of the organic EL device 21, the second driver scan unit 60 brings the second control signal AZ into the active state and the switching transistor 25 into the conductive state. As the switching transistor 25 transitions to the conductive state, the drain electrode of the driver transistor 22 (anode electrode of the organic EL device 21) and the cathode wiring 35, as the current discharge target node, are electrically short-circuited by means of the switching transistor 25.

[0059] Here, the on-resistance of the switching transistor 25 is much smaller than that of the organic EL device 21. Therefore, during the non-light-emission period of the organic EL device 21, it is possible to force current flowing to the driver transistor 22 to flow to the cathode wiring 35, thus preventing current from flowing to the organic EL device 21. Furthermore, during the horizontal period, in which the threshold voltage correction and signal writing are performed, the second control signals AZ become active. However, during the subsequent light-emission period, the second control signals AZ are inactive.

[0060] The aforementioned organic EL display device 10, which uses the organic EL device 21, a self-emitting light-emitting device, as a light emission unit of the pixel 20, exhibits the following properties. That is to say, the organic EL display device 10, due to its excellent image quality (contrast), advantages in terms of thinning, application, and development with regard to a transparent display and a flexible display, and the like, compared to a liquid crystal display device, which is the same flat display device, holds great promise as a next-generation display. Furthermore, by configuring an organic EL on a semiconductor substrate, such as a single-crystal silicon substrate, applications have also been initiated for an electric viewfinder of a digital camera, a head-mounted display, and as an ultra-small display device.

[0061] Accordingly, in the organic EL display device 10, the number of component devices of the pixel 20 is greater than that of the liquid crystal display device. For example, the one in Fig. The pixel 20 shown comprises four transistors (22 to 25) and two capacitive devices (26 and 27) as its constituent devices. A large number of constituent devices in pixel 20 is detrimental to achieving high resolution. From this perspective, particularly in an organic EL display device formed on a semiconductor substrate, a novel approach arises: the wiring or similar components for driving pixel 20 are shared between adjacent pixel rows of the pixel array, i.e., between the odd-numbered and even-numbered pixel rows. This compresses the space of the display area (pixel array unit 30) to achieve high resolution. [Partial deterioration of uniformity in a screen]

[0062] As described above, if the wiring or similar is split between the odd-numbered pixel row and the even-numbered pixel row, a mirror-image structure is assumed in which the pixel structures of the odd-numbered row and the even-numbered row are symmetrical with respect to the boundary line between the even-numbered and odd-numbered rows. If the pixel structure of the odd-numbered row and the pixel structure of the even-numbered row are each a mirror-image structure, as described above, the following phenomena a) and b) occur.

[0063] a) In the production process, a generally in Fig. Figure 3A shows the use of oblique ion implantation. A difference (characteristic difference of driver transistor 22 between the odd-numbered row / the even-numbered row) in the properties (threshold voltage, mobility, and the like) of driver transistor 22 between the odd-numbered row / the even-numbered row occurs due to a deviation in ion implantation during the production process.

[0064] b) For example, the coupling potential between the odd-numbered row and the even-numbered row differs due to the shape difference between the pixel structure of the odd-numbered row and the pixel structure of the even-numbered row, which is caused by the masking deviation or the like (the coupling difference depends on the shape of the pixel structure).

[0065] As described above, pixel 20 in the general organic EL display device 10 has a function for correcting transistor characteristics, such as the threshold voltage V. th and the mobility µ, in units of pixels, and improves the uniformity, e.g., vertical stripes, by using this correction function. However, if only the correction function in units of pixels is performed, it is not sufficient to improve the uniformity for the effect of the characteristic difference of the driver transistor 22 between the odd-numbered row / even-numbered row described above and the coupling difference mentioned above, depending on the shape of the pixel structure. Consequently, as in Fig. Figure 3B shows a problem of partial deterioration of uniformity in the screen, e.g., horizontal stripes that occur due to the luminance difference between the odd / even line. <Ausführungsform der vorliegenden Offenbarung>

[0066] In one embodiment of the present disclosure, in order to enable the management of partial deterioration of uniformity that cannot be managed by the correction function performed in units of pixels, a transistor including the multiple gate electrodes is used as the driver transistor 22 of the pixel 20. Additionally, the organic EL device 21 is driven by applying a video signal to one of the gate electrodes of the multiple gate electrodes of the driver transistor 22, while the threshold voltage V thThe error of the driver transistor 22 is corrected by controlling the gate voltage of another gate electrode of the driver transistor.

[0067] Examples of the transistor including multiple gate electrodes include a transistor with a neuron-MOS structure and a dual-gate structure in a back-gate unit of a MOS transistor or a TFT (thin-film transistor). [Transistor with Neuron MOS structure]

[0068] Now, a transistor with a neuron-MOS structure is described. The equivalent circuit of the transistor with a neuron-MOS structure is shown in Fig. 4A shown. Fig. Figure 4A shows a p-channel neuron MOS on the left and an n-channel neuron MOS on the right. Furthermore, in Fig. 4B is a pixel circuit that uses a transistor with a p-channel neuron MOS structure, as shown by the driver transistor 22. (Device structure)

[0069] How Fig. As shown in Figure 4, in the transistor with a neuron-MOS structure, the gate electrode is in an electrically potential-free state, several gate electrodes (two gate electrodes G1 and G2 in this example) are provided on the side opposite the channel, and these gate electrodes G1 and G2 are capacitively connected to a potential-free gate G f coupled.

[0070] Furthermore, if the transistor with a neuron-MOS structure is used as the driver transistor 22, as in Fig. As shown in 4B, it is assumed that the signal voltage is V sig as gate voltage V1 applied to one gate electrode G1 and the control voltage V cont as gate voltage V2 of the other going electrode G2 is applied. (Operating principle)

[0071] In general, the voltage (potential-free gate voltage) Φ F of the potential-free gate G fof the transistor with a neuron-MOS structure by the weighted linear sum of the gate voltages V1, V2, ..., V n the multiple gate electrodes G1, G2, ..., G n against, which capacitively interacts with the potential-free gate G f are connected, as expressed by the following formula (1).

[0072] That is, assuming that the capacities between the potential-free gate G f and the gate electrodes G1, G2, ..., G n C1, C2, ..., C n are, the potential-free gate voltage Φ is satisfied F the following relationship. ΦF=C1V1+C2V2+⋯⋯+CnVnCtotalCtotal=∑i=0nCi It is noted that C total the sum of the capacities between the potential-free gate G f and the gate electrodes G1, G2 ..., G n represented.

[0073] Assuming the entry gate of the two in Fig. For the terminals shown in 4A (gate electrodes), formula (1) is expressed by the following formula (2). ΦF=C1V1+C2V2C1+C2

[0074] If this potential-free gate voltage Φ F the threshold voltage V th When the transistor's operating temperature exceeds the threshold, the transistor with a neuron-MOS structure transitions into the conductive state. Therefore, formula (2) can be expressed as the following formula (3). ΦF=C1V1+C2V2C1+C2>Vth

[0075] When this formula (3) is solved for the gate voltage V1, the following relationship is satisfied. V1>C1+C2C1Vth−C2C1V2 It is noted that formula (3) and formula (4) are satisfied in the case where the transistor with a neuron-MOS structure is an n-channel transistor.

[0076] Furthermore, assuming that the threshold voltage of the transistor, from the perspective of the gate electrode G1, is the gate voltage V1 V th1The following relationship has been established. Vth1=C1+C2C1Vth−C2C1V2

[0077] This shows that it is possible to determine the threshold voltage V th1 to freely control the transistor when in sight of the gate electrode G1 of the gate voltage V1, if an arbitrary voltage can be applied to the gate electrode G2 as the gate voltage V2.

[0078] The following describes a specific example of implementing partial correction in the screen to enable the management of partial deterioration of uniformity that cannot be handled by the correction function performed in units of pixels. [Example 1]

[0079] Example 1 is an example of a countermeasure against horizontal fringing that occurs due to the luminance difference between odd-numbered and even-numbered rows, which is generated by the characteristic difference of driver transistor 22 between the odd-numbered and even-numbered rows and the coupling difference depending on the shape of the pixel structure. The circuit diagram of the circuit configuration of a main part of an organic EL display device according to Example 1 is shown in Fig. 5 shown. In Fig. For the sake of simplicity, Figure 5 shows pixels 20 in the pixel arrangement of two rows and three columns for the pixel array unit 30. This also applies to the examples described later.

[0080] In Example 1, in the pixel arrangement of pixel array unit 30, the driver transistor 22 of pixel 20 in the odd-numbered row includes, for example, a transistor with a neuron-MOS structure in which two gate electrodes are provided. The driver transistor 22 of pixel 20 in the even-numbered row includes a normal p-channel transistor.

[0081] Furthermore, the signal voltage V is measured in pixel 20 in the odd-numbered row. sig A video signal is applied as the gate voltage V1 to a gate electrode of the driver transistor 22, which contains a neuron MOSFET. Furthermore, the control voltage V cont A predetermined DC voltage, the gate voltage V2, is applied from a control unit 90 to another gate electrode of the driver transistor 22 via a control line 36. The control unit 36 ​​is wired jointly between the control unit 90 and the pixels 20 in the odd-numbered rows.

[0082] The control unit 90 supplies the control voltage V cont A DC voltage of such a voltage value, which eliminates the luminance difference that occurs between the odd-numbered row and the even-numbered row, is applied to the other gate electrode of the driver transistor 22 of pixel 20 in the odd-numbered row due to the characteristic difference of the driver transistor 22 between the odd-numbered row and the even-numbered row and the coupling difference depending on the shape of the pixel structure. The voltage value of the control voltage V contis set to such a value that makes the luminance difference between the odd-numbered row / the even-numbered row small, preferably to zero, taking into account the characteristic difference of the driver transistor 22 between the odd-numbered row / the even-numbered row and the coupling difference depending on the shape of the pixel structure for each organic EL display device 10.

[0083] As described above, it is achieved by using a neuron-MOS as the driver transistor 22 of pixel 20 in the odd-numbered row and controlling the gate voltage V2 of the other gate electrode by the control voltage V cont possible, the threshold voltage V thto control the driver transistor 22, as can be seen from formula (5). Since luminance adjustment can be performed for each area (even-numbered row in this example) in the screen, it is possible to prevent horizontal fringing caused by the luminance difference between the odd-numbered and even-numbered rows. This fringing is generated by the characteristic difference of driver transistor 22 between the odd-numbered and even-numbered rows and the coupling difference, which depends on the shape of the pixel structure. Consequently, it is possible to improve the partial degradation of uniformity that cannot be addressed by the correction function performed in pixel units.

[0084] Therefore, adopting a configuration where the wiring or similar mechanism for driving pixel 20 is split between the odd-numbered and even-numbered rows, and where the pixel structure of the odd-numbered and even-numbered rows is a mirror image, does not result in a deterioration of uniformity, such as horizontal banding. Consequently, splitting the wiring or similar mechanism for driving pixel 20 between the odd-numbered and even-numbered rows makes it possible to compress the display area, thus contributing to high resolution. [Example 2]

[0085] Example 2 is a modified example of Example 1. A circuit diagram of a circuit configuration of a main part of an organic EL display device according to Example 2 is shown in Fig. Figure 6 is shown. In Example 1, a configuration is assumed where luminance adjustment is performed jointly for the odd-numbered rows. Meanwhile, in Example 2, a configuration is assumed where luminance adjustment is performed jointly for the even-numbered rows.

[0086] In example 2, in the pixel arrangement of pixel array unit 30, the driver transistor 22 of pixel 20 in the even-numbered row includes, for example, a transistor with a neuron-MOS structure in which two gate electrodes are provided. The driver transistor 22 of pixel 20 in the odd-numbered row includes a p-channel transistor with a single-gate structure.

[0087] At pixel 20 in the even-numbered row, the signal voltage V sigA video signal is applied as the gate voltage V1 to a gate electrode of the driver transistor 22, which contains a neuron MOSFET. Furthermore, the control voltage V cont A predetermined DC voltage, the gate voltage V2, is applied from control unit 90 to the other gate electrode of driver transistor 22 via control line 36. Control unit 36 ​​is wired between control unit 90 and the pixels 20 in the even-numbered rows.

[0088] The control unit 90 supplies the control voltage V contA DC voltage of such a voltage value, which eliminates the luminance difference that occurs between the odd-numbered row and the even-numbered row, is applied to the other gate electrode of the driver transistor 22 of pixel 20 in the even-numbered row due to the characteristic difference of the driver transistor 22 between the odd-numbered row and the even-numbered row and the coupling difference depending on the shape of the pixel structure. The voltage value of the control voltage V cont is set to a value that makes the luminance difference between the odd-numbered row / the even-numbered row small, preferably zero, similar to example 1.

[0089] According to Example 2 with the configuration mentioned above, it is possible to achieve the same operation and effect as in Example 1. That is, it is possible to prevent horizontal fringing due to the luminance difference between the odd and even rows, which is generated by the characteristic difference of driver transistor 22 between the odd and even rows and the coupling difference depending on the shape of the pixel structure, and to improve the partial deterioration of uniformity that cannot be handled by the correction function performed in pixel units. [Example 3]

[0090] Example 3 is a modified example of Example 1 / Example 2. A circuit diagram of a circuit configuration of a main part of an organic EL display device according to Example 3 is shown in Fig. Figure 7 shows the following configurations. Example 1 assumes a configuration where luminance adjustment is performed jointly for the odd-numbered rows. Example 2 assumes a configuration where luminance adjustment is performed jointly for the even-numbered rows. Meanwhile, Example 3 assumes a configuration where luminance adjustment is performed jointly for the odd-numbered rows and the even-numbered rows.

[0091] In example 3, the pixel arrangement of the pixel array unit 30 uses, for example, a transistor with a neuron-MOS structure, in which two gate electrodes are provided, as the driver transistor 22 for each of all pixels 20. In the pixel arrangement where the driver transistor 22 contains a neuron-MOS, a control voltage V is applied. cont1when the gate voltage V2 is applied from a control unit 91 to the other electrode of the driver transistor 22 in the odd-numbered row via the control line 36. Furthermore, the control voltage V cont2 when the gate voltage V2 is applied from a control unit 92 to the other gate electrode of the driver transistor 22 in the even-numbered row by means of a control line 37.

[0092] Each voltage value of the control voltage V cont1 and the control voltage V cont2 is set to such a value that makes the luminance difference between the odd-numbered row / the even-numbered row small, preferably to zero, taking into account the characteristic difference of the driver transistor 22 between the odd-numbered row / the even-numbered row and the coupling difference depending on the shape of the pixel structure for each organic EL display device 10.

[0093] According to Example 3, with the configuration mentioned above, it is also possible to achieve the same operation and effect as in Example 1 / Example 2. That is, it is possible to prevent horizontal fringing due to the luminance difference between the odd and even rows, which is generated by the characteristic difference of driver transistor 22 between the odd and even rows and the coupling difference depending on the shape of the pixel structure, and to improve the partial deterioration of uniformity that cannot be handled by the correction function performed in pixel units. Furthermore, according to Example 3, because the threshold voltage V thThe adjustment range of the luminance in both of the odd-numbered rows / even-numbered rows can be adjusted by the driver transistor 22 in both of the odd-numbered rows / even-numbered rows. [Example 4]

[0094] Example 4 is a modified example of Example 1. A circuit diagram of a circuit configuration of a main part of an organic EL display device according to Example 4 is shown in Fig. 8 shown. Example 1 is an example where the transistor with a neuron-MOS structure is used as the driver transistor 22, the signal voltage V sig a video signal is applied to one gate electrode and the gate voltage V2 of the other gate electrode is controlled.

[0095] Meanwhile, Example 4 is an example where a voltage of a back-gate is controlled in the driver transistor 22, which includes a transistor with a structure that incorporates the back-gate. Specifically, the control voltage V is applied to pixel 20 in the odd-numbered row. cont A predetermined DC voltage is applied as a back-gate voltage from the control unit 90 to a back-gate of the driver transistor 22, with a structure including the back-gate, via the control line 36. The control unit 36 ​​is wired jointly between the control unit 90 and the pixels 20 in the odd-numbered rows.

[0096] The control unit 90 supplies the control voltage V contA DC voltage of such a voltage value, which eliminates the luminance difference that occurs between the odd-numbered row and the even-numbered row, is applied to the back-gate of the driver transistor 22 of pixel 20 in the odd-numbered row, similar to the case of Example 1. The voltage value of the control voltage V cont is set to such a value that makes the luminance difference between the odd-numbered row / the even-numbered row small, preferably to zero, taking into account the characteristic difference of the driver transistor 22 between the odd-numbered row / the even-numbered row and the coupling difference depending on the shape of the pixel structure for each organic EL display device 10.

[0097] According to Example 4, with the configuration mentioned above, it is also possible to achieve the same operation and effect as in Example 1. That is, it is possible to prevent horizontal banding from occurring due to the luminance difference between the odd and even rows, which is generated by the characteristic difference of driver transistor 22 between the odd and even rows and the coupling difference depending on the shape of the pixel structure, and to improve the partial deterioration of uniformity that cannot be handled by the correction function performed in pixel units.

[0098] In example 4, where the luminance adjustment is performed jointly for the odd-numbered rows, a modified example of this could be a configuration where the luminance adjustment is performed jointly for the even-numbered rows, similar to example 2, or a configuration where the luminance adjustment is performed jointly for both of the odd / even-numbered rows, similar to example 3. [Example 5]

[0099] Example 5 is a modified example of Example 1. A circuit example of a pixel in an active-matrix display device to which Example 5 is applied is given in Fig. Figure 9 shows an example of an organic active matrix EL display device that uses an organic EL device as a light emission unit (light emission device) of a pixel circuit.

[0100] As in Fig. As shown in Figure 9, pixel 20 includes the organic EL device 21 and a driver circuit that drives the organic EL device 21 by applying a current to it. The driver circuit of the organic EL device 21 includes the driver transistor 22, the write transistor 23, and the hold capacitor 26.

[0101] Both the driver transistor 22 and the write transistor 23 can be an n-channel TFT. It should be noted that the combination of conductivity types of the driver transistor 22 and the write transistor 23 shown here is merely an example and is not limited to this. Here, it is assumed that the organic EL device 21, the driver transistor 22, and the holding capacitor 26 are formed on an insulator, such as a glass substrate, for example.

[0102] In the driver transistor 22, one electrode (source / drain electrode) is connected to the anode electrode of the organic EL device 21, and another electrode (source / drain electrode) is connected to a power supply line 38. Here, one electrode represents a metal wire electrically connected to one source / drain region, and the other electrode represents a metal wire electrically connected to another source / drain region. Furthermore, depending on the potential relationship between the two electrodes, one electrode may be a source electrode or a drain electrode in some cases, and the other electrode may be a drain electrode or a source electrode in other cases.

[0103] A power source potential DS, which is located between a first power source potential V ccp and a second power source potential V ini, which is lower than the first power source potential V ccp The potential that can be switched is supplied by a power supply scan unit 41 to the power supply line 38, to which the other electrode of the driver transistor 22 is connected, in synchronization with the line sequence scanning by the write scan unit 40. Switching this power supply potential DS controls the light emission / non-light emission (switching off) of pixel 20.

[0104] It is noted that, although the circuit configuration of 2Tr1C, which includes two transistors (Tr) of the driver transistor 22 and the write transistor 23 and a capacitive device (C) of the holding capacitance 26, has been illustrated here as the driver circuit of the organic EL device 21, the driver circuit is not limited to this.

[0105] In the organic EL display device with the configuration mentioned above, Example 5 is an example where a dual-gate TFT is used as the driver transistor 22 and one is controlled by a dual-gate.

[0106] An example of the cross-sectional structure of a dual-gate TFT, which is used as the driver transistor 22, is shown in Fig. Figure 10 shows that the dual-gate TFT comprises, for example, a lower gate electrode 82, a first gate insulating film 83, a semiconductor layer 84, a second gate insulating film 85, and an upper gate electrode 86 on a substrate 81 in the order shown. Furthermore, a region located between the lower gate electrode 82 and the upper gate electrode 86 in the semiconductor layer 84 is a channel region 841, and regions at both ends of this channel region are a source region 842 and a drain region 843. A source electrode 87 is electrically connected to the source region 842, and a drain electrode 88 is electrically connected to the drain region 843.

[0107] Example 5 is an example where a voltage is controlled at a gate electrode (e.g., the lower gate electrode 82) of the driver transistor 22, which incorporates the dual-gate TFT. A circuit configuration of a major part of an organic EL display device according to Example 5 is shown in Fig. 11 shown.

[0108] As in Fig. As shown in pixel 11, the control voltage V is located in pixel 20 in the odd-numbered row. cont A predetermined DC voltage, acting as a gate voltage, is applied by control unit 90 to a gate electrode of driver transistor 22, including the due-gate TFT, via control line 36. Control unit 36 ​​is wired between control unit 90 and pixel 20 in each odd-numbered row. The driver transistor 22 of pixel 20 in the even-numbered row contains a standard n-channel TFT.

[0109] The control unit 90 supplies the control voltage V contA DC voltage of such a voltage value, which eliminates the luminance difference that occurs between the odd-numbered row and the even-numbered row, is applied to the other gate electrode of the driver transistor 22, which is included in the due-gate TFT, of pixel 20 in the odd-numbered row, similar to the case of Example 1. The voltage value of the control voltage V cont is set to such a value that makes the luminance difference between the odd-numbered row / the even-numbered row small, preferably to zero, taking into account the characteristic difference of the driver transistor 22 between the odd-numbered row / the even-numbered row and the coupling difference depending on the shape of the pixel structure for each organic EL display device 10.

[0110] According to Example 5, with the configuration mentioned above, it is also possible to achieve the same operation and effect as in Example 1. That is, it is possible to prevent horizontal fringing due to the luminance difference between the odd and even rows, which is generated by the characteristic difference of driver transistor 22 between the odd and even rows and the coupling difference depending on the shape of the pixel structure, and to improve the partial deterioration of uniformity that cannot be handled by the correction function performed in pixel units.

[0111] In example 5, where the luminance adjustment is performed jointly for the odd-numbered rows, a modified example of this could be a configuration where the luminance adjustment is performed jointly for the even-numbered rows, similar to example 2, or a configuration where the luminance adjustment is performed jointly for both of the odd / even-numbered rows, similar to example 3. <Modifiziertes Beispiel>

[0112] The technology of the present disclosure is not limited to the embodiment mentioned above, and various modifications can be made without deviating from the core message of the present disclosure. For example, in Examples 1 to 4, a case in which the technology of the present disclosure is applied to a display device in which the device representing pixel 20 is formed on a semiconductor substrate, such as a single-crystal silicon substrate, was described as an example. However, the present technology of the present disclosure can equally be applied to a display device in which the device representing pixel 20 is formed on an insulator, such as a glass substrate. <Elektronische Einrichtung>

[0113] The display device mentioned above, as disclosed herein, can be used as a display unit (display device) of an electronic device in all areas where a video signal input into, or generated in, the electronic device is displayed as an image or video. Examples of electronic devices include a television, a laptop PC, a digital camera, a portable terminal device such as a mobile phone, and a head-mounted display. However, the electronic device is not limited to these.

[0114] By using the display device according to the present disclosure as a display unit of an electronic device in any field as described above, the following effects can be achieved. That is, according to the display device of the present disclosure, because the partial deterioration of uniformity, which cannot be overcome by the correction function performed in units of pixels, such as horizontal stripes that occur due to the luminance difference between the odd-numbered row and the even-numbered row, can be improved, it is possible to improve the image quality of the display unit.Since it is possible to prevent horizontal stripes from appearing due to the luminance difference between the odd-numbered row and the even-numbered row, the wiring or the like for driving the pixels between the odd-numbered row and the even-numbered row can also be divided, and the space of the display area can be compressed, thus realizing the high resolution of the display unit.

[0115] The display device of the present disclosure comprises a modular display device with a sealed configuration. For example, a display module formed by attaching a cover made of transparent glass or the like to a pixel array unit corresponds to the display device. It is noted that the display module may include a circuit unit for inputting / outputting signals or the like from outside to the pixel array unit, a flexible printed circuit (FPC), or the like. A digital camera and a head-mounted display are subsequently mentioned by way of example as specific examples of the electronic device that uses the display device of the present disclosure. It is noted that the specific examples described here are merely illustrative and the present disclosure is not limited to them. (Specific Example 1)

[0116] Fig. 12 is an external view of a digital single-lens reflex camera with interchangeable lenses, in which Fig. 12A shows a front view of it and Fig. Figure 12B shows a rear view of it. The digital camera of a single-lens reflex type with interchangeable lenses includes, for example, an interchangeable imaging lens unit (interchangeable lens) 112 on the right side of the front of a camera main body part (camera body) 111 and a grip part 113, to be grasped by a photographer, on the left side of the front of it.

[0117] Furthermore, a monitor 114 is provided essentially in the center of the rear of the camera's main body 111. An electronic viewfinder (eyepiece window) 115 is provided above the monitor 114. A photographer can visually perceive an optical image of a subject derived from the imaging lens unit 112 and can determine the composition by looking through the electronic viewfinder 115.

[0118] In the case of the interchangeable-lens reflex digital camera having the configuration described above, the display device of the present disclosure can be used as the electronic viewfinder 115 of the digital camera. In other words, the interchangeable-lens reflex digital camera according to this example is produced by using the display device of the present disclosure as the electronic viewfinder 115 of the digital camera. (Special Example 2)

[0119] Fig. Figure 13 is an external appearance view of a head-mounted display (a display worn on the head). The head-mounted display includes, for example, temple parts 212 on both sides of a spectacle-shaped display unit 211. The temple parts 412 are used to be attached to the head of a user. In this head-mounted display, the display device of the present disclosure can be used as the display unit 211 of the head-mounted display. In other words, the head-mounted display according to this example is produced by using the display device of the present disclosure as the display unit 211 of the head-mounted display. <Konfiguration der vorliegenden Offenbarung>

[0120] It should be noted that the present technology can also assume the following configurations. [1] A display device that includes the following: a pixel array unit, wherein the pixels are arranged in the pixel unit, each pixel containing a driver transistor comprising multiple gate electrodes and driving a light emission unit in response to a video signal applied to one of the gate electrodes; and a control unit that controls a gate voltage of another gate electrode of the driver transistor. [2] The display device according to [1] above, wherein the control unit corrects a threshold voltage of the driver transistor by controlling the gate voltage of the other electrode. [3] The display device according to [1] or [2] above, wherein The control unit applies a predetermined DC voltage to the other gate electrode as a control voltage. [4] Display device according to one of [1] to [3] above, wherein the other gate electrode is a back-gate. [5] The display device according to one of [1] to [3] above, wherein the other gate electrode is one of the gate electrodes of a dual-gate structure. [6] The display device according to one of [1] to [5] above, wherein The control unit controls the gate voltage of the other gate electrode in units of pixel rows of the pixel array unit. [7] The display device according to [6] above, wherein the pixels, each containing the driver transistor which contains the multiple gate electrodes, are arranged in even-numbered pixel rows, odd-numbered pixel rows or all pixel rows of the pixel array unit, and the control unit controls the gate voltage of the other gate electrode in only the even-numbered pixel rows, or the odd-numbered rows, or in all pixel rows. [8] The display device according to one of [1] to [7] above, wherein The pixels each have a threshold voltage correction function of using an initialization voltage of the gate electrode, to which the video signal is applied, of the driver transistor as a reference and changing the source voltage of the driver transistor to a voltage obtained by subtracting the threshold voltage of the driver transistor from the initialization voltage. [9] The display device according to one of [1] to [8] above, wherein The light emission unit includes an organic electroluminescence device.

[10] An electronic device that includes the following: a display device that includes the following: a pixel array unit, wherein the pixels are arranged in the pixel unit, each pixel containing a driver transistor comprising multiple gate electrodes and driving a light emission unit in response to a video signal applied to one of the gate electrodes, and a control unit that controls a gate voltage of another gate electrode of the driver transistor. Reference symbol list 10 organic EL display device 20 pixels 21 organic EL device 22 Driver transistor 23 Writer transistor 24 Light emission control transistor 25 Switching transistor 26 Holding capacity 27 Auxiliary capacity 30 pixel array unit 31 (311 to 31 m ) Scan line 32 (321 to 32 m ) first driver line 33 (331 to 33 m ) second driver line 34(341 to 34) n ) Signal line 35 Cathode wiring 36, 37 Control line 38 Power Source Supply Line 40 Write-Scan Unit 41 Power Source Supply Scan Unit 50 first driver scan unit 60 second driver scan unit 70 Signal output unit 80 Display field 90, 91, 92 Control unit

Claims

[1] Display device comprising the following: a plurality of pixels arranged in a pixel unit, each pixel comprising a light emission unit (21) and a driver transistor (22) comprising a first gate electrode (G1) and a second gate electrode (G2) and configured to drive the light emission unit in response to a video signal applied to the first gate electrode (G1), the driver transistor and the light emission unit being connected in series between a power supply line providing a power supply potential (Vcc) and a power source line (35) providing a cathode potential; and a control unit (90) designed to control the plurality of pixels in such a way that a voltage of the second gate electrode of the driver transistor is changed in order to adjust the luminance, wherein the second gate electrodes (G2) of each of the pixels in a row are connected to a common control line (36) which is coupled to the control unit and wherein the first and second gate electrodes are arranged on a side opposite a semiconductor layer of the driver transistor. [2] Display device according to claim 1, wherein the control unit (90) is configured to control the plurality of pixels such that the voltage of the second gate electrode of the driver transistor of each of the pixels in a row is changed in such a way that a luminance difference occurring between that row and an adjacent row is reduced or becomes zero. [3] Display device according to claim 1, wherein the first gate electrode is located above a semiconductor layer of the driver transistor and the second gate electrode is located below the semiconductor layer of the driver transistor. [4] Display device according to claim 1, wherein the driver transistor (22) has a third gate electrode (G F ) exhibits a capacitive coupling with the first and second gate electrodes. [5] Display device according to claim 1, wherein the control unit (90) is configured to correct the threshold voltage of the driver transistor by controlling the voltage of the second gate electrode. [6] Display device according to claim 1, wherein the control unit (90) is configured to apply a predetermined DC voltage to the second gate electrode. [7] Display device according to claim 1, wherein the second gate electrode is one of gate electrodes of a dual-gate structure. [8] Display device according to claim 1, wherein the control unit (90) is configured to control the voltage of the second gate electrode in units of pixel rows of the pixel array unit. [9] Display device according to claim 8, wherein the pixels, each comprising a driver transistor with a first gate electrode and a second gate electrode, are arranged in even-numbered pixel rows, odd-numbered pixel rows or all pixel rows of the pixel array unit, and the control unit (90) is configured to control the voltage of the second gate electrode in only the even-numbered pixel rows or the odd-numbered rows or in all pixel rows. [10] Display device according to claim 1, wherein the pixels each have a threshold voltage correction function of using an initialization voltage of the gate electrode to which the video signal is applied, of the driver transistor as a reference and of changing the source voltage of the driver transistor to a voltage obtained by subtracting the threshold voltage of the driver transistor from the initialization voltage. [11] Display device according to claim 1, wherein the light emission unit includes an organic electroluminescence device. [12] Electronic device comprising the following: a display device as defined in any of the preceding claims.

Images