Light emitting device, display, photoelectric conversion device, electronic apparatus, illumination device, and movable body

Abstract

To reduce the influence of voltage reduction on light emission.SOLUTION: A light emitting device comprises: a plurality of pixel circuits that each include a light emitting element emitting light with brightness according to a pixel signal; a drive circuit that selects a pixel circuit in which the pixel signals is written from the plurality of pixel circuits; and a plurality of power lines for supplying power supply voltage to the plurality of pixel circuits. The plurality of power lines include a power line extending in a first direction at a portion where it overlaps the plurality of pixel circuits. Two or less pixel circuits are selected by the drive circuit at the same timing from two or more pixel circuits arranged along the first direction, of the plurality of pixel circuits. Two or less pixel circuits are selected by the drive circuit at the same timing from two or more pixel circuits arranged along a second direction orthogonal to the first direction, of the plurality of pixel circuits.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a light-emitting device, a display device, a photoelectric conversion device, an electronic device, a lighting device, and a mobile object. [Background technology]

[0002] Patent Document 1 discloses a display device in which a photodetector element is provided in the vicinity of each light-emitting element arranged on a display surface, and the display device corrects the brightness of the light-emitting element while an image is being displayed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-024994 Summary of the Invention [Problem to be solved by the invention]

[0004] When a pixel signal with a large value is written to a pixel circuit, the power supply voltage supplied to the pixel circuits surrounding the pixel circuit may drop significantly. This voltage drop may cause the values of the pixel signals written to the surrounding pixel circuits to change, which may result in light not being emitted with the intended brightness. Some aspects of the present invention provide techniques for reducing the effect of the voltage drop on light emission. [Means for solving the problem]

[0005] According to some embodiments, there is provided a light-emitting device comprising: a plurality of pixel circuits, each including a light-emitting element that emits light of a luminance corresponding to a pixel signal; a drive circuit that selects a pixel circuit from the plurality of pixel circuits to which the pixel signal is to be written; and a plurality of power supply lines that supply a power supply voltage to the plurality of pixel circuits, wherein the plurality of power supply lines include power supply lines that extend in a first direction in a portion that overlaps with the plurality of pixel circuits, and wherein the number of pixel circuits selected by the drive circuit at the same timing from two or more pixel circuits arranged along the first direction among the plurality of pixel circuits is two or less, and the number of pixel circuits selected by the drive circuit at the same timing from two or more pixel circuits arranged along a second direction perpendicular to the first direction among the plurality of pixel circuits is two or less. [Effects of the Invention]

[0006] According to the above embodiment, the influence of a voltage drop on light emission is reduced. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a block diagram illustrating an example of the configuration of a light emitting device according to some embodiments. [Figure 2] FIG. 2 is an equivalent circuit diagram illustrating an example of the configuration of a pixel circuit according to some embodiments. [Figure 3] FIG. 2 is an equivalent circuit diagram illustrating an example of the configuration of a light-emitting circuit according to some embodiments. [Figure 4] FIG. 10 is a layout diagram illustrating an example of the configuration of power lines according to some embodiments. [Figure 5] 5A and 5B are schematic diagrams illustrating an example of the operation of a light-emitting circuit according to some embodiments. [Figure 6] FIG. 10 is an equivalent circuit diagram illustrating a modification of the light emitting circuit according to some embodiments. [Figure 7] 10A to 10C are diagrams illustrating modifications of light-emitting devices according to some embodiments. [Figure 8] FIG. 2 is a cross-sectional view showing an example of the configuration of a pixel circuit according to some embodiments. [Figure 9] FIG. 1 is a diagram illustrating an example of an image forming apparatus using a light emitting device according to some embodiments. [Figure 10] 1A and 1B are diagrams illustrating examples of display devices using light-emitting devices according to some embodiments. [Figure 11] 1A and 1B are diagrams illustrating an example of a photoelectric conversion device using a light-emitting device according to some embodiments. [Figure 12] 10A to 10C are diagrams illustrating examples of electronic devices using light-emitting devices according to some embodiments. [Figure 13] 1A and 1B are diagrams illustrating examples of display devices using light-emitting devices according to some embodiments. [Figure 14] 1A and 1B are diagrams illustrating an example of a lighting device using a light-emitting device according to some embodiments. [Figure 15] 1A and 1B are diagrams illustrating an example of a moving object using a light emitting device according to some embodiments. [Figure 16] FIG. 10 is a diagram illustrating an example of a wearable device using the light-emitting device according to some embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the invention claimed. Although multiple features are described in the embodiments, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0009] A light emitting device 100 according to some embodiments will be described with reference to Figures 1 to 7. The following embodiments are all examples of the present disclosure. The numerical values, shapes, materials, arrangement of components, and the like in the following description do not limit the present disclosure.

[0010] An example configuration of a light emitting device 100 will be described with reference to the block diagram of FIG. 1. The light emitting device 100 may be used to display a desired image or the like. The light emitting device 100 may include a plurality of pixel circuits 120, a drive circuit 110, and a signal processing circuit 102. The light emitting device 100 may further include a receiving circuit 101 and a memory 103. The light emitting device 100 may not include some of the components shown in FIG. 1, or may include components not shown in FIG. 1.

[0011] The pixel circuits 120 are arranged in a pixel region 121 to form a two-dimensional array. In FIG. 1, only one of the pixel circuits 120 is denoted by a reference symbol. In the following description, a set of two or more pixel circuits 120 arranged horizontally in FIG. 1 is referred to as a pixel row, and a set of two or more pixel circuits 120 arranged vertically in FIG. 1 is referred to as a pixel column. The pixel circuits 120 are arranged to form a plurality of pixel rows and a plurality of pixel columns. Each of the pixel circuits 120 emits light with a luminance corresponding to a supplied pixel signal. The pixel signal can take a value representing the luminance of light to be emitted by the pixel circuit 120. In the following description, the value taken by the pixel signal may be referred to as a signal value.

[0012] The drive circuit 110 writes pixel signals to each of the plurality of pixel circuits 120. As shown in FIG. 1, the drive circuit 110 may include a column select circuit 104, a column memory 105, a timing signal generator 106, a column digital-to-analog converter (DAC) 107, a column buffer 108, and row select circuits 109a and 109b.

[0013] The receiving circuit 101 receives display data supplied from outside the light emitting device 100 for display in the pixel region 121. The display data received by the receiving circuit 101 is supplied to the signal processing circuit 102. The memory 103 is connected to the signal processing circuit 102. The memory 103 is a memory area for temporarily storing the display data supplied from outside.

[0014] After display data for one frame is stored in the memory 103, the signal processing circuit 102 processes this display data for display in the pixel area 121. For example, the signal processing circuit 102 generates column drive data and signal value data by sorting the display data in order of light emission. The signal processing circuit 102 transfers the column drive data to the column selection circuit 104 and transfers the signal value data to the column memory 105. The column drive data and signal value data can be data for each pixel row in the pixel area 121, which includes a plurality of pixel circuits 120. The signal processing circuit 102 also sends a timing control signal to the timing signal generator 106 for controlling the timing of the operation of the drive circuit 110.

[0015] The column selection circuit 104 generates a selection signal for selecting pixel circuits 120 in a predetermined column for each pixel row based on the supplied column drive data. Furthermore, the column selection circuit 104 causes the column memory 105 to supply signal value data (hereinafter sometimes referred to as column data) corresponding to each pixel circuit 120 in the selected column from the signal value data supplied to the column memory 105 to the column DAC 107. In the following description, all of the signal value data supplied to the column memory 105 is supplied to the column DAC 107 for each pixel row. Alternatively, some of the signal value data supplied to the column memory 105 may be selected and supplied to the column DAC 107.

[0016] The column DAC 107 performs digital-to-analog conversion on the signal values of the column data supplied from the column memory 105 in accordance with a timing signal input from the timing signal generator 106. A pixel signal representing the signal value of the column data converted from a digital value to an analog value by the column DAC 107 is supplied to the pixel area 121 via the column buffer 108. The timing signal generator 106 supplies timing signals to the row selection circuits 109a and 109b. The row selection circuits 109a and 109b select a pixel circuit 120 from the plurality of pixel circuits 120 to which the pixel signal is to be written. The row selection circuits 109a and 109b generate selection signals synchronized with the column data in accordance with the supplied timing signal and supply the selection signals to the pixel circuits 120 selected from the plurality of pixel circuits 120. The signal value of the pixel signal is written to the pixel circuit 120 selected by the row selection circuits 109a and 109b from the plurality of pixel circuits 120. The pixel circuit 120 emits light with a brightness corresponding to the written signal value.

[0017] An example of the configuration of the pixel circuit 120 will be described with reference to the equivalent circuit diagram of Fig. 2. Each of the plurality of pixel circuits 120 included in the light-emitting device 100 may have the configuration of Fig. 2. The pixel circuit 120 includes a write transistor 201, a holding capacitor 202, a drive transistor 203, and a light-emitting element 204. The write transistor 201 and the drive transistor 203 are shown as P-channel transistors in Fig. 2. Alternatively, at least one of these transistors may be an N-channel transistor, or a configuration other than a transistor may be used.

[0018] The write transistor 201 is a transistor for controlling writing of a pixel signal to the pixel circuit 120 (specifically, the holding capacitor 202). One main terminal (the drain in the example of FIG. 2) of the write transistor 201 is connected to a signal line 205. The other main terminal (the source in the example of FIG. 2) of the write transistor 201 is connected to one terminal of the holding capacitor 202 and the gate of the drive transistor 203. The gate of the write transistor 201 is connected to a scanning line 206.

[0019] The holding capacitor 202 holds the pixel signal written to the pixel circuit 120. One terminal of the holding capacitor 202 is connected to one main terminal of the writing transistor 201 and the gate of the driving transistor 203. The other terminal of the holding capacitor 202 is connected to a power supply line 207. A power supply voltage (for example, VDD) is supplied to the power supply line 207.

[0020] The driving transistor 203 supplies a current corresponding to the value of the pixel signal (i.e., signal value) to the light-emitting element 204. One electrode (anode in the example of FIG. 2) of the light-emitting element 204 is connected to one main terminal (source in the example of FIG. 2) of the driving transistor 203. The other main terminal (drain in the example of FIG. 2) of the driving transistor 203 is connected to a power supply line 207. Other circuit elements may or may not be arranged in the signal path between the driving transistor 203 and the light-emitting element 204. Other circuit elements may or may not be arranged in the signal path between the driving transistor 203 and the power supply line 207.

[0021] One electrode (anode in the example of FIG. 2) of the light emitting element 204 is connected to one main terminal of the drive transistor 203. The other electrode (cathode in the example of FIG. 2) of the light emitting element 204 is connected to a ground line 208. A ground voltage is supplied to the ground line 208.

[0022] A pixel signal is supplied to the signal line 205 from the drive circuit 110 (specifically, the column buffer 108). In response to the supply of a selection signal to the scanning line 206, the write transistor 201 is turned on. In response to this, the pixel signal supplied to the signal line 205 is written to the holding capacitor 202. As a result, the light emitting element 204 emits light with a brightness corresponding to the pixel signal held in the holding capacitor 202. The pixel signal written to the holding capacitor 202 continues to be held even after the write transistor 201 is turned off. In this way, the selection signal is a signal for writing the pixel signal to the pixel circuit 120 (specifically, the holding capacitor 202).

[0023] An example configuration of the signal line 205, the scanning line 206, the power line 207, and the ground line 208 will be described with reference to the equivalent circuit diagram of FIG. 3. To explain the directions, a coordinate system CS consisting of an x-axis and a y-axis that are perpendicular to each other will be attached to the following drawings. The x-axis of the coordinate system CS will be simply referred to as the x-axis, and the y-axis of the coordinate system CS will be simply referred to as the y-axis. Furthermore, a direction that forms an angle of 45 degrees with each of the x-axis and the y-axis will be referred to as direction 303. A direction perpendicular to direction 303 will be referred to as direction 304.

[0024] The direction in which each of the multiple pixel rows extends is parallel to the x-axis direction, orthogonal to the y-axis direction, obliquely intersects with direction 303, and obliquely intersects with direction 304. The direction in which one pixel row extends may be the direction along which two or more pixel circuits 120 included in this pixel row are arranged. The direction in which each of the multiple pixel rows extends is parallel to the y-axis direction, orthogonal to the x-axis direction, obliquely intersects with direction 303, and obliquely intersects with direction 304. The direction in which one pixel column extends may be the direction along which two or more pixel circuits 120 included in this pixel column are arranged. The two directions intersecting obliquely may be such that the angle between the two directions is greater than 0 degrees and less than 90 degrees.

[0025] In the example of Fig. 3, 25 pixel circuits 120 are arranged in 5 rows and 5 columns. However, the numbers of pixel circuits 120, rows, and columns are not limited to these. The number of rows of pixel circuits 120 may be any number equal to or greater than 2. The number of columns of pixel circuits 120 may be any number equal to or greater than 2. Furthermore, the number of columns and the number of rows of pixel circuits 120 may be the same or different from each other.

[0026] The light emitting device 100 includes a plurality of signal lines 205. Pixel signals are supplied to a plurality of pixel circuits 120 through the plurality of signal lines 205. Each of the plurality of signal lines 205 is parallel to the y-axis direction. A separate signal line 205 is provided for each pixel column. Each signal line 205 is connected to two or more pixel circuits 120 included in the corresponding pixel column. One end of each signal line 205 is connected to a column buffer 108.

[0027] The light emitting device 100 includes a plurality of scanning lines 206. Selection signals are supplied to a plurality of pixel circuits 120 through the plurality of scanning lines 206. In FIG. 3, the plurality of scanning lines 206 are each assigned subscripts, such as scanning lines 206-1 to 206-9, to distinguish them from one another. The scanning lines 206-1 to 206-4 and 206-7 to 206-9 are each connected to two or more pixel circuits 120 arranged along a direction 304 among the plurality of pixel circuits 120. For example, the scanning line 206-1 is connected to the pixel circuit 120 located in the i-th row from the top and the i-th column from the left (where 1≦i≦5). The scanning line 206-2 is connected to the pixel circuit 120 located in the i+1-th row from the top and the i-th column from the left (where 1≦i≦4). The same applies to the other scanning lines 206. The scanning lines 206-5 to 206-6 are each connected to one pixel circuit 120. At least some of the multiple scanning lines 206 (specifically, scanning lines 206-1 to 206-4 and 206-7 to 206-9) include portions that obliquely intersect with both the x-axis direction and the y-axis direction. Specifically, these scanning lines 206 include portions that extend along direction 304.

[0028] One ends of the scanning lines 206-1 to 206-5 are connected to the row selection circuit 109a. One ends of the scanning lines 206-1 and 206-6 to 206-9 are connected to the row selection circuit 109b. In the example of FIG. 3, the scanning line 206-1 is connected to both the row selection circuit 109a and the row selection circuit 109b. Alternatively, the scanning line 206-1 may be connected to only one of the row selection circuit 109a and the row selection circuit 109b. In FIG. 3, the multiple scanning lines 206-2 to 206-9 are connected to only one of the two row selection circuits 109a and 109b. Alternatively, the multiple scanning lines 206-2 to 206-9 may be connected to both the two row selection circuits 109a and 109b. Furthermore, all of the scanning lines 206-1 to 206-9 may be connected to one of the two row selection circuits 109a and 109b, and the other of the two row selection circuits 109a and 109b may be omitted.

[0029] The light emitting device 100 includes a power supply line 207. The power supply line 207 is used to supply a power supply voltage to the plurality of pixel circuits 120. The power supply line 207 is connected to each of four electrode pads 301 arranged at the four corners of the light emitting device 100. A power supply voltage is supplied to the electrode pads 301 from outside the light emitting device 100. In the example of FIG. 3, the light emitting device 100 has four electrode pads 301. Alternatively, the light emitting device 100 may have one or more other number of electrode pads 301.

[0030] The light emitting device 100 includes a ground line 208. The ground line 208 is used to supply a ground voltage to the plurality of pixel circuits 120. The ground line 208 is connected to each of four electrode pads 302 arranged at the four corners of the light emitting device 100. The ground voltage is supplied to the electrode pads 302 from outside the light emitting device 100. In the example of FIG. 3, the light emitting device 100 has four electrode pads 302. Alternatively, the light emitting device 100 may have one or more other numbers of electrode pads 302.

[0031] A specific example of the configuration of the power supply line 207 will be described with reference to the layout diagram of Fig. 4. The ground line 208 may also have a layout similar to that of the power supply line 207. Fig. 4 shows the layout of the power supply line 207 at a position overlapping the pixel region 121.

[0032] 4, the power line 207 is made up of a plurality of power lines 401 and a plurality of power lines 402. The plurality of power lines 401 and the plurality of power lines 402 are connected to each other by a plurality of plugs 403. In FIG. 1, only one of the plurality of power lines 401, only one of the plurality of power lines 402, and only one of the plurality of plugs 403 are given a reference symbol.

[0033] Each of the multiple power supply lines 401 extends in the x-axis direction in a portion overlapping with the multiple pixel circuits 120. Each of the multiple power supply lines 402 extends in the y-axis direction in a portion overlapping with the multiple pixel circuits 120. The multiple power supply lines 401 are formed in one wiring layer, and the multiple power supply lines 402 are formed in another wiring layer. Either the wiring layer in which the multiple power supply lines 401 are formed or the wiring layer in which the multiple power supply lines 402 are formed may be arranged on the lower side (i.e., closer to the substrate). The multiple power supply lines 401 may be connected to the electrode pad 301 via another power supply line arranged outside the pixel region 121. The multiple power supply lines 402 may be connected to the electrode pad 301 via another power supply line arranged outside the pixel region 121.

[0034] One power supply line 401 may be connected to one pixel circuit 120 in each pixel column. Alternatively, one power supply line 401 may be connected to two or more pixel circuits 120 in each pixel column. The same applies to the power supply line 402.

[0035] 4, a grid-shaped power line 207 is formed by a plurality of power lines 401 and a plurality of power lines 402. Alternatively, either the plurality of power lines 401 or the plurality of power lines 402 may be omitted.

[0036] With reference to Fig. 5(a), the timing at which the drive circuit 110 (specifically, its row selection circuits 109a and 109b) selects the pixel circuits 120 will be described. As described above, a pixel signal is written to the pixel circuits 120 selected by the drive circuit 110. In Fig. 5(a), pixel circuits 120 selected at a certain timing are hatched, and pixel circuits 120 not selected at this timing are not hatched.

[0037] As shown in the upper left of FIG. 5( a), at a certain timing, the drive circuit 110 selects the pixel circuit 120 connected to the scanning line 206-1. As shown in the upper center of FIG. 5( a), at the next timing, the drive circuit 110 selects the pixel circuit 120 connected to either the scanning line 206-2 or the scanning line 206-6. As shown in the upper right of FIG. 5( a), at the next timing, the drive circuit 110 selects the pixel circuit 120 connected to either the scanning line 206-3 or the scanning line 206-7. As shown in the lower right of FIG. 5( a), at the next timing, the drive circuit 110 selects the pixel circuit 120 connected to either the scanning line 206-4 or the scanning line 206-8. As shown in the lower center of FIG. 5( a), at the next timing, the drive circuit 110 selects the pixel circuit 120 connected to either the scanning line 206-5 or the scanning line 206-9. By performing the above operations, one frame of display data is displayed. The driving circuit 110 can display moving images by repeating the above operations.

[0038] In the above-described operation, the number of pixel circuits 120 selected by the drive circuit 110 at the same timing from each pixel row is one or less (specifically, one for each). Furthermore, the number of pixel circuits 120 selected by the drive circuit 110 at the same timing from each pixel column is one or less (specifically, one for each). Therefore, two or more pixel circuits 120 selected at the same timing by the drive circuit 110 are distributed and connected to two or more power supply lines 401 or two or more power supply lines 402. This makes it possible to reduce the effect (e.g., smear) of a voltage drop caused by writing a large pixel signal to a specific pixel circuit 120 on the light emission of other pixel circuits 120.

[0039] The drive circuit 110 may select each pixel circuit 120 using an MLS (Multi Line Selection) method. For example, the drive circuit 110 may scan multiple pixel circuits 120 by selecting two pixel circuits 120 from each pixel column at each timing. The drive circuit 110 may change the pair of two pixel circuits 120 selected at the same timing from each pixel column for each frame. In the MLS method, the number of pixel circuits 120 selected at the same timing by the drive circuit 110 from each pixel row is two or less (specifically, two for each). Furthermore, the number of pixel circuits 120 selected at the same timing by the drive circuit 110 from each pixel column is two or less (specifically, two for each). Even in this case, the influence (e.g., smear) of a voltage drop caused by writing a large pixel signal to a specific pixel circuit 120 on the light emission of other pixel circuits 120 can be reduced.

[0040] 5(a), the lengths of the multiple scan lines 206 may be different from one another. Therefore, the drive circuit 110 may supply a selection signal with a higher driving strength to the longer scan line 206. For example, the drive circuit 110 may supply a selection signal with a higher driving strength to the scan line 206-1 than to the scan line 206-2.

[0041] 5(b), a description will be given of the connection configuration of the scanning lines 206 and the operation of the drive circuit 110 according to a modified example. In the example of FIG. 5(b), at least some of the multiple scanning lines 206 (specifically, scanning lines 206-2 to 206-6 and 206-8) include portions that obliquely intersect with both the x-axis direction and the y-axis direction. Specifically, these scanning lines 206 include a portion that extends along direction 303 and a portion that extends along direction 304.

[0042] The drive circuit 110 sequentially selects each pixel circuit 120 as shown in FIG. 5(b). In this operation, the number of pixel circuits 120 selected by the drive circuit 110 at the same time from each pixel row is two or less (specifically, one or two). Also, the number of pixel circuits 120 selected by the drive circuit 110 at the same time from each pixel column is one or less (specifically, one for each). In the configuration of FIG. 5(b), the scanning line 206-6 and the scanning line 206-8 may be connected, and the scanning line 206-7 and the scanning line 206-9 may be connected. In this case, one of the row selection circuit 109a and the row selection circuit 109b may be omitted.

[0043] With reference to Fig. 5(c), a description will be given of a connection configuration of the scanning lines 206 and an operation of the drive circuit 110 according to another modification. In the example of Fig. 5(c), at least some of the multiple scanning lines 206 (specifically, scanning lines 206-1 to 206-4 and 206-7) include portions that obliquely intersect with both the x-axis direction and the y-axis direction. Specifically, these scanning lines 206 include portions that extend along the direction 304. Furthermore, these scanning lines 206 include portions that extend along the x-axis direction.

[0044] The drive circuit 110 sequentially selects each pixel circuit 120 as shown in FIG. 5(c). In this operation, the number of pixel circuits 120 selected by the drive circuit 110 at the same time from each pixel row is two or less (specifically, one or two). Also, the number of pixel circuits 120 selected by the drive circuit 110 at the same time from each pixel column is one or less (specifically, one for each). In the configuration of FIG. 5(c), the scanning line 206-4 and the scanning line 206-6 may be connected, and the scanning line 206-5 and the scanning line 206-7 may be connected. In this case, one of the row selection circuit 109a and the row selection circuit 109b may be omitted.

[0045] An example of the configuration of the signal line 205, the scanning line 206, the power supply line 207, and the ground line 208 will be described with reference to the equivalent circuit diagram of Fig. 6. Duplicate explanations will be omitted for points that may be the same as those in the equivalent circuit diagram of Fig. 3.

[0046] The light emitting device 100 includes a plurality of scanning lines 206. Selection signals are supplied to a plurality of pixel circuits 120 through the plurality of scanning lines 206. In FIG. 6, the plurality of scanning lines 206 are each assigned a subscript, such as scanning lines 206-1 to 206-5, to distinguish them from one another. Each of the scanning lines 206-5 is connected to two or more pixel circuits 120 arranged along the x-axis direction among the plurality of pixel circuits 120. For example, the scanning line 206-1 is connected to the pixel circuits 120 located in the first row from the top. The scanning line 206-2 is connected to the pixel circuits 120 located in the second row from the top. The same applies to the other scanning lines 206. At least some of the plurality of scanning lines 206 (specifically, the scanning lines 206-1 to 206-5) include portions that obliquely intersect with both the direction 303 and the direction 304. Specifically, these scanning lines 206 include portions that extend along the x-axis direction.

[0047] One end of each of the scanning lines 206-1 to 206-5 is connected to the row selection circuit 109a. The row selection circuit 109b is omitted in the example of Fig. 6. Alternatively, the other end of each of the scanning lines 206-1 to 206-5 may be connected to the row selection circuit 109b.

[0048] 7(a), a specific configuration example of the power supply line 207 will be described. The ground line 208 may have a layout similar to that of the power supply line 207. FIG. 7(a) shows the layout of the power supply line 207 at a position overlapping the pixel region 121.

[0049] In the example of Fig. 7(a), the power line 207 is made up of a plurality of power lines 701 and a plurality of power lines 702. The plurality of power lines 701 and the plurality of power lines 702 are connected to each other by a plurality of plugs 703. In Fig. 1, only one of the plurality of power lines 701, only one of the plurality of power lines 702, and only one of the plurality of plugs 703 are given a reference symbol.

[0050] Each of the multiple power supply lines 701 extends in direction 303 in a portion overlapping with the multiple pixel circuits 120. Each of the multiple power supply lines 702 extends in direction 304 in a portion overlapping with the multiple pixel circuits 120. The multiple power supply lines 701 are formed in one wiring layer, and the multiple power supply lines 702 are formed in another wiring layer. Either the wiring layer in which the multiple power supply lines 701 are formed or the wiring layer in which the multiple power supply lines 702 are formed may be arranged on the lower side (i.e., closer to the substrate). The multiple power supply lines 701 may be connected to the electrode pad 301 via another power supply line arranged outside the pixel region 121. The multiple power supply lines 702 may be connected to the electrode pad 301 via another power supply line arranged outside the pixel region 121.

[0051] One power supply line 701 may be connected to one pixel circuit 120 in each pixel column. Alternatively, one power supply line 701 may be connected to two or more pixel circuits 120 in each pixel column. Also, one power supply line 701 may be connected to one pixel circuit 120 in each pixel row. Alternatively, one power supply line 701 may be connected to two or more pixel circuits 120 in each pixel row. The same applies to the power supply line 702.

[0052] 7(a), a grid-shaped power line 207 is formed by a plurality of power lines 701 and a plurality of power lines 702. Alternatively, either the plurality of power lines 701 or the plurality of power lines 702 may be omitted.

[0053] With reference to Fig. 7(b), the timing at which the drive circuit 110 (specifically, its row selection circuits 109a and 109b) selects the pixel circuits 120 will be described. As described above, a pixel signal is written to the pixel circuits 120 selected by the drive circuit 110. In Fig. 7(b), pixel circuits 120 selected at a certain timing are hatched, and pixel circuits 120 not selected at this timing are not hatched.

[0054] As shown in the upper left of FIG. 7(b), at a certain timing, the drive circuit 110 selects the pixel circuit 120 connected to the scanning line 206-1. As shown in the upper center of FIG. 7(b), at the next timing, the drive circuit 110 selects the pixel circuit 120 connected to the scanning line 206-2. As shown in the upper right of FIG. 7(b), at the next timing, the drive circuit 110 selects the pixel circuit 120 connected to the scanning line 206-3. As shown in the lower right of FIG. 7(b), at the next timing, the drive circuit 110 selects the pixel circuit 120 connected to the scanning line 206-4. As shown in the lower center of FIG. 7(b), at the next timing, the drive circuit 110 selects the pixel circuit 120 connected to the scanning line 206-5. By performing the above operations, one frame of display data is displayed. The drive circuit 110 can display moving images by repeating the above operations.

[0055] In the above-described operation, the number of pixel circuits 120 selected by the drive circuit 110 at the same timing from two or more pixel circuits arranged along the direction 303 among the plurality of pixel circuits 120 is one or less (specifically, one in each case). Also, the number of pixel circuits 120 selected by the drive circuit 110 at the same timing from two or more pixel circuits arranged along the direction 304 among the plurality of pixel circuits 120 is one or less (specifically, one in each case). Therefore, the two or more pixel circuits 120 selected at the same timing by the drive circuit 110 are distributed and connected to two or more power supply lines 701 or two or more power supply lines 702. This makes it possible to reduce the effect (e.g., smear) of a voltage drop caused by writing a large pixel signal to a specific pixel circuit 120 on the light emission of other pixel circuits 120.

[0056] The drive circuit 110 may select each pixel circuit 120 using the MLS method. In the MLS method, the number of pixel circuits 120 selected by the drive circuit 110 at the same time from each pixel row is two or less (specifically, two in each case). Also, the number of pixel circuits 120 selected by the drive circuit 110 at the same time from each pixel column is two or less (specifically, two in each case). Even in this case, the influence (e.g., smear) of a voltage drop caused by writing a large pixel signal to a specific pixel circuit 120 on the light emission of other pixel circuits 120 can be reduced.

[0057] Here, application examples in which the light emitting device 100 of this embodiment is applied to an image forming device, a display device, a photoelectric conversion device, an electronic device, a lighting device, a mobile object, and a wearable device will be described with reference to Figs. 8(a) and 8(b) to Figs. 16(a) and 16(b). The description will be made assuming that an organic light emitting element, such as an organic EL element using an organic light emitting material, is disposed in the pixel circuit 120 of the light emitting device 100. First, details of each component disposed in the pixel circuit 120 of the light emitting device 100 will be shown, and then application examples will be described.

[0058] An organic light-emitting device according to one embodiment of the present invention has a first electrode, a second electrode, and an organic compound layer disposed between these electrodes. One of the first electrode and the second electrode is an anode and the other is a cathode. In the organic light-emitting device of this embodiment, the organic compound layer may be a single layer or a laminate consisting of multiple layers, as long as it has an emitting layer. If the organic compound layer is a laminate consisting of multiple layers, the organic compound layer may include, in addition to the emitting layer, a hole injection layer, a hole transport layer, an electron blocking layer, a hole / exciton blocking layer, an electron transport layer, an electron injection layer, etc. The emitting layer may also be a single layer or a laminate consisting of multiple layers. If the emitting layer is a multi-layer, a charge generation layer may be disposed between the emitting layers. The charge generation layer may be composed of a compound having a lower LUMO than the hole transport layer, and the LUMO of the charge generation layer may be lower than the HOMO of the hole transport layer. Here, the molecular orbital energy of the organic compound layer may be the molecular orbital energy of the organic compound having the largest weight ratio in the organic compound layer.

[0059] Here, the closer the HOMO and LUMO are to the vacuum level, the higher they are described as being. The LUMO of the charge generation layer being lower than the HOMO of the hole transport layer means that the LUMO of the charge generation layer is closer to the vacuum level than the HOMO of the hole transport layer.

[0060] In this specification, the HOMO and LUMO can be calculated using molecular orbital calculations. The molecular orbital calculations are performed using density functional theory (DFT) or the like, with the functional being B3LYP and the basis set being 6-31G. *It is also the case that the range of graphical designs is Gaussian09(Gaussian09). ,RevisionC.01,MJFrisch,GWTrucks,HBSchlegel,GEScus area, MARobb, JRCheeseman, G. Scalmani, V. Barone, B. Mennucci, G. Petersson, H. Nakatsuji, M. Caricato, X. Li, HPHr atchian, AFIzmaylov, J. Bloino, G. Zheng, JLSonnenberg, M. Hada, M. Ehara, K. Toyota, R. Fukuda, J. Hasegawa, M. Ish ida,T.Nakajima,Y.Honda,O.Kitao,H.Nakai,T.Vreven,JAMontgomery,Jr.,JEPeralta,F.Ogliaro,M.Bearpark,JJH eyd, E. Brothers, KNKudin, VNStaroverov, T. Keith, R. Kobayashi, J. Normand, K. Raghavachari, A. Rendell, JCBuran t,SSIyengar,J.Tomasi,M.Cossi,N.Rega,JMMillam,M.Klene,JEKnox,JBCross,V.Bakken,C.Adamo,J.Jaramillo,R. Gomperts,REStratmann,O.Yazyev,AJAustin,R.Cammi,C.Pomelli,JWOchterski,RLMartin,K.Morokuma,VGZakrzews ki,GAVoth,P.Salvador,JJDannenberg,S.Dapprich,ADDaniels,O.Farkas,JBForesman,JVOrtiz,JCioslowski,and DJFox,Gaussian,Inc.,Wallingford CT,2010.)

[0061] The HOMO and LUMO in this specification can be calculated using the ionization potential and band gap. The HOMO can be estimated by measuring the ionization potential. The ionization potential can be measured by dissolving the compound to be measured in a solvent such as toluene and using a measuring device such as an AC-3. The band gap can be measured by dissolving the compound to be measured in a solvent such as toluene and irradiating it with excitation light. The band gap can be measured by measuring the absorption edge of the excitation light. Alternatively, the compound to be measured can be deposited on a substrate such as glass and irradiated with excitation light on the deposited film. The band gap can be measured by measuring the absorption edge of the absorption spectrum where the deposited film absorbs the excitation light.

[0062] The LUMO can be calculated using the band gap and ionization potential: subtracting the ionization potential from the band gap gives the LUMO.

[0063] The LUMO can also be estimated from the reduction potential. For example, the one-electron reduction potential can be estimated using CV (cyclic volmetry) measurements. CV measurements are performed, for example, in a 0.1 M tetrabutylammonium perchlorate solution in DMF, with an Ag / Ag reference electrode. + The LUMO can be estimated by adding -4.8 eV, the difference between the reduction potential of the compound and that of ferrocene, to the reduction potential of the compound obtained.

[0064] In the organic light-emitting device of one embodiment of the present invention, when the organic compound according to this embodiment is contained in the light-emitting layer, the light-emitting layer may be a layer consisting only of the organic compound according to this embodiment, or may be a layer consisting of the organometallic complex according to this embodiment and other compounds.

[0065] Structure of organic light-emitting element The organic light-emitting element is provided by forming an insulating layer, a first electrode, an organic compound layer, and a second electrode on a substrate. A protective layer, a color filter, a microlens, etc. may be provided on the cathode. When a color filter is provided, a planarizing layer may be provided between the protective layer and the color filter. The planarizing layer may be made of an acrylic resin, etc. The same applies when a planarizing layer is provided between the color filter and the microlens.

[0066] substrate Examples of the substrate include quartz, glass, silicon wafer, resin, and metal. Furthermore, the substrate may be provided with a switching element such as a transistor, a wiring pattern, and the like, and an insulating layer thereon. The insulating layer may be made of any material as long as it allows contact holes to be formed so that a wiring pattern can be formed between the first electrode and the substrate, and insulation from unconnected wiring patterns is ensured. For example, the insulating layer may be made of a resin such as polyimide, silicon oxide, silicon nitride, or the like.

[0067] electrode A pair of electrodes can be used as the electrodes. The pair of electrodes may be an anode and a cathode. When an electric field is applied in the direction in which the organic light-emitting element emits light, the electrode with a higher potential is the anode, and the other is the cathode. It can also be said that the electrode that supplies holes to the light-emitting layer is the anode, and the electrode that supplies electrons is the cathode.

[0068] The anode may be made of a material with a high work function. For example, simple metals such as gold, platinum, silver, copper, nickel, palladium, cobalt, selenium, vanadium, and tungsten, mixtures containing these metals, alloys of these metals, and metal oxides such as tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), and zinc indium oxide can be used. Conductive polymers such as polyaniline, polypyrrole, and polythiophene can also be used as the anode.

[0069] These electrode materials may be used alone or in combination of two or more. The anode may be composed of one layer or multiple layers.

[0070] When the electrode is used as a reflective electrode, for example, chromium, aluminum, silver, titanium, tungsten, molybdenum, or alloys thereof, or laminates thereof can be used. The above materials can also function as a reflective film without functioning as an electrode. Furthermore, when a transparent electrode is used as the electrode, a transparent conductive oxide layer such as indium tin oxide (ITO) or indium zinc oxide can be used, but is not limited to these. Photolithography technology can be used to form the electrode.

[0071] On the other hand, a material with a low work function may be selected as the cathode material. Examples include simple metals such as alkali metals (e.g., lithium), alkaline earth metals (e.g., calcium), aluminum, titanium, manganese, silver, lead, and chromium, as well as mixtures containing these metals. Alternatively, alloys combining these simple metals may be used. For example, magnesium-silver, aluminum-lithium, aluminum-magnesium, silver-copper, and zinc-silver may be used. Metal oxides such as indium tin oxide (ITO) may also be used. These electrode materials may be used alone or in combination. The cathode may have a single-layer or multi-layer structure. Silver may be used as the cathode, and a silver alloy may be used to reduce silver aggregation. The alloy ratio is not important as long as silver aggregation is reduced. For example, the silver:other metal ratio may be 1:1 or 3:1.

[0072] The cathode may be a top-emission element using an oxide conductive layer such as ITO, or a bottom-emission element using a reflective electrode such as aluminum (Al), and is not particularly limited. The method for forming the cathode is not particularly limited, but using a DC or AC sputtering method, for example, can provide good coverage of the formed film and reduce the resistance of the cathode.

[0073] Pixel isolation layer The pixel separation layer may be formed of silicon oxides such as silicon nitride (SiN), silicon oxynitride (SiON), or silicon oxide (SiO) formed using a chemical vapor deposition (CVD) method. To increase the in-plane resistance of the organic compound layer, the thickness of the organic compound layer, particularly the hole transport layer, may be thinned on the sidewalls of the pixel separation layer. Specifically, the thickness of the organic compound layer on the sidewalls can be thinned by increasing the taper angle of the sidewalls of the pixel separation layer or the thickness of the pixel separation layer, thereby increasing vignetting during deposition.

[0074] On the other hand, the sidewall taper angle and film thickness of the pixel separation layer can be adjusted to such an extent that voids are not formed in the protective layer formed thereon. By preventing voids from being formed in the protective layer, the occurrence of defects in the protective layer can be reduced. Since the occurrence of defects in the protective layer is reduced, deterioration of reliability such as the occurrence of dark spots and poor conduction of the second electrode can be reduced.

[0075] According to this embodiment, charge leakage to adjacent pixels can be effectively suppressed even if the taper angle of the sidewall of the pixel separation layer is not steep. As a result of this study, it was found that charge leakage can be sufficiently reduced if the taper angle is between 60 degrees and 90 degrees. The thickness of the pixel separation layer may be between 10 nm and 150 nm. Similar effects can also be achieved even if the pixel separation layer is composed only of pixel electrodes without a pixel separation layer. However, in this case, short circuits in organic light-emitting elements can be reduced by making the thickness of the pixel electrode less than half that of the organic layer or by making the edge of the pixel electrode forward tapered at less than 60 degrees.

[0076] Furthermore, even when the first electrode is a cathode and the second electrode is an anode, a wide color gamut and low-voltage operation are possible by forming an electron-transporting material and a charge-transporting layer, and an emitting layer on the charge-transporting layer.

[0077] organic compound layer The organic compound layer may be formed as a single layer or as multiple layers. When multiple layers are present, they may be referred to as hole injection layer, hole transport layer, electron blocking layer, light-emitting layer, hole blocking layer, electron transport layer, electron injection layer, etc., depending on their functions. The organic compound layer is primarily composed of organic compounds but may also contain inorganic atoms or compounds. The organic compound layer may contain, for example, copper, lithium, magnesium, aluminum, iridium, platinum, molybdenum, zinc, etc. The organic compound layer may be disposed between the first electrode and the second electrode, or may be disposed in contact with the first electrode and the second electrode. When multiple light-emitting layers are present, a charge generation section may be disposed between the first light-emitting layer and the second light-emitting layer. The charge generation section may contain an organic compound having a lowest unoccupied molecular orbital energy (LUMO) of -5.0 eV or less. The same applies when a charge generation section is disposed between the second light-emitting layer and the third light-emitting layer.

[0078] protective layer A protective layer may be provided on the cathode. For example, by adhering glass with a moisture absorbent on the cathode, the penetration of moisture and other contaminants into the organic compound layer can be reduced, thereby reducing the occurrence of display defects. In another embodiment, a passivation layer such as silicon nitride may be provided on the cathode to reduce the penetration of moisture and other contaminants into the organic compound layer. For example, after forming the cathode, the cathode may be transferred to another chamber without breaking the vacuum, and a 2 μm-thick silicon nitride may be formed by CVD to serve as a protective layer. After forming the protective layer by CVD, a protective layer may be formed by atomic layer deposition (ALD). The material of the protective layer formed by ALD is not limited, and may be silicon nitride, silicon oxide, aluminum oxide, or the like. Silicon nitride may be further formed by CVD on the protective layer formed by ALD. The protective layer formed by ALD may have a thickness smaller than that of the protective layer formed by CVD. Specifically, the thickness of the protective layer formed by ALD may be 50% or less, or even 10% or less, of the protective layer formed by CVD.

[0079] Color filters A color filter may be provided on the protective layer. For example, a color filter taking into consideration the size of the organic light-emitting element may be provided on another substrate, and the substrate on which the color filter is formed may be bonded to the substrate on which the organic light-emitting element is provided. Alternatively, for example, a color filter may be patterned on the above-mentioned protective layer using photolithography technology. The color filter may be made of a polymer.

[0080] planarization layer A planarization layer may be disposed between the color filter and the protective layer. The planarization layer is provided for the purpose of reducing the unevenness of the layers below the planarization layer. It may also be called a material resin layer without limiting the purpose. The planarization layer may be composed of an organic compound, and may be a low molecular weight or a high molecular weight. In consideration of reducing the unevenness, a high molecular weight organic compound may be used for the planarization layer.

[0081] The planarization layers may be provided above and below the color filter. In this case, the constituent materials of the planarization layers may be the same or different. Specific examples of the material for the planarization layer include polyvinyl carbazole resin, polycarbonate resin, polyester resin, ABS resin, acrylic resin, polyimide resin, phenol resin, epoxy resin, silicone resin, and urea resin.

[0082] Microlenses The organic light-emitting device may have an optical component such as a microlens on its light-emitting side. The microlens may be made of acrylic resin, epoxy resin, or the like. The microlens may be intended to increase the amount of light extracted from the organic light-emitting device or to control the direction of the extracted light. The microlens may have a hemispherical shape. When the microlens has a hemispherical shape, among the tangents to the hemisphere, there is a tangent that is parallel to the insulating layer, and the point of contact between this tangent and the hemisphere is the vertex of the microlens. The vertex of the microlens can be determined in the same way in any cross-sectional view. In other words, among the tangents to the semicircle of the microlens in the cross-sectional view, there is a tangent that is parallel to the insulating layer, and the point of contact between this tangent and the semicircle is the vertex of the microlens.

[0083] It is also possible to define the midpoint of a microlens. In the cross section of the microlens, a line segment is imagined from the point where an arc shape ends to the point where another arc shape ends, and the midpoint of this line segment can be called the midpoint of the microlens. The cross section for determining the vertex and midpoint may be a cross section perpendicular to the insulating layer.

[0084] The microlens has a first surface having a convex portion and a second surface opposite the first surface. The second surface can be disposed closer to the functional layer (light-emitting layer) than the first surface. To achieve this configuration, it is necessary to form the microlens on the light-emitting device. If the functional layer is an organic layer, high-temperature processes can be avoided in the microlens manufacturing process. Furthermore, when the second surface is disposed closer to the functional layer than the first surface, the glass transition temperatures of the organic compounds constituting the organic layer may all be 100°C or higher, and are preferably, for example, 130°C or higher.

[0085] Counter substrate An opposing substrate may be disposed on the planarization layer. The opposing substrate is called an opposing substrate because it is provided at a position corresponding to the aforementioned substrate. The opposing substrate may be made of the same material as the aforementioned substrate. When the aforementioned substrate is defined as a first substrate, the opposing substrate may be a second substrate.

[0086] organic layer The organic compound layers (hole injection layer, hole transport layer, electron blocking layer, light-emitting layer, hole blocking layer, electron transport layer, electron injection layer, etc.) constituting the organic light-emitting element according to an embodiment of the present disclosure may be formed by the following method.

[0087] The organic compound layer constituting the organic light-emitting device according to the embodiment of the present disclosure can be formed by dry processes such as vacuum deposition, ionization deposition, sputtering, plasma, etc. Alternatively to the dry process, a wet process can be used in which the compound is dissolved in an appropriate solvent and a layer is formed by a known coating method (e.g., spin coating, dipping, casting, LB method, inkjet method, etc.).

[0088] Here, when a layer is formed by a vacuum deposition method or a solution coating method, crystallization is unlikely to occur and the layer has excellent stability over time. When a film is formed by a coating method, the film can be formed by combining the film with an appropriate binder resin.

[0089] Examples of the binder resin include, but are not limited to, polyvinylcarbazole resin, polycarbonate resin, polyester resin, ABS resin, acrylic resin, polyimide resin, phenol resin, epoxy resin, silicone resin, and urea resin.

[0090] These binder resins may be used singly or in combination as homopolymers or copolymers, and may further contain known additives such as plasticizers, antioxidants, and ultraviolet absorbers, as needed.

[0091] Pixel circuit The light-emitting device may have a pixel circuit connected to the light-emitting element. The pixel circuit may be an active matrix type that controls the light emission of the first light-emitting element and the second light-emitting element independently. The active matrix type circuit may be voltage-programmed or current-programmed. The drive circuit has a pixel circuit for each pixel. The pixel circuit may have a light-emitting element, a transistor that controls the light-emission luminance of the light-emitting element, a transistor that controls the light-emission timing, a capacitor that holds the gate voltage of the transistor that controls the light-emission luminance, and a transistor for connecting the element to GND without going through the light-emitting element.

[0092] The light-emitting device has a display region and a peripheral region arranged around the display region. The display region has pixel circuits, and the peripheral region has a display control circuit. The mobility of a transistor constituting the pixel circuit may be lower than the mobility of a transistor constituting the display control circuit.

[0093] The slope of the current-voltage characteristics of the transistors that make up the pixel circuit may be smaller than the slope of the current-voltage characteristics of the transistors that make up the display control circuit. The slope of the current-voltage characteristics can be measured using the so-called Vg-Ig characteristics.

[0094] The transistors that make up the pixel circuit are transistors connected to light-emitting elements such as the first light-emitting element.

[0095] pixel An organic light emitting device includes a plurality of pixels, each of which includes sub-pixels that emit different colors, for example, RGB colors.

[0096] A pixel has an area called a pixel aperture that emits light. The pixel aperture may be 15 μm or less, or 5 μm or more. More specifically, it may be 11 μm, 9.5 μm, 7.4 μm, 6.4 μm, etc.

[0097] The spacing between the subpixels may be 10 μm or less, and specifically may be 8 μm, 7.4 μm, or 6.4 μm.

[0098] The pixels may be arranged in a known manner in a plan view. For example, they may be in a stripe arrangement, a delta arrangement, a pentile arrangement, or a Bayer arrangement. The shape of the subpixels in a plan view may be any known shape. For example, they may be rectangular, quadrilaterals such as diamonds, or hexagons. Of course, a shape that is close to a rectangle, rather than an exact shape, is included in the rectangle. The shape of the subpixels and the pixel arrangement may be used in combination.

[0099] Uses of the organic light-emitting device according to embodiments of the present disclosure The organic light-emitting device according to the embodiment of the present disclosure can be used as a component of a display device or a lighting device, and can also be used as an exposure light source for an electrophotographic image forming device, a backlight for a liquid crystal display device, or a light-emitting device having a white light source and a color filter.

[0100] The display device may be an image information processing device that has an image input unit that inputs image information from an area CCD, linear CCD, memory card, etc., has an information processing unit that processes the input information, and displays the input image on the display unit.

[0101] The display unit of the imaging device or inkjet printer may have a touch panel function. The driving method of this touch panel function may be an infrared method, a capacitance method, a resistive film method, or an electromagnetic induction method, and is not particularly limited. The display device may also be used in the display unit of a multifunction printer.

[0102] Next, further explanation will be given with reference to the drawings. FIG. 8(a) shows an example of a pixel circuit 120 arranged in a light-emitting device 100. The pixel has sub-pixels 810 (pixel circuits 120). The sub-pixels are divided into 810R, 810G, and 810B based on their light emission. The emitted colors may be distinguished by the wavelength of light emitted from the light-emitting layer, or the light emitted from the sub-pixels may be selectively transmitted or color-converted using a color filter or the like. Each sub-pixel has, on an interlayer insulating layer 801, a reflective electrode 802 serving as a first electrode, an insulating layer 803 covering the edge of the reflective electrode 802, an organic compound layer 804 covering the first electrode and the insulating layer, a transparent electrode 805 serving as a second electrode, a protective layer 806, and a color filter 807.

[0103] A transistor and a capacitor may be disposed below or inside the interlayer insulating layer 801. The transistor and the first electrode may be electrically connected via a contact hole or the like (not shown).

[0104] The insulating layer 803 may also be called a bank or a pixel separation film. The insulating layer 803 covers the edges of the first electrode and is disposed to surround the first electrode. The portion of the first electrode not covered by the insulating layer 803 contacts the organic compound layer 804 and becomes the light-emitting region.

[0105] The organic compound layer 804 includes a hole injection layer 841 , a hole transport layer 842 , a first light-emitting layer 843 , a second light-emitting layer 844 , and an electron transport layer 845 .

[0106] The second electrode may be a transparent electrode, a reflective electrode, or a semi-transparent electrode.

[0107] The protective layer 806 reduces the penetration of moisture into the organic compound layer. Although the protective layer is illustrated as a single layer, it may be a multi-layer structure. Each layer may be an inorganic compound layer and an organic compound layer.

[0108] The color filters 807 are divided into 807R, 807G, and 807B depending on their colors. The color filters may be formed on a planarization film (not shown). A resin protective layer (not shown) may be disposed on the color filters. The color filters may be formed on a protective layer 806. The color filters may be provided on an opposing substrate such as a glass substrate and then bonded thereto.

[0109] The display device 800 in FIG. 8(b) (corresponding to the light-emitting device 100 described above) includes an organic light-emitting element 826 and a TFT 818 as an example of a transistor. A substrate 811 made of glass, silicon, or the like is provided with an insulating layer 812 on top of it. An active element such as the TFT 818 is disposed on the insulating layer, and a gate electrode 813, a gate insulating film 814, and a semiconductor layer 815 of the active element are disposed on top of it. The TFT 818 also includes the semiconductor layer 815, a drain electrode 816, and a source electrode 817. An insulating film 819 is provided on top of the TFT 818. An anode 821 constituting the organic light-emitting element 826 and the source electrode 817 are connected via a contact hole 820 provided in the insulating film.

[0110] The electrical connection between the electrodes (anode, cathode) included in the organic light-emitting element 826 and the electrodes (source electrode, drain electrode) included in the TFT is not limited to the embodiment shown in Figure 8(b). In other words, it is sufficient that either the anode or the cathode is electrically connected to either the TFT source electrode or the drain electrode. TFT stands for thin film transistor.

[0111] 8(b), the organic compound layer 822 is illustrated as a single layer, but may be a multi-layer organic compound layer 822. A first protective layer 824 and a second protective layer 825 are provided on the cathode 823 to reduce deterioration of the organic light-emitting element.

[0112] In the display device 800 of FIG. 8(b), transistors are used as switching elements, but other switching elements may be used instead.

[0113] Furthermore, the transistors used in the display device 800 of Fig. 8(b) are not limited to transistors using single-crystal silicon wafers, but may also be thin-film transistors having an active layer on an insulating surface of a substrate. Examples of active layers include single-crystal silicon, amorphous silicon, microcrystalline silicon, and other non-single-crystal silicon, as well as non-single-crystal oxide semiconductors such as indium zinc oxide and indium gallium zinc oxide. Thin-film transistors are also called TFT elements.

[0114] The transistors included in the display device 800 of Figure 8(b) may be formed within a substrate such as a silicon substrate. Here, "formed within a substrate" means that the substrate itself, such as a silicon substrate, is processed to form the transistors. In other words, having a transistor within a substrate can also be seen as the substrate and the transistor being formed integrally.

[0115] The organic light-emitting element according to this embodiment has its light emission brightness controlled by a TFT, which is an example of a switching element. By providing multiple organic light-emitting elements on a surface, an image can be displayed based on the respective light emission brightnesses. Here, the switching element according to this embodiment is not limited to a TFT, but may also be a transistor formed from low-temperature polysilicon or an active matrix driver formed on a substrate such as a silicon substrate. "On the substrate" can also be referred to as "inside the substrate." Whether to provide a transistor in the substrate or to use a TFT is determined by the size of the display unit. For example, if the size is about 0.5 inches, the organic light-emitting element may be provided on a silicon substrate.

[0116] 9(a) to 9(c) are schematic diagrams showing an example of an image forming apparatus using the light emitting device 100 of this embodiment. The image forming apparatus 926 shown in Fig. 9(a) includes a photoconductor 927, an exposure light source 928, a developing unit 931, a charging unit 930, a transfer unit 932, a transport unit 933 (a transport roller in the configuration of Fig. 9(a)), and a fixing unit 935.

[0117] Light 929 is emitted from an exposure light source 928, and an electrostatic latent image is formed on the surface of a photoconductor 927. The light emitting device 100 can be applied to this exposure light source 928. A developing unit 931 contains toner or the like as a developer and can function as a developing device that applies the developer to the exposed photoconductor 927. A charging unit 930 charges the photoconductor 927. A transfer unit 932 transfers the developed image to a recording medium 934. A transport unit 933 transports the recording medium 934. The recording medium 934 can be, for example, paper or film. A fixing unit 935 fixes the image formed on the recording medium.

[0118] 9(b) and 9(c) are schematic diagrams showing an exposure light source 928 in which a plurality of light-emitting sections 936 are arranged along the longitudinal direction of a long substrate. The light-emitting device 100 can be applied to this light-emitting section 936. That is, a plurality of pixel circuits 120 are arranged along the longitudinal direction of the substrate. A direction 937 is parallel to the axis of the photoconductor 927. This column direction is the same as the axial direction of the photoconductor 927 when it rotates. This direction 937 can also be called the long axis direction of the photoconductor 927.

[0119] FIG. 9(b) shows a configuration in which the light-emitting units 936 are arranged along the longitudinal direction of the photoconductor 927. FIG. 9(c) shows a modified configuration of the arrangement of the light-emitting units 936 shown in FIG. 9(b), in which the light-emitting units 936 are arranged alternately in the column direction in each of the first and second columns. The light-emitting units 936 are arranged at different positions in the row direction in the first and second columns. In the first column, multiple light-emitting units 936 are arranged at intervals, and in the second column, multiple light-emitting units 936 are arranged at positions corresponding to the gaps between the light-emitting units 936 in the first column. The multiple light-emitting units 936 are also arranged at intervals in the row direction. The arrangement of the light-emitting units 936 shown in FIG. 9(c) can be described as, for example, a grid-like arrangement, a houndstooth arrangement, or a checkerboard pattern.

[0120] FIG. 10 is a schematic diagram illustrating an example of a display device using the light-emitting device 100 of this embodiment. The display device 1000 may include a touch panel 1003, a display panel 1005, a frame 1006, a circuit board 1007, and a battery 1008 between an upper cover 1001 and a lower cover 1009. The touch panel 1003 and the display panel 1005 are connected to flexible printed circuits FPCs 1002 and 1004. Active elements such as transistors are disposed on the circuit board 1007. The battery 1008 may not be disposed if the display device 1000 is not a portable device, and even if it is a portable device, it does not need to be disposed in this position. The light-emitting device 100 can be applied to the display panel 1005. The pixel circuits 120 disposed in the light-emitting device 100 functioning as the display panel 1005 are connected to active elements such as transistors disposed on the circuit board 1007 and operate.

[0121] The display device 1000 shown in FIG. 10 may be used as a display unit of a photoelectric conversion device (which may also be called an imaging device) that has an optical unit with multiple lenses and an imaging element that receives light that has passed through the optical unit and photoelectrically converts it into an electrical signal. The photoelectric conversion device may have a display unit that displays information acquired by the imaging element. The display unit may be a display unit exposed to the outside of the photoelectric conversion device or a display unit located within a viewfinder. The photoelectric conversion device may be a digital camera or a digital video camera.

[0122] FIG. 11 is a schematic diagram illustrating an example of a photoelectric conversion device using the light-emitting device 100 of this embodiment. The photoelectric conversion device 1100 may include a viewfinder 1101, a rear display 1102, an operation unit 1103, and a housing 1104. The photoelectric conversion device 1100 may also be called an imaging device. The light-emitting device 100 of this embodiment can be applied to the viewfinder 1101 or the rear display 1102, which are display units. In this case, the light-emitting device 100 may display not only an image to be captured, but also environmental information, imaging instructions, and the like. The environmental information may include the intensity of external light, the direction of external light, the moving speed of the subject, the possibility that the subject will be blocked by an obstruction, and the like.

[0123] Since the timing suitable for capturing an image is often very short, it is better to display information as soon as possible. Therefore, a light emitting device 100 provided with pixel circuits 120 including light emitting elements using organic light emitting materials such as organic EL elements may be used in a viewfinder 1101 or a rear display 1102. This is because organic light emitting materials have a fast response speed. A light emitting device 100 using an organic light emitting material is more suitable than a liquid crystal display device for these devices, which require a high display speed.

[0124] The photoelectric conversion device 1100 has an optical section (not shown). The optical section has multiple lenses, which form an image on a photoelectric conversion element (not shown) housed in a housing 1104 that receives light that has passed through the optical section. The focus of the multiple lenses can be adjusted by adjusting their relative positions. This operation can also be performed automatically.

[0125] The light emitting device 100 may be applied to a display unit of an electronic device. In this case, the light emitting device 100 may have both a display function and an operation function. Examples of the portable terminal include a mobile phone such as a smartphone, a tablet, and a head-mounted display.

[0126] FIG. 12 is a schematic diagram showing an example of an electronic device using the light-emitting device 100 of this embodiment. The electronic device 1200 has a display unit 1201, an operation unit 1202, and a housing 1203. The housing 1203 may have a circuit, a printed circuit board having the circuit, a battery, and a communication unit. The operation unit 1202 may be a button or a touch panel type reaction unit. The operation unit 1202 may be a biometric recognition unit that recognizes a fingerprint to perform unlocking or the like. A portable device having a communication unit can also be called a communication device. The light-emitting device 100 of this embodiment can be applied to the display unit 1201.

[0127] 13(a) and 13(b) are schematic diagrams illustrating an example of a display device using the light-emitting device 100 of this embodiment. FIG. 13(a) illustrates a display device such as a television monitor or a PC monitor. The display device 1300 has a frame 1301 and a display unit 1302. The light-emitting device 100 of this embodiment can be applied to the display unit 1302. The display device 1300 may have a base 1303 that supports the frame 1301 and the display unit 1302. The base 1303 is not limited to the form shown in FIG. 13(a). For example, the bottom edge of the frame 1301 may also serve as the base 1303. The frame 1301 and the display unit 1302 may be curved. The radius of curvature may be 5000 mm or more and 6000 mm or less.

[0128] FIG. 13(b) is a schematic diagram illustrating another example of a display device using the light-emitting device 100 of this embodiment. The display device 1310 of FIG. 13(b) is configured to be bendable and is a so-called foldable display device. The display device 1310 has a first display unit 1311, a second display unit 1312, a housing 1313, and a bending point 1314. The light-emitting device 100 of this embodiment can be applied to the first display unit 1311 and the second display unit 1312. The first display unit 1311 and the second display unit 1312 may be a single display unit without any joints. The first display unit 1311 and the second display unit 1312 can be separated by the bending point. The first display unit 1311 and the second display unit 1312 may display different images, or the first display unit and the second display unit 1312 may display a single image.

[0129] FIG. 14 is a schematic diagram illustrating an example of a lighting device using the light-emitting device 100 of this embodiment. The lighting device 1400 may include a housing 1401, a light source 1402, a circuit board 1403, an optical film 1404, and a light diffusion unit 1405. The light-emitting device 100 of this embodiment can be applied to the light source 1402. The optical film 1404 may be a filter that improves the color rendering of the light source. The light diffusion unit 1405 can effectively diffuse light from the light source, such as for lighting, and deliver the light over a wide area. If necessary, a cover may be provided on the outermost part. The lighting device 1400 may include both the optical film 1404 and the light diffusion unit 1405, or only one of them.

[0130] The lighting device 1400 is, for example, a device that illuminates a room. The lighting device 1400 may emit white, daylight white, or any other color from blue to red. It may have a dimming circuit that adjusts the light intensity. The lighting device 1400 may have a power supply circuit connected to the light emitting device 100 that functions as the light source 1402. The power supply circuit is a circuit that converts AC voltage into DC voltage. White has a color temperature of 4200K, and daylight white has a color temperature of 5000K. The lighting device 1400 may also have a color filter. The lighting device 1400 may also have a heat sink. The heat sink dissipates heat from within the device to the outside, and examples of the heat sink include metal with a high specific heat, liquid silicon, etc.

[0131] FIG. 15 is a schematic diagram of an automobile having a tail lamp, which is an example of a vehicle lamp using the light emitting device 100 of this embodiment. The automobile 1500 may have a tail lamp 1501 that is turned on when the brakes are applied, for example. The light emitting device 100 of this embodiment may be used as a headlamp as a vehicle lamp. An automobile is an example of a mobile body, and the mobile body may be a ship, a drone, an aircraft, a railroad vehicle, an industrial robot, or the like. The mobile body may have a body and a lamp provided thereon. The lamp may indicate the current location of the body.

[0132] The light emitting device 100 of this embodiment can be applied to a tail lamp 1501. The tail lamp 1501 may have a protective member that protects the light emitting device 100 functioning as the tail lamp 1501. The protective member may be made of any material as long as it has a certain degree of strength and is transparent, but may be made of polycarbonate or the like. The protective member may also be made by mixing a furandicarboxylic acid derivative, an acrylonitrile derivative, or the like with polycarbonate.

[0133] The automobile 1500 may have a body 1503 and a window 1502 attached thereto. The window may be a window for checking the front and rear of the automobile, or may be a transparent display such as a head-up display. The light-emitting device 100 of this embodiment may be used in the transparent display. In this case, the constituent materials of the electrodes and the like of the light-emitting device 100 are made of transparent materials.

[0134] 16(a) and 16(b), a further application example of the light emitting device 100 of this embodiment will be described. The light emitting device 100 can be applied to systems that can be worn as a wearable device, such as smart glasses, a head-mounted display (HMD), or smart contact lenses. An image capturing and displaying device used in such an application example has an image capturing device capable of photoelectrically converting visible light and a light emitting device capable of emitting visible light.

[0135] 16(a) illustrates glasses 1600 (smart glasses) according to one application example. An imaging device 1602 such as a CMOS sensor or a SPAD is provided on the front side of a lens 1601 of the glasses 1600. In addition, the light emitting device 100 of this embodiment is provided on the back side of the lens 1601.

[0136] The glasses 1600 further include a control device 1603. The control device 1603 functions as a power source that supplies power to the image capture device 1602 and the light emitting device 100 according to each embodiment. The control device 1603 also controls the operations of the image capture device 1602 and the light emitting device 100. The lens 1601 is formed with an optical system for focusing light onto the image capture device 1602.

[0137] FIG. 16(b) illustrates glasses 1610 (smart glasses) according to one application example. The glasses 1610 include a control device 1612, which is equipped with an imaging device corresponding to the imaging device 1602 and a light-emitting device 100. A lens 1611 includes an optical system for projecting light emitted from the imaging device in the control device 1612 and the light-emitting device 100, and an image is projected onto the lens 1611. The control device 1612 functions as a power source for supplying power to the imaging device and the light-emitting device 100 and controls the operation of the imaging device and the light-emitting device 100. The control device 1612 may also include a gaze detection unit that detects the gaze of the wearer. Infrared light may be used for gaze detection. The infrared light-emitting unit emits infrared light toward the eyeball of a user gazing at a displayed image. An imaging unit having a light-receiving element detects the emitted infrared light reflected from the eyeball, thereby obtaining an image of the eyeball. By providing a reduction means for reducing the amount of light from the infrared light emitting section to the display section in a plan view, degradation of image quality is reduced.

[0138] The gaze of the user relative to the displayed image is detected from an image of the eyeball obtained by capturing infrared light. Any known method can be used for gaze detection using the image of the eyeball. As an example, a gaze detection method based on the Purkinje image formed by reflection of irradiated light on the cornea can be used.

[0139] More specifically, gaze detection processing is performed based on the pupil-corneal reflex method, which calculates a gaze vector representing the direction (rotation angle) of the eyeball based on the pupil image and Purkinje image included in the captured image of the eyeball, thereby detecting the user's gaze.

[0140] The light emitting device 100 according to the embodiment of the present disclosure may include an imaging device having a light receiving element, and may control the display image based on user line of sight information from the imaging device.

[0141] Specifically, the light emitting device 100 determines a first field of view area where the user gazes and a second field of view area other than the first field of view area based on the line-of-sight information. The first field of view area and the second field of view area may be determined by a control device of the light emitting device 100, or may be determined by an external control device and received. In the display area of the light emitting device 100, the display resolution of the first field of view area may be controlled to be higher than the display resolution of the second field of view area. In other words, the resolution of the second field of view area may be lower than that of the first field of view area.

[0142] The display area includes a first display area and a second display area different from the first display area, and a high-priority area is determined from the first display area and the second display area based on line-of-sight information. The first display area and the second display area may be determined by a control device of the light-emitting device 100, or may be determined by an external control device and received. The resolution of the high-priority area may be controlled to be higher than the resolution of areas other than the high-priority area. In other words, the resolution of an area with a relatively low priority may be lowered.

[0143] Note that AI may be used to determine the first field of view area and areas with high priority. The AI may be a model configured to estimate the angle of gaze and the distance to an object in the line of sight from the image of the eyeball, using as training data an image of the eyeball and the direction in which the eyeball in the image was actually looking. The AI program may be included in the light-emitting device 100, the imaging device, or an external device. If included in an external device, it is transmitted to the light-emitting device 100 via communication.

[0144] When display control is performed based on visual recognition detection, the smart glasses can be applied to smart glasses that further include an imaging device for capturing images of the outside world. The smart glasses can display captured outside information in real time.

[0145] <Summary of the embodiment> [Item 1] A light emitting device, comprising: a plurality of pixel circuits each including a light emitting element that emits light of a luminance corresponding to a pixel signal; a drive circuit that selects a pixel circuit to which the pixel signal is to be written from the plurality of pixel circuits; a plurality of power supply lines for supplying a power supply voltage to the plurality of pixel circuits; the plurality of power supply lines include power supply lines extending in a first direction in portions overlapping the plurality of pixel circuits, the number of pixel circuits selected at the same timing by the drive circuit from two or more pixel circuits arranged along the first direction among the plurality of pixel circuits is two or less; a light-emitting device, wherein the number of pixel circuits selected at the same timing by the drive circuit from two or more pixel circuits among the plurality of pixel circuits arranged along a second direction perpendicular to the first direction is two or less. [Item 2] Item 1. The light-emitting device according to item 1, wherein the plurality of power supply lines further include a power supply line extending in the second direction in a portion overlapping the plurality of pixel circuits. [Item 3] the number of pixel circuits selected by the drive circuit at the same timing from two or more pixel circuits arranged along the first direction among the plurality of pixel circuits is one or less; 3. The light-emitting device according to item 1 or 2, wherein the number of pixel circuits selected at the same timing by the drive circuit from two or more pixel circuits arranged along the second direction among the plurality of pixel circuits is one or less. [Item 4] the light-emitting device further includes a plurality of scanning lines for supplying selection signals from the drive circuit to the plurality of pixel circuits; 4. The light emitting device according to any one of items 1 to 3, wherein at least any of the plurality of scanning lines includes a portion that intersects obliquely with both the first direction and the second direction. [Item 5] 5. The light emitting device according to item 4, wherein the drive circuit supplies a selection signal with a higher drive strength to a scanning line that is longer. [Item 6] the plurality of pixel circuits are arranged to form a plurality of pixel rows and a plurality of pixel columns, 6. The light emitting device according to any one of items 1 to 5, wherein each of the plurality of pixel rows or each of the plurality of pixel columns is parallel to the first direction. [Item 7] the plurality of pixel circuits are arranged to form a plurality of pixel rows and a plurality of pixel columns, 6. The light emitting device according to any one of items 1 to 5, wherein each of the plurality of pixel rows and each of the plurality of pixel columns are diagonally intersecting with the first direction. [Item 8] 8. A display device comprising: the light-emitting device according to any one of items 1 to 7; and an active element connected to the light-emitting device. [Item 9] an optical unit having a plurality of lenses, an image sensor that receives light that has passed through the optical unit, and a display unit that displays an image; 8. A photoelectric conversion device, wherein the display unit displays an image captured by the imaging element, and the photoelectric conversion device comprises the light-emitting device according to any one of items 1 to 7. [Item 10] A display unit is provided in the housing, and a communication unit is provided in the housing and communicates with an external device. 8. An electronic device, wherein the display unit comprises the light-emitting device according to any one of items 1 to 7. [Item 11] A lighting device having a light source and at least one of a light diffusion unit and an optical film, 8. A lighting device, wherein the light source comprises the light emitting device according to any one of items 1 to 7. [Item 12] A moving body having a body and a lighting fixture provided on the body, A moving body characterized in that the lighting fixture has the light-emitting device described in any one of items 1 to 7.

[0146] The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0147] 100 light emitting device, 110 driving circuit, 120 pixel circuit, 206 scanning line, 207 power line

Claims

1. A light emitting device, comprising: a plurality of pixel circuits each including a light emitting element that emits light of a luminance corresponding to a pixel signal; a drive circuit that selects a pixel circuit to which the pixel signal is to be written from the plurality of pixel circuits; a plurality of power supply lines for supplying a power supply voltage to the plurality of pixel circuits; the plurality of power supply lines include a power supply line extending in a first direction in a portion overlapping with the plurality of pixel circuits, the number of pixel circuits selected at the same timing by the drive circuit from two or more pixel circuits arranged along the first direction among the plurality of pixel circuits is two or less; a light-emitting device, wherein the number of pixel circuits selected at the same timing by the drive circuit from two or more pixel circuits among the plurality of pixel circuits arranged along a second direction perpendicular to the first direction is two or less.

2. The light emitting device according to claim 1 , wherein the plurality of power supply lines further include a power supply line extending in the second direction in a portion overlapping the plurality of pixel circuits.

3. the number of pixel circuits selected by the drive circuit at the same timing from two or more pixel circuits arranged along the first direction among the plurality of pixel circuits is one or less; 2. The light emitting device according to claim 1, wherein the number of pixel circuits selected at the same timing by the drive circuit from two or more pixel circuits arranged along the second direction among the plurality of pixel circuits is one or less.

4. the light-emitting device further includes a plurality of scanning lines for supplying selection signals from the drive circuit to the plurality of pixel circuits; The light emitting device according to claim 1 , wherein at least any of the plurality of scanning lines includes a portion that obliquely intersects both the first direction and the second direction.

5. The light emitting device according to claim 4 , wherein the driving circuit supplies a selection signal with a higher driving strength to a scanning line that is longer.

6. the plurality of pixel circuits are arranged to form a plurality of pixel rows and a plurality of pixel columns, The light emitting device according to claim 1 , wherein each of the plurality of pixel rows or each of the plurality of pixel columns is parallel to the first direction.

7. the plurality of pixel circuits are arranged to form a plurality of pixel rows and a plurality of pixel columns, The light emitting device according to claim 1 , wherein each of the plurality of pixel rows and each of the plurality of pixel columns are diagonal to the first direction.

8. A display device comprising: the light-emitting device according to claim 1; and an active element connected to the light-emitting device.

9. an optical unit having a plurality of lenses, an image sensor that receives light that has passed through the optical unit, and a display unit that displays an image; A photoelectric conversion device, wherein the display section displays an image captured by the imaging element, and the photoelectric conversion device comprises the light-emitting device according to claim 1 .

10. A display unit is provided in the housing, and a communication unit is provided in the housing and communicates with an external device.

8. An electronic device, wherein the display unit comprises the light-emitting device according to claim 1.

11. A lighting device having a light source and at least one of a light diffusion unit and an optical film, 8. An illumination device, wherein the light source comprises the light emitting device according to claim 1.

12. A moving body having a body and a lighting fixture provided on the body, A moving body, wherein the lighting fixture comprises the light emitting device according to any one of claims 1 to 7.

Images