JP2017058671A - Display unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a deterioration in image quality.SOLUTION: A display unit 10 comprises: a low density area 54 that has pixels including a plurality of sub pixels each having a self-luminous layer arranged in a two-dimensional matrix form and includes low density pixels each having a first number of sub pixels; a high density area 52 that includes high density pixels each having a second number of sub pixels, the second number being larger than the first number; and a lighting driving circuit that turns on the self-luminous layers.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a display device.

  In recent years, there has been a growing demand for display devices for mobile electronic devices such as mobile phones and electronic paper. In a display device, one pixel includes a plurality of sub-pixels, each of the plurality of sub-pixels outputs light of a different color, and the display of the sub-pixel is switched on and off, so that one pixel can perform various operations. The color is displayed. In this display device, there is a technique of adding a white pixel as a fourth subpixel to a conventional red, green, and blue subpixel (for example, Patent Document 1). This technique can improve image quality by adding white pixels.

  Further, for example, in Patent Document 1, the design cost is minimized while improving the image quality by dividing the region composed of red, green, and blue sub-pixels into the region composed of red, green, blue, and white sub-pixels. A liquid crystal display device is described.

JP 2007-94089 A

  However, an area composed of red, green, blue, and white subpixels has more wiring for driving each subpixel than an area composed of red, green, and blue subpixels. For example, in Patent Document 1, an image is displayed by irradiating light from a backlight. Therefore, the aperture ratio of the area composed of red, green, blue, and white subpixels is smaller than that of the area composed of red, green, and blue subpixels by the amount of wiring. Therefore, in this case, the brightness of the image differs from region to region, and the image quality may deteriorate. Furthermore, if the image quality deterioration is likely to proceed, the life of the display device may be shortened. In addition, a display device including four types of sub-pixels of red, green, blue, and white has a region around an image display surface on which various circuits are arranged as compared to a display device including three types of sub-pixels. It may become wide.

  In order to solve the above-described problems, the present invention provides a display device that suppresses deterioration of image quality, suppresses shortening of the lifetime of the display device, and further suppresses an increase in the area around the image display surface. For the purpose.

  The display device of the present invention includes a low-density region having low-density pixels in which pixels having a plurality of sub-pixels each having a self-light-emitting layer are arranged in a two-dimensional matrix and having a first number of the sub-pixels; A high-density region having high-density pixels having a second number of sub-pixels greater than the first number, and a lighting drive circuit for lighting the self-light-emitting layer.

FIG. 1 is a block diagram illustrating an example of the configuration of the display device according to the first embodiment. FIG. 2 is a block diagram illustrating the configuration of the scanning circuit. FIG. 3 is a diagram illustrating a lighting drive circuit for sub-pixels included in the pixels of the image display panel according to the first embodiment. FIG. 4A is a diagram illustrating an arrangement of sub-pixels of high-density pixels. FIG. 4B is a diagram illustrating an arrangement of sub-pixels of low-density pixels. FIG. 5 is an explanatory diagram schematically illustrating circuit wiring in a low density region and a high density region. FIG. 6A is a diagram schematically showing a cross-sectional structure of the image display panel in a high-density region. FIG. 6B is a diagram schematically showing a cross-sectional structure of the image display panel in the low density region. FIG. 7 is a block diagram illustrating the configuration of the signal processing unit according to the first embodiment. FIG. 8A is a conceptual diagram of a reproduction HSV color space that can be reproduced by the display device of the present embodiment. FIG. 8B is a conceptual diagram showing the relationship between hue and saturation in the reproduction HSV color space. FIG. 8C is a graph showing the relationship between saturation and expansion coefficient. FIG. 9 is a schematic diagram schematically showing the configuration of the image display panel according to the second embodiment. FIG. 10 is a schematic diagram schematically showing the configuration of the image display panel according to the third embodiment. FIG. 11 is an explanatory diagram schematically illustrating circuit wiring in the low density region and the high density region in the third embodiment. FIG. 12 is a schematic diagram schematically showing the configuration of the image display panel according to the fourth embodiment. FIG. 13 is a diagram illustrating a sub-pixel arrangement of low-density pixels according to the fourth embodiment. FIG. 14 is an explanatory diagram schematically illustrating circuit wiring in a low density region and a high density region in the fourth embodiment. FIG. 15 is a circuit diagram schematically showing the configuration of the drive control circuit according to the present embodiment. FIG. 16 is a block diagram schematically illustrating the configuration of the signal processing unit according to the fourth embodiment. FIG. 17 is a circuit diagram schematically showing a configuration of a drive control circuit according to another example of the present embodiment. FIG. 18 is a schematic diagram schematically illustrating a configuration of an image display panel according to another example of the fourth embodiment. FIG. 19 is an explanatory diagram schematically illustrating circuit wiring in a low density region and a high density region according to another example of the fourth embodiment. FIG. 20 is a diagram illustrating a sub-pixel arrangement of low density pixels according to another example of the fourth embodiment. FIG. 21A is a diagram showing a sub-pixel arrangement of high-density pixels according to the first modification. FIG. 21B is a diagram showing a sub-pixel arrangement of low density pixels according to the first modification. FIG. 22 is a block diagram illustrating a configuration of a signal processing unit according to the first modification. FIG. 23 is a schematic diagram schematically showing the configuration of the image display panel according to the first modification. FIG. 24 is an explanatory diagram for explaining an example of rendering processing. FIG. 25 is an explanatory diagram for explaining the smoothing process. FIG. 26 is a flowchart illustrating a process of generating an output signal by the signal processing unit according to the first modification. FIG. 27 is a diagram illustrating another example of the sub-pixel arrangement of the high-density pixels. FIG. 28 is a block diagram illustrating an example of a configuration of a display device according to a second modification. FIG. 29 is a diagram illustrating a sub-pixel drive circuit included in the pixel of the image display panel according to the second modification. FIG. 30A is a diagram schematically showing a cross-sectional structure of the image display panel in the high-density region in the second modified example. FIG. 30B is a diagram schematically showing a cross-sectional structure of the image display panel in the low density region in the second modification. FIG. 31 is a diagram illustrating an example of an electronic apparatus to which the display device according to the first embodiment is applied. FIG. 32 is a diagram illustrating an example of an electronic apparatus to which the display device according to the first embodiment is applied.

  Embodiments of the present invention will be described below with reference to the drawings. It should be noted that the disclosure is merely an example, and those skilled in the art can easily conceive of appropriate modifications while maintaining the gist of the invention are naturally included in the scope of the present invention. In addition, the drawings may be schematically represented with respect to the width, thickness, shape, and the like of each part in comparison with actual aspects for the sake of clarity of explanation, but are merely examples, and the interpretation of the present invention is not limited. It is not limited. In addition, in the present specification and each drawing, elements similar to those described above with reference to the previous drawings are denoted by the same reference numerals, and detailed description may be omitted as appropriate.

(First embodiment)
FIG. 1 is a block diagram illustrating an example of the configuration of the display device according to the first embodiment. As illustrated in FIG. 1, the display device 10 according to the first embodiment includes a signal processing unit 20, a signal output circuit 31, a scanning circuit 32, a power supply circuit 33, and an image display panel 40. The signal output circuit 31, the scanning circuit 32, and the power supply circuit 33 constitute an image display panel driving unit 30. The signal processing unit 20 and the image display panel driving unit 30 are incorporated in the image display panel 40. The signal processing unit 20 receives an input signal from the image output unit 12 of the control device 11 and sends a signal generated by performing predetermined data processing to the input signal to each unit of the display device 10. The image display panel driving unit 30 controls driving of the image display panel 40 based on the signal from the signal processing unit 20. The image display panel 40 is a self-luminous image display panel that displays an image by lighting a self-luminous body of a pixel based on a signal from the image display panel driving unit 30.

(Configuration of image display panel driver)
The image display panel drive unit 30 is a control device for the image display panel 40, and includes the signal output circuit 31, the scanning circuit 32, and the power supply circuit 33 as described above. The signal output circuit 31 is electrically connected to a sub-pixel 49 included in each pixel 48 in the image display panel 40 by a signal line DTL. The signal output circuit 31 holds the input image output signal and sequentially outputs it to each sub-pixel 49 of the image display panel 40. The scanning circuit 32 is electrically connected to each sub-pixel 49 of the image display panel 40 by the scanning line SCL. The scanning circuit 32 selects each sub-pixel 49 in the image display panel 40 and turns on / off a switching element (for example, a thin film transistor (TFT)) for controlling the operation (light emission intensity) of the sub-pixel 49. To control. The power supply circuit 33 supplies power for causing each sub-pixel 49 to emit light to each lighting drive circuit 45 described later via the power supply line PCL.

FIG. 2 is a block diagram illustrating the configuration of the scanning circuit. More specifically, the scanning circuit 32 includes a shift register unit 34 and a line buffer unit 35 as shown in FIG. Shift register unit 34 is a circuit for outputting a scanning signal to the scan output line SCL _X, a scanning signal output to a predetermined scanning output line SCL _X, is sequentially transferred to the scan output line SCL _X of the next row. The line buffer unit 35 is connected to the shift register unit 34 via the scanning output line SCL _X, and is connected to the sub-pixels 49 of each row via the scanning line SCL. The line buffer unit 35 amplifies the scanning signal output from the shift register unit 34 and outputs the amplified signal to the sub-pixels 49 in each row. The line buffer unit 35 includes, for example, a plurality of transistors, and each transistor is connected to the scanning output line SCL _X of each row. Scan signals sequentially output from the shift register unit 34 for each row are sequentially amplified by the transistors of the line buffer unit 35 and sequentially output to the sub-pixels 49 in each row. Thus, the scanning circuit 32 selects the sub-pixels 49 in order along the row direction (Y direction) by the shift register unit 34 and the line buffer unit 35.

(Image display panel configuration)
As shown in FIG. 1, the image display panel 40 has a rectangular shape with a short X direction (row direction) and a long Y direction (column direction). However, the shape of the image display panel 40 is not limited to this and is arbitrary. The image display panel 40 includes frame portions 41 and 42 and an image display surface 50. The frame portions 41 and 42 are portions that do not have the pixel 48 and do not display an image. The frame portions 41 and 42 may be covered with a material different from the surface of the image display panel 40, for example, or may be the same material as the surface of the image display panel 40 and shielded from light by a black matrix. The image display surface 50 is a surface on which pixels 48 are arranged to display an image. The image display surface 50 occupies the entire area of the image display panel 40 along the X direction. The image display surface 50 is adjacent to the frame portions 41 and 42 at both ends in the Y direction.

  The signal processing unit 20 and the signal output circuit 31 are incorporated inside the frame unit 42. However, at least one of the signal processing unit 20 and the signal output circuit 31 may be incorporated in the frame unit 41.

On the image display surface 50, the pixels 48 are arranged in a P ₂ × Q ₀ (P _{0 in} the row direction, Q _{0 in} the column direction) two-dimensional matrix (matrix). As shown in FIG. 1, the image display surface 50 is divided into a high density region 52 and low density regions 54A and 54B. The high density region 52 is located at the center of the image display surface 50 in the X direction. The low density regions 54 </ b> A and 54 </ b> B are located at both ends in the X direction of the high density region 52 and are adjacent to the high density region 52. Specifically, the high density region 52 is rectangular. The low density region 54A is adjacent to one side of the high density region 52 on the X direction side from one end of the one side to the other end along the Y direction. The low density region 54B is adjacent to the other side on the X direction side of the high density region 52 along the Y direction from one end of the other side to the other end. The high-density region 52 and the low-density regions 54A and 54B differ in the number of sub-pixels 49 included in the pixel 48, which will be described in detail later. Hereinafter, when the low density regions 54A and 54B are not distinguished, they are described as the low density region 54.

  FIG. 3 is a diagram illustrating a lighting drive circuit for sub-pixels included in the pixels of the image display panel according to the first embodiment. The pixel 48 includes a plurality of sub-pixels 49, and the lighting drive circuits 45 of the sub-pixels 49 shown in FIG. 3 are arranged in a two-dimensional matrix (matrix). As shown in FIG. 3, the lighting drive circuit 45 includes a control transistor Tr1, a drive transistor Tr2, and a charge holding capacitor C1. The gate of the control transistor Tr1 is connected to the scanning line SCL, the source is connected to the signal line DTL, and the drain is connected to the gate of the driving transistor Tr2. One end of the charge holding capacitor C1 is connected to the gate of the driving transistor Tr2, and the other end is connected to the source of the driving transistor Tr2. The source of the driving transistor Tr2 is connected to the power supply line PCL, and the drain of the driving transistor Tr2 is connected to the anode of the organic light emitting diode E1 that is a self-luminous body. The cathode of the organic light emitting diode E1 is connected to a reference potential (for example, ground), for example. Although FIG. 3 shows an example in which the control transistor Tr1 is an n-channel transistor and the drive transistor Tr2 is a p-channel transistor, the polarity of each transistor is not limited to this. The polarities of the control transistor Tr1 and the drive transistor Tr2 may be determined as necessary.

  Next, the arrangement of the sub-pixels 49 in the pixel 48 will be described. FIG. 4A is a diagram illustrating an arrangement of sub-pixels of high-density pixels. FIG. 4B is a diagram illustrating an arrangement of sub-pixels of low-density pixels. The high-density pixel 48 </ b> A that is the pixel 48 in the high-density region 52 has more sub-pixels 49 than the low-density pixel 48 </ b> B that is the pixel 48 in the low-density region 54. That is, the number of sub-pixels 49 included in the high-density pixel 48A (referred to as the second number) is larger than the number of sub-pixels 49 included in the low-density pixel 48B (referred to as the first number). In other words, the high density region 52 has more subpixels 49 in the same area than the low density region 54. As shown in FIG. 4A, the high-density pixel 48A includes a first subpixel 49R, a second subpixel 49G, a third subpixel 49B, and a fourth subpixel 49W. The first sub-pixel 49R displays the primary color red as the first color. The second sub-pixel 49G displays the primary color green as the second color. The third sub-pixel 49B displays the primary color blue as the third color. The fourth subpixel 49W displays white as a fourth color different from the first color, the second color, and the third color. However, the first color, the second color, the third color, and the fourth color are not limited to red, green, blue, and white, respectively, and any color such as a complementary color can be selected. The first sub-pixel 49R, the second sub-pixel 49G, the third sub-pixel 49B, and the fourth sub-pixel 49W are referred to as sub-pixels 49 when it is not necessary to distinguish them from each other.

  As shown in FIG. 4A, the high-density pixel 48A includes a first sub-pixel 49R, a second sub-pixel 49G, a third sub-pixel 49B, and a fourth sub-pixel 49W arranged in 2 rows and 2 columns. Yes. The high-density pixel 48A has a first subpixel 49R in the first column of the first row, a second subpixel 49G in the second column of the first row, and a fourth in the first column of the second row. It has a subpixel 49W, and has a third subpixel 49B in the second column of the second row. In other words, in the high-density pixel 48A, the first subpixel 49R is adjacent to the second subpixel 49G in the row direction (X direction), and is adjacent to the fourth subpixel 49W in the column direction (Y direction). The second subpixel 49G is adjacent to the third subpixel 49B in the column direction (Y direction). The fourth subpixel 49W is adjacent to the third subpixel 49B in the row direction (X direction).

  As illustrated in FIG. 4B, the low density pixel 48B includes a first subpixel 49R, a second subpixel 49G, and a third subpixel 49B. In the low-density pixel 48B, the first sub-pixel 49R, the second sub-pixel 49G, and the third sub-pixel 49B are arranged in a stripe shape along the X direction. The area of the low density pixel 48B is formed substantially the same as the area of the high density pixel 48A. Therefore, the area of each subpixel 49 included in the low density pixel 48B is larger than the area of each subpixel 49 included in the high density pixel 48A. Note that “substantially the same” refers to the same range that allows a deviation within a general tolerance range.

  The sub-pixel arrangement of the high-density pixel 48A and the low-density pixel 48B is configured as described above, but the sub-pixel arrangement of the high-density pixel 48A and the low-density pixel 48B is the number of sub-pixels 49 included in the high-density pixel 48A. However, the number is not limited to the above as long as it is larger than the number of sub-pixels 49 included in the low-density pixel 48B.

  Further, the area and shape of the high-density region 52 are arbitrary as long as the high-density region 52 has the high-density pixels 48A and does not have the low-density pixels 48B. The area and shape of the low density region 54 are arbitrary as long as the low density region 54 has the low density pixels 48B and does not have the high density pixels 48B. The number of high-density pixels 48A in the high-density region 52 and the number of low-density pixels 48B in the low-density region 54 are preferably plural, but the numbers are arbitrary. The area of the high density region 52 is preferably larger than the area of the low density region 54. In other words, the number of high density pixels 48A included in the image display panel 40 is preferably larger than the number of low density pixels 48B.

  The low density region 54 further includes a drive control circuit 60 for controlling the drive of the image display panel 40. The drive control circuit 60 in the present embodiment is a scanning circuit 32 and a power supply circuit 33. However, the drive control circuit 60 may be a circuit for controlling the operation of the lighting drive circuit 45, and may include only the scanning circuit 32, for example. For example, the drive control circuit 60 selects which lighting drive circuit 45 is to be operated, and controls the amount of power that the lighting drive circuit 45 applies to the sub-pixels 49. Hereinafter, the arrangement of the drive control circuit 60 in the low density region 54 will be described.

  FIG. 5 is an explanatory diagram schematically illustrating circuit wiring in a low density region and a high density region. As shown in FIG. 5, the image display panel 40 has a plurality of signal lines DTL arranged along the Y direction. The signal line DTL is connected to the signal output circuit 31, and an image output signal for causing the sub-pixel 49 to display a predetermined color is input from the signal output circuit 31. The signal line DTL is connected to the sub-pixels 49 arranged in the same column.

  In the image display panel 40, a plurality of scanning lines SCL (SCL1, SCL2, SCL3, SCL4,...) Are arranged along the X direction. The scanning line SCL extends from the drive control circuit 60 (scanning circuit 32) along the X direction. The drive control circuit 60 sequentially outputs a scanning signal along the Y direction to each scanning line SCL. In FIG. 5, the power supply line PCL is not shown.

  The scanning line SCL is connected to the sub-pixel 49 via the lighting drive circuit 45. Specifically, the scanning line SCL1 includes the first sub-pixel 49R, the second sub-pixel 49G, and the third sub-pixel 49B of the low-density pixel 48B arranged in the same row, and the high-density pixels 48A arranged in the same row. The sub-pixel 49R is connected to the second sub-pixel 49G. The scanning line SCL2 is connected to the fourth subpixel 49W and the third subpixel 49B of the high-density pixel 48A arranged in the same row. The scanning line SCL3 includes the first sub-pixel 49R, the second sub-pixel 49G, and the third sub-pixel 49B of the low-density pixel 48B arranged in the same row, and the first sub-pixel 49R of the high-density pixel 48A arranged in the same row. It is connected to the second subpixel 49G. The scanning line SCL4 is connected to the fourth subpixel 49W and the third subpixel 49B of the high-density pixel 48A arranged in the same row. The drive control circuit 60 outputs scanning signals in order along the Y direction to the sub-pixels 49 in each row via the lighting drive circuit 45 corresponding to each sub-pixel 49. That is, the drive control circuit 60 sequentially selects the sub-pixels 49 in each row along the Y direction.

  One lighting driving circuit 45 is provided for each sub-pixel 49. Hereinafter, the lighting driving circuit 45 of the first sub-pixel 49R is referred to as a lighting driving circuit 45R, the lighting driving circuit 45 of the second sub-pixel 49G is referred to as a lighting driving circuit 45G, and the lighting driving circuit 45 of the third sub-pixel 49B is referred to as The lighting driving circuit 45B is used, and the lighting driving circuit 45 of the fourth sub-pixel 49W is called a lighting driving circuit 45W.

  Here, each sub-pixel 49 is connected to the image display surface 50 rather than each wiring (scanning line SCL and signal line DTL) through which a signal for driving the sub-pixel 49 flows, the lighting drive circuit 45, and the drive control circuit 60. It is provided above. In other words, each wiring (scanning line SCL and signal line DTL) and lighting drive circuit 45 are provided below the image display surface 50 with respect to each sub-pixel 49. In the low density region 54, the drive control circuit 60 is provided below the image display surface 50 with respect to each sub pixel 49 of the low density pixel 48B. Hereinafter, this will be specifically described with reference to FIGS. 6A and 6B.

  FIG. 6A is a diagram schematically showing a cross-sectional structure of the image display panel in a high-density region. FIG. 6B is a diagram schematically showing a cross-sectional structure of the image display panel in the low density region. 6A is a cross-sectional view taken along a cross-section A shown in FIG. 6B is a cross-sectional view taken along a cross-section B shown in FIG. As shown in FIGS. 6A and 6B, the image display panel 40 includes a substrate 71, insulating layers 72 and 73, a reflective layer 74, a lower electrode 75, a self-light emitting layer 76 as a self-light emitting body, and an upper electrode. 77, an insulating layer 78, an insulating layer 79, a color filter 81 as a color conversion layer, a black matrix 82 as a light shielding layer, and a substrate 70. The substrate 71 is a semiconductor substrate such as silicon, a glass substrate, a resin substrate, or the like, and forms or holds the lighting drive circuit 45 described above. The insulating layer 72 is a protective film that protects the lighting drive circuit 45 and the like described above, and silicon oxide, silicon nitride, or the like can be used. The lower electrode 75 is provided in each of the first subpixel 49R, the second subpixel 49G, the third subpixel 49B, and the fourth subpixel 49W, and the anode (anode) of the organic light emitting diode E1 described above. Is a conductor. The lower electrode 75 is a translucent electrode formed of a translucent conductive material (translucent conductive oxide) such as indium tin oxide (ITO). The insulating layer 73 is called a bank and is an insulating layer that partitions the first subpixel 49R, the second subpixel 49G, the third subpixel 49B, and the fourth subpixel 49W. The reflective layer 74 is formed of a material having metallic luster that reflects light from the self-light-emitting layer 76, such as silver, aluminum, or gold.

  The upper electrode 77 is a translucent electrode formed of a translucent conductive material (translucent conductive oxide) such as indium tin oxide (ITO). In the present embodiment, ITO is given as an example of the translucent conductive material, but the present invention is not limited to this. As the light-transmitting conductive material, a conductive material having another composition such as indium zinc oxide (IZO) may be used. The upper electrode 77 becomes a cathode (cathode) of the organic light emitting diode E1. The insulating layer 78 is a sealing layer that seals the above-described upper electrode 77, and silicon oxide, silicon nitride, or the like can be used. The insulating layer 79 is a planarization layer that suppresses a step generated by the bank, and silicon oxide, silicon nitride, or the like can be used. The board | substrate 70 is a translucent board | substrate which protects the image display panel 40 whole, For example, a glass substrate can be used. 5 shows an example in which the lower electrode 75 is an anode (anode) and the upper electrode 77 is a cathode (cathode), the present invention is not limited to this. The lower electrode 75 may be a cathode and the upper electrode 77 may be an anode. In this case, the polarity of the driving transistor Tr2 electrically connected to the lower electrode 75 can be appropriately changed, and the carrier It is also possible to appropriately change the stacking order of the injection layer (hole injection layer and electron injection layer), carrier transport layer (hole transport layer and electron transport layer), and light emitting layer.

  The image display panel 40 is a color display panel, and a color filter that allows light of a color corresponding to the color of the sub-pixel 49 to pass between the sub-pixel 49 and the image observer among the light-emitting components of the self-light-emitting layer 76. 81 is arranged. The image display panel 40 can emit light of colors corresponding to red, green, blue, and white. Note that the color filter 81 may not be disposed between the fourth sub-pixel 49W corresponding to white and the image observer. In the image display panel 40, the light emission component of the self-light-emitting layer 76 does not pass through the color conversion layer such as the color filter 81, and the first subpixel 49R, the second subpixel 49G, the third subpixel 49B, and the fourth subpixel. Each color of 49W can also emit light. For example, in the image display panel 40, the fourth subpixel 49W may be provided with a transparent resin layer instead of the color filter 81 for color adjustment. In this way, the image display panel 40 can suppress the occurrence of a large step in the fourth subpixel 49W by providing the transparent resin layer.

  In the present embodiment, each sub-pixel 49 includes a lower electrode 75, a self-luminous layer 76, an upper electrode 77, and a color filter 81. The lighting drive circuit 45 is a circuit for lighting the self-light emitting layer 76 of the sub-pixel 49, and is not included in the sub-pixel 49. In addition, the area of the sub-pixel 49 refers to a region inside the black matrix 82 of the color filter 81. However, when the color filter 81 is not provided, it can be said that the area of the sub-pixel 49 is the area of the lower electrode 75.

  In the high density region 52, a first subpixel 49R, a second subpixel 49G, a third subpixel 49B, and a fourth subpixel 49W are arranged. In the high-density region 52, lighting drive circuits 45R, 45G, 45B, and 45W are provided in the insulating layer 72. The insulating layer 72 is provided with respective wirings (scanning line SCL, signal line DTL, and power supply line PCL) (not shown) through which signals for driving the sub-pixels 49 flow. The drive control circuit 60 is not provided in the high density region 52. The lighting drive circuit 45 is electrically connected to the lower electrode 75 of the corresponding subpixel 49. The lighting drive circuits 45R, 45G, 45B, and 45W and the wirings are provided below the sub-pixels 49 (more specifically, the self-light-emitting layer 76) of the high-density pixel 48A. If the lighting drive circuits 45R, 45G, 45B, 45W and the respective wirings are provided below the respective sub-pixels 49 (more specifically, the self-light-emitting layer 76) of the high-density pixel 48A, the insulating layer 72 is provided. It is not limited to being provided. FIG. 6A shows only the first subpixel 49R and the fourth subpixel 49W, but the cross sections of the other subpixels 49 have the same shape.

  In the low density region 54, the first subpixel 49R, the second subpixel 49G, and the third subpixel 49B are arranged, and the fourth subpixel 49W is not arranged. In the low-density region 54, the wirings (scanning lines SCL) (not shown) through which signals for driving the lighting drive circuits 45R, 45G, and 45B, the drive control circuit 60, and the sub-pixels 49 flow in the insulating layer 72. , A signal line DTL and a power supply line PCL) are provided. The lighting drive circuit 45 is electrically connected to the lower electrode 75 of the corresponding subpixel 49. In the present embodiment, the drive control circuit 60 is electrically connected to each lighting drive circuit 45 via wiring.

  The lighting drive circuits 45R, 45G, and 45B, each wiring, and the drive control circuit 60 are provided below each sub-pixel 49 (more specifically, the self-light-emitting layer 76) of the low-density pixel 48B. More specifically, the drive control circuit 60 is provided in the same layer as the lighting drive circuits 45R, 45G, and 45B and each wiring. However, the drive control circuit 60 may be provided in a layer different from the lighting drive circuits 45R, 45G, and 45B and each wiring. If the lighting drive circuits 45R, 45G, and 45B, the drive control circuit 60, and the wirings are provided below the sub-pixels 49 (more specifically, the self-light-emitting layer 76) of the low-density pixel 48B, the insulating layer 72 is provided. It is not restricted to being provided in. 6B shows only the first subpixel 49R, the cross sections of the other subpixels 49 have the same shape.

  Further, as described above, the area of the low density pixel 48B is the same as the area of the high density pixel 48A, but the lighting drive circuit 45W is not provided in the low density region 54. Therefore, the low-density area 54 has more space than the high-density area 52 by the amount corresponding to the lighting drive circuit 45W. The drive control circuit 60 is provided in a portion of the low density region 54 where there is a sufficient space without the lighting drive circuit 45W being disposed.

  The above is the arrangement of the drive control circuit 60. In addition, the above-mentioned self-light-emitting layer 76 includes an organic material, and includes a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer (not shown).

(Hall transport layer)
As the layer that generates holes, for example, a layer including an aromatic amine compound and a substance that exhibits an electron accepting property with respect to the compound is preferably used. Here, the aromatic amine compound is a substance having an arylamine skeleton. Among aromatic amine compounds, those containing triphenylamine in the skeleton and having a molecular weight of 400 or more are preferable. Among aromatic amine compounds having triphenylamine in the skeleton, those containing a condensed aromatic ring such as a naphthyl group in the skeleton are particularly preferable. By using an aromatic amine compound containing triphenylamine and a condensed aromatic ring in the skeleton, the heat resistance of the light-emitting element is improved. Specific examples of the aromatic amine compound include 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (abbreviation: α-NPD), 4,4′-bis [N— (3-methylphenyl) -N-phenylamino] biphenyl (abbreviation: TPD), 4,4 ′, 4 ″ -tris (N, N-diphenylamino) triphenylamine (abbreviation: TDATA), 4,4 ′ , 4 ″ -tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine (abbreviation: MTDATA), 4,4′-bis [N- {4- (N, N-di-m) -Tolylamino) phenyl} -N-phenylamino] biphenyl (abbreviation: DNTPD), 1,3,5-tris [N, N-di (m-tolyl) amino] benzene (abbreviation: m-MTDAB), 4,4 ', 4''-Tris (N-carbazoli ) Triphenylamine (abbreviation: TCTA), 2,3-bis (4-diphenylaminophenyl) quinoxaline (abbreviation: TPAQn), 2,2 ′, 3,3′-tetrakis (4-diphenylaminophenyl) -6, 6′-biskinoxaline (abbreviation: D-TriPhAQn), 2,3-bis {4- [N- (1-naphthyl) -N-phenylamino] phenyl} -dibenzo [f, h] quinoxaline (abbreviation: NPDiBzQn) Etc. There are no particular limitations on the substance that exhibits an electron accepting property with respect to the aromatic amine compound. For example, molybdenum oxide, vanadium oxide, 7,7,8,8-tetracyanoquinodimethane (abbreviation: TCNQ), 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (abbreviation: F4-TCNQ) or the like can be used.

(Electron injection layer, electron transport layer)
There is no particular limitation on the electron-transporting substance, and for example, tris (8-quinolinolato) aluminum (abbreviation: Alq ₃ ), tris (4-methyl-8-quinolinolato) aluminum (abbreviation: Almq ₃ ), bis (10-hydroxybenzo) [H] -quinolinato) beryllium (abbreviation: BeBq ₂ ), bis (2-methyl-8-quinolinolato) -4-phenylphenolato-aluminum (abbreviation: BAlq), bis [2- (2-hydroxyphenyl) benzoxa Zolato] zinc (abbreviation: Zn (BOX) ₂ ), bis [2- (2-hydroxyphenyl) benzothiazolate] zinc (abbreviation: Zn (BTZ) ₂ ) and other metal complexes, as well as 2- (4-biphenylyl) -5- (4-tert-butylphenyl) -1,3,4-oxadiazole (abbreviation: PBD), 1,3-bi [5- (p-tert-butylphenyl) -1,3,4-oxadiazol-2-yl] benzene (abbreviation: OXD-7), 3- (4-tert-butylphenyl) -4-phenyl -5- (4-biphenylyl) -1,2,4-triazole (abbreviation: TAZ), 3- (4-tert-butylphenyl) -4- (4-ethylphenyl) -5- (4-biphenylyl)- 1,2,4-triazole (abbreviation: p-EtTAZ), bathophenanthroline (abbreviation: BPhen), bathocuproine (abbreviation: BCP), or the like can be used. In addition, there is no particular limitation on a substance that exhibits an electron donating property with respect to an electron transporting substance. For example, alkaline metals such as lithium and cesium, alkaline earth metals such as magnesium and calcium, rare earth metals such as erbium and ytterbium, and the like Can be used. Further, lithium oxide (Li ₂ O), calcium oxide (CaO), sodium oxide (Na ₂ O), potassium oxide (K ₂ O), magnesium oxide (MgO), alkali metal oxides and alkalis A substance selected from earth metal oxides may be used as a substance that exhibits an electron donating property with respect to an electron transporting substance.

(Light emitting layer)
For example, to obtain red light emission, 4-dicyanomethylene-2-isopropyl-6- [2- (1,1,7,7-tetramethyljulolidin-9-yl) ethenyl] -4H-pyran ( Abbreviation: DCJTI), 4-dicyanomethylene-2-methyl-6- [2- (1,1,7,7-tetramethyljulolidin-9-yl) ethenyl] -4H-pyran (abbreviation: DCJT), 4 -Dicyanomethylene-2-tert-butyl-6- [2- (1,1,7,7-tetramethyljulolidin-9-yl) ethenyl] -4H-pyran (abbreviation: DCJTB), periflanthene, 2,5 -Dicyano-1,4-bis [2- (10-methoxy-1,1,7,7-tetramethyljulolidin-9-yl) ethenyl] benzene, etc., emission spectrum from 600 nm to 680 nm It can be used and a substance which exhibits emission with a peak. When green light emission is desired, N, N′-dimethylquinacridone (abbreviation: DMQd), coumarin 6, coumarin 545T, tris (8-quinolinolato) aluminum (abbreviation: Alq3), etc., emission spectrum from 500 nm to 550 nm A substance exhibiting light emission having the following peak can be used. When blue light emission is desired, 9,10-bis (2-naphthyl) -tert-butylanthracene (abbreviation: t-BuDNA), 9,9′-bianthryl, 9,10-diphenylanthracene (abbreviation) : DPA), 9,10-bis (2-naphthyl) anthracene (abbreviation: DNA), bis (2-methyl-8-quinolinolato) -4-phenylphenolato-gallium (abbreviation: BGaq), bis (2-methyl) A substance exhibiting light emission having a peak of an emission spectrum from 420 nm to 500 nm, such as -8-quinolinolato) -4-phenylphenolato-aluminum (abbreviation: BAlq), can be used. As described above, in addition to a substance that emits fluorescence, bis [2- (3,5-bis (trifluoromethyl) phenyl) pyridinato-N, C2 ′] iridium (III) picolinate (abbreviation: Ir (CF3ppy) ₂ (Pic)), bis [2- (4,6-difluorophenyl) pyridinato-N, C2 ′] iridium (III) acetylacetonate (abbreviation: FIr (acac)), bis [2- (4,6-difluoro Phosphorescence such as phenyl) pyridinato-N, C2 ′] iridium (III) picolinate (FIr (pic)), tris (2-phenylpyridinato-N, C2 ′) iridium (abbreviation: Ir (ppy) ₃ ), etc. The substance to be used can also be used as a luminescent substance.

(Configuration of signal processor)
Next, the configuration of the signal processing unit 20 will be described. The signal processing unit 20 processes the input signal input from the control device 11 and generates an output signal. The signal processing unit 20 displays red (first color), green (first color) input values of input signals to be displayed by combining red (first color), green (second color), and blue (third color) colors. Two color), blue (third color), and white (fourth color) are generated by being converted into reproduction values (output signals) of an enlarged color space (HSV color space in the first embodiment). Then, the signal processing unit 20 outputs the generated output signal to the image display panel driving unit 30. The enlarged color space will be described later. In the first embodiment, the enlarged color space is an HSV color space, but is not limited thereto, and may be an XYZ color space, a YUV space, or other coordinate system.

  FIG. 7 is a block diagram illustrating the configuration of the signal processing unit according to the first embodiment. As illustrated in FIG. 7, the signal processing unit 20 includes a region information acquisition unit 21 and an output signal generation unit 22. The area information acquisition unit 21 stores which pixel 48 among all the pixels 48 in the image display panel 40 is the high-density pixel 48A. The output signal generation unit 22 acquires an input signal from the control device 11, and acquires information on which pixels 48 are high-density pixels 48 </ b> A from the region information acquisition unit 21. The output signal generation unit 22 performs an expansion process on the input signal corresponding to each sub-pixel 49 of the high-density pixel 48A to generate an output signal. The output signal generation unit 22 performs normal processing (without performing expansion processing) on the input signal corresponding to each sub-pixel 49 of the low-density pixel 48B, and generates an output signal. The output signal generation process will be described later. Note that the region information acquisition unit 21 may store which pixels 48 are the low-density pixels 48B.

(Processing of display device)
Next, the processing operation by the signal processing unit 20 will be described. The signal processing unit 20 receives an input signal, which is information about an image to be displayed, from the control device 11. The input signal includes information on an image (color) displayed at the position for each pixel as an input signal. Specifically, for the (p, q) -th pixel (where 1 ≦ p ≦ I, 1 ≦ q ≦ Q _{0 )} , the first subpixel having a signal value x _{1− (p, q)} , An input signal of the second subpixel having a signal value of x _{2-(p, q)} , and a signal including an input signal of the third subpixel having a signal value of x _{3-(p, q)} . The signal is input to the signal processing unit 20. First, the signal processing unit 20 determines to perform expansion processing on the high-density pixels 48A and normal processing on the low-density pixels 48B based on the information stored in the region information acquisition unit 21.

The signal processing unit 20 processes the input signal to output the first subpixel output signal (signal value _{X1- (p, q)} ) for determining the display gradation of the first subpixel 49R, the second The output signal of the second subpixel (signal value _{X2- (p, q)} ) for determining the display gradation of the subpixel 49G, and the third subpixel for determining the display gradation of the third subpixel 49B Output signal (signal value X _{3− (p, q)} ) is generated and output to the image display panel drive unit 30. Further, the signal processing unit 20 processes the input signal to determine the output signal of the fourth subpixel (signal value X _4-(p) for determining the display gradation of the fourth subpixel 49W of the high-density pixel 48A. _{, Q)} ) are generated and output to the image display panel drive unit 30. Hereinafter, output signal generation processing (decompression processing) for the high-density pixel 48A will be specifically described.

  FIG. 8A is a conceptual diagram of a reproduction HSV color space that can be reproduced by the display device of the present embodiment. FIG. 8B is a conceptual diagram showing the relationship between hue and saturation in the reproduction HSV color space. The display device 10 includes the fourth sub-pixel 49W that outputs the fourth color (white) to the high-density pixel 48A, thereby reproducing a color space (HSV color in the first embodiment) as illustrated in FIG. 8A. The dynamic range of brightness in (space) has been expanded. That is, as shown in FIG. 8A, the enlarged color space reproduced by the display device 10 is a color space on a cylindrical color space that can be displayed by the first subpixel 49R, the second subpixel 49G, and the third subpixel 49B. The maximum value of lightness decreases as the degree increases, and the shape in the cross section including the saturation axis and the lightness axis is a shape on which a solid body having a substantially trapezoidal shape with a hypotenuse being a curve is placed. The maximum value Vmax (S) of the brightness with the saturation S in the enlarged color space (HSV color space in the first embodiment) enlarged by adding the fourth color (white) as a variable is given to the signal processing unit 20. It is remembered. That is, the signal processing unit 20 stores the value of the maximum brightness value Vmax (S) for each coordinate (value) of saturation and hue with respect to the three-dimensional shape of the enlarged color space shown in FIG. 8A. Here, since the input signal is composed of the input signals of the first sub-pixel 49R, the second sub-pixel 49G, and the third sub-pixel 49B, the color space of the input signal has a cylindrical shape, that is, an enlarged color space. It becomes the same shape as the cylindrical portion.

  First, the signal processing unit 20 obtains the saturation S and the lightness V (S) in the high-density pixel 48A by the output signal generation unit 22 based on the input signal value of the sub-pixel 49 in the high-density pixel 48A, and the expansion coefficient. α is calculated. The expansion coefficient α is set for each high-density pixel 48A.

Here, the saturation S and the lightness V (S) are represented by S = (Max−Min) / Max and V (S) = Max. The saturation S can take a value from 0 to 1, the lightness V (S) can take a value from 0 to (2 ⁿ −1), and n is the number of display gradation bits. In addition, Max is the maximum value of the input signal values of the three subpixels, that is, the input signal value of the first subpixel 49R to the pixel, the input signal value of the second subpixel 49G, and the input signal value of the third subpixel 49B. is there. Min is the minimum value of the input signal values of the three subpixels, that is, the input signal value of the first subpixel 49R to the pixel, the input signal value of the second subpixel 49G, and the input signal value of the third subpixel 49B.

In general, in the (p, q) -th pixel, the saturation (Saturation) S _{(p, q)} and the lightness (Value) V (S) _{(p, q)} of the input color in the cylindrical HSV color space are The input signal (signal value x _{1- (p, q)} ) of one subpixel, the input signal of the second subpixel (signal value x _{2− (p, q)} ), and the input signal (signal value x) of the third subpixel _{3- (p, q)} ) can be obtained from the following equations (1) and (2).

S _{(p, q)} = (Max _{(p, q)} −Min _{(p, q)} ) / Max _{(p, q)} (1)
V (S) _{(p, q)} = Max _{(p, q)} (2)

Here, Max _{(p, q)} is an input signal value of three sub-pixels 49 of (x _{1-(p, q)} , x _{2-(p, q)} , x _{3-(p, q)} ). Min _{(p, q)} is the value of three sub-pixels 49 of (x _{1-(p, q)} , x _{2-(p, q)} , x _{3-(p, q)} ). This is the minimum value of the input signal value.

  The output signal generator 22 calculates the expansion coefficient α for each of the high-density pixels 48A. The expansion coefficient α is set for each high-density pixel 48A. The output signal generation unit 22 calculates the expansion coefficient α so that the value changes according to the saturation S of the input color. More specifically, the output signal generation unit 22 calculates the expansion coefficient α so as to decrease as the saturation S of the input color increases. FIG. 8C is a graph showing the relationship between saturation and expansion coefficient. The horizontal axis of FIG. 8C is the saturation S of the input color, and the vertical axis is the expansion coefficient α. The output signal generator 22 sets the expansion coefficient α to 2 when the saturation S is zero, and decreases the expansion coefficient α as the saturation S increases, as shown by a line segment α1 in FIG. 8C. When S is 1, the expansion coefficient α is set to 1. Further, as indicated by a line segment α1 in FIG. 8C, the expansion coefficient α decreases linearly as the saturation increases. However, the output signal generation unit 22 is not limited to calculating the expansion coefficient α in accordance with the line segment α1, but may be any one that calculates the expansion coefficient α so that it decreases as the saturation S of the input color increases. . For example, the output signal generator 22 may reduce the expansion coefficient α in a quadratic curve as the saturation increases, as indicated by a line segment α2 in FIG. 8C. Further, the expansion coefficient α when the saturation S is zero is not limited to 2, and can be arbitrarily set by, for example, setting based on the luminance of the fourth sub-pixel 49W. Furthermore, the output signal generation unit 22 may set the expansion coefficient α constant regardless of the saturation of the input color.

After calculating the expansion coefficient α, the output signal generation unit 22 calculates the fourth subpixel minimum value W. In the present embodiment, the output signal generation unit 22 includes an input signal (signal value x _{1- (p, q)} ) of the first subpixel and an input signal (signal value x _{2− (p, q)} ) of the second subpixel. ) And the third subpixel input signal (signal value x _{3-(p, q)} ), the expansion coefficient α, and the correction values W _R , W _G , and W _B , the fourth sub pixel minimum value W Is calculated. Correction value _{W R, W G, W B} is a correction value for displaying the white point as a target (white). White point as the target color temperature D65, etc. are previously set based on D93, the correction value _{W R,} W G, also _{W B,} which is preset values. More specifically, the output signal generation unit 22 calculates the fourth subpixel minimum value W based on the following equation (3).

_{W = Min (W R · x} 1- (p, q), W G · x 2- (p, q), W B · x 3- (p, q)) · α ··· (3)

That is, the output signal generation unit 22, the input signal value _{x 1- (p, q)} of the first sub-pixel and the correction value _W and the product of the _R, the input signal value _{x 2-(p} of the second _{subpixel, q )} and the product of the correction value W _G, calculated and a third product of the input signal value x _{3- (p subpixels, q)} and the correction value W _B, the minimum value of the minimum value The product of the expansion coefficient α is set as the fourth subpixel minimum value W.

Next, the output signal generation unit 22 calculates the output signal value X _{4− (p, q)} of the fourth subpixel based on the value of the fourth subpixel minimum value W. Specifically, when the predetermined value β is a value represented by the following expression (4), the output signal generation unit 22 determines that the fourth subpixel minimum value W is equal to or greater than the predetermined value β. The pixel output signal value X _{4- (p, q)} is calculated based on the equation (5A).

_{β = Min (W R, W} G ·, W B) · χ ··· (4)
X _{4− (p, q)} = 2 ⁿ −1 (5A)

Here, χ is a constant depending on the display device 10. No color filter is arranged in the fourth sub-pixel 49W that displays white. The fourth sub-pixel 49W that displays the fourth color, when irradiated with the same light source lighting amount, the first sub-pixel 49R that displays the first color, the second sub-pixel 49G that displays the second color, and the third color Is brighter than the third sub-pixel 49B. A signal having a value corresponding to the maximum signal value of the output signal of the first subpixel 49R is input to the first subpixel 49R, and the signal value corresponding to the maximum signal value of the output signal of the second subpixel 49G is input to the second subpixel 49G. When a signal having a value is input and a signal having a value corresponding to the maximum signal value of the output signal of the third subpixel 49B is input to the third subpixel 49B, the pixel 48 or the group of pixels 48 includes The luminance of the aggregate of the first sub-pixel 49R, the second sub-pixel 49G, and the third sub-pixel 49B is BN _1-3 . The luminance of the fourth subpixel 49W when a signal having a value corresponding to the maximum signal value of the output signal of the fourth subpixel 49W is input to the fourth subpixel 49W included in the pixel 48 or the group of pixels 48. the assume when the BN _4. That is, the maximum luminance white is displayed by the aggregate of the first sub-pixel 49R, the second sub-pixel 49G, and the third sub-pixel 49B, and this white luminance is represented by BN _1-3 . Then, when χ is a constant depending on the display device 10, the constant χ is represented by χ = BN ₄ / BN _1-3 .

Specifically, a signal value x _{1− (p, q) is} input to an aggregate of the first subpixel 49R, the second subpixel 49G, and the third subpixel 49B as an input signal having the next display gradation value. = 255, signal value x _{2− (p, q)} = 255, signal value x _{3− (p, q)} = 255, the fourth subpixel 49W for the white luminance BN _1-3 when the signal value x _{3− (p, q)} = 255 is input. For example, the luminance BN ₄ when the input signal having the display gradation value 255 is input is 1.5 times. That is, in the first embodiment, χ = 1.5.

  In the first embodiment, n = 8. That is, the number of display gradation bits is 8 bits (the display gradation value is 256 gradations from 0 to 255).

As shown in the above equation (4), the predetermined value beta, the correction value W _R, W _G, the minimum value and the product of the χ of the W _B. As shown in the above equation (5A), when the fourth subpixel minimum value W is equal to or larger than the predetermined value β, the output signal generation unit 22 outputs the output signal value X _{4- (p, q)} is the maximum gradation value (255 in this embodiment).

When the fourth subpixel minimum value W is smaller than the predetermined value β, the output signal generation unit 22 calculates the output signal value X _{4- (p, q)} of the fourth subpixel based on the following equation (5B). calculate.

X _{4- (p, q)} = W / χ (5B)

As described above, the output signal generation unit 22 calculates the output signal value X _{4- (p, q)} of the fourth subpixel. After calculating the output signal value X _{4- (p, q)} of the fourth subpixel, the output signal generation unit 22 outputs at least the input signal (signal value x _{1- (p, q)} ) of the first subpixel and itself. The output signal (signal value X _{1- (p, q)} ) of the first sub-pixel is calculated based on the expansion coefficient α of the high-density pixel 48A. The output signal generation unit 22 outputs the output signal of the second subpixel based on at least the input signal (signal value x _{2− (p, q)} ) of the second subpixel and the expansion coefficient α of the high-density pixel 48A. (Signal value _{X2- (p, q)} ) is calculated. The output signal generation unit 22 outputs the output signal of the third subpixel based on at least the input signal (signal value x _{3− (p, q)} ) of the third subpixel and the expansion coefficient α of the high-density pixel 48A. (Signal value _{X3- (p, q)} ) is calculated.

Specifically, when the fourth subpixel minimum value W is a value equal to or greater than the predetermined value β, the output signal generation unit 22 determines the first subpixel based on the following equations (6A), (7A), and (8A). The pixel output signal value _{X1- (p, q)} , the second subpixel output signal value _{X2- (p, q),} and the third subpixel output signal value _{X3- (p, q)} are calculated. .

X _{1− (p, q)} = (α · x _{1− (p, q)} · W _R −β) / W _R (6A)
_{X 2- (p, q) =} (α · x 2- (p, q) · W G -β) / W G ··· (7A)
_{X 3- (p, q) =} (α · x 3- (p, q) · W B -β) / W B ··· (8A)

When the fourth subpixel minimum value W is smaller than the predetermined value β, the output signal generation unit 22 outputs the first subpixel based on the following equations (6B), (7B), and (8B). signal value _{X 1- (p, q),} the output signal value _{X 2- (p, q)} of the second sub-pixel and the third output signal value _{X 3- (p, q)} of the subpixel is calculated.

X _{1− (p, q)} = (α · x _{1− (p, q)} · W _R −W) / W _R (6B)
_{X 2- (p, q) =} (α · x 2- (p, q) · W G -W) / W G ··· (7B)
_{X 3- (p, q) =} (α · x 3- (p, q) · W B -W) / W B ··· (8B)

As described above, the signal processing unit 20 generates an output signal of each sub-pixel 49 of the high-density pixel 48A by the expansion processing described above. Next, signal values _{X1- (p, q)} , _{X2- (p, q)} , _{X3- (p, q)} , X _, which are output signals in the (p, q) -th high-density pixel 48A. A summary of how to obtain _{4- (p, q)} (extension processing) will be described. The next processing is the luminance of the first primary color displayed by (first subpixel 49R + fourth subpixel 49W), the luminance of the second primary color displayed by (second subpixel 49G + fourth subpixel 49W), ( This is performed so as to maintain the luminance ratio of the third primary color displayed by the third subpixel 49B + the fourth subpixel 49W). In addition, the color tone is maintained (maintained). Furthermore, the gradation-luminance characteristics (gamma characteristics, γ characteristics) are maintained (maintained). Further, when any of the input signal values is zero or small in any one of the pixels 48 or the group of pixels 48, the expansion coefficient α may be obtained without including such a pixel 48 or the group of pixels 48. .

(First step)
First, the signal processing unit 20 obtains the saturation S and the brightness V in the plurality of high-density pixels 48A based on the input signal values of the sub-pixels 49 in the plurality of high-density pixels 48A, and expands each high-density pixel 48A. The coefficient α is calculated.

(Second step)
Next, the signal processing unit 20 calculates the fourth subpixel minimum value W based on the above equation (3).

(Third step)
The signal processing unit 20 calculates an output signal value X _{4- (p, q)} of the fourth subpixel based on the value of the fourth subpixel minimum value W. Specifically, when the fourth subpixel minimum value W is a value equal to or greater than the predetermined value β, the signal processing unit 20 calculates the output signal value X _{4− (p, q)} as shown in Expression (5A). The maximum gradation value (here, 255) is assumed. Further, when the fourth subpixel minimum value W is smaller than the predetermined value β, the signal processing unit 20 converts the output signal value X _{4− (p, q)} to W / χ, as shown in Expression (5B). And

(4th process)
Thereafter, when the fourth subpixel minimum value W is a value equal to or greater than the predetermined value β, the signal processing unit 20 outputs the output signal value X of the first subpixel based on the equations (6A), (7A), and (8A). _{1- (p, q),} the output signal value _{X 2- (p, q)} of the second sub-pixel and the third output signal value _{X 3- (p, q)} of the subpixel is calculated. Further, when the fourth subpixel minimum value W is smaller than the predetermined value β, the signal processing unit 20 outputs the output signal value X of the first subpixel based on the equations (6B), (7B), and (8B). _{1- (p, q),} the output signal value _{X 2- (p, q)} of the second sub-pixel and the third output signal value _{X 3- (p, q)} of the subpixel is calculated.

  The signal processing unit 20 performs the expansion process through the above steps, and generates an output signal of each sub-pixel 49 of the high-density pixel 48A.

Next, generation of an output signal of the low density pixel 48B by normal processing will be described. In the normal processing, the input signal values of the first sub-pixel 49R, the second sub-pixel 49G, and the third sub-pixel 49B of the low-density pixel 48B are directly used as the first sub-pixel 49R, the second sub-pixel 49G, and the third sub-pixel 49B. It is the process which makes it an output signal value. That is, in the normal processing, the value of the output signal value X _{1- (p, q)} of the first sub-pixel 49R remains the value of the input signal value x _{1- (p, q)} of the first sub-pixel 49R. , the value of the output signal value of the second sub-pixel 49G _{X 2- (p, q)} remains the second value of the input signal value _x of the sub-pixel 49G _{2- (p, q),} third subpixel The value of the output signal value X _{3- (p, q)} of 49B remains the value of the input signal value x _{3- (p, q)} of the third subpixel 49B.

  As described above, in the display device 10 according to the first embodiment, the pixels 48 having a plurality of sub-pixels 49 each having the self-luminous layer 76 are arranged in a two-dimensional matrix. That is, the display device 10 is a self-luminous display device. The display device 10 includes a low-density region 54 having low-density pixels 48B, a high-density region 52 having high-density pixels 48A, and a lighting drive circuit 45 that lights the self-light-emitting layer 76. The high-density pixel 48A has more subpixels 49 than the low-density pixel 48B.

  The high density pixel 48A has more subpixels 49 than the low density pixel 48B. Therefore, the number of wirings in the high density region 52 is larger than that in the low density region 54. On the other hand, since the display device 10 is a self-luminous display, the sub-pixel itself emits light without irradiating light from the back surface, thereby displaying an image. Therefore, in the display device 10, since light is not blocked by the wiring, a decrease in the aperture ratio of the high-density region 52 can be suppressed, and the difference in aperture ratio between the high-density region 52 and the low-density region 54 can be reduced. . More specifically, the aperture ratio here can be said to be the aperture area of one sub-pixel 48. Therefore, for example, in the case of a backlight type liquid crystal display device, the sub-pixel 49 in the high-density pixel 48A having a large number of wirings has a larger area blocked by the wiring, and is smaller than the sub-pixel 49 in the low-density pixel 48B. The opening area is reduced. Further, as described above, the area of the sub-pixel 49 in the high-density pixel 48A is smaller than the area of the sub-pixel 49 in the low-density pixel 48B. Therefore, the difference in opening area between the sub-pixels 49 in the high-density pixel 48A and the low-density pixel 48B may be further increased. However, in this display device 10, since light is not blocked by the wiring, it is possible to suppress an increase in the difference in opening area (opening ratio) between the sub-pixels 49 of the high-density pixel 48A and the low-density pixel 48B having a large number of wirings. can do. Therefore, the display device 10 suppresses that the brightness of the image is different for each region, and suppresses deterioration in image quality. In addition, since the display device 10 is a self-luminous display, it is possible to suppress shortening of the life as the image quality is suppressed. Further, since the display device 10 includes the low density pixels 48B, the number of wirings is reduced and the area around the image display surface is widened as compared with the display device 10 in which all the pixels 48 are the high density pixels 48A. This can be suppressed.

  Further, the sub-pixel 49 receives signals for driving the sub-pixel 49 via wiring (scanning line SCL, signal line DTL, and power supply line PCL). The wiring is provided below the self-luminous layer 76 with respect to the image display surface 50. Accordingly, in the display device 10, the light traveling outward from the self-luminous layer 76 does not travel to the wiring. Therefore, the display device 10 more preferably suppresses light from being blocked by the wiring, and more preferably suppresses deterioration of image quality.

  The low density region 54 is provided with a drive control circuit 60 for controlling the driving of the lighting drive circuit 45. In the high density region 52, the drive control circuit 60 is not provided. The low density pixel 48B has fewer subpixels 49 than the high density pixel 48A. Therefore, the low-density region 54 has fewer wirings for driving the sub-pixels 49, lighting driving circuits, and the like than the high-density region 52. In other words, the low density region 54 has more space than the high density region 52. In the display device 10 according to the present embodiment, the drive control circuit 60 that could not be disposed on the conventional image display surface 50 is disposed in the low-density region 54 where image display is possible. Therefore, the display device 10 according to the present embodiment can increase the proportion of the image display surface 50 in the image display panel 40, and can relatively enlarge the image display surface 50.

  The drive control circuit 60 is provided below the light emitting layer 76 with respect to the image display surface 50. Therefore, the display device 10 can suppress the light from being blocked by the drive control circuit 60, and can relatively enlarge the image display surface 50 while suppressing the deterioration of the image quality. In the present embodiment, the drive control circuit 60 includes the scanning circuit 32 that sequentially selects the sub-pixels 49 in order to turn on the light-emitting layer 76. In this display device, since the scanning circuit 32 can be arranged in the low density region 54, the image display surface 50 can be relatively enlarged. In the present embodiment, the drive control circuit 60 is the scanning circuit 32 and the power supply circuit 33. However, the drive control circuit 60 is a circuit different from the lighting drive circuit 45 and drives the image display panel 40. Anything can be selected as long as it is controlled.

  The high density region 52 is provided in the center of the image display surface 50, and the low density region 54 is provided in the image display surface 50 at both ends of the high density region 52. Since the low density region 54 is provided at both ends of the high density region 52, the display device 10 is provided in the high density region 52 and the low density region 54 by the drive control circuit 60 provided in the low density region 54. The subpixel 49 can be appropriately controlled. The position of the low density region 54 is not limited to this and is arbitrary. For example, the low density region 54 may be provided only at one end of the high density region 52. That is, the low density region 54 is, for example, only the low density region 54A and does not need to have the low density region 54B.

  The image display surface 50 occupies the entire area of the image display panel 40 along the X direction (predetermined direction). That is, the image display panel 40 has image display surfaces 50 at both ends in the X direction, and does not have a frame portion that does not display an image at both ends in the X direction. The image display surface 50 suppresses recognition of image boundaries in the X direction in a tiled display that displays a single image by arranging a plurality of image display panels 40, for example. Can be improved. In this embodiment, the X direction is the row direction and the Y direction is the column direction. However, the X direction and the Y direction may be arbitrary directions, for example, the X direction is the column direction and the Y direction is the row direction. It may be.

(Second Embodiment)
Next, a second embodiment will be described. The display device 10a according to the second embodiment is different from the first embodiment in that the image display surface does not occupy the entire area of the image display panel 40 in the X direction. A description of portions of the second embodiment common to the first embodiment will be omitted.

  FIG. 9 is a schematic diagram schematically showing the configuration of the image display panel according to the second embodiment. As shown in FIG. 9, the image display panel 40a included in the display device 10a includes an image display surface 50a and frame portions 43A and 43B. The image display surface 50a is located in the center of the image display panel 40a in the X direction, and the frame portions 43A and 43B are provided adjacent to both ends of the image display surface 50a in the X direction. Similar to the first embodiment, the image display surface 50a includes a high-density region 52a and low-density regions 54Aa and 54Ba.

  The frame portions 43A and 43B are portions that do not have the pixels 48 and do not display an image. The frame portions 43A and 43B may be covered with, for example, a material different from the surface of the image display panel 40, or may be the same material as the surface of the image display panel 40 and shielded from light by a black matrix. A scanning circuit 32a and a power supply circuit 33 are incorporated in the frame portions 43A and 43B. Here, the scanning circuit 32a is a circuit obtained by removing the line buffer unit 35 from the scanning circuit 32 according to the first embodiment. That is, the scanning circuit 32 a includes the shift register unit 34.

  The low density region 54 a includes a line buffer unit 35 as the drive control circuit 60. The arrangement of the line buffer unit 35 as the drive control circuit 60 is the same as that of the first embodiment, and is provided below the sub-pixels 49 (more specifically, the self-luminous layer 76) of the low-density pixel 48B. Note that the low density region 54 a may have any circuit other than the line buffer unit 35 as long as it controls the driving of the image display panel 40.

  As described above in the second embodiment, the image display surface 50a may not occupy the entire area of the image display panel 40 in the X direction. The low density region 54a (low density regions 54Aa, 54Ba) may be any circuit as long as it controls the drive of the image display panel 40, for example, has a line buffer unit 35 that is a part of the scanning circuit 32. You may have.

(Third embodiment)
Next, a third embodiment will be described. The display device 10b according to the third embodiment is different from the second embodiment in that the position of the low density region and a circuit are not provided in the low density region. Description of the third embodiment common to the second embodiment is omitted.

  FIG. 10 is a schematic diagram schematically showing the configuration of the image display panel according to the third embodiment. As shown in FIG. 10, the image display panel 40b included in the display device 10b includes an image display surface 50b and frame portions 43Ab and 43Bb. The image display surface 50b is located in the center of the image display panel 40b in the X direction, and the frame portions 43Ab and 43Bb are provided adjacent to both ends of the image display surface 50b in the X direction.

  A scanning circuit 32 and a power supply circuit 33 are incorporated in the frame portions 43Ab and 43Bb. That is, unlike the second embodiment, the frame portions 43Ab and 43Bb according to the third embodiment also have a line buffer unit 35.

  The image display surface 50b is divided into a high density region 52b and low density regions 54Ab and 54Bb. The high density region 52b is located at the center of the image display surface 50 in the X direction and the Y direction. The low density regions 54Ab and 54Bb are located at both ends in the Y direction of the high density region 52b and are adjacent to the high density region 52b. Specifically, the high density region 52b is rectangular. The low density region 54Ab is adjacent to one side on the Y direction side of the high density region 52b along the X direction from one end of the one side to the other end. The low density region 54Bb is adjacent to the other side on the Y direction side of the high density region 52 along the X direction from one end of the other side to the other end. Unlike the second embodiment, the low density region 54b (low density regions 54Ab and 54Bb) does not have the drive control circuit 60.

  FIG. 11 is an explanatory diagram schematically illustrating circuit wiring in the low density region and the high density region in the third embodiment. As illustrated in FIG. 11, the low density region 54 b includes wirings (signal lines DTL, scanning lines SCL) and low density pixels 48 </ b> B. The drive control circuit 60 is not disposed in the low density region 54b. The high-density region 52b includes each wiring (signal line DTL, scanning line SCL) and high-density pixels 48A.

  Thus, the low density region 54b may not have the drive control circuit 60 as long as it has the low density pixels 48B. Even in such a case, since the display device 10b does not block light by the wiring, it is possible to suppress a decrease in the aperture ratio of the high-density region 52b and to suppress deterioration in image quality. The display device 10b is preferably applied to, for example, a smartphone. For example, in a smartphone, a low-density area 54b on the image display surface 50b displays a time bar and a status bar indicating battery consumption. These displays generally display a fixed pattern or icon for a long time. Therefore, in the low density region 54b where such a fixed display is performed, the deterioration of the pixel is likely to proceed due to the fact that a constant current continues to flow, and the lifetime of the pixel may be shortened. Here, the low-density pixel 48B having a high aperture ratio can suppress the current consumption during driving when irradiating with the same luminance as that of the pixel having a low aperture ratio. Therefore, the low-density pixel 48B having a high aperture ratio can reduce current consumption and have a long life. In the display device 10b, the low-density pixel 48B having a long lifetime is applied to the low-density region 54b where the lifetime of the pixel is shortened. Therefore, the display device 10b can suppress a decrease in the lifetime.

  In the present embodiment, the low density regions 54b are located at both ends in the Y direction, but may also be arranged at both ends in the X direction. In this case, the drive control circuit 60 is installed in the low density regions 54b arranged at both ends in the X direction, as in the first embodiment. According to such a configuration, the low density regions 54b positioned at both ends in the Y direction suppress the decrease in life as described above, and the relative density is reduced by the low density regions 54b disposed at both ends in the X direction. In addition, it is possible to enlarge the image display surface 50 (suppress suppression of the area around the image display surface).

(Fourth embodiment)
Next, a fourth embodiment will be described. The display device 10c according to the fourth embodiment is different from the third embodiment in that a low-density region is disposed and a sensor is disposed in the low-density region. Description of the fourth embodiment common to the third embodiment is omitted.

  FIG. 12 is a schematic diagram schematically showing the configuration of the image display panel according to the fourth embodiment. As shown in FIG. 12, the image display panel 40c included in the display device 10c includes frame portions 41, 42, 43Ab, 43Bb, and an image display surface 50c. The arrangement of the image display surface 50c is the same as that of the image display surface 50b of the third embodiment.

  As shown in FIG. 12, the image display panel 40c has a high density region 52c and a low density region 54c. The low density region 54c is disposed in the high density region 52c. More specifically, the high-density region 52c is disposed over the entire area of the image display surface 50c and is adjacent to the frame portions 41, 42, 43Ab, and 43Bb. A plurality of low density regions 54c are provided at a predetermined distance in the high density region 52c, and are scattered in the high density region 52c. However, as long as the low density region 54c is disposed in the high density region 52c, the shape, area, and number of the regions are arbitrary.

  FIG. 13 is a diagram illustrating a sub-pixel arrangement of low-density pixels according to the fourth embodiment. The low density pixel 48Bc included in the low density region 54c is different from the third embodiment in the arrangement of the sub-pixels 49. As shown in FIG. 13, in the low density pixel 48Bc according to the fourth embodiment, the first sub-pixel 49R and the third sub-pixel 49B are arranged adjacent to each other in the first row. In the low density pixel 48Bc, the second sub-pixel 49G is arranged in the second row. The second subpixel 49G has a larger area than the first subpixel 49R and the third subpixel 49B, and is adjacent to the first subpixel 49R and the third subpixel 49B in the column direction (Y direction). The arrangement of the sub-pixels 49 of the low-density pixel 48Bc is not limited to this arrangement and is arbitrary. For example, the low density pixels 48Bc may have the same subpixel arrangement as the low density pixels 48B according to the first embodiment.

  Each of the low density regions 54c has a drive control circuit 60c. FIG. 14 is an explanatory diagram schematically illustrating circuit wiring in a low density region and a high density region in the fourth embodiment. FIG. 14 shows an example in which the low density region 54c has one low density pixel 48Bc. As shown in FIG. 14, the high-density region 52c includes each wiring (signal line DTL, scanning line SCL) and high-density pixels 48A. The low density region 54c includes a low density pixel 48Bc and a drive control circuit 60c. The drive control circuit 60c includes wirings SL1 and SL2 and a sensor 62. The drive control circuit 60c (wirings SL1 and SL2 and the sensor 62) is arranged in the same manner as the drive control circuit 60 according to the first embodiment, and each sub-pixel 49 (more specifically, a self-luminous layer) of the low-density pixel 48Bc. 76).

  FIG. 15 is a circuit diagram schematically showing the configuration of the drive control circuit according to the present embodiment. The drive control circuit 60 c is a circuit that detects deterioration of the self-light-emitting layer 76 of the surrounding sub-pixel 49 by the sensor 62. As shown in FIG. 15, in the present embodiment, the sensor 62 is a photodiode that detects light emission of the organic light emitting diode E <b> 1 of the sub-pixel 49. The sensor 62 generates a current having a magnitude corresponding to the light emission amount of the light emitting diode E1. The wiring SL1 is connected to the sensor information acquisition unit 24 included in the signal processing unit 20c. The wiring SL2 switches on and off a switch provided in the wiring SL1. In FIG. 14, the wiring SL1 is provided along the signal line DTL, and the wiring SL2 is provided along the scanning line SCL. However, the wirings SL1 and SL2 are arbitrarily arranged.

  The current from the sensor 62 is output to the sensor information acquisition unit 24 via the wiring SL1. The signal processing unit 20 c calculates the degree of deterioration of the organic light emitting diode E <b> 1 of the sub-pixel 49 around the sensor 62 based on the amount of current from the sensor 62 input to the sensor information acquisition unit 24. From the calculation result of the degree of degradation of the organic light emitting diode E1, the signal processing unit 20c performs a correction process such as increasing the signal value of the output signal to generate an output signal. Hereinafter, this process will be specifically described.

  FIG. 16 is a block diagram schematically illustrating the configuration of the signal processing unit according to the fourth embodiment. As illustrated in FIG. 16, the signal processing unit 20 c includes an output signal generation unit 22 c, a sensor information acquisition unit 24, and a sensor information analysis unit 25. The sensor information acquisition unit 24 acquires a current having a magnitude corresponding to the light emission amount of the light emitting diode E <b> 1 from the sensor 62. The sensor information analysis unit 25 analyzes the current value acquired by the sensor information acquisition unit 24 and calculates the degree of deterioration of the organic light emitting diode E1 of the sub-pixel 49 around the sensor 62. For example, the sensor information analysis unit 25 calculates the integrated value of the current value, and calculates the degree of deterioration of the organic light emitting diode E1 from the integrated value. The output signal generation unit 22c acquires information on the degree of deterioration of the organic light emitting diode E1 from the sensor information analysis unit 25. The output signal generation unit 22c performs a correction process on the output signal based on the information on the degree of deterioration of the organic light emitting diode E1, and outputs the output signal to the image display panel drive unit 30. For example, the output signal generation unit 22c performs a correction process for increasing the output signal in accordance with the degree of deterioration of the organic light emitting diode E1. Thereby, the display apparatus 10c can suppress the image sticking phenomenon caused by the deterioration of the organic light emitting diode E1, for example, and can suppress the deterioration of the image quality.

  As described above, in the display device 10c according to the fourth embodiment, the low density regions 54c are provided in the high density region 52 in a dotted manner. The drive control circuit 60c in the low density region 54c includes a sensor 62 that detects deterioration of the organic light emitting diode E1 of the surrounding subpixel 49. By detecting the degree of deterioration of the organic light emitting diode E1 by the sensor 62, the display device 10c can suppress, for example, a burn-in phenomenon caused by the deterioration of the organic light emitting diode E1, and can suppress deterioration in image quality.

  The drive control circuit 60c is not limited to the configuration described above as long as it detects the degree of deterioration of the organic light emitting diode E1, and may be configured as shown in FIG. 17, for example. FIG. 17 is a circuit diagram schematically showing a configuration of a drive control circuit according to another example of the present embodiment. As shown in FIG. 17, the drive control circuit 60c according to another example of the present embodiment detects a voltage input to the organic light emitting diode E1, and detects the degree of deterioration of the organic light emitting diode E1 based on the voltage value. Is. As shown in FIG. 17, the sensor 62 is a transistor, and the source is connected to the drain of the driving transistor Tr2. The drain of the sensor 62 is connected to the wiring SL1. The gate of the sensor 62 is connected to the wiring SL2. The sensor 62 amplifies the voltage output from the driving transistor Tr2 to the organic light emitting diode E1, and outputs the amplified voltage to the sensor information acquisition unit 24 via the wiring SL1. The sensor information analysis unit 25 calculates an integrated value of the voltage value, and calculates a deterioration degree of the organic light emitting diode E1 from the integrated value.

  The drive control circuit 60c may not include the sensor 62 that detects the deterioration of the organic light emitting diode E1 as long as the drive control circuit 60c includes a sensor for controlling the driving of the image display panel. The drive control circuit 60c may be, for example, a touch detection sensor or an object proximity detection sensor instead of the sensor 62. In this case, the display device 10c is a so-called in-cell type (a touch detection device is incorporated). It becomes a device. In addition, the drive control circuit 60c may include a sensor that detects external light intensity, for example. In this case, the signal value of the output signal can be corrected based on the detected external light intensity. For example, the display device 10c increases the output signal by a predetermined value when the external light intensity is greater than or equal to a predetermined value, and further increases the rate of increase of the output signal as the external light intensity increases from the predetermined value. Further, the drive control circuit 60 c may have a pixel memory that temporarily stores an image output signal of the sub-pixel 49 instead of the sensor 62. In this case, the display device 10c can reduce power consumption for displaying a still image by the pixel memory.

  In the display device 10c according to the fourth embodiment, a plurality of low density regions 54c are provided at a predetermined distance in the high density region 52c, and are scattered in the high density region 52c. However, the arrangement of the low density region 54c is arbitrary as long as it is arranged in the high density region 52c. FIG. 18 is a schematic diagram schematically illustrating a configuration of an image display panel according to another example of the fourth embodiment. As shown in FIG. 18, in the low density region 54c, a plurality of belt-like regions 55c extending along the X direction are arranged in the Y direction, and a plurality of belt-like regions 56c extending along the Y direction are arranged in the X direction. The extended region may be a region where the region 55c and the region 56c intersect each other.

  In the fourth embodiment, the sensor 62 is provided below each of the sub-pixels 49 (more specifically, the self-luminous layer 76) of the low-density pixel 48Bc. For example, the sensor 62 includes the low-density pixel 48Bc. May be provided on the same layer as or above each of the sub-pixels 49. FIG. 19 is an explanatory diagram schematically illustrating circuit wiring in a low density region and a high density region according to another example of the fourth embodiment. As shown in FIG. 19, in this example, the sensor 62 is provided in the same layer as each sub-pixel 49 of the low-density pixel 48Bc, but the other positional relationships are the same as in FIG.

  When the sensor 62 is provided in the same layer as each sub pixel 49 of the low density pixel 48Bc, the sub pixel arrangement of the low density pixel 48Bc is different from that shown in FIG. FIG. 20 is a diagram illustrating a sub-pixel arrangement of low density pixels according to another example of the fourth embodiment. FIG. 20 shows a sub-pixel arrangement of the low-density pixel 48Bc when the sensor 62 is provided in the same layer as each sub-pixel 49 of the low-density pixel 48Bc. As shown in FIG. 20, in this case, in the low density pixel 48Bc, the first sub-pixel 49R and the third sub-pixel 49B are arranged adjacent to each other in the first row. In the low density pixel 48Bc, the second sub-pixel 49G is arranged in the second row. The second subpixel 49G has substantially the same area as the first subpixel 49R and the third subpixel 49B, and is adjacent to the first subpixel 49R in the column direction (Y direction). The second subpixel 49G is not adjacent to the third subpixel 49B. The sensor 62 is provided adjacent to the second subpixel 49G in the X direction. The sensor 62 is provided adjacent to the third sub-pixel 49B in the Y direction. However, the sub-pixel arrangement of the low-density pixel 48Bc in the case where the sensor 62 is provided in the same layer as the sub-pixels 49 of the low-density pixel 48Bc is not limited to this example and is arbitrary.

  In the case where the sensor 62 is provided below the sub-pixels 49 of the low-density pixel 48Bc, the sensor 62 is, for example, a sensor that detects deterioration of the organic light emitting diode E1 shown in FIGS. Preferably there is. Further, instead of the sensor 62, for example, a pixel memory may be provided. That is, when the sensor 62 is provided below the sub-pixels 49 of the low-density pixel 48Bc, it is preferable that the sensor 62 does not affect the function even if the sensor 62 is covered with a non-transparent member. .

  In the case where the sensor 62 is provided in the same layer as the sub-pixels 49 of the low-density pixel 48Bc, the sensor 62 is preferably a touch detection sensor, an object proximity detection sensor, or an external light intensity detection sensor. That is, when the sensor 62 is in the same layer as the sub-pixels 49 of the low-density pixel 48Bc, the sensor 62 is exposed to the outside (the upper portion is not covered with a non-transparent member such as an electrode; Therefore, these sensors 62 can appropriately detect the input from the outside.

(First modification)
Next, a first modification of the first embodiment will be described. The display device 10d according to the first modification is different from the first embodiment in the arrangement of sub-pixels of low-density pixels. Description of portions common to the first embodiment of the first modification is omitted.

  FIG. 21A is a diagram showing a sub-pixel arrangement of high-density pixels according to the first modification. As shown in FIG. 21A, the sub-pixel arrangement of the high-density pixel 48A according to the first modification is the same as that of the first embodiment (see FIG. 4A). For the following description, a group of four high-density pixels 48A in which high-density pixels 48A are arranged in 2 rows and 2 columns is referred to as a high-density pixel group 47A.

  FIG. 21B is a diagram showing a sub-pixel arrangement of low density pixels according to the first modification. As shown in FIG. 21B, in the low density region 54d according to the first modification, a low density pixel group 47Bd in which low density pixels 48B1d and low density pixels 48B2d are arranged in two rows and two columns is arranged in a two-dimensional matrix. doing. The low density pixel group 47Bd has low density pixels 48B1d in the first column of the first row, low density pixels 48B2d in the second column of the first row, and low density pixels in the first column of the second row. 48B2d, and low density pixels 48B1d in the second column of the second row.

  In the low density pixel 48B1d, the first sub-pixel 49R and the second sub-pixel 49G are arranged in a stripe shape along the X direction. In the low-density pixel 48B2d, the third sub-pixel 49B and the second sub-pixel 49G are arranged in a stripe shape along the X direction. In the first modified example, the number of sub-pixels included in the low-density pixel is smaller than that in the first embodiment. Therefore, the area of each sub-pixel 49 of the low-density pixel in the first modified example is low according to the first embodiment. It is larger than the area of each sub-pixel 49 (see FIG. 4B) of the density pixel.

  Here, each low-density pixel of the first modification is thinned out of the first sub-pixel 49R or the third sub-pixel 49B. Therefore, the low-density pixel group 47Bd has a smaller number of first sub-pixels 49R and third sub-pixels 49B than the high-density pixel group 47A. Therefore, in the first modification, the resolution in the low density area 54d is lower than that in the high density area 52 (the image quality becomes rough). In this case, the boundary between the low-density area 54d and the high-density area 52 is visually recognized, and there is a possibility that degradation of image quality is visually recognized. In the display device 10d according to the first modification, the signal processing unit 20d causes the resolution in the low-density region 54d to approximate the high-density region 52 in a pseudo manner, so that sub-pixel rendering processing (hereinafter referred to as rendering processing) and smoothing are performed. Execute the process. This will be specifically described below.

  FIG. 22 is a block diagram illustrating a configuration of a signal processing unit according to the first modification. As illustrated in FIG. 22, the signal processing unit 20 d includes a region information acquisition unit 21 d, an output signal generation unit 22 d, a processing determination unit 26, a rendering processing unit 27, and a smoothing processing unit 28.

  The area information acquisition unit 21d stores information on which pixels 48 are pixels included in the boundary area 57 in addition to information on which pixels 48 are high-density pixels 48A. FIG. 23 is a schematic diagram schematically showing the configuration of the image display panel according to the first modification. The boundary region 57 is a partial region of the high density region 52d and is adjacent to the low density region 54d. Specifically, as shown in FIG. 23, the boundary region 57A is a partial region of the high-density region 52d and is adjacent to the low-density region 54Ad. The boundary region 57B is a partial region of the high density region 52d and is adjacent to the low density region 54Bd. The high-density region 52d has a region 58 between the boundary region 57A and the boundary region 57B. The area and shape of the boundary regions 57A and 57B and the number of high-density pixels 48A included are arbitrary, but are stored in advance in the region information acquisition unit 21d. The boundary regions 57A and 57B preferably have a smaller area than the region 58.

  The process determination unit 26 acquires information on which pixels 48 are high-density pixels 48A and information on which pixels 48 are pixels included in the boundary region 57 from the region information acquisition unit 21d, and All the pixels 48 of the display panel 40d are classified as low-density pixels 48Bd, high-density pixels 48A in the boundary region 57, or high-density pixels 48A in the region 58. Decide to perform different processing on the input signal to generate the output signal. Specifically, the processing determination unit 26 performs rendering processing on the low density pixels 48Bd, performs smoothing processing on the high density pixels 48A in the boundary region 57, and performs decompression processing on the high density pixels 48A in the region 58. To decide. The process determining unit 26 outputs information (coordinate information) of the low-density pixel 48Bd that performs the rendering process to the rendering processor 27. The process determination unit 26 outputs information (coordinate information) of the high-density pixel 48A that performs the smoothing process to the smoothing process unit 28. The process determining unit 26 outputs information (coordinate information) of the high-density pixel 48A that performs the expansion process to the output signal generating unit 22d. The output signal generator 22d generates an output signal by the same expansion process as in the first embodiment.

The rendering processing unit 27 performs rendering processing on the input signal of each subpixel 49 included in the low density pixel 48Bd based on the information from the processing determination unit 26, and outputs it to each subpixel 49 of the low density pixel 48Bd. Generate an output signal. The rendering process is an image process in which an input signal of each sub-pixel 49 of the low-density pixel 48Bd is applied not only to the sub-pixel 49 in the self-pixel but also to a sub-pixel of the same color around the self-pixel. This is a method, and the resolution of the low density pixel 48Bd can be approximated to that of the high density pixel 48A. For example, the rendering processing unit 27, a low-density pixel _{48Bd (p, q)} of the predetermined position the first output signal value _{X 1- (p, q)} of the sub-pixels 49R of the input signal value x of the first sub-pixel 49R _{1- (p, q)} is calculated by averaging the input signal value of the first sub-pixel 49R of the surrounding pixel 48. Rendering processing unit 27, an output signal value _{X 2- (p, q)} of the second sub-pixel 49G, and the output signal value _{X 3- (p, q)} of the third sub-pixel 49B is also calculated in a similar manner . Hereinafter, an example of rendering processing will be described.

FIG. 24 is an explanatory diagram for explaining an example of rendering processing. In the low density region 54dx described in the upper part of FIG. 24, it is assumed that the low density pixel 48Bd is composed of three subpixels (first subpixel 49R, second subpixel 49G, and third subpixel 49B). The sub-pixel arrangement is shown. In the low density region 54d described below in FIG. 24, the low density pixel 48Bd has the sub-pixel arrangement described in the first modification. Here, an example of rendering processing for the first sub-pixel 49R of the low-density pixel 48Bd _{(a + 1, b + 1)} in the low-density region 54d of FIG. 24 will be described. The rendering processing unit 27 uses the output signal value X1- _{(a + 1, b + 1)} of the first sub-pixel 49R of the low density pixel 48Bd _{(a + 1, b + 1)} as the low density pixel 48Bd _{(a, b)} , 48Bd _{(a + 1, b). )} , 48Bd _{(a + 2, b)} , 48Bd _{(a, b + 1)} , 48Bd _{(a + 1, b + 1)} , 48Bd _{(a + 2, b + 1)} , 48Bd _{(a, b + 2)} , 48Bd _{(a + 1, b + 2)} , 48Bd _{(a + 2, b + 2)} Is calculated based on the input signal value of the first sub-pixel 49R. Low density pixels 48Bd _{(a, b)} , 48Bd _{(a + 1, b)} , 48Bd _{(a + 2, b)} , 48Bd _{(a, b + 1)} , 48Bd _{(a + 2, b + 1)} , 48Bd _{(a, b + 2)} , 48Bd _{(a + 1, b + 2) ), 48Bd (a + 2,} b + 2) , as shown in the low density region 54dx in FIG. 24, a low-density pixels around a low-density pixel _{48Bd (a + 1, b +} 1). Specifically, the rendering processing unit 27, a low-density pixel _{48Bd (a + 1, b +} 1) first output signal value of the sub-pixels 49R of _{X 1- (a + 1, b} + 1), calculated from the following equation (9).

X _{1- (a + 1, b + 1)} = 0.0625 · {(− 1) · x _{1- (a, b)} + 2 · x _{1- (a + 1, b)} + (− 1) · x _{1- (a + 2, b )} + 2 · x _{1- (a, b + 1)} + 12 · x _{1- (a + 1, b + 1)} + 2 · x _{1- (a + 2, b + 1)} + (− 1) · x _{1- (a, b + 2)} + 2 · x _{1− (A + 1, b + 2)} + (− 1) · x _{1− (a + 2, b + 2)} } (9)

As shown in Expression (9), the output signal value X _{1− (a + 1, b + 1)} of the first sub-pixel 49R is calculated from the average of the input signals of the surrounding sub-pixels. The coefficient (12 in equation (9)) applied to the input signal value x _{1− (a + 1, b + 1)} of 48Bd _{(a + 1, b + 1)} is larger than the coefficient applied to the input signal value of the surrounding pixels. This means that weighting is performed in the averaging process, and the weighting of the input signal value of its own pixel is greater than the weighting of the input signal value of surrounding pixels. . Similarly, the low density pixels 48Bd _{(a + 1, b )} , 48Bd _{(a, b + 1)} , 48Bd _{(a + 2, b + 1)} , 48Bd _{(a + 1, b + 2 )} adjacent to the low density pixel 48Bd _{(a + 1, b + 1)} in the X direction or the Y direction. weighting to the input _signal), the low density pixel _{48Bd (a + 1, b +} 1) a low density pixel _48Bd located diagonal _{(a, b), 48Bd (} a + 2, b), 48Bd (a, b + 2), 48Bd ( _{a + 2, b + 2)} . The rendering processing unit 27 performs the rendering process on the third sub-pixel 49B illustrated in FIG. 24 in the same manner, but does not perform the rendering process on the second sub-pixel 49G illustrated in FIG. The rendering process described above is an example, and for example, a coefficient applied to each input signal value can be arbitrarily set.

  Based on the information from the processing determination unit 26, the smoothing processing unit 28 performs the above-described expansion processing on the input signal of each sub-pixel 49 included in the high-density pixel 48A in the boundary region 57 to generate an output signal. Perform smoothing processing (dithering processing). The smoothing process is a process of gradually reducing the number of sub-pixels 49 that are turned on toward the low density region 54d. Hereinafter, a specific example of the smoothing process will be described.

  FIG. 25 is an explanatory diagram for explaining the smoothing process. In FIG. 25, when an input signal for lighting all the first sub-pixels 49R in the low density area 54Ad and the high density area 52d (the boundary area 57A and the area 58) is input, the smoothing process is performed on the boundary area 57A. In this case, the lighting state of the sub-pixel 49 is shown. As shown in FIG. 25, in the low density region 54Ad, all the first sub-pixels 49R are lit. Also, all the first sub-pixels 49R are lit even in the region 58 where the smoothing process is not performed. As described above, the low density pixel group 47Bd in the low density region 54Ad has a smaller number of first sub-pixels 49R than the high density pixel group 47A in the region 58. Therefore, the number of lighting of the first sub-pixel 49R in the low density area 54Ad is smaller than the number of lighting of the first sub-pixel 49R in the area 58.

  Here, the smoothing process is performed in the boundary region 57A between the low density region 54Ad and the region 58. Since the pixels in the boundary area 57A are high-density pixels 48A, the number of lighting of the sub-pixels 49 is the same as that of the area 58, but the number of lighting of the first sub-pixel 49R in the actual boundary area 57A is determined by the smoothing process. It gradually decreases toward the low density region 54d. Specifically, the number of lighting of the first sub-pixel 49R in the boundary area 57A is the same as the number of lighting of the first sub-pixel 49R in the area 58 at the boundary with the area 58, and as it goes toward the low density area 54Ad. , Gradually decrease. The number of lighting of the first sub-pixel 49R in the boundary area 57A is the same as the number of lighting of the first sub-pixel 49R in the low-density area 54Ad at the boundary with the low-density area 54Ad.

  When the smoothing process is not performed, the boundary between the low-density area 54Ad and the high-density area 52d is visually recognized, and there is a possibility that the image quality may be deteriorated. However, the display device 10d may be connected to the low-density area 54Ad by the smoothing process. It can suppress that the boundary with the high-density area | region 52d is visually recognized.

  Hereinafter, the process of generating an output signal by the signal processing unit 20d will be described with reference to a flowchart. FIG. 26 is a flowchart illustrating a process of generating an output signal by the signal processing unit according to the first modification. As illustrated in FIG. 26, the signal processing unit 20d acquires region information by the region information acquisition unit 21d (step S10). The area information is information regarding which pixels 48 are high-density pixels 48 </ b> A and information regarding which pixels 48 are pixels included in the boundary area 57.

  After acquiring the region information, the signal processing unit 20d determines whether the pixel 48 is the low density pixel 48Bd in the low density region 54d by the processing determination unit 26 (Step S12). When the pixel 48 is the low density pixel 48Bd in the low density region 54d (Yes in step S12), the signal processing unit 20d performs the rendering process on the pixel 48 by the rendering processing unit 27 (step S14). If the pixel 48 is not the low density pixel 48Bd in the low density region 54d (No in step S12), the signal processing unit 20d determines whether the pixel 48 is the pixel 48 in the boundary region 57 (step S16). ). When the pixel 48 is the pixel 48 in the boundary region 57 (Yes in Step S16), the signal processing unit 20d performs a smoothing process on the pixel 48 by the smoothing processing unit 28 (Step S18). When the pixel 48 is not the pixel 48 in the boundary region 57 (No in step S16), the signal processing unit 20d determines that the pixel 48 is a pixel in the region 58, and the output signal generation unit 22d performs an expansion process on the pixel 48. (Step S20). Thereby, this process is complete | finished.

  As described above, the signal processing unit 20d according to the first modification performs the sub-pixel rendering process for causing the output signal to be output to the low density pixel 48Bd to approximate the resolution to the high density pixel 48A in a pseudo manner. To generate. Thereby, even when the number of sub-pixels 49 included in the low-density pixel group 47Bd is smaller than the number of sub-pixels 49 of the same color included in the high-density pixel group 47A, the resolution in the low-density region 54d is simulated. By improving, it is suppressed that the boundary of the low density area | region 54d and the high density area | region 52 is visually recognized.

  In addition, the signal processing unit 20d performs a smoothing process on the high-density pixels 48A in the boundary region 57 so as to gradually reduce the number of sub-pixels 49 to be lit toward the low-density region 54d. Thus, even when the number of sub-pixels 49 included in the low-density pixel group 47Bd is smaller than the number of sub-pixels 49 of the same color included in the high-density pixel group 47A, the number of lightings gradually changes in the boundary region 57. Therefore, the boundary between the low density region 54d and the high density region 52 can be suppressed from being visually recognized.

  24 has a smaller density of subpixels than the high-density region 58, the space for installing the drive control circuit 60 is wider than the high-density region 58. In the low-density regions 54d and 54dx shown in FIG. Further, since the density of the sub-pixel is smaller in the low density area 54d than in the low density area 54dx, the space where the drive control circuit 60 can be installed is further wider than the low density area 54dx. Accordingly, when the scale of the drive control circuit 60 is large and it is difficult to dispose the drive control circuit 60 in the region of the low density region 54dx, the sub-pixel arrangement of the low density region 54d is adopted and the low density region 54d is adopted. It is preferable to install the drive control circuit 60 in the above. When the drive control circuit 60 is of a size that can be arranged in the low density region 54dx, the sub-pixel arrangement of the low density region 54dx is adopted to drive the drive control circuit in the low density region 54dx. 60 is preferably installed. When the sub-pixel arrangement of the low-density area 54d is adopted, the sub-pixel arrangement in the high-density area 52 may be an arrangement not including the sub-pixel arrangement of the low-density area 54dx, that is, the fourth sub-pixel 49W.

  The sub-pixel rendering process and the smoothing process may not be executed when the number of the first sub-pixels 49R and the third sub-pixels 49B included in the low-density pixel group 47Bd is the same as that of the high-density pixel group 47A. Good. For example, in the case of the sub-pixel arrangement according to the first embodiment, the sub-pixel rendering process and the smoothing process may not be executed. FIG. 27 is a diagram illustrating another example of the sub-pixel arrangement of the high-density pixels. Also, the sub-pixel rendering process and the smoothing process are executed even when the sub-pixel arrangement of the low-density pixel group 47Bd according to the first modification is the sub-pixel arrangement of the high-density pixel group 47Ae according to FIG. It does not have to be.

  As shown in FIG. 27, in this example, a high-density pixel group 47Ae in which high-density pixels 48A1e and high-density pixels 48A2e are arranged in two rows and two columns is arranged in a two-dimensional matrix within the high-density region 52e. Arranged. The high-density pixel group 47Ae has high-density pixels 48A1e in the first column of the first row, high-density pixels 48A2e in the second column of the first row, and high-density pixels in the first column of the second row. 48A2e and high-density pixels 48A1e in the second column of the second row.

  The high-density pixel 48A1e has the same sub-pixel arrangement as the high-density pixel 48A according to the first embodiment. On the other hand, the high-density pixel 48A2e includes a fifth subpixel 49C, a sixth subpixel 49M, a seventh subpixel 49Y, and a fourth subpixel 49W. The fifth sub-pixel 49C displays cyan as the fifth color. The sixth sub-pixel 49M displays magenta as the sixth color. The seventh sub-pixel 49Y displays yellow as the seventh color. However, the fifth color, the sixth color, and the seventh color are not limited to cyan, magenta, and yellow, respectively, and any color different from the first color, the second color, and the third color can be selected.

  As shown in FIG. 27, the high-density pixel 48A1e includes a fifth subpixel 49C, a sixth subpixel 49M, a seventh subpixel 49Y, and a fourth subpixel 49W arranged in two rows and two columns. Yes. The high-density pixel 48A1e has a sixth sub-pixel 49M in the first column of the first row, a seventh sub-pixel 49Y in the second column of the first row, and a fourth in the first column of the second row. It has a subpixel 49W, and has a fifth subpixel 49C in the second column of the second row. In other words, in the high-density pixel 48A1e, the sixth subpixel 49M is adjacent to the seventh subpixel 49Y in the row direction (X direction) and adjacent to the fourth subpixel 49W in the column direction (Y direction). The seventh sub pixel 49Y is adjacent to the fifth sub pixel 49C in the column direction (Y direction). The fourth subpixel 49W is adjacent to the fifth subpixel 49C in the row direction (X direction).

  The high-density pixel group 47Ae has the same number of first sub-pixels 49R and third sub-pixels 49B as the low-density pixel group 47Bd (see FIG. 21B). Therefore, as described above, in this case, the sub-pixel rendering process and the smoothing process need not be performed.

(Second modification)
Next, a second modification of the first embodiment will be described. The display device 10e of the second modification is different from the first embodiment in that it is a reflective liquid crystal display device. In the second modification, the description of the parts having the same configuration as that of the first embodiment is omitted.

  FIG. 28 is a block diagram illustrating an example of a configuration of a display device according to a second modification. As illustrated in FIG. 28, the display device 10e according to the second modification includes a signal processing unit 20, a signal output circuit 31, a scanning circuit 32, an image display panel 40e, and a light source unit 100. The image display panel 40e is a liquid crystal display panel. The light source unit 100 is incorporated in the frame portion 42 of the image display panel 40e. The light source unit 100 is a light source that emits light from the side surface of the image display panel 40e. The display device 10e displays an image by reflecting external light on the image display panel 40e. Furthermore, the display device 10e can also be used by reflecting the light emitted from the light source unit 100 on the image display panel 40e when used outdoors in the dark or when used in a dark place. Can be displayed.

  FIG. 29 is a diagram illustrating a sub-pixel drive circuit included in the pixel of the image display panel according to the second modification. The sub-pixel 49 in the second modification is driven by the drive circuit 45e. The drive circuit 45e is arranged in a two-dimensional matrix (matrix) like the lighting circuit 45 according to the first embodiment. As shown in FIG. 29, the drive circuit 45e includes a transistor Tr3, a liquid crystal capacitor C2, and a storage capacitor C3. The transistor Tr3 is a switch formed using, for example, a TFT. The transistor Tr3 has a gate electrode connected to one of the plurality of scanning lines SCL and a source electrode connected to one of the plurality of signal lines DTL.

  The liquid crystal capacitance C2 indicates a capacitance component of a liquid crystal element generated between a pixel electrode 108 and a counter electrode 110, which will be described later. The pixel electrode 108 is connected to the drain electrode of the transistor Tr3. The storage capacitor C <b> 3 has one electrode connected to the pixel electrode 108 and the other electrode connected to the counter electrode 110.

  Next, the structure of the image display panel 40e in the second modification will be described. FIG. 30A is a diagram schematically showing a cross-sectional structure of the image display panel in the high-density region in the second modified example. FIG. 30B is a diagram schematically showing a cross-sectional structure of the image display panel in the low density region in the second modification. FIG. 30A is a cross-sectional view at the same location as FIG. 6A of the first embodiment, and FIG. 30B is a cross-sectional view at the same location as FIG. 6B of the first embodiment. As shown in FIGS. 30A and 30B, the image display panel 40e includes a drive circuit 45e, a substrate 71, an insulating layer 72, a color filter 81, a counter substrate 104, a liquid crystal layer 106, a pixel electrode 108, The counter electrode 110 and the light guide plate 112 are provided. Here, a surface of the image display panel 40e that displays an image is a front surface 40e1, and a surface opposite to the front surface 40e1 is a back surface 40e2. The substrate 71 is provided on the back surface 40e2 side of the image display panel 40e. The substrate 71 is a semiconductor substrate such as silicon, a glass substrate, a resin substrate, or the like, and forms or holds the drive circuit 45e. The drive circuit 45e is provided for each sub-pixel 49, similarly to the lighting drive circuit 45 of the first embodiment. The circuit configuration of the drive circuit 45e will be described later. The insulating layer 72 is provided on the front surface 40e1 side of the substrate 71 and is a protective film that protects the above-described drive circuit 45e and the like, and silicon oxide, silicon nitride, or the like can be used.

  The counter substrate 104 is a substrate provided closer to the front surface 40 e 1 than the insulating layer 72. The counter substrate 104 is a transparent substrate such as glass. The liquid crystal layer 106 is provided between the insulating layer 72 and the counter substrate 104, and a liquid crystal element is sealed therein.

  The pixel electrode 108 is provided on the front surface 40 e 1 side, that is, on the liquid crystal layer 106 side with respect to the insulating layer 72. The pixel electrode 108 is connected to the signal line DTL via a switching element (transistor Tr3) described later, and an image output signal as a video signal is applied. The pixel electrode 108 is a reflective member made of, for example, aluminum or silver, and reflects external light or light from the light source unit 100. That is, the pixel electrode 108 constitutes a reflection part. The pixel electrode 108, that is, the reflection portion reflects light incident from the front surface 40e1 (surface on the image display side) of the image display panel 40e to display an image.

  The color filter 81 is provided on the surface on the back surface 40e1 side of the counter substrate 104, that is, the surface on the liquid crystal layer 106 side. The counter electrode 110 is provided on the liquid crystal layer 106 and is provided closer to the back surface 40 e 2 than the color filter 81. As shown in FIG. 30B, a black matrix 114 that shields light is provided between the color filters 81. The counter electrode 110 is a conductive material having transparency such as ITO or IZO. Since the pixel electrode 108 and the counter electrode 110 are provided to face each other, when a voltage based on an image output signal is applied between the pixel electrode 108 and the counter electrode 110, the pixel electrode 108 and the counter electrode 110 are An electric field is generated in the liquid crystal layer 106. The display device 10e adjusts the amount of light reflected from the image display panel 40e by changing the birefringence due to the electric field generated in the liquid crystal layer 106. The image display panel 40e is a so-called vertical electric field method, but may be a horizontal electric field method that generates an electric field in a direction parallel to the display surface of the image display panel 40e.

  A plurality of color filters 81 are provided corresponding to the pixel electrodes 108. The pixel electrode 108, the counter electrode 110, and the color filter 81 constitute a subpixel 49. The drive circuit 45 e is a circuit for driving the subpixel 49 and is not included in the subpixel 49. The light guide plate 112 is provided on the surface of the counter substrate 104 on the front surface 40e1 side. The light guide plate 112 is a transparent plate member such as an acrylic resin, a polycarbonate (PC) resin, or a methyl methacrylate-styrene copolymer (MS resin). The light guide plate 112 has a prism processed on the upper surface, which is the surface on the front surface 40e1 side.

  As shown in FIG. 30A, in the high density region 52, the drive circuit 45e and each wiring are provided below (on the back surface 40e2 side) below each sub pixel 49 (more specifically, the pixel electrode 108) of the high density pixel 48A. ing. As shown in FIG. 30B, in the low density region 54, the drive circuit 45e, each wiring, and the drive control circuit 60 are below (the back surface 40e2) below each sub pixel 49 (more specifically, the pixel electrode 108) of the low density pixel 48B. Side).

  The light source unit 100 includes a light emitting diode (LED). The light source unit 100 is provided on the front surface 40e1 side with respect to the sub-pixel 49, more specifically, the pixel electrode 108. That is, the display device 10e does not include the light source unit 100 on the back surface 40e2 side with respect to the pixel electrode 108 (reflecting unit). More specifically, the light source unit 100 is provided along the side surface of the light guide plate 112. The light source unit 100 irradiates light from the front surface 40 e 1 of the image display panel 40 through the light guide plate 112. The light source unit 100 is switched on (lit) and off (unlit) by an operation of an image observer or an external light sensor that is attached to the display device 10e and measures external light. The light source unit 100 emits light when turned on and does not emit light when turned off. For example, when the image observer feels that the image is dark, the image observer turns on the light source unit 100 and irradiates the image display panel 40e with light from the light source unit 100 to brighten the image. When the external light sensor determines that the external light intensity is smaller than a predetermined value, for example, the signal processing unit 20 turns on the light source unit 100 and irradiates the image display panel 40e with light from the light source unit 100. And brighten the image.

  Next, the reflection of light by the image display panel 40e will be described. As shown in FIGS. 30A and 30B, external light LO1 is incident on the image display panel 40e from the front surface 40e1 side. The external light LO1 enters the pixel electrode 108 through the light guide plate 112. The external light LO1 incident on the pixel electrode 108 is reflected by the pixel electrode 108, and is emitted to the outside as light LO2 through the light guide plate 112. Further, when the light source unit 100 is turned on, the light LI1 from the light source unit 100 enters the light guide plate 112 from the side surface of the light guide plate 112. The light LI1 that has entered the light guide plate 112 is scattered and reflected by the upper surface of the light guide plate 112, and a part of the light LI1 is applied to the pixel electrode 108 as light LI2. The light LI2 irradiated to the pixel electrode 108 is reflected by the pixel electrode 108 and is emitted to the outside through the light guide plate 112 as light LI3. Further, another part of the light scattered on the upper surface of the light guide plate 112 is reflected as the light LI4 and is repeatedly reflected in the light guide plate 112.

  That is, the pixel electrode 108 reflects outside light LO1 or light LI2 incident on the image display panel 40e from the front surface 40e1 of the image display panel 40e. The light LO2 and LI3 reflected to the outside pass through the liquid crystal layer 43 and the color filter 46. Therefore, the display device 10e can display an image with the light LO2 and LI3 reflected to the outside. Thus, the display device 10 e is a reflective liquid crystal display device having the sidelight type light source unit 100. The display device 10e may not include the light source unit 100 and the light guide plate 112. In this case, the display device 10e can display an image with the light LO2 reflected from the external light LO1.

  As described above, the display device 10e according to the second modification is a display device having the image display panel 40e in which the pixels 48 having a plurality of sub-pixels 49 are arranged in a two-dimensional matrix. The sub-pixel 49 in the second modified example has a pixel electrode 108 that reflects light from the front surface 40e1 of the image display panel 40e, that is, a reflection portion. The image display panel 40e displays an image with light from the front surface 40e1 reflected by the pixel electrode 108. The image display panel 40e includes a low density region 54 having low density pixels 48B and a high density region 52 having high density pixels 48A. The image display panel 40e does not have the light source unit 100 that emits light on the back surface 40e2 side of the pixel electrode 108.

  The display device 10e does not have the light source unit 100 on the back surface 40e2 side of the pixel electrode 108, and displays an image by reflecting light from the front surface 40e1 side of the pixel electrode 108. Accordingly, in the display device 10e as well, the light is not blocked by the wiring as in the first embodiment, so that the decrease in the aperture ratio of the high density region 52 is suppressed, and the aperture ratio of the high density region 52 and the low density region 54 is suppressed. Can be reduced. Therefore, the display device 10 suppresses that the brightness of the image is different for each region, and suppresses deterioration in image quality.

  In addition, a signal for driving the sub-pixel 49 is input to the sub-pixel 49 via wiring (scanning line SCL, signal line DTL). The wiring is provided below the pixel electrode 108 (on the back surface 40e2 side) with respect to the image display surface 50. Therefore, in the display device 10, the light traveling from the pixel electrode 108 to the outside does not travel to the wiring. For this reason, the display device 10e more preferably suppresses light from being blocked by the wiring, and more preferably suppresses deterioration in image quality.

  The reflective liquid crystal display device described in the second modification can also be applied to embodiments and modifications other than the first embodiment. That is, the display device according to the present disclosure may be a reflective liquid crystal display device instead of the self-luminous display device. However, in this case, the light source unit 100 is not provided on the back surface 40e2 side with respect to the pixel electrode 108.

(Application example)
Next, an application example of the display device 10 described in the first embodiment will be described with reference to FIGS. 31 and 32. 31 and 32 are diagrams illustrating an example of an electronic apparatus to which the display device according to the first embodiment is applied. The display device 10 according to the first embodiment includes electronic devices in all fields such as a car navigation system, a television device, a digital camera, a notebook personal computer, a mobile terminal device such as a mobile phone illustrated in FIG. It can be applied to equipment. In other words, the display device 10 according to the first embodiment can be applied to electronic devices in various fields that display an externally input video signal or an internally generated video signal as an image or video. The electronic device includes a control device 11 (see FIG. 1) that supplies a video signal to the display device and controls the operation of the display device. Note that this application example can be applied to display devices according to other embodiments and modifications described above, in addition to the display device 10 according to the first embodiment.

  The electronic apparatus shown in FIG. 31 is a car navigation device to which the display device 10 according to the first embodiment is applied. The display device 10 is installed on a dashboard 300 in a car. Specifically, it is installed between the driver's seat 311 and the passenger seat 312 of the dashboard 300. The display device 10 of the car navigation device is used for navigation display, music operation screen display, movie playback display, and the like.

  The electronic apparatus illustrated in FIG. 32 operates as a portable computer to which the display device 10 according to the first embodiment is applied, a multifunctional mobile phone, a portable computer capable of voice communication, or a portable computer capable of communication, and is a so-called smartphone or tablet. It is a portable information terminal, sometimes called a terminal. This information portable terminal has a display unit 561 on the surface of a housing 562, for example. The display unit 561 includes the display device 10 according to the first embodiment and a touch detection (so-called touch panel) function capable of detecting an external proximity object.

  As mentioned above, although embodiment of this invention was described, these embodiment is not limited by the content of these embodiment. In addition, the above-described constituent elements include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those in a so-called equivalent range. Furthermore, the above-described components can be appropriately combined. Furthermore, various omissions, substitutions, or changes of the components can be made without departing from the spirit of the above-described embodiment.

  The present disclosure can employ the following configurations.

(1) Pixels having a plurality of sub-pixels having a self-luminous layer are arranged in a two-dimensional matrix,
A low density region having low density pixels that are pixels having a first number of subpixels, and a high density region having high density pixels having a second number of subpixels greater than the first number; And a lighting drive circuit for lighting the self-light-emitting layer.

(2) A signal for driving the sub-pixel is input to the sub-pixel via a wiring.
The display device, wherein the wiring is provided below the self-luminous layer with respect to the image display surface.

  (3) The display device, wherein the low density region further includes a drive control circuit for controlling driving of the lighting drive circuit, and the high density region does not include the drive control circuit.

  (4) The display device, wherein the drive control circuit is provided below the self-luminous layer with respect to the image display surface.

  (5) The display device, wherein the lighting drive circuit is provided in the same layer as the drive control circuit.

(6) The high-density region is provided in the center of the image display surface,
The display device, wherein the low density region is provided at both ends of the high density region in the image display surface.

  (7) The display device, wherein the image display surface occupies the entire area of the image display panel along a predetermined direction.

  (8) The display device, wherein the drive control circuit is a scanning circuit that sequentially selects the sub-pixels to light the self-light-emitting layer.

  (9) The display device, wherein the low density regions are provided in a scattered manner in the high density region.

  (10) The display device, wherein the drive control circuit includes a sensor for controlling driving of the image display panel.

  (11) The display device, wherein an area of a sub-pixel of the low-density pixel is larger than an area of a sub-pixel of the high-density pixel.

  (12) The display device further including a signal processing unit that generates an output signal to be output to the low-density pixels by performing a sub-pixel rendering process.

  (13) The signal processing unit is a sub-pixel that is lit for the high-density pixel in a boundary region that is a partial region in the high-density region and is in a predetermined range adjacent to the low-density region. The display device is configured to perform a smoothing process that gradually decreases the number of the light sources toward the low density region.

(14) A display device having an image display panel in which pixels having a plurality of subpixels are arranged in a two-dimensional matrix,
The sub-pixel has a reflection part that reflects light from the front surface of the image display panel,
The image display panel displays an image by light from the front surface reflected by the reflection unit, and includes a low-density region having low-density pixels that are pixels having a first number of the sub-pixels, and the first A high-density region having a high-density pixel having a second number of the sub-pixels greater than the number, and a light source unit that irradiates light on the back side opposite to the front side of the reflection unit Without a display device.

(15) The sub-pixel receives a signal for driving the sub-pixel via a wiring,
The display device, wherein the wiring is provided below the reflection unit with respect to the image display surface.

DESCRIPTION OF SYMBOLS 10 Display apparatus 20 Signal processing part 30 Image display panel drive part 40 Image display panel 48 Pixel 48A High density pixel 48B Low density pixel 52 High density area 54 Low density area 49R 1st subpixel 49G 2nd subpixel 49B 3rd subpixel 49W 4th sub-pixel

Claims (15)

Pixels having a plurality of sub-pixels having a self-luminous layer are arranged in a two-dimensional matrix,
A low density region having low density pixels that are pixels having a first number of subpixels, and a high density region having high density pixels having a second number of subpixels greater than the first number; And a lighting drive circuit for lighting the self-light-emitting layer. The sub-pixel receives a signal for driving the sub-pixel via a wiring,
The display device according to claim 1, wherein the wiring is provided below the self-luminous layer with respect to the image display surface.   The display device according to claim 2, wherein the low density region further includes a drive control circuit for controlling driving of the lighting drive circuit, and the high density region does not include the drive control circuit.   The display device according to claim 3, wherein the drive control circuit is provided below the self-luminous layer with respect to the image display surface.   The display device according to claim 4, wherein the lighting drive circuit is provided in the same layer as the drive control circuit. The high-density region is provided in the center of the image display surface,
The display device according to claim 4, wherein the low density region is provided at both ends of the high density region in the image display surface.   The display device according to claim 6, wherein the image display surface occupies the entire area of the image display panel along a predetermined direction.   The display device according to claim 7, wherein the drive control circuit is a scanning circuit that sequentially selects the sub-pixels to light the self-light-emitting layer.   The display device according to claim 4, wherein the low density region is provided in a scattered manner in the high density region.   The display device according to claim 9, wherein the drive control circuit includes a sensor for controlling driving of the image display panel.   11. The display device according to claim 1, wherein an area of a sub-pixel of the low-density pixel is larger than an area of a sub-pixel of the high-density pixel.   12. The display device according to claim 1, further comprising a signal processing unit that generates an output signal to be output to the low-density pixels by performing a sub-pixel rendering process.   The signal processing unit determines the number of sub-pixels to be lit for the high-density pixels in a boundary region that is a partial region in the high-density region and is adjacent to the low-density region. The display device according to claim 12, wherein smoothing processing that gradually decreases toward the low density region is performed. A display device having an image display panel in which pixels having a plurality of sub-pixels are arranged in a two-dimensional matrix,
The sub-pixel has a reflection part that reflects light from the front surface of the image display panel,
The image display panel displays an image by light from the front surface reflected by the reflection unit, and includes a low-density region having low-density pixels that are pixels having a first number of the sub-pixels, and the first A high-density region having a high-density pixel having a second number of the sub-pixels greater than the number, and a light source unit that irradiates light on the back side opposite to the front side of the reflection unit Without a display device. The sub-pixel receives a signal for driving the sub-pixel via a wiring,
The display device according to claim 14, wherein the wiring is provided below the reflection unit with respect to the image display surface.

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