Signal processing device, signal processing method, and display device

Abstract

The present technology relates to a signal processing device, a signal processing method, and a display device that make it possible to provide functions suitable for uses. Provided is a signal processing device equipped with a signal processing unit that acquires at least one information among first information relating to the color of an image displayed on a panel part, second information relating to the brightness of a screen of the panel part, and third information measured as a physical quantity relating to the panel part, and on the basis of the acquired information, adaptively controls voltage for driving the panel part according to the load and use of the panel part. The present technology can be applied to, for example, a self-luminous display device.

Description

Technical Field

[0001] The present technology relates to a signal processing device, a signal processing method, and a display device, and particularly to a signal processing device, a signal processing method, and a display device capable of performing control adapted to applications.

Background Art

[0002] In recent years, self-emitting display devices such as OLED display devices have been becoming the mainstream as display devices for displaying images. For example, Patent Document 1 discloses a technology for reducing power consumption as a technology related to an OLED display device.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in display devices such as self-emitting display devices, it is required to perform control adapted to applications such as realizing low power consumption.

[0005] The present technology has been made in view of such a situation, and enables control adapted to applications.

Means for Solving the Problems

[0006] The signal processing device of the first aspect of this technology includes a signal processing unit that acquires first information including information about the HSV color space components of a video signal corresponding to an image displayed on a panel unit in which pixels including self-emissive elements are arranged in two dimensions, and second information including an average pixel level indicating the brightness of the entire screen of the panel unit, and controls a voltage for driving the panel unit based on the acquired first and second information, and the signal processing unit detects a state in which the value of the average pixel level is lower than a first reference value based on the second information ,moreover, The panel section The light-emitting region of the pixel is relatively compared to a predetermined region. In a small state can be Furthermore, based on the first information, the HSV color space Load according to hue component The video signal is smaller than the second reference value. Brightness component When a condition is detected that is higher than the third reference value. 、 This is a signal processing device that increases the aforementioned voltage.

[0007] This technology First aspect Signal processing method , and the display device of the first aspect of this technology teeth, A signal processing method and a display device corresponding to the signal processing device of the first aspect of the present technology described above. .

[0008] The signal processing device of the second aspect of this technology includes a signal processing unit that acquires first information including information about the HSV color space components of a video signal corresponding to an image displayed on a panel unit in which pixels including self-emissive elements are arranged in two dimensions, and second information including an average pixel level indicating the brightness of the entire screen of the panel unit, and controls a voltage for driving the panel unit based on the acquired first and second information, and the signal processing unit detects a state in which the value of the average pixel level is higher than a first reference value based on the second information ,moreover, The panel section The light-emitting region of the pixel is relatively compared to a predetermined region. Large can be Furthermore, based on the first information, the HSV color space Load according to hue component The video signal is greater than the second reference value. Brightness component When a condition is detected that is higher than the third reference value. 、 This is a signal processing device that reduces the aforementioned voltage.

[0009] The signal processing method and the display device of the second aspect of this technology are the signal processing method and the display device corresponding to the signal processing device of the second aspect of this technology described above. .

[0011] The signal processing device and the display device of this technology The first aspect and the second aspect may be independent devices or internal blocks constituting one device.

Brief Description of Drawings

[0012] [Figure 1] It is a diagram showing the relationship between the color components and current values of each pixel. [Figure 2] It is a diagram showing an example of function implementation in a timing controller. [Figure 3] It is a diagram showing an example of function implementation in a set substrate. [Figure 4] It is a diagram showing an example of the screen brightness of a panel part by a panel drive voltage. [Figure 5] It is a diagram schematically showing the relationship between the power wiring and current supply of a panel part. [Figure 6] It is a block diagram showing a configuration example of an embodiment of a display device to which this technology is applied. [Figure 7] It is a block diagram showing a detailed configuration example of a signal processing unit. [Figure 8] It is a diagram showing an example of the color expression range of a video signal. [Figure 9] It is a diagram showing an example of gain control linked to hue. [Figure 10] It is a diagram showing an example of gain control linked to saturation. [Figure 11] It is a diagram showing an example of gain control linked to lightness. [Figure 12] It is a diagram showing a first example of the relationship between APL and emission luminance in a panel part. [Figure 13] It is a diagram showing a second example of the relationship between APL and emission luminance in a panel part. [Figure 14] It is a diagram showing a configuration example of one temperature sensor provided for a panel part. [Figure 15] It is a diagram showing a configuration example of a plurality of temperature sensors provided for a panel part. [Figure 16] This figure shows an example configuration of multiple current sensors provided on the panel. [Figure 17] This is a flowchart illustrating the flow of the panel drive voltage control process. [Figure 18] This figure shows a specific configuration example of a display device to which this technology is applied. [Figure 19] This is a block diagram showing other configuration examples for the signal processing unit. [Modes for carrying out the invention]

[0013] <1. Embodiments of this technology>

[0014] (lower power consumption) In OLED display devices, a technique for reducing power consumption is known to measure the APL (Average Picture Level) and maximum grayscale value of the image and adjust the reference gamma voltage and drive voltage accordingly. However, when using this type of technique, the judgment process is performed using only the measured APL and maximum grayscale value, so it is not possible to consider the differences in the amount of current required for light emission from each pixel on the display panel, and therefore it is not possible to grasp the overall load on the display panel screen.

[0015] In a display panel, each pixel arranged in a two-dimensional plane can be composed of four subpixels: white (W), red (R), green (G), and blue (B), or of three subpixels: red (R), green (G), and blue (B). Hereinafter, the method in which each pixel is a WRGB pixel will be called the WRGB method, and the method in which each pixel is an RGB pixel will be called the RGB method.

[0016] In a display panel compatible with the WRGB system, each pixel receives a different current depending on the light emission level of each color: white (W), red (R), green (G), and blue (B). Similarly, in a display panel compatible with the RGB system, each pixel receives a different current depending on the light emission level of each color: red (R), green (G), and blue (B). Therefore, when understanding the overall load on a display panel screen, it is difficult to accurately understand (predict) it without also considering color-related information.

[0017] Figure 1 shows the relationship between the color components of each pixel and the current value. In Figure 1, the horizontal axis represents the subpixel color (White, Red, Green, Blue) and the color when two subpixels are lit (Yellow, Cyan, Magenta), and the vertical axis represents the panel drive current value. For each pixel, when subpixels R and G are lit, the color becomes yellow (Y); when subpixels R and B are lit, the color becomes magenta (M); and when subpixels G and B are lit, the color becomes cyan (C).

[0018] In Figure 1, the vertical bars representing each color component show the current value for each color component. From this bar graph, it can be seen that the current value differs for each color component. In particular, the increase in current value is significant for yellow (Y), magenta (M), and cyan (C) because two subpixels are lit.

[0019] Furthermore, OLED display devices are equipped with a timing controller (T-CON) for the display panel. When functions are implemented using this timing controller, because it has frame memory, there is no delay difference between the voltage drive and the video signal, but a delay due to the transient response of the power supply inevitably occurs. Therefore, there is a problem in that real-time processing is not possible.

[0020] Specifically, Figure 2 shows a configuration in which the function is realized by a timing controller 13 provided for the panel unit 14. In the configuration of Figure 2, the timing controller 13 controls the panel drive voltage via the power supply unit 12, but since the video signal processed by the signal processing unit 11 is held in the frame memory 22, it is difficult to control the voltage drive and the video signal simultaneously.

[0021] Figure 3 shows the configuration when the functionality is realized by the signal processing unit 11, which is configured as a video SoC on the set board. In the configuration of Figure 3, the signal processing unit 11 controls the panel drive voltage via the power supply unit 12, so the timing controller 13 has a margin for the frame buffer provided by the frame memory 22.

[0022] (Increased brightness) In OLED display devices, increasing the panel drive voltage is necessary to achieve stable high brightness. For example, when trying to achieve high brightness with images such as window patterns, if the voltage is too low, the brightness of the central part of the display panel will not increase, resulting in brightness differences depending on the screen position.

[0023] Figure 4 shows an example of screen brightness of the panel unit 14 based on the panel driving voltage. In Figure 4, the horizontal axis corresponds to the screen height of the panel unit 14, with the approximate center corresponding to the center of the screen in the height direction, and moving to the left of the horizontal axis brings you closer to the top of the screen, while moving to the right of the horizontal axis brings you closer to the bottom of the screen. The vertical axis represents brightness, with higher brightness indicating greater brightness and lower brightness indicating less brightness.

[0024] In Figure 4, the thick lines L11 to L13 represent screen brightness according to the panel drive voltage. Thick line L11 represents the case when the panel drive voltage is V11, thick line L12 represents the case when the panel drive voltage is V12, and thick line L13 represents the case when the panel drive voltage is V13. However, these panel drive voltages have the relationship V11 > V12 > V13.

[0025] Here, when attempting to achieve high brightness with an image such as a window pattern, if the panel drive voltage is low (V12 and V13 have lower voltage values ​​than V11), as shown by the thick lines L12 and L13, the brightness of the central part of the panel 14 will not increase, resulting in a brightness difference. For example, when the panel drive voltage shown by the thick line L12 is V12, the brightness of the central part of the screen is lower by a predetermined percentage, such as a few percent (for example, about 7% in Figure 4), compared to the parts closer to the top and bottom of the screen.

[0026] This is caused by the difference in current supply between the illuminated and unilluminated parts of the panel unit 14's screen, although this also depends on the power wiring of the panel unit 14. To increase brightness, it is necessary to increase the panel drive voltage (for example, by raising the panel drive voltage to V11 as shown by the thick line L11 in Figure 4).

[0027] Figure 5 schematically shows the relationship between the power wiring and current supply of the panel unit 14. When displaying an image of a window pattern (white area in the figure) as shown in Figure 5A on the panel unit 14, the relationship between the power wiring and current supply of the panel unit 14 is as shown in Figure 5B. However, the dashed rectangle in Figure 5B corresponds to the window pattern in Figure 5A.

[0028] In other words, in Figure 5B, the flow of current I through the power wiring 31 of the panel section 14 is shown by a U-turn arrow. Due to the current supply from outside the window pattern area, the voltage drop at the top and bottom of the screen is smaller than at the center of the screen. However, because current does not flow easily at the center of the screen, the brightness does not increase, and it is necessary to increase the panel drive voltage to increase the brightness.

[0029] (Suppression of temperature rise) Furthermore, with OLED display devices, simply increasing the panel drive voltage to increase brightness will increase power consumption. Therefore, if the panel drive voltage is constantly increased, the temperature of the display panel will rise, resulting in a prolonged high-load state and leading to reliability problems such as screen burn-in.

[0030] This technology proposes a method for solving the problems described above. The embodiments of this technology will be described below with reference to the drawings.

[0031] (Device configuration) Figure 6 shows an example configuration of one embodiment of a display device to which this technology is applied.

[0032] Display device 1 is a self-emissive display device, such as an OLED display device having an OLED panel. Display device 1 is configured as a television receiver or the like.

[0033] In Figure 6, the display device 1 consists of a signal input unit 110, a signal processing unit 111, a power supply unit 112, a panel drive unit 113, and a panel unit 114.

[0034] The signal input section 110 consists of a tuner connected to an antenna, a communication module that can connect to a communication network such as the Internet, or an input interface that conforms to a predetermined standard.

[0035] The signal input unit 110 supplies video signals of various types of content to the signal processing unit 111, such as broadcast content transmitted by terrestrial broadcasting or satellite broadcasting, communication content streamed via communication networks such as the Internet, or recorded content stored on recording media such as optical discs or semiconductor memory, or on recording devices.

[0036] The signal processing unit 111 performs video signal processing on the video signal of the content supplied from the signal input unit 110, and supplies the resulting video signal to the panel drive unit 113. The signal processing unit 111 also controls the panel drive voltage via the power supply unit 112 for the panel drive unit 113 to drive the panel unit 114.

[0037] The panel drive unit 113 drives the panel unit 114 based on the video signal supplied from the signal processing unit 111 and the panel drive voltage controlled by the signal processing unit 111. The panel drive unit 113 also measures the surface temperature and current of the panel unit 114 and supplies the measurement results to the signal processing unit 111.

[0038] The panel unit 114 is a display panel such as an OLED panel. The panel unit 114 displays images according to the video signals of various content, in accordance with the drive from the panel drive unit 113.

[0039] An OLED panel is a display panel in which pixels, including OLED elements as self-emissive elements, are arranged in a two-dimensional manner. An OLED (Organic Light Emitting Diode) is a light-emitting element with a structure in which an organic light-emitting material is sandwiched between a cathode and an anode, and it constitutes the pixels (display pixels) arranged in a two-dimensional manner on an OLED panel.

[0040] In an OLED panel, each pixel (display pixel) is composed of four subpixels: white (W), red (R), green (G), and blue (B) in the WRGB system, and three subpixels: red (R), green (G), and blue (B) in the RGB system.

[0041] Note that the configuration shown in Figure 6 is a minimal setup for the sake of simplicity, but it may include other circuits and devices such as an audio signal processing circuit that processes the audio signal, or a speaker that outputs sound corresponding to the audio signal.

[0042] Figure 7 shows a detailed configuration example of the signal processing unit 111 in Figure 6.

[0043] In Figure 7, the signal processing unit 111 includes a W conversion unit 131, a hue detection unit 132, a saturation detection unit 133, a brightness detection unit 134, an APL detection unit 135, and a voltage control unit 136.

[0044] In the signal processing unit 111, the video signal from the signal input unit 110 is supplied to the W conversion unit 131 and the APL detection unit 135, respectively. The video signal is also supplied to the panel drive unit 113.

[0045] The W conversion unit 131 performs a White conversion process on the video signal input thereto, and supplies the resulting W-converted video signal to the hue detection unit 132, the saturation detection unit 133, and the brightness detection unit 134, respectively.

[0046] The hue detection unit 132 performs hue detection processing on the video signal supplied from the W conversion unit 131 and supplies the resulting hue information to the voltage control unit 136. In this hue detection processing, the hue (H: Hue) component of the video signal's color space (HSV color space) is detected.

[0047] The saturation detection unit 133 performs saturation detection processing on the video signal supplied from the W conversion unit 131, and supplies the saturation information obtained as a result of this processing to the voltage control unit 136. In this saturation detection processing, saturation (S: Saturation) is detected among the components of the color space (HSV color space) of the video signal.

[0048] The brightness detection unit 134 performs brightness detection processing on the video signal supplied from the W conversion unit 131 and supplies the brightness information obtained as a result of this processing to the voltage control unit 136. In this brightness detection processing, the brightness (V: Value) component of the color space (HSV color space) of the video signal is detected.

[0049] The APL detection unit 135 performs APL detection processing on the video signal input thereto and supplies the APL information obtained as a result of this processing to the voltage control unit 136. In this APL detection processing, the average pixel level (APL) is detected based on the video signal. The average pixel level (APL) is a value that serves as an indicator of the overall brightness of the screen of the panel unit 114.

[0050] The voltage control unit 136 is supplied with hue information from the hue detection unit 132, saturation information from the saturation detection unit 133, brightness information from the brightness detection unit 134, and APL information from the APL detection unit 135. The voltage control unit 136 is also supplied with temperature information and current information from the panel drive unit 113.

[0051] The voltage control unit 136 adaptively controls the panel drive voltage for driving the panel unit 114 according to the load and application, based on at least one piece of information from among hue information, saturation information, brightness information, APL information, temperature information, and current information.

[0052] Here, the power supply unit 112 controls the panel drive voltage variably according to the control from the voltage control unit 136 and supplies it to the panel drive unit 113, so that the panel unit 114 is driven based on the applied panel drive voltage.

[0053] For example, the voltage control unit 136 performs control related to the HSV color space based on hue information, saturation information, and brightness information. Details of the control related to the HSV color space will be described later with reference to Figures 8 to 11. The voltage control unit 136 also performs control related to the brightness curve based on APL information. Details of the control related to the brightness curve will be described later with reference to Figures 12 and 13. In addition, the voltage control unit 136 controls the panel drive voltage based on temperature information and current information.

[0054] In Figure 7, the panel drive unit 113 includes a panel temperature measurement unit 151 and a panel current measurement unit 152.

[0055] The panel temperature measurement unit 151 supplies temperature information indicating the surface temperature of the panel 114, measured by a temperature sensor or the like provided on the panel 114, to the voltage control unit 136. An example of the temperature sensor configuration will be described later with reference to Figures 14 and 15.

[0056] The panel current measurement unit 152 supplies current information indicating the amount of current of the panel drive voltage applied to the panel unit 114, as measured by a current sensor or the like provided to the panel unit 114, to the voltage control unit 136. An example of the configuration of the current sensor will be described later with reference to Figure 16.

[0057] (HSV control) Figure 8 shows an example of the color representation range of a video signal.

[0058] In Figure 8, the color range of the video signal is represented in the HSV color space. The HSV color space is a color space consisting of three components: hue (H), saturation (S), and value (V). Here, hue refers to the type of color, saturation refers to the vividness of the color, and value refers to the brightness of the color.

[0059] In Figure 8, the HSV color space is represented by a cylinder 51. In this HSV color space cylinder 51, the azimuthal direction represents hue H, the radial direction represents chroma S, and the axial direction represents lightness V. Figure 8 shows a cropped section of the cross-section of hue H in the HSV color space.

[0060] In other words, the cylinder 51 of the HSV color space corresponds to the range of colors that can be represented by the four subpixels of white (W), red (R), green (G), and blue (B) in each pixel of the WRGB system, or the three subpixels of red (R), green (G), and blue (B) in each pixel of the RGB system.

[0061] In the display device 1, the current applied to each pixel in the panel unit 114 differs depending on the light emission level of the WRGB or RGB method. Therefore, in order to accurately understand the load on the panel unit 114, it is necessary to take color information into account.

[0062] Figure 9 shows an example of gain control linked to hue H. In Figure 9, the horizontal axis represents hue H, and the vertical axis represents hue-linked gain.

[0063] The hue H on the horizontal axis is represented by a value in the range of 0° to 360°. Specifically, hue 0° represents red, hue 60° represents yellow, hue 120° represents green, hue 180° represents cyan, hue 240° represents blue, and hue 300° represents magenta.

[0064] When controlling the hue-linked gain, the weight of the current load is determined for each hue H according to the characteristics of the OLED element in each pixel. Furthermore, complementary colors such as yellow (Y), cyan (C), and magenta (M) require the illumination of two RGB subpixels in each pixel, resulting in a larger load compared to when the RGB subpixels are illuminated in a single color, so the weight needs to be adjusted.

[0065] In Figure 9, the hue-linked gain corresponding to the hue H is shown by the thick line L21, which is represented by a triangular wave. For complementary colors, yellow (Y), cyan (C), and magenta (M), the hue-linked gain is set to 1.0x, and the weight is changed for the other colors.

[0066] In the voltage control unit 136, the panel drive voltage is adaptively controlled by adjusting the weight using a hue-linked gain corresponding to the hue information from the hue detection unit 132. This allows the load to be suppressed by adjusting the weight when, for example, two RGB subpixels light up due to a complementary color video signal.

[0067] Figure 10 shows an example of gain control linked to saturation S. In Figure 10, the horizontal axis represents saturation S, and the vertical axis represents saturation-linked gain.

[0068] The saturation S on the horizontal axis is represented by a value in the range of 0 to 1 (0% to 100%). Specifically, it is 0 for achromatic colors and increases as you move away from the achromatic axis, reaching a maximum for pure colors, depending on the distance from the central axis (achromatic axis) in the HSV color space cylinder 51.

[0069] When controlling the saturation-linked gain, the weights are controlled according to the intensity of the colors. In the WRGB system, since the luminescence efficiency of subpixel W is better than that of the other subpixels R, G, and B in each pixel, the weight needs to be considered more carefully for darker colors.

[0070] In Figure 10, the saturation-linked gain corresponding to the saturation S is shown by the thick line L31, which is an upward-sloping straight line. As the saturation S increases, the gain also increases at a constant rate, making it possible to change the weight in the saturation direction. This saturation-linked gain can be called a high-saturation-linked gain because the gain increases with higher saturation.

[0071] In the voltage control unit 136, the panel drive voltage is adaptively controlled by adjusting the weight using a saturation-linked gain corresponding to the saturation information from the saturation detection unit 133. This allows for reduced load in the case of the WRGB system, as the weight of darker colors is adjusted accordingly.

[0072] In the case of the RGB system, each pixel emits all of its sub-pixels (R, G, and B) to represent white (W), so lighter colors need to be given more weight. In this case, the saturation-linked gain corresponding to the saturation S can be represented by a downward-sloping straight line such that the gain increases at a constant rate as the saturation S decreases. This allows for weight adjustments to be made for lighter colors in the RGB system, thereby reducing the load.

[0073] Figure 11 shows an example of gain control linked to brightness V. In Figure 11, the horizontal axis represents brightness V, and the vertical axis represents brightness-linked gain.

[0074] The lightness V on the horizontal axis is represented by a value in the range of 0 to 1 (0% to 100%). Specifically, in the cylinder 51 of the HSV color space, lightness increases as you move upward in the height direction; higher lightness means it becomes brighter, while lower lightness means it becomes darker.

[0075] When controlling the brightness-linked gain, the weight is controlled according to the signal level of the video signal. In other words, for each pixel, if the light emission level simply increases, the load increases accordingly, so the brightness-linked gain is controlled in conjunction with this mechanism.

[0076] In Figure 11, the brightness-linked gain corresponding to the brightness V is shown by the thick line L41, which is a straight line sloping upwards to the right. As the brightness V increases, the gain also increases at a constant slope, making it possible to change the weight in the brightness direction. This brightness-linked gain can be called a high-brightness-linked gain because the gain increases with higher brightness.

[0077] In the voltage control unit 136, the panel drive voltage is adaptively controlled by adjusting the weight using a brightness-linked gain corresponding to the brightness information from the brightness detection unit 134. This allows the load to be suppressed by adjusting the weight when the light emission level of a pixel is high.

[0078] In this way, the voltage control unit 136 controls the gain (hue-linked gain, saturation-linked gain, brightness-linked gain) based on information (hue information, saturation information, brightness information) regarding each component (hue, saturation, brightness) of the video signal's color space (HSV color space), thereby adjusting the weight according to the load of each component (hue, saturation, brightness) in the video signal's color space (HSV color space).

[0079] (APL brightness control) In OLED display devices, the OLED panel has the characteristic that its brightness decreases in proportion to the overall brightness of the screen. This is because, in an OLED panel, pixels containing OLED elements are arranged in a two-dimensional manner, and as the light-emitting area increases, the total current of the screen increases. Therefore, while an OLED panel can emit light brightly when the light-emitting area is small, the overall light output decreases as the light-emitting area increases.

[0080] To take these characteristics of OLED display devices into account, the display device 1 needs to predict the load on the panel 114 according to the average pixel level (APL) which indicates the overall brightness of the panel 114, and weighting according to its light-emitting area is required.

[0081] Figures 12 and 13 show examples of the relationship between average pixel level (APL) and luminance in the panel section 114. In Figures 12 and 13, the horizontal axis represents average pixel level (APL), and the vertical axis represents luminance. The average pixel level (APL) on the horizontal axis is expressed as a value in the range of 0 to 100%.

[0082] In Figure 12, the control of peak brightness for subpixels R, G, and B according to the average pixel level (APL) is shown by the thick line L51. As shown by the thick line L51, represented by the curve in Figure 12, the emission brightness of subpixels R, G, and B gradually decreases as the value of the average pixel level (APL) increases.

[0083] In Figure 13, the control of peak brightness for subpixels W according to the average pixel level (APL) is shown by the thick line L61, represented by a curve. As shown by the thick line L61 in Figure 13, the emission brightness of subpixels W gradually decreases as the value of the average pixel level (APL) increases.

[0084] Furthermore, comparing the thick line L51 in Figure 12 with the thick line L61 in Figure 13, it can be seen that subpixel W has better luminescence efficiency than subpixels R, G, and B.

[0085] The voltage control unit 136 controls the brightness curve (e.g., thick lines L51, thick lines L61) based on the average pixel level (APL) obtained from the APL detection unit 135, and weights it according to the light-emitting area of ​​the panel section 114 (adjusting the weight according to the load of the panel section 114), thereby adaptively controlling the panel drive voltage. This enables the display device 1, which is configured as an OLED display device, to drive the panel section 114, which is configured as an OLED panel, according to its characteristics.

[0086] (Measurement of panel surface temperature) In the display device 1, not only is the video load predicted by signal processing performed by the signal processing unit 111, but the accuracy can also be improved by measuring the surface temperature of the panel unit 114 using a temperature sensor or the like.

[0087] Figure 14 shows an example configuration of a single temperature sensor provided on the panel 114. In Figure 14, the temperature sensor 171 is mounted at a position corresponding to approximately the center of the screen of the panel 114 and measures the surface temperature of the panel 114. Note that the temperature sensor 171 is not limited to the position corresponding to approximately the center of the screen and may be mounted at other positions.

[0088] Figure 15 shows an example of the configuration of multiple temperature sensors provided on the panel section 114. In Figure 15, the entire screen area of ​​the panel section 114 is divided into 4x9 regions of the same size in the vertical and horizontal directions, and a temperature sensor 171 is attached to each divided region. For the sake of explanation, dashed lines indicating the boundaries of the divided regions are drawn on the screen of the panel section 114.

[0089] In Figure 15, the numbers corresponding to the vertical and horizontal directions of divided region A are written in the upper left divided region A11 and the lower right divided region Aij on the screen of the panel unit 114. In addition, the numbers corresponding to the vertical and horizontal directions of the temperature sensor 171 are written in the upper left temperature sensor 171-11 and the lower right temperature sensor 171-ij.

[0090] However, in these notations, i represents the vertical number and j represents the horizontal number. In other words, although Figure 15 shows an example in which the screen of the panel unit 114 is divided into 4 x 9 division areas, it is possible to divide it into i x j (i, j: integers of 1 or more) division areas A, and the number of division areas A to which the temperature sensor 171 is attached is arbitrary.

[0091] In Figure 15, the temperature sensor 171-11 measures the surface temperature of the divided region A11 on the screen of the panel section 114. Although this is repetitive and will not be explained further, other temperature sensors 171-ij also similarly measure the surface temperature of the divided region Aij corresponding to their mounting position.

[0092] The temperature sensor 171 in Figure 14 and the temperature sensors 171-11 to 171-ij in Figure 15 correspond to the panel temperature measurement unit 151 in Figure 7. When multiple temperature sensors 171-11 to 171-ij are installed, it is possible to measure the surface temperature more accurately compared to when only one temperature sensor 171 is installed.

[0093] The surface temperature measured by the temperature sensor 171 in Figure 14, or the temperature sensors 171-11 to 171-ij in Figure 15, is supplied to the voltage control unit 136 as temperature information. The voltage control unit 136 controls the panel drive voltage based on the temperature information supplied from the temperature sensor 171 in Figure 14, etc.

[0094] (Measurement of panel current) Furthermore, in the display device 1, accuracy can be improved not only by predicting the video load through signal processing performed by the signal processing unit 111, but also by measuring the amount of current corresponding to the panel drive voltage applied to the panel unit 114 using a current sensor or the like.

[0095] If one current sensor is provided for the panel section 114, the current sensor may be mounted on the power supply board that generates the panel drive voltage, or it may be mounted on the panel section 114 itself.

[0096] When multiple current sensors are provided on the panel section 114, the load on each pixel can be measured more accurately by providing them on the drive transistors that drive the pixels, including the OLED elements. Figure 16 shows an example of the configuration of multiple current sensors provided on the panel section 114.

[0097] Figure 16 shows an enlarged view of the circuit configuration of a subpixel that constitutes one of the pixels arranged two-dimensionally on the panel section 114. In Figure 16, the subpixel has an OLED element 191, a driving transistor 192, and a retaining capacitance element 193. The driving transistor 192, which is configured as a TFT (Thin Film Transistor) or the like, is connected between the OLED element 191 and the driving circuit (not shown). The driving transistor 192 supplies a current Ids corresponding to the voltage from the driving circuit to the OLED element 191, causing the OLED element 191 to emit light at a luminescence brightness corresponding to the current Ids.

[0098] In Figure 16, a current sensor 181 is connected between the drive transistor 192 and the drive circuit. The current sensor 181 measures the current Ids supplied to the OLED element 191.

[0099] The current sensor 181 in Figure 16 corresponds to the panel current measurement unit 152 in Figure 7. The current measured by the current sensor 181 in Figure 16 is supplied to the voltage control unit 136 as current information. The voltage control unit 136 controls the panel drive voltage based on the current information supplied from the current sensor 181 and other sources in Figure 16.

[0100] (Adaptive voltage control) Figure 17 is a flowchart illustrating the flow of the panel drive voltage control process performed by the signal processing unit 111.

[0101] In step S11, the voltage control unit 136 acquires at least one of the following pieces of information: hue information, saturation information, brightness information, APL information, temperature information, and current information.

[0102] Here, hue information, saturation information, and brightness information are information related to the color of the image displayed on the panel unit 114. APL information is information related to the brightness of the screen of the panel unit 114. Temperature information and current information are information measured as physical quantities related to the panel unit 114.

[0103] In step S12, the voltage control unit 136 adaptively controls the panel drive voltage according to the load and application based on the acquired information.

[0104] Applications include achieving high brightness of the screen of the panel unit 114, suppressing temperature rise in the panel unit 114, or achieving low power consumption of the panel unit 114.

[0105] For example, when achieving high brightness, the voltage control unit 136 detects, based on the acquired information, that the APL value is lower than the reference value, the light-emitting area of ​​the panel unit 114 is smaller, and the video signal has as few color components as possible compared to the reference value, and the signal level of the video signal is higher than the reference value, and then controls the panel drive voltage to increase.

[0106] Furthermore, the voltage control unit 136 can also perform control such as measuring the surface temperature and current amount and applying feedback to return the panel drive voltage value to a predetermined state until a constant load is reached, in case the load becomes heavier due to increasing the panel drive voltage.

[0107] For example, to suppress temperature rise, the voltage control unit 136, based on the acquired information, detects when the APL value is higher than the reference value, the light-emitting area is larger, the video signal has as many color components as possible that are higher than the reference value, and the signal level of the video signal is higher than the reference value, and then performs control to reduce the panel drive voltage.

[0108] Furthermore, the voltage control unit 136 can also perform control such as lowering the panel drive voltage to reduce the load, and then, while measuring the surface temperature and current, applying feedback to return the panel drive voltage value to a predetermined state until a constant load is reached.

[0109] In this way, the voltage control unit 136 can adaptively control the panel drive voltage based on the acquired information, while measuring the load, in accordance with objectives such as achieving high brightness, suppressing temperature rise, and reducing power consumption.

[0110] Furthermore, if a less expensive heat dissipation material is used on the back of the panel section 114 for the purpose of cost reduction, the signal processing unit 111 can detect a high-load video signal and, when a temperature rise occurs, control the panel drive voltage to reduce the load and suppress the temperature rise.

[0111] (Specific example configuration) Figure 18 shows a specific example of the configuration of a display device to which this technology is applied.

[0112] The display device 1 shown in Figure 6 can be composed of a set board 211, a power supply board 212, and a T-CON / OLED panel 213.

[0113] The set board 211 comprises a video SoC 231, a power MCU 232, and an I / F unit 233. The video SoC 231 performs video signal processing on the video signal input thereto. The video SoC 231 is a signal processing device having the functions of the signal processing unit 111 shown in Figure 6.

[0114] In other words, the video SoC231 performs HSV control and APL brightness control, and the panel drive voltage is controlled using PWM signals, analog signals, etc., corresponding to these controls. In this example, the PWM signal from the video SoC231 is output to the power supply board 212 via the I / F unit 233 as a panel drive voltage control signal (the signal corresponding to the square wave in frame F11 in the figure).

[0115] The power MCU 232 controls the power supply's on / off state based on signals from the GPIO (General Purpose Input / Output). The power control signal from the power MCU 232 is output to the power supply board 212 via the I / F unit 233 (the signal corresponding to the pulse wave in frame F12 of the diagram).

[0116] The power supply board 212 corresponds to the power supply unit 112 in Figure 6. The power supply board 212 is composed of an LPF 251, a current sensor 252, an I / F unit 253, an I / F unit 254, and an I / F unit 255.

[0117] On the power supply board 212, when a PWM signal is input to the I / F section 253 from the set board 211, the LPF 251 converts the input signal back to an analog signal (waveform in box F13 in the figure). If an analog signal is input from the set board 211, that analog signal can be used as is.

[0118] Then, on the power supply board 212, the panel drive voltage is variably controlled according to the input amplitude and input level based on the analog signal (linear relationship in frame F14 in the figure). The panel drive voltage is applied to the OLED panel of the T-CON / OLED panel 213 via the I / F unit 255. Here, the panel drive voltage may drive the entire screen of the OLED panel, or it may drive predetermined areas such as areas corresponding to the power supply wiring. The panel drive voltage is the voltage for driving the OLED panel (e.g., EVDD voltage).

[0119] The current sensor 252 measures the amount of current of the panel drive voltage applied to the OLED panel of the T-CON / OLED panel 213. The current sensor 252 feeds back the measured amount of current as current information to the video SoC 231 on the set board 211. The current sensor 252 may also be installed on the OLED panel of the T-CON / OLED panel 213 or elsewhere.

[0120] Furthermore, the power supply board 212 switches the power on / off based on the power control signal from the set board 211. Also, the power supply board 212 outputs the T-CON power to the timing controller (T-CON) of the T-CON / OLED panel 213 via the I / F unit 254.

[0121] The T-CON / OLED panel 213 corresponds to the panel drive unit 113 and panel unit 114 in Figure 6. The T-CON / OLED panel 213 is composed of a temperature sensor 271, an I / F unit 272, and an I / F unit 273.

[0122] The OLED panel of the T-CON / OLED panel 213 is driven based on the panel drive voltage applied from the power supply board 212 via the I / F unit 273. The timing controller (T-CON) of the T-CON / OLED panel 213 operates based on the T-CON power supply input from the power supply board 212 via the I / F unit 272.

[0123] The temperature sensor 271 measures the surface temperature of the OLED panel. The temperature sensor 271 feeds back the measured surface temperature as temperature information to the video SoC 231 on the set board 211.

[0124] On the set board 211, the video SoC 231 controls the panel drive voltage based on at least one of the current information from the current sensor 252 and the temperature information from the temperature sensor 271, which are fed back to it.

[0125] (Other configuration examples) Figure 19 shows another example of the signal processing unit 111 in Figure 6.

[0126] Figure 19 shows the detailed configuration of the signal processing unit 111 in the case of the RGB system, which differs from the configuration shown in Figure 7, which shows the detailed configuration in the case of the WRGB system. In the signal processing unit 111 in Figure 19, the same parts as in the signal processing unit 111 in Figure 7 are denoted by the same reference numerals, and their explanations are omitted.

[0127] The signal processing unit 111 in Figure 19 differs from the signal processing unit 111 in Figure 7 in that the W conversion unit 131, which performs W conversion (e.g., WCT (White Color Translation)), has been removed. That is, in the case of the RGB system, since pixels do not contain subpixels W and white conversion is not necessary, in the signal processing unit 111 of Figure 19, the video signal from the signal input unit 110 is directly input to the hue detection unit 132, saturation detection unit 133, and brightness detection unit 134 together with the APL detection unit 135.

[0128] The hue detection unit 132 performs hue detection processing on the video signal input thereto. The saturation detection unit 133 performs saturation detection processing on the video signal input thereto. The brightness detection unit 134 performs brightness detection processing on the video signal input thereto.

[0129] <2. Variant>

[0130] In the above explanation, the signal processing unit 111 was described as a component of the display device 1, but it is also acceptable to consider the signal processing unit 111 as a standalone device and call it a signal processing device.

[0131] In the above explanation, the example given was that the display device 1 is a television receiver, but it is not limited to this and may be any other device such as a display device. Examples of such display devices include medical monitors, broadcast monitors, and digital signage displays.

[0132] Furthermore, the display device 1 may be used as a display unit for PCs (Personal Computers), tablet devices, smartphones, mobile phones, game consoles, head-mounted displays, in-vehicle equipment such as car navigation systems and rear-seat monitors, and wearable devices such as wristwatches and glasses.

[0133] In the above description, an OLED display device having an OLED panel was used as an example of display device 1, but this technology can also be applied to other display devices such as self-emissive display devices having other self-emissive display panels.

[0134] In the above explanation, we showed a case where each pixel arranged two-dimensionally on the panel section 114 (display panel) is composed of four subpixels: white (W), red (R), green (G), and blue (B). However, the colors of the subpixels are not limited to these. For example, in each pixel, a subpixel of another color with the same high visual sensitivity as white (W) may be used instead of the white (W) subpixel.

[0135] Furthermore, the HSV color space is just one example of a color space that quantitatively represents color, and other color spaces may also be used.

[0136] In this specification, "OLED" may be read as "organic EL (Electro Luminescence)." For example, an OLED display device can also be said to be an organic EL display device. Also, since a video is composed of multiple image frames, "video" may be read as "image."

[0137] Furthermore, the embodiments of this technology are not limited to those described above, and various modifications are possible without departing from the spirit of this technology.

[0138] Furthermore, the effects described herein are merely illustrative and not limiting, and other effects may also occur.

[0139] Furthermore, this technology can be configured as follows:

[0140] (1) At least one piece of information is acquired from among the first piece of information relating to the color of the image displayed on the panel, the second piece of information relating to the brightness of the screen of the panel, and the third piece of information measured as a physical quantity relating to the panel. Based on the acquired information, the voltage for driving the panel is adaptively controlled according to the load and application of the panel. Equipped with a signal processing unit Signal processing device. (2) The signal processing unit, based on the acquired information, measures the load on the panel and adaptively controls the voltage according to the application. The signal processing device described in (1) above. (3) The first piece of information includes information about the components of the color space. The signal processing device described in (1) or (2) above. (4) The aforementioned color space includes the HSV color space. The components of the aforementioned color space include hue, saturation, and lightness. The signal processing device described in (3) above. (5) The signal processing unit controls the gain linked to hue, saturation, or brightness to adjust the weight according to the load on the panel. The signal processing device described in (4) above. (6) The second piece of information includes the average pixel level indicating the overall brightness of the panel screen. The signal processing device according to any one of (1) to (5) above. (7) The signal processing unit controls the brightness curve based on the average pixel level and adjusts the weight according to the load on the panel. The signal processing device described in (6) above. (8) The third piece of information includes at least one physical quantity: the surface temperature of the panel and the amount of current corresponding to the voltage applied to the panel. The signal processing device according to any one of (1) to (7) above. (9) The signal processing unit provides feedback control of the load on the panel based on the measurement results of the surface temperature or the current amount. The signal processing device described in (8) above. (10) One or more temperature sensors for measuring the surface temperature are provided on the panel portion. The signal processing apparatus described in (8) or (9) above. (11) The current sensor for measuring the amount of current is provided in one or more places on the power supply board or panel that generates the voltage. The signal processing apparatus described in (8) or (9) above. (12) The aforementioned applications include achieving high brightness of the screen of the panel, suppressing temperature rise in the panel, or achieving low power consumption of the panel. The signal processing device according to any one of (1) to (11) above. (13) When the signal processing unit aims to increase the brightness of the screen of the panel, it detects that the average pixel level value, which indicates the overall brightness of the screen of the panel included in the second information, is lower than the reference value, the light-emitting area of ​​the panel is smaller, and the signal level of the video signal is higher than the reference value, with the color components of the video signal being fewer than the reference value, as indicated by the color space component information included in the first information. In such a state, the signal processing unit increases the voltage. The signal processing device described in (12) above. (14) If increasing the voltage increases the load on the panel, the signal processing unit performs feedback control based on the measurement results of at least one of the physical quantities included in the third information: the surface temperature of the panel and the amount of current corresponding to the voltage applied to the panel, and controls the voltage to return to a predetermined state. The signal processing device described in (13) above. (15) When the signal processing unit aims to suppress temperature rise in the panel, it detects that the average pixel level value, which indicates the overall brightness of the panel screen included in the second information, is higher than the reference value, the light-emitting area of ​​the panel is larger, and the signal level of the video signal is higher than the reference value, as indicated by the color space component information included in the first information. In such a state, the signal processing unit reduces the voltage. The signal processing device described in (12) above. (16) When the signal processing unit determines that lowering the voltage reduces the load on the panel, it performs feedback control based on the measurement results of at least one of the physical quantities included in the third information: the surface temperature of the panel and the amount of current applied to the panel according to the voltage, and controls the voltage to return to a predetermined state. The signal processing device described in (15) above. (17) The panel portion includes an OLED panel. The signal processing device according to any one of (1) to (16) above. (18) The signal processing unit At least one piece of information is acquired from among the first piece of information relating to the color of the image displayed on the panel, the second piece of information relating to the brightness of the screen of the panel, and the third piece of information measured as a physical quantity relating to the panel. Based on the acquired information, the voltage for driving the panel is adaptively controlled according to the load and application of the panel. Signal processing method. (19) A signal processing unit that processes video signals, A panel unit that displays an image corresponding to the aforementioned video signal. Equipped with, The signal processing unit, At least one piece of information is acquired from among the first piece of information relating to the color of the image displayed on the panel, the second piece of information relating to the brightness of the screen of the panel, and the third piece of information measured as a physical quantity relating to the panel. Based on the acquired information, the voltage for driving the panel is adaptively controlled according to the load and application of the panel. Display device. (20) The panel portion includes an OLED panel. The display device described in (19) above. [Explanation of Symbols]

[0141] 1 Display device, 110 Signal input unit, 111 Signal processing unit, 112 Power supply unit, 113 Panel drive unit, 114 Panel unit, 131 W conversion unit, 132 Hue detection unit, 133 Saturation detection unit, 134 Brightness detection unit, 135 APL detection unit, 136 Voltage control unit, 151 Panel temperature measurement unit, 152 Panel current measurement unit, 171 Temperature sensor, 181 Current sensor, 191 OLED element, 192 Drive transistor, 193 Holding capacitance element, 211 Set board, 212 Power supply board, 213 T-CON / OLED panel, 231 Video SoC, 232 Power MCU, 233 I / F unit, 251 LPF, 252 Current sensor, 253, 254, 255 I / F unit, 271 Temperature sensor, 272, 273 I / F section

Claims

1. First information is obtained, which includes information about the HSV color space components of the video signal corresponding to the image displayed on a panel section in which pixels including self-emissive elements are arranged in two dimensions, and second information is obtained, which includes the average pixel level indicating the brightness of the entire screen of the panel section. Based on the acquired first and second information, the voltage for driving the panel is controlled. Equipped with a signal processing unit, The signal processing unit increases the voltage when it detects, based on the second information, that the average pixel level is lower than the first reference value, that the light-emitting area of ​​the pixels in the panel is relatively small compared to a predetermined area, and that, based on the first information, the luminance component of the video signal, where the load corresponding to the hue component of the HSV color space is lower than the second reference value, is higher than the third reference value. Signal processing device.

2. The signal processing unit, A third piece of information, including the surface temperature of the panel portion, is acquired. Based on the acquired third piece of information, when an increase in the surface temperature of the panel is detected, the voltage is reduced. The signal processing apparatus according to claim 1.

3. One or more temperature sensors for measuring the surface temperature are provided on the panel portion. The signal processing apparatus according to claim 2.

4. The signal processing unit The method involves obtaining first information including information about the HSV color space components of a video signal corresponding to an image displayed on a panel in which pixels, including self-emissive elements, are arranged in a two-dimensional manner, and second information including the average pixel level indicating the overall brightness of the screen of the panel. Based on the acquired second information, when it is detected that the average pixel level value is lower than the first reference value, and further, when it is detected that the light-emitting area of ​​the pixels in the panel is relatively small compared to a predetermined area, and based on the first information, when it is detected that the luminance component of the video signal, for which the load corresponding to the hue component of the HSV color space is lower than the second reference value, is higher than the third reference value, control is performed to increase the voltage for driving the panel. A signal processing method that includes this.

5. A signal processing unit that processes video signals, A panel section that displays an image corresponding to the video signal, with pixels including self-emissive elements arranged in a two-dimensional manner. Equipped with, The signal processing unit, First information including information regarding the HSV color space components of the video signal, and second information including the average pixel level indicating the overall brightness of the panel screen are obtained. Based on the acquired second information, when it is detected that the average pixel level value is lower than the first reference value, and further, when it is detected that the light-emitting area of ​​the pixels in the panel is relatively smaller than a predetermined area, and based on the first information, when it is detected that the luminance component of the video signal, for which the load corresponding to the hue component of the HSV color space is lower than the second reference value, is higher than the third reference value, control is performed to increase the voltage for driving the panel. Display device.

6. First information is obtained, which includes information about the HSV color space components of the video signal corresponding to the image displayed on a panel section in which pixels including self-emissive elements are arranged in two dimensions, and second information is obtained, which includes the average pixel level indicating the brightness of the entire screen of the panel section. Based on the acquired first and second information, the voltage for driving the panel is controlled. Equipped with a signal processing unit, Based on the second information, the signal processing unit detects that the average pixel level is higher than the first reference value, that the light-emitting area of ​​the pixels in the panel is relatively larger than a predetermined area, and that based on the first information, the luminance component of the video signal, where the load corresponding to the hue component of the HSV color space is higher than the second reference value, is higher than the third reference value, and reduces the voltage. Signal processing device.

7. The signal processing unit The method involves obtaining first information including information about the HSV color space components of a video signal corresponding to an image displayed on a panel in which pixels, including self-emissive elements, are arranged in a two-dimensional manner, and second information including the average pixel level indicating the overall brightness of the screen of the panel. Based on the second information, when it is detected that the average pixel level value is higher than the first reference value, and further, when it is detected that the light-emitting area of ​​the pixels in the panel is relatively large compared to a predetermined area, and based on the first information, when it is detected that the luminance component of the video signal, where the load corresponding to the hue component of the HSV color space is higher than the second reference value, is higher than the third reference value, control is performed to reduce the voltage for driving the panel. A signal processing method that includes this.

8. A signal processing unit that processes video signals, A panel section that displays an image corresponding to the video signal, with pixels including self-emissive elements arranged in a two-dimensional manner. Equipped with, The signal processing unit, First information including information regarding the HSV color space components of the video signal, and second information including the average pixel level indicating the overall brightness of the panel screen are obtained. Based on the second information, when it is detected that the average pixel level value is higher than the first reference value, and further, when it is detected that the light-emitting area of ​​the pixels in the panel is relatively larger than a predetermined area, and based on the first information, when it is detected that the luminance component of the video signal, where the load corresponding to the hue component of the HSV color space is higher than the second reference value, is higher than the third reference value, control is performed to reduce the voltage for driving the panel. Display device.

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