Circuit arrangement and display system

Abstract

To provide a circuit arrangement and the like that can achieve proper color correction of respective image data of respective areas on which rays of light from respective light sources are incident.SOLUTION: A circuit arrangement 10 controls a display unit 100 including a first light source 121, a second light source 122, and a display panel 110, and includes an area determination circuit 20 that determines an area to which pixels belong, and a color correction circuit 30 that performs color correction of input image data on the basis of a result of determination of the area. Light from the first light source 121 controlled by a first global light control value GD1 is incident on a first area of the display panel 110, and light from the second light source 122 controlled by a second global light control value GD2 is incident on a second area of the display panel 110. The color correction circuit 30 performs color correction of first image data displayed in the first area, of input image data IMI on the basis of the first global light control value GD1, and performs color correction of second image data displayed in the second area, of the input image data IMI on the basis of the second global light control value GD2.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a circuit device, a display system, and the like.

Background Art

[0002] Patent Document 1 discloses an image display device used in a HUD (Head-Up Display). In this image display device, light of a first video projected from a light source unit through a microlens array is reflected by an enlarging mirror toward the front windshield of the vehicle, so that a virtual image corresponding to the first video is superimposed on the scenery in front of the vehicle and displayed. This virtual image is, for example, an arrow pointing in the traveling direction of the vehicle. Also, light of a second video projected from the light source unit is reflected by a mirror toward the front windshield, and a self-luminous intermediate film provided on the front windshield emits light, so that a real image corresponding to the second video is displayed for the driver. This real image is, for example, a display of the vehicle speed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the image display device of Patent Document 1, since light from a common light source unit is projected using mirrors with different magnification ratios, there is a problem that the luminance on the projection surface differs.

Means for Solving the Problems

[0005] One aspect of the present disclosure relates to a circuit device for controlling a display device including a first light source, a second light source, and a display panel, the circuit device including a region determination circuit for determining a region to which a pixel belongs, and a color correction circuit for performing color correction of input image data based on a determination result of the region. Light from the first light source controlled by a first global dimming value is incident on a first region of the display panel, and light from the second light source controlled by a second global dimming value is incident on a second region of the display panel. The color correction circuit performs color correction of first image data displayed in the first region of the input image data based on the first global dimming value, and performs color correction of second image data displayed in the second region of the input image data based on the second global dimming value.

[0006] Another aspect of the present disclosure relates to a display system including the circuit device described above and the display device.

Brief Description of the Drawings

[0007]

Figure 1

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Modes for Carrying Out the Invention

[0008] Hereinafter, preferred embodiments of the present disclosure will be described in detail. It should be noted that the embodiments described below do not unduly limit the content described in the claims, and not all of the configurations described in these embodiments are essential constituent elements.

[0009] 1. Circuit device, display system FIG. 1 shows a configuration example of a circuit device 10 and a display system 5 including the circuit device 10 according to this embodiment. The circuit device 10 includes a region determination circuit 20 and a color correction circuit 30. The display system 5 includes the circuit device 10 and a display device 100. It should be noted that the circuit device 10 and the display system 5 of this embodiment are not limited to the configuration of FIG. 1, and various modifications such as omitting some of these constituent elements, adding other constituent elements, or replacing some of the constituent elements with other constituent elements are possible. For example, the circuit device 10 may include other circuits such as a light source control circuit, a global dimming value generation circuit, or an interface circuit in addition to the region determination circuit 20 and the color correction circuit 30. Further, the display system 5 may include other devices and circuits such as a processing device.

[0010] The display device 100 displays an image based on image data. The image data can also be referred to as video data, and the display device 100 displays a video based on the video data. The display device 100 is, for example, a head-up display that displays a virtual image in the user's field of view, a cluster display that is a display of a meter panel, a center information display, or an in-vehicle display device such as an electronic mirror. Alternatively, the display device 100 may be a head-mounted display called an HMD, a television device, or a display of an information processing device.

[0011] The display device 100 includes a display panel 110, a first light source 121, and a second light source 122. The display panel 110 is an electro-optical panel such as a liquid crystal display panel or a digital micromirror panel. For example, the display panel 110 is an electro-optical panel having electro-optical elements that modulate incident light from a light source. The first light source 121 and the second light source 122 are realized by light source elements such as LEDs, for example. And the first light source 121 and the second light source 122 are used as the backlight of the display panel 110, for example. The display device 100 may also include a light source driver that drives the first light source 121 and the second light source 122, a display driver that drives the display panel 110, and the like.

[0012] The circuit device 10 is an integrated circuit device in which a plurality of circuit elements are integrated on a semiconductor substrate, for example. The display device 100 displays an image based on the image data IMD output by the circuit device 10. When the display device 100 is a head-up display (HUD), the circuit device 10 is an HUD controller.

[0013] The circuit device 10 includes a region determination circuit 20 and a color correction circuit 30. The region determination circuit 20 determines the region to which a pixel belongs. For example, the region determination circuit 20 determines the region to which each pixel among a plurality of pixels in the input image data IMI belongs. For example, the region determination circuit 20 determines whether each pixel in the input image data IMI belongs to the first region or the second region. This region determination can be made based on the coordinates (X, Y) of the pixel in the input image data IMI, for example. For example, the region determination circuit 20 executes region determination by determining whether the coordinates of the pixel are the coordinates of a pixel in the first region or the second region.

[0014] The color correction circuit 30 performs color correction on the input image data IMI based on the region determination result of the region determination circuit 20. For example, the color correction circuit 30 performs color correction based on the first global dimming value GD1 and the second global dimming value GD2. For example, the color correction circuit 30 performs color correction on the input image data IMI using the first global dimming value GD1 and the second global dimming value GD2 based on the determination result of whether each pixel in the input image data IMI belongs to the first region or the second region. Then, the image data IMD after color correction is output from the circuit device 10 to the display device 100. The color correction can be referred to as brightness correction or brightness adjustment, and the color correction circuit 30 can be referred to as a brightness correction circuit or a brightness adjustment circuit.

[0015] For example, in the present embodiment, light from the first light source 121 controlled by the first global dimming value GD1 is incident on the first region of the display panel 110. Also, light from the second light source 122 controlled by the second global dimming value GD2 is incident on the second region of the display panel 110. The first region and the second region are different regions in the display panel 110, and various shaped regions such as a rectangular region or a circular shape can be assumed. For example, the first region is a region where the first display object group to be displayed on the display panel 110 is displayed, and the second region is a region where the second display object group to be displayed on the display panel 110 is displayed. For example, dimming control of the first light source 121 based on the first global dimming value GD1 and dimming control of the second light source 122 based on the second global dimming value GD2 are performed by a light source control circuit or a light source driver (not shown). This dimming control is a dimming control called global dimming that is performed based on, for example, the detection result of external light. For example, when the external light is bright, global dimming control is performed such as brightening the light of the first light source 121 and the second light source 122, and when the external light is dark, global dimming control is performed such as dimming the light of the first light source 121 and the second light source 122. Note that the number of light sources of the display device 100 is not limited to two, and may be three or more. For example, when a third light source is provided in the display device 100, light from the third light source controlled by the third global dimming value is incident on the third region of the display panel 110.

[0016] Then, the color correction circuit 30 performs color correction on the first image data displayed in the first region of the input image data IMI based on the first global dimming value GD1. Also, the color correction circuit 30 performs color correction on the second image data displayed in the second region of the input image data IMI based on the second global dimming value GD2. For example, the color correction circuit 30 independently performs a first brightness adjustment for adjusting the brightness of the first image in the first region according to the first global dimming value GD1 and a second brightness adjustment for adjusting the brightness of the second image in the second region according to the second global dimming value GD2. For example, the first global dimming value GD1 and the second global dimming value GD2 change according to the detection result of external light and the like, and each dimming value is an independently settable value. Therefore, by the color correction circuit 30 performing color correction on the first image data based on the first global dimming value GD1 and color correction on the second image data based on the second global dimming value GD2, the brightness of the first light source 121 and the second light source 122 changes according to changes in external light and the like, and it becomes possible to perform different brightness adjustments for the first image data in the first region and the image data in the second region. For example, it becomes possible to perform an adjustment so that the brightness becomes substantially the same between the first region and the second region on the projection surface after reflection by the mirror.

[0017] For example, FIG. 2 shows a specific example of the display device 100. In FIG. 2, light from the first light source 121 whose luminance is controlled by the first global dimming value GD1 is incident on the first region RG1 of the display panel 110. Then, the light of the first image (first video) in the first region RG1 is reflected by the first optical system 151 and projected onto the first projection region PR1 of the screen 160. Also, light from the second light source 122 whose luminance is controlled by the second global dimming value GD2 is incident on the second region RG2 of the display panel 110. Then, the light of the second image (second video) in the second region RG2 is reflected by the second optical system 152 and projected onto the second projection region PR2 of the screen 160. In FIG. 2, the first optical system 151 is a first mirror, specifically, for example, a first concave mirror or the like. Also, the second optical system 152 is a second mirror, specifically, for example, a second concave mirror or the like. By using a concave mirror, distortion of the virtual image can be corrected. Also, the concave mirror is an enlarging mirror, and the magnification can be set. The screen 160 is, for example, a transparent screen, specifically, for example, the front windshield of a vehicle or the like.

[0018] FIG. 3 is an example of an image displayed by the screen 160. A first image IM1 is projected and displayed in the first projection region PR1 corresponding to the first region RG1 of the display panel 110, and a second image IM2 is projected and displayed in the second projection region PR2 corresponding to the second region RG2 of the display panel 110. The first image IM1 and the second image IM2 are displayed to a user such as a driver as, for example, a first virtual image and a second virtual image. Also, the object OB is an object in the real world, for example, a vehicle running ahead. The object OB is displayed to the user as a real image by passing through, for example, the transparent screen 160.

[0019] The first image IM1, which is an image of the first image data, includes, for example, an image of characters or an icon. The second image IM2, which is an image of the second image data, includes, for example, an image of AR (Augmented Reality). For example, the first image IM1 includes an image of characters representing various information such as speed (85 km), distance (600 m), or travelable distance (346 km), or an image of an icon representing various information such as direction, sign, or remaining battery level with symbols. An icon can also be called a symbol. The first image IM1 is, for example, a meter display and a display of a measuring instrument. The second image IM2, which is an image of AR, is, for example, an image of digital information added to the real world. For example, the second image IM2 is displayed as additional information of an object OB in the real world. In FIG. 3, the second image IM2 is displayed as an image of an arrow representing the direction of the vehicle, which is the object OB. For example, in an AR display, based on data collected by sensors and in real time, warnings in a navigation or driving assistance system and important information on the road are overlaid and displayed on the scenery actually visible to a user such as a driver. For example, an AR image is displayed in association with an object OB in the scenery. For example, when the object OB is in a state visible to the user or when the appearance of the object OB is expected, the second image IM2 representing the position or direction of the object OB is displayed. In this case, the display position of the second image IM2 changes according to the situation of the real world. On the other hand, the display position of the first image IM1 is fixed, for example, regardless of the situation of the real world.

[0020] Now, when displaying the first image IM1 and the second image IM2 as shown in FIG. 3, in the method of the comparative example of the present embodiment, global dimming using a common global dimming value is performed. For example, in the comparative example, as shown in FIG. 4, global dimming is realized by adjusting the luminance of one light source 124 for global dimming with one global dimming value. However, in this method of the comparative example, it has been found that, for example, in the second image IM2, appropriate dimming is performed so that, for example, the black display part appears to sink darkly, but in the first image IM1, problems such as the luminance of the light source being too bright and the black display part of the background appearing to float white occur.

[0021] For example, in the comparative example, as shown in FIG. 4, since only one light source 124 is provided, the first image IM1 and the second image IM2 cannot perform independent global dimming. For example, if the number of light sources 124 is one and the magnification by the first optical system 151 is different from the magnification by the second optical system 152, a situation occurs where the luminance by the light source 124 is not uniform between the projected image of the first projection area PR1 and the projected image of the second projection area PR2.

[0022] For example, in FIG. 4, the image of the character or icon displayed in the first area RG1 is desirably projected onto the first projection area PR1 as a high-definition image so that the user can appropriately recognize the content of the character or icon. Note that the display of the image can be realized, for example, by modulating the incident light from the light source with the display panel 100 (electro-optical element). On the other hand, the AR image displayed in the second area RG2 is desired to be projected as an image with a larger size than high definition. For this reason, the magnification by the first optical system 151 is lowered and the magnification by the second optical system 152 is increased. The magnification can also be referred to as the projection magnification, for example, the magnification when the image displayed on the display panel 110 is projected onto the screen 160. When the optical system is a concave mirror, the magnification is set by, for example, the curvature and focal length of the concave mirror. By lowering the magnification by the first optical system 151 in this way, the image of the character or icon in the first area RG1 can be projected in high definition and displayed to the user. On the other hand, by increasing the magnification by the second optical system 152, the AR image in the second area RG2 can be displayed in a large size so that the user can appropriately recognize the AR display without missing it.

[0023] On the one hand, the luminance of the projected image increases when the magnification ratio is low and decreases when the magnification ratio is high. For example, the luminance of the projected image attenuates as the projected area increases. Therefore, the image projected onto the first projection area PR1 by the first optical system 151 with a low magnification ratio has a high luminance, and the image projected onto the second projection area PR2 by the second optical system 152 with a high magnification ratio has a low luminance. Thus, in the comparative example of FIG. 4 that uses only one light source 124 and one global dimming value, a situation occurs where the black-displayed portion of the projected image of the first image IM1 in FIG. 3 appears white and floats due to the high luminance. For example, when the luminance of the light source 124 is adjusted according to the AR display of the second image IM2, the luminance of the projected image of the first image IM1 becomes too high.

[0024] In this regard, in the present embodiment, as described with reference to FIGS. 1 and 2, the first light source 121 and the second light source 122 whose luminances are independently controlled are provided, and the first global dimming value GD1 for the first area RG1 and the second global dimming value GD2 for the second area RG2 are prepared. Then, color correction (luminance adjustment) based on the first global dimming value GD1 is performed on the first image in the first area RG1, and color correction (luminance adjustment) based on the first global dimming value GD1 is performed on the second image IM2 in the second area RG2. In this way, for example, when a situation occurs where the black-displayed portion in the first image IM1 becomes whitish as described above, the black-displayed portion in the first image IM1 can also be properly displayed in black, similar to the second image IM2. As a result, in both the first image IM1 and the second image IM2, the black-displayed portion can be properly displayed in black. Also, the display objects other than the black-displayed portion can be adjusted to an appropriate luminance and displayed.

[0025] As described above, in the present embodiment, when light from the first light source 121 is incident on the first region RG1 of the display panel 110 and light from the second light source 122 is incident on the second region RG2 of the display panel 110, the region to which the pixel belongs is determined, and color correction of the input image data IMI is performed based on the determination result of the region. Specifically, color correction of the first image data displayed in the first region RG1 of the input image data IMI is performed based on the first global dimming value GD1. Also, color correction of the second image data displayed in the second region RG2 of the input image data IMI is performed based on the second global dimming value GD2. Then, the input image data IMI after color correction is output to the display device 100 as the image data IMD. In this way, when the first image and the second image are projected by the light of the first light source 121 and the second light source 122 being incident on the first region RG1 and the second region RG2, color correction based on the first global dimming value GD1 is performed on the first image data, and color correction based on the second global dimming value GD2 is performed on the second image data. Therefore, it becomes possible to perform color correction, which is an appropriate brightness adjustment according to the first global dimming value GD1 and the second global dimming value GD2 of the first light source 121 and the second light source 122, on the first image data and the second image data of the input image data IMI. As a result, for example, the black display portion in the projected images of the first image and the second image can be made into an appropriate black display, and the problem that occurred in the comparative example of FIG. 4 can be solved. Also, for example, the display objects other than the black display portion in the projected images of the first image and the second image can be displayed with appropriate brightness.

[0026] The color correction of the first image data based on the first global dimming value GD1 and the color correction of the second image data based on the second global dimming value GD2 are, for example, luminance adjustments that lower the luminance of each of the first image data and the second image data as the luminance of each light source such as the first light source 121 and the second light source 122 increases. The color correction based on the first global dimming value GD1 is performed on all pixel values of the first image data, and the color correction based on the second global dimming value GD2 is performed on all pixel values of the second image data. For example, the color correction can be realized by a process such as multiplying the pixel value (RGB) of the image data by a value corresponding to the reciprocal of the global dimming value.

[0027] For example, in FIGS. 2 and 3, it is assumed that the luminance of the first light source 121 is decreased based on the first global dimming value GD1 so that the black display portion of the first region RG1 does not have a white tint. In this case, since the luminance of the display objects such as characters and icons that are not black display decreases, the color correction circuit 30 performs color correction to increase the pixel value corresponding to the luminance of the display object so that the luminance of the display object approaches the luminance in the original input image data IMI. For the black display portion, since the original luminance is, for example, zero, it is considered that no problem occurs even if such color correction is performed. Also, when the luminance of the light source changes, a situation may occur where the color tone of the display image changes. Therefore, when the luminance of the first light source 121 and the second light source 122 is adjusted based on the first global dimming value GD1 and the second global dimming value GD2, the color correction circuit 30 may perform color correction to suppress the change in the color tone of the display image according to the change in the luminance of the light source on the first image data and the second image data. The color correction of the color correction circuit 30 can be realized by, for example, a conversion table that converts the pixel value (luminance) of each image data in each region of the input image data IMI according to each global dimming value. For example, this conversion table can perform conversion of the pixel value of the image data according to the change in the luminance of the light source and realize color correction for adjusting the color tone of the display image. Also, the conversion characteristics of the conversion table may have the characteristics of a gamma curve.

[0028] Also, as described with reference to FIG. 2, the first region RG1 is a region projected by the first optical system 151, and the second region RG2 is a region projected by the second optical system 152. For example, the first image of the first region RG1 is projected onto the first projection region PR1 of the screen 160 by the first optical system 151, and the first image of the second region RG2 is projected onto the second projection region PR2 of the screen 160 by the second optical system 152. Each of the optical systems of the first optical system 151 and the second optical system 152 can be realized by, for example, a mirror that reflects image light (video light) from each of the first region RG1 and the second region RG2, and specifically can be realized by a concave mirror or the like. In this way, the first image in the first region RG1 onto which the light from the first light source 121 is incident is projected by the first optical system 151, and the second image in the second region RG2 onto which the light from the second light source 122 is incident is projected by the second optical system 152, so that a projected image can be displayed. In this case, there may be differences in optical characteristics such as the magnification of each of the optical systems of the first optical system 151 and the second optical system 152. Due to this difference, a situation may occur in which the luminance in the projected images of the first image and the second image becomes inappropriate luminance. For example, as described above, a situation may occur in which the black display portion becomes whitish. Also in such a case, in the present embodiment, color correction based on the first global dimming value GD1 and the second global dimming value GD2 is performed on the first image data and the second image. Therefore, even when there are differences in optical characteristics such as the magnification of each optical system, it is possible to suppress inappropriate display caused by this difference from occurring due to the luminance adjustment by the color correction.

[0029] Also, in this embodiment, the magnification by the first optical system 151 is lower than the magnification by the second optical system 152, and the first global dimming value GD1 is smaller than the second global dimming value GD2. By doing so, the first image of the first region RG1 is projected at a lower magnification by the first optical system 151, and the second image of the second region RG2 is projected at a higher magnification by the second optical system 152. Thereby, for example, the first image can be displayed with high definition, and the size of the displayed object can be increased for the second image. And since the first global dimming value GD1 is smaller than the second global dimming value GD2, the brightness of the projected image of the first image can be lowered, and it becomes possible to prevent the occurrence of a situation where the black display part becomes whitish as described above.

[0030] Also, as shown in FIG. 2, the first region RG1 and the second region RG2 are projected onto the same screen 160. For example, the light from the first light source 121 and the second light source 122 is incident on the first region RG1 and the second region RG2 of the same display panel 110, and the image light from the first region RG1 and the second region RG2 is projected onto the same screen 160. For example, the first image of the first region RG1 is projected onto the first projection region PR1 of the screen 160, and the second image of the second region RG2 is projected onto the second projection region PR2 of the same screen 160. By doing so, the first image of the first region RG1 by the light from the first light source 121 and the second image of the second region RG2 by the light from the second light source 122 can be projected onto the same screen 160, and the projected images of the first image and the second image can be displayed.

[0031] The first image, which is the image of the first image data, includes an image of characters or icons, and the second image, which is the image of the second image data, includes an AR display image. In this way, the image of the characters or icons of the first image can be projected by the light from the first light source 121, and the AR display image of the second image can be projected by the light from the second light source 122. Therefore, a projection image in which the image of the characters or icons of the first image is projected onto the first projection area PR1 and the projected image of the AR display of the second image is projected by the second projection area PR2 can be displayed. As a result, for example, a projection image suitable for a vehicle HUD or the like can be displayed.

[0032] 2. Configuration example Next, various configuration examples of the circuit device 10 of the present embodiment will be described. FIG. 5 shows a first configuration example of the circuit device 10 of the present embodiment. In the first configuration example of FIG. 5, the first global dimming value GD1 and the second global dimming value GD2 are input from an external processing device 200. For example, the processing device 200 generates the first global dimming value GD1 and the second global dimming value GD2 based on the detection information of the external light from the external light sensor 250, and outputs them to the circuit device 10. For example, the higher the external light, the higher the brightness of the first light source 121 and the second light source 122, and the processing device 200 outputs the first global dimming value GD1 and the second global dimming value GD2. The processing device 200 is, for example, a SoC (System on Chip), and is also called a master device, for example. The processing device 200 can be realized by, for example, a microcomputer, a CPU, or an MPU. For example, the circuit device 10 is communicatively connected to the processing device 200, and the input image data IMI, the first global dimming value GD1, and the second global dimming value GD2 from the processing device 200 are input to the circuit device 10. Then, the color correction circuit 30 of the circuit device 10 performs color correction on the first image data and the second image data displayed in the first region RG1 and the second region RG2 of the input image data IMI based on the respective global dimming values of the first global dimming value GD1 and the second global dimming value GD2 input from the processing device 200. In this way, the color correction circuit 30 can perform color correction on the first image data and the second image data of the input image data IMI based on the first global dimming value GD1 and the second global dimming value GD2 input from the processing device 200. Therefore, when the brightness of each of the first light source 121 and the second light source 122 is controlled based on the first global dimming value GD1 and the second global dimming value GD2 from the processing device 200, it becomes possible to perform appropriate color correction corresponding to the brightness of each light source on the first image data and the second image data.

[0033] Fig. 6 shows a second configuration example of the circuit device 10 of the present embodiment. In the second configuration example of Fig. 6, the circuit device 10 includes a global dimming value generation circuit 40. The global dimming value generation circuit 40 obtains a first global dimming value GD1 and a second global dimming value GD2 based on the global dimming value GD input from the external processing device 200. Note that one of the first global dimming value GD1 and the second global dimming value GD2 may be the same value as the global dimming value GD. For example, the processing device 200 generates the global dimming value GD based on the detection information of the external light from the external light sensor 250 and outputs it to the circuit device 10. For example, the processing device 200 outputs a global dimming value GD that sets the light source to a higher brightness as the external light is brighter. Then, the global dimming value generation circuit 40 generates a first global dimming value GD1 and a second global dimming value GD2 that set the first light source 121 and the second light source 122 to a higher brightness as the external light is brighter, based on the global dimming value GD. Also, when there are differences in optical characteristics such as the magnification of the first optical system 151 and the second optical system 152 in Fig. 2, the global dimming value generation circuit 40 generates a first global dimming value GD1 and a second global dimming value GD2 adjusted according to this difference. For example, when the black display portion of the first image is displayed with a white tint as described in Fig. 3, the global dimming value generation circuit 40 adjusts the first global dimming value GD1 and the second global dimming value GD2 so that the brightness of the first light source 121 is lower than the brightness of the second light source 122. The adjustment value in this case is input from, for example, the processing device 200 and stored in a register section (not shown) of the circuit device 10. By providing such a global dimming value generation circuit 40, the color correction circuit 30 can perform color correction on the first image data and the second image data of the input image data IMI based on the first global dimming value GD1 and the second global dimming value GD2 generated by the global dimming value generation circuit 40 based on the global dimming value GD from the processing device 200. Therefore, for example, it becomes possible to perform appropriate color correction according to the brightness of the first light source 121 and the second light source 122 on the first image data and the second image data.

[0034] Fig. 7 shows a third configuration example of the circuit device 10 of the present embodiment. In the third configuration example of Fig. 7, the circuit device 10 includes a light source control circuit 50. The light source control circuit 50 controls the first light source 121 based on the first global dimming value GD1, and controls the second light source 122 based on the second global dimming value GD2. In this case, the first global dimming value GD1 and the second global dimming value GD2 may be input from an external processing device 200 as shown in Fig. 5, or may be generated by the global dimming value generation circuit 40 as shown in Fig. 6. And the light source control circuit 50 performs control such that, for example, the higher the external light is, the higher the brightness of the first light source 121 and the second light source 122 is set. Also, when there are differences in optical characteristics such as the magnification of the first optical system 151 and the second optical system 152 in Fig. 2, the light source control circuit 50 controls the brightness of the first light source 121 and the second light source 122 according to this difference. For example, when the black display portion of the first image is displayed with a whitish tint in Fig. 3, the light source control circuit 50 controls the light source such that the brightness of the first light source 121 is lower than the brightness of the second light source 122. By providing such a light source control circuit 50, based on the first global dimming value GD1 and the second global dimming value GD2, the first light source 121 and the second light source 122 can be controlled to have appropriate brightness (brightness). Thereby, for example, when there are differences in optical characteristics such as the magnification of the first optical system 151 and the second optical system 152, it becomes possible to set the first light source 121 and the second light source 122 to appropriate brightness according to this difference. Also, according to the second configuration example of Fig. 7, it becomes possible to control the first light source 121 and the second light source 122 without providing a light source control circuit outside the circuit device 10.

[0035] Fig. 8 shows a detailed configuration example of the circuit device 10 of the present embodiment. In the circuit device 10 of Fig. 8, in addition to the region determination circuit 20 and the color correction circuit 30, interface circuits 60 and 62 are further provided. Note that the global dimming value generation circuit 40 and the light source control circuit 50 described in Figs. 6 and 7 may be provided in the circuit device 10 of Fig. 8. Also, in Fig. 8, in addition to the display panel 110, the first light source 121, and the second light source 122, a light source driver 130 and a display driver 140 are further provided in the display device 100.

[0036] The interface circuit 60 is a circuit that performs interface processing with the processing device 200, for example, a host interface circuit. The interface circuit 62 is a circuit that performs interface processing with the light source driver 130. As the interface circuits 60 and 62, for example, a serial interface circuit such as SPI (Serial Peripheral Interface) or I2C (Inter-Integrated Circuit) can be used. For example, when the interface circuits 60 and 62 are SPI serial interface circuits, the interface circuit 60 becomes the slave side, the interface circuit 62 becomes the master side, and between the interface circuit 60 and the interface circuit 62 is a bypass bridge path.

[0037] In FIG. 8, the processing device 200 writes and sets the first global dimming value GD1 and the second global dimming value GD2 in FIG. 5 to a register section (not shown) of the circuit device 10 via the interface circuit 60. In this case, the first global dimming value GD1 and the second global dimming value GD2 are output to the light source driver 130 via the bypass bridge path between the interface circuit 60 and the interface circuit 62. Also, in the case of FIG. 6, the processing device 200 writes and sets the global dimming value GD to the register section of the circuit device 10. Further, the processing device 200 may set adjustment values for generating the first global dimming value GD1 and the second global dimming value GD2 from the global dimming value GD to the register section of the circuit device 10.

[0038] The light source driver 130 of the display device 100 drives the first light source 121 and the second light source 122. In FIG. 8, the light source driver 130 controls the brightness of the first light source 121 and the second light source 122 based on the first global dimming value GD1 and the second global dimming value GD2 input from the interface circuit 62 of the circuit device 10. The display driver 140 receives the image data IMD from the circuit device 10 and drives the display panel 110. For example, the display driver 140 performs driving to display a display image corresponding to the image data IMD on the display panel 110.

[0039] 3. Display System FIG. 9 shows a configuration example of a head-up display 190 as an example of the display system 5 of the present embodiment. The head-up display 190, which is the display system 5 of the present embodiment, includes the circuit device 10 and the display device 100 of the present embodiment. Note that the display system 5 can include a processing device 200. The display device 100 displays a display image based on the data of the output image from the circuit device 10. In the case of the display system 5 of the head-up display 190, the display device 100 projects the display image to display a virtual image to the user. For example, the display device 100 includes a display panel 110 and a backlight 120. The display device 100 can also include a display driver 140 that drives the display panel 110 and a diffusion plate 115 provided between the display panel 110 and the backlight 120. The display device 100 can also include a projection optical system such as a mirror 150 that reflects the projection light of the projection image. For example, the first light source 121 and the second light source 122 are provided as the backlight 120, and the first optical system 151 and the second optical system 152 are provided as the projection optical system.

[0040] The display driver 140 drives the data lines and scanning lines of the display panel 110 to display an image based on the data of the output image from the circuit device 10. The light emitted by the backlight 120 passes through the diffusion plate 115 and the display panel 110, and is reflected by the mirror 150 in the direction of the screen 160. The screen 160 is, for example, a transparent screen, and as an example, it is the windshield of an automobile. The reflecting surface of the screen 160 is, for example, concave, and the projected image appears as a virtual image to the user. That is, the projected image appears to be imaged farther away than the screen 160 as seen from the user. Thereby, the projected image can be displayed in the background.

[0041] Note that the display system 5 of this embodiment is not limited to the configuration of FIG. 9, and various modifications can be made. For example, a display panel other than a liquid crystal display panel may be used as the display panel 110, and the arrangement configurations of the diffusion plate 115 and the projection optical system can also be variously modified. Further, the display system 5 of this embodiment is not limited to the head-up display 190 as shown in FIG. 9, and may be other display systems for automobiles such as a cluster display, or may be a display system other than for automobiles. For example, the display system 5 of this embodiment may be a head-mounted display device or the like.

[0042] As described above, the circuit device of this embodiment is a circuit device that controls a display device including a first light source, a second light source, and a display panel, and includes a region determination circuit that determines a region to which a pixel belongs, and a color correction circuit that performs color correction of input image data based on the determination result of the region. Further, light from the first light source controlled by the first global dimming value is incident on the first region of the display panel, and light from the second light source controlled by the second global dimming value is incident on the second region of the display panel. Then, the color correction circuit performs color correction of the first image data displayed in the first region of the input image data based on the first global dimming value, and performs color correction of the second image data displayed in the second region of the input image data based on the second global dimming value.

[0043] According to this embodiment, when the first image and the second image are projected by the light of the first light source and the second light source being incident on the first region and the second region, color correction based on the first global dimming value is performed on the first image data, and color correction based on the second global dimming value is performed on the second image data. Therefore, appropriate color correction corresponding to the first global dimming value and the second global dimming value of the first light source and the second light source can be performed on the first image data and the second image data of the input image data.

[0044] In this embodiment, the first region may be a region projected by the first optical system, and the second region may be a region projected by the second optical system.

[0045] In this way, the first image in the first region where the light from the first light source is incident is projected by the first optical system, and the second image in the second region where the light from the second light source is incident is projected by the second optical system, so that an image by projection can be displayed.

[0046] In this embodiment, the magnification by the first optical system may be lower than the magnification by the second optical system, and the first global dimming value may be smaller than the second global dimming value.

[0047] In this way, the first image in the first region is projected by the first optical system at a lower magnification, and the second image in the second region is projected by the second optical system at a higher magnification. For example, the first image can be displayed with high definition, and the second image can be displayed so that the size of the displayed object becomes larger.

[0048] In this embodiment, the first region and the second region may be projected onto the same screen.

[0049] In this way, the first image in the first region by the light from the first light source and the second image in the second region by the light from the second light source are projected onto the same single screen, so that the projected images of the first image and the second image can be displayed.

[0050] Also, in this embodiment, the first global dimming value and the second global dimming value may be input from an external processing device.

[0051] In this way, the color correction circuit can perform color correction on the first image data and the second image data of the input image data based on the first global dimming value and the second global dimming value input from the processing device.

[0052] Also, in this embodiment, a global dimming value generation circuit for obtaining the first global dimming value and the second global dimming value based on the global dimming value input from an external processing device may be included.

[0053] In this way, the color correction circuit can perform color correction on the first image data and the second image data of the input image data based on the first global dimming value and the second global dimming value generated based on the global dimming value input from the processing device.

[0054] Also, in this embodiment, a light source control circuit for controlling the first light source based on the first global dimming value and controlling the second light source based on the second global dimming value may be included.

[0055] In this way, the light source control circuit of the circuit device can be used to control the first light source and the second light source to have appropriate brightness based on the first global dimming value and the second global dimming value.

[0056] Also, in this embodiment, the first image which is the image of the first image data may include an image of a character or an icon, and the second image which is the image of the second image data may include an AR display image.

[0057] In this way, the image of the character or icon of the first image can be projected by the light from the first light source, and the AR display image of the second image can be projected by the light from the second light source.

[0058] Also, the display system of this embodiment includes the circuit device and the display device described above.

[0059] Although the present embodiment has been described in detail as above, those skilled in the art will easily understand that many modifications are possible without substantially departing from the novel matters and effects of the present disclosure. Therefore, all such modifications are intended to be included within the scope of the present disclosure. For example, in the specification or drawings, a term described at least once together with a broader or synonymous different term can be replaced with that different term anywhere in the specification or drawings. Also, all combinations of the present embodiment and the modifications are included within the scope of the present disclosure. Further, the configurations and operations of the circuit device, display system, display device, head-up display, etc. are not limited to those described in the present embodiment, and various modified implementations are possible.

Description of Reference Numerals

[0060] 5... Display system, 10... Circuit device, 20... Region determination circuit, 30... Color correction circuit, 40... Global dimming value generation circuit, 50... Light source control circuit, 60, 62... Interface circuit, 100... Display device, 110... Display panel, 115... Diffusion plate, 120... Backlight, 121... First light source, 122... Second light source, 124... Light source, 130... Light source driver, 140... Display driver, 150... Mirror, 151... First optical system, 152... Second optical system, 160... Screen, 190... Head-up display, 200... Processing device, 250... Ambient light sensor, GD... Global dimming value, GD1... First global dimming value, GD2... Second global dimming value, IM1... First image, IM2... Second image, IMD... Image data, IMI... Input image data, OB... Object, PR1... First projection region, PR2... Second projection region, RG1... First region, RG2... Second region

Claims

1. A circuit device for controlling a display device including a first light source, a second light source, and a display panel, an area determination circuit for determining an area to which a pixel belongs, a color correction circuit for performing color correction of input image data based on a determination result of the area, comprising: light from the first light source controlled by a first global dimming value is incident on a first area of the display panel, and light from the second light source controlled by a second global dimming value is incident on a second area of the display panel, the color correction circuit: performs color correction of first image data to be displayed in the first area of the input image data based on the first global dimming value, and performs color correction of second image data to be displayed in the second area of the input image data based on the second global dimming value. A circuit device characterized by this.

2. In the circuit device according to claim 1, the first area is an area projected by a first optical system, and the second area is an area projected by a second optical system. A circuit device characterized by this.

3. In the circuit device according to claim 2, the magnification by the first optical system is lower than the magnification by the second optical system, and the first global dimming value is smaller than the second global dimming value. A circuit device characterized by this.

4. In the circuit device according to claim 1, the first area and the second area are projected on the same screen. A circuit device characterized by this.

5. In the circuit device according to claim 1, the first global dimming value and the second global dimming value are input from an external processing device. A circuit device characterized by this.

6. In the circuit device according to claim 1, including a global dimming value generation circuit for obtaining the first global dimming value and the second global dimming value based on a global dimming value input from an external processing device. A circuit device characterized by this.

7. In the circuit device according to claim 1, including a light source control circuit for controlling the first light source based on the first global dimming value and controlling the second light source based on the second global dimming value. A circuit device characterized by this.

8. In the circuit device according to claim 1, a first image that is an image of the first image data includes an image of a character or an icon, and a second image that is an image of the second image data includes an AR display image. A circuit device characterized by this.

9. A display system, comprising: the circuit device according to any one of claims 1 to 8; and the display device. ​

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