Image generation device and image projection device

Abstract

An image generation device (424), which is mounted on a vehicle (1) and generates an image (X), is provided with: a liquid crystal unit (4241); a plurality of light sources (4242) which are divided into a plurality of sections; and a control unit (4243) that performs local dimming control on the lighting / extinguishing of the plurality of light sources (4242) for each section, the control unit (4243) changing the section in the extinguished state in accordance with the viewpoint (E) of an occupant of the vehicle (1).

Description

Technical Field

[0001] The present invention relates to an image generation device and an image projection device. Background Art

[0002] A known head-up display (HUD) is used for visual communication between a vehicle and an occupant of the vehicle. The head-up display projects an image onto a windshield or a combiner, and overlaps the image with the real space through the windshield or the combiner, so that the occupant can visually recognize the image, thereby realizing AR (Augmented Reality).

[0003] Patent Document 1 discloses an image generation device for generating an image of a head-up display. The image generation device includes a light source, a liquid crystal device, an optical element, and an optical member. The liquid crystal device has a rectangular display area and generates an image by using light emitted from the light source. The optical element irradiates the liquid crystal device with the light emitted from the light source. The optical member reduces light corresponding to at least one side of the display area. The liquid crystal device may have a plurality of display areas.

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: International Publication No. 2022 / 019048 Summary of the Invention

[0007] Problems to be Solved by the Invention

[0008] It should be noted that it is known to divide a light source into a plurality of zones and independently control local dimming of the light source corresponding to each zone. Local dimming reduces heat generation and power consumption of the mounted device by reducing the brightness of the light source corresponding to the zone to be dimmed.

[0009] Local dimming is also adopted in a head-up display. In this case, the head-up display can also turn on a part of the plurality of light sources included in the image generation device and turn off another part of the light sources according to each zone. The light controlled in this way is emitted from the image generation device and guided to the occupant's viewing point via the windshield or the combiner of the vehicle. However, the occupant's viewing point of the vehicle is not always located at a predetermined position, and sometimes the light does not reach the occupant's viewing point properly. In addition, the inventors discussed whether the number of light sources to be turned off can be further increased by local dimming.

[0010] An object of the present invention is to provide an image generation device and an image projection device that control a light source according to the viewing point of an occupant of a vehicle.

[0011] Means for Solving the Problems

[0012] The image generation device of the present invention is an image generation device mounted on a vehicle and generating a predetermined image, wherein,

[0013] The image generation device includes:

[0014] A liquid crystal part;

[0015] A plurality of light sources, which are divided into a plurality of partitions; and

[0016] A control part, which performs local dimming control on the lighting and extinguishing of the plurality of light sources for each partition,

[0017] The control part changes the partition set to the extinguished state according to the viewpoint of the occupant of the vehicle.

[0018] The image projection device of the present invention is an image projection device provided in a vehicle and configured to display a predetermined image toward the occupant of the vehicle, wherein,

[0019] The image projection device includes:

[0020] The above-described image generation device; and

[0021] A mirror, which reflects the light emitted from the image generation device.

[0022] Advantages of the Invention

[0023] According to the present invention, it is possible to provide an image generation device and an image projection device that control light sources according to the viewpoint of an occupant of a vehicle. Brief Description of the Drawings

[0024] Figure 1 It is a block diagram of a vehicle system in a vehicle equipped with a head-up display (HUD) of the present invention.

[0025] Figure 2 It is a schematic diagram of the HUD of the present invention.

[0026] Figure 3 It is a block diagram of an image generation unit of the HUD.

[0027] Figure 4 It is a schematic diagram exemplifying the lighting and extinguishing of a plurality of light sources of the image generation unit.

[0028] Figure 5 It is a schematic diagram exemplifying an image visually recognized by an occupant.

[0029] Figure 6 It is a schematic diagram exemplifying the viewpoint of an occupant detected by an in-vehicle camera.

[0030] Figure 7This is a schematic diagram of the local dimming control of the control unit of the image generation unit when the viewpoint of the illustrated occupant is near the center of the eye movement range.

[0031] Figure 8 This is a schematic diagram of the local dimming control of the control unit of the image generation unit after the viewpoint of the occupant moves from Figure 7 this state. Detailed implementation mode

[0032] Hereinafter, embodiments of the present invention (hereinafter referred to as the present embodiment) will be described with reference to the drawings. For ease of explanation, the dimensions of each component shown in the drawings are sometimes different from the actual dimensions of each component.

[0033] In the description of the present embodiment, for ease of explanation, the "left - right direction", "up - down direction", and "front - rear direction" are sometimes appropriately mentioned. These directions are relative directions set for the Figure 2 HUD (Head - Up Display) 42 shown. Here, the "left - right direction" is a direction including the "left direction" and the "right direction". The "up - down direction" is a direction including the "up direction" and the "down direction". The "front - rear direction" is a direction including the "front direction" and the "rear direction". Although the left - right direction is not shown in Figure 2 the figure, the left - right direction is a direction orthogonal to the up - down direction and the front - rear direction. The directions are defined based on the occupant using the HUD42.

[0034] Hereinafter, with reference to Figure 1 the figure, the vehicle system 2 in the vehicle 1 equipped with the head - up display (HUD) 42 according to the present embodiment will be described. Figure 1 This is a block diagram of the vehicle system 2.

[0035] As Figure 1 shown, the vehicle system 2 includes a vehicle control unit 3, a HUD 42, a sensor 5, and a camera 6.

[0036] The vehicle control unit 3 is configured to control the running of the vehicle 1. The vehicle control unit 3 is constituted by, for example, at least one electronic control unit (ECU: Electronic Control Unit). The electronic control unit includes a computer system (for example, SoC (System on a Chip, system on a chip), etc.) including one or more processors and one or more memories, and an electronic circuit constituted by active elements such as transistors and passive elements. The processor includes, for example, at least one of a CPU (Central Processing Unit, central processing unit), an MPU (Micro Processing Unit, micro processing unit), a GPU (Graphics Processing Unit, graphics processing unit), and a TPU (Tensor Processing Unit, tensor processing unit). The CPU may be constituted by multiple CPU cores. The GPU may be constituted by multiple GPU cores. The memory includes a ROM (Read Only Memory, read only memory) and a RAM (Random Access Memory, random access memory). A vehicle control program may be stored in the ROM. For example, the vehicle control program may include an artificial intelligence (AI) program for autonomous driving. The AI program is a program (learning completed model) constructed by supervised or unsupervised machine learning (especially deep learning) using a multi-layer neural network. The vehicle control program, vehicle control data, and / or surrounding environment information representing the surrounding environment of the vehicle may be temporarily stored in the RAM. The processor may be configured to load the program specified by various vehicle control programs stored in the ROM onto the RAM and execute various processes in cooperation with the RAM. In addition, the computer system may be constituted by a non von Neumann type computer such as an ASIC (Application Specific Integrated Circuit, application specific integrated circuit) or an FPGA (Field-Programmable Gate Array, field programmable gate array). Further, the computer system may be constituted by a combination of a von Neumann type computer and a non von Neumann type computer.

[0037] At least a part of the HUD 42 is located inside the vehicle 1. Specifically, the HUD 42 is provided at a predetermined position in the interior of the vehicle 1. For example, the HUD 42 may also be configured within the instrument panel of the vehicle 1. The HUD 42 is a visual interface between the vehicle 1 and the occupant. The HUD 42 is configured to display the HUD information (hereinafter referred to as HUD information) toward the occupant in a manner that overlaps with the real space outside the vehicle 1 (particularly the surrounding environment in front of the vehicle). In this way, the HUD 42 is an AR (Augmented Reality) display. The HUD information displayed by the HUD 42 is, for example, vehicle driving information related to the driving of the vehicle 1 and / or surrounding environment information related to the surrounding environment of the vehicle 1 (particularly information related to an object existing outside the vehicle 1). Details of the HUD 42 will be described later. The HUD 42 is an example of an image projection device.

[0038] In the present embodiment, the vehicle control unit 3 and the control board 425 of the HUD 42 described later are provided as an independent configuration, but the vehicle control unit 3 and the control board 425 may also be integrally formed. In this regard, the control board 425 and the vehicle control unit 3 may also be constituted by a single electronic control unit. The control unit 4243 of the image generation unit 424 of the HUD 42 described later may also be configured as a part of the control board 425.

[0039] The sensor 5 includes at least a vehicle speed sensor that detects the speed of the vehicle 1 and outputs the speed information as a detection result to the vehicle control unit 3. In addition to the vehicle speed sensor, the sensor 5 may also include an acceleration sensor, a gyro sensor, a seating sensor that detects whether the driver is sitting in the driver's seat, a face orientation sensor that detects the face direction of the driver, an external weather sensor that detects the external weather condition, and a human body sensor that detects whether there is someone in the vehicle.

[0040] The camera 6 is, for example, a camera including imaging elements such as a CCD (Charge-Coupled Device) and a CMOS (Complementary Metal-Oxide-Semiconductor). The camera 6 includes one or more external cameras 61 and an internal camera 62. The external camera 61 is configured to output the image data representing the surrounding environment of the vehicle 1 to the vehicle control unit 3 on the basis of acquiring the image data. The vehicle control unit 3 acquires the surrounding environment information based on the transmitted image data. Here, the surrounding environment information may also include information related to objects (pedestrians, other vehicles including the preceding vehicle, signs, etc.) existing outside the vehicle 1. More specifically, the external camera 61 detects the preceding vehicle traveling in front of the vehicle 1 and outputs the image data representing the preceding vehicle to the vehicle control unit 3. The vehicle control unit 3 acquires the surrounding environment information including information related to the preceding vehicle and information related to the distance and position of the preceding vehicle relative to the vehicle 1 based on the transmitted image data. The external camera 61 may be configured as a monocular camera or may be configured as a stereo camera. The external camera 61 is an example of the vehicle detection unit. The surrounding environment information is an example of the preceding vehicle information.

[0041] The internal camera 62 is disposed inside the vehicle 1 and is configured to acquire the image data representing the occupant. The internal camera 62 functions as a tracking camera that tracks the viewpoint E of the occupant. The internal camera 62 may also have a light projection function, an image processing function, and an arithmetic processing function necessary for tracking. Here, the viewpoint E of the occupant is either the viewpoint of the left eye or the viewpoint of the right eye of the occupant. The viewpoint E may also be defined as the midpoint of the line segment connecting the viewpoint of the left eye and the viewpoint of the right eye. In the present embodiment, the viewpoint E of the occupant is set as the viewpoint of the left eye of the occupant. The vehicle control unit 3 may also determine the position of the viewpoint E of the occupant based on the image data acquired by the internal camera 62. The position of the viewpoint E of the occupant is updated at a predetermined cycle based on the image data.

[0042] Next, details of the HUD 42 will be described. Figure 2 It is a schematic diagram of the HUD 42 according to the present embodiment. Figure 2 The viewpoint of the left eye of the occupant is represented as the viewpoint E of the occupant.

[0043] As Figure 2 shown, the HUD 42 includes a HUD main body 420. The HUD main body 420 has a housing 422 and an exit window 423. The exit window 423 is a transparent plate that transmits visible light. The HUD main body 420 has an image generation unit (PGU: Picture Generation Unit) 424, a control substrate 425, a flat mirror 426, a drive mechanism 427, and a concave mirror 428 inside the housing 422.

[0044] The image generation unit 424 is configured to generate a predetermined image. Figure 3 is a block diagram of the image generation unit 424. As Figure 3 shown, the image generation unit 424 includes a liquid crystal unit 4241, a plurality of light sources 4242, and a control unit 4243. The plurality of light sources 4242 are, for example, LED light sources respectively. The liquid crystal unit 4241 is a liquid crystal display in this embodiment. In addition, the liquid crystal unit 4241 can also be composed of a DMD (Digital Mirror Device), etc. The drawing method of the image generation unit 424 can also be the DLP method or the LCOS method. When the liquid crystal unit 4241 is a liquid crystal display, the plurality of light sources 4242 can also be white LED light sources respectively. The image generation unit 424 is an example of an image generation device.

[0045] An image formation surface composed of a large number of pixels is formed in the liquid crystal unit 4241 of the image generation unit 424. The image generation unit 424 is configured to form an image using a part of the image formation surface. Further, the image generation unit 424 is configured to change the display position of the image by changing the positions of the pixels forming the image.

[0046] The control unit 4243 is configured to control the operation of the image generation unit 424. In this embodiment, the plurality of light sources 4242 are divided into a plurality of partitions, and the control unit 4243 is configured to perform local dimming control on the lighting and extinguishing of the plurality of light sources 4242 for each partition. The details of the local dimming control will be described later. The control unit 4243 is composed of an electronic control unit (ECU). The electronic control unit includes a computer system (e.g., SoC, etc.) including one or more processors and one or more memories, and an electronic circuit composed of active elements such as transistors and passive elements. The processor includes at least one of a CPU, an MPU, a GPU, and a TPU. The memory includes a ROM and a RAM. In addition, the computer system can also be composed of a non - von Neumann type computer such as an ASIC or an FPGA.

[0047] Return to Figure 2 , and continue the description of the HUD 42. The control board 425 is configured to control the operations of the image generation unit 424 (control unit 4243) and the drive mechanism 427. The control board 425 is equipped with a processor such as a CPU (Central Processing Unit) and a memory. The processor executes a computer program read from the memory to control the operation of the image generation unit 424. The control board 425 can also be controlled in such a way that the orientation (angle) of the concave mirror 428 is changed via the drive mechanism 427.

[0048] The control substrate 425 acquires the information and image data transmitted from the vehicle control unit 3. The acquired information or image data at least includes the viewpoint information related to the occupant's viewpoint E. The control substrate 425 is further configured to generate a control signal for controlling the operation of the image generation unit 424 based on the information and image data, and transmit the generated control signal to the control unit 4243 of the image generation unit 424. More specifically, the control substrate 425 is configured to control the display position of the image generated by the image generation unit 424 based on the acquired information and image data.

[0049] The concave mirror 428 is disposed on the optical path of the light emitted from the image generation unit 424 and reflected by the plane mirror 426. Specifically, the concave mirror 428 is disposed in the HUD main body 420 on the front side of the image generation unit 424 and the plane mirror 426. The concave mirror 428 is configured to reflect the light emitted from the image generation unit 424 toward the windshield 18 (for example, the front window of the vehicle 1) via the emission window 423. The concave mirror 428 has a concave reflecting surface and reflects the image of the light emitted from the image generation unit 424 and imaged at a predetermined magnification. The plane mirror 426 and the concave mirror 428 are an example of a reflecting mirror.

[0050] The light emitted from the emission window 423 of the HUD main body 420 irradiates the windshield 18. A part of the light irradiated from the HUD main body 420 to the windshield 18 is reflected toward the occupant's viewpoint E. As a result, the occupant recognizes the light (predetermined image) emitted from the HUD main body 420 as a virtual image formed at a predetermined distance in front of the windshield 18. In this way, the image displayed by the HUD 42 overlaps with the real space in front of the vehicle 1 through the windshield 18. As a result, the occupant can visually recognize the virtual image object I formed by the predetermined image floating on the road outside the vehicle.

[0051] In addition, when forming a 2D image (planar image) as the virtual image object I, the predetermined image is projected as a virtual image at an arbitrarily specified single distance. When forming a 3D image (stereoscopic image) as the virtual image object I, a plurality of predetermined images that are the same as or different from each other are respectively projected as virtual images at different distances. In addition, by adjusting the distance from the image generation unit 424 to the occupant's viewpoint E (for example, adjusting the distance between the image generation unit 424 and the concave mirror 428), the distance of the virtual image object I (the distance from the occupant's viewpoint E to the virtual image) can be adjusted. In addition, the HUD main body 420 may not have the plane mirror 426. In this case, the light emitted from the image generation unit 424 is not reflected by the plane mirror 426 but enters the concave mirror 428.

[0052] Next, a plurality of light sources 4242 will be described.

[0053] Figure 4 It is a schematic diagram illustrating the lighting and extinguishing of multiple light sources 4242.

[0054] As Figure 4 shown, the multiple light sources 4242 are divided into multiple partitions S1 to S7. In the present embodiment, the multiple light sources 4242 include LED1, LED2, LED3, LED4, LED5, LED6, and LED7. LED1 is arranged in partition S1. LED2 is arranged in partition S2. LED3 is arranged in partition S3. LED4 is arranged in partition S4. LED5 is arranged in partition S5. LED6 is arranged in partition S6. LED7 is arranged in partition S7. In this way, in the present embodiment, one LED is arranged in each partition.

[0055] The multiple partitions S1 to S7 are arranged along the first direction D1 and the second direction D2. The number of partitions arranged along the first direction D1 is larger than the number of partitions arranged along the second direction D2. In the present embodiment, the number of partitions arranged along the first direction D1 is seven. The number of partitions arranged along the second direction D2 is one. That is, in the present embodiment, the multiple partitions S1 to S7 are arranged in a column along the first direction D1. In Figure 4 it, partition S4 (LED4) is located in the center in the first direction D1, and partitions S1, S2, and S3 (LED1, LED2, and LED3) are arranged on the left, and partitions S5, S6, and S7 (LED5, LED6, and LED7) are arranged on the right.

[0056] In Figure 4 it, the lit LEDs are represented by solid lines and filled colors, and the extinguished LEDs are represented by dashed lines. In Figure 4 it, as an example of lighting and extinguishing the multiple light sources 4242, LED1, LED2, and LED3 are extinguished, and LED4, LED5, LED6, and LED7 are lit.

[0057] Figure 5 It is a schematic diagram illustrating an image visually recognized by an occupant. As Figure 5 shown, the image X is displayed in a part of the image-generable area A which is an area capable of generating a predetermined image. Here, the image X is displayed in the display area DA (the left half part in Figure 5 it) that occupies half of the image-generable area A. The image X may display, for example, the speed information of the vehicle 1. In addition, the image generated by the image generation unit 424 is not limited to speed information.

[0058] In the present embodiment, when LEDs 1 in partition S1 on the left side to LEDs 3 in partition S3 are turned off, and LEDs 4 in partition S4 to LEDs 7 in partition S7 on the right side starting from the center are turned on ( Figure 4 ), an image X is displayed in the display area DA in the left half of the image generation area A, and nothing is displayed in other areas ( Figure 5 ). In this way, the image generation unit 424 is configured to form a single virtual image by the light emitted from the plurality of partitions.

[0059] Next, the in-vehicle camera 62 that tracks the occupant's viewing point E will be described.

[0060] Figure 6 is a schematic diagram of the occupant's viewing point E detected by the in-vehicle camera 62. As Figure 6 shown, the in-vehicle camera 62 is configured to detect the movement of the occupant's viewing point E. The in-vehicle camera 62 is configured to detect the viewing point LE of the occupant's left eye, the viewing point RE of the right eye, and the glabella G that is the midpoint of the line segment connecting these viewing points LE and RE. In the present embodiment, the occupant's viewing point E is defined as the viewing point LE of the occupant's left eye, Figure 6 where the viewing point LE is represented by a solid line, and the viewing point RE and the glabella G are represented by dashed lines.

[0061] The in-vehicle camera 62 divides the eye movement range EB as a detectable area. The eye movement range EB is fixed according to the position where the in-vehicle camera 62 is installed in the vehicle 1. The eye movement range EB is, for example, rectangular in shape. In the present embodiment, the length direction of the eye movement range EB corresponds to the first direction D1 of the plurality of light sources 4242. When the in-vehicle camera 62 detects the viewing point LE of the left eye, the viewing point RE of the right eye, and the glabella G within the eye movement range EB, the in-vehicle camera 62 transmits the eye movement range EB including the viewing point LE, the viewing point RE, and the glabella G as image data to the vehicle control unit 3. The vehicle control unit 3 may also determine the positions of the viewing point LE, the viewing point RE, and the glabella G as coordinates within the eye movement range EB, for example, based on the image data received from the in-vehicle camera 62.

[0062] Next, with reference to Figure 7 and Figure 8 , the operation of the control unit 4243 of the image generation unit 424 will be described.

[0063] Figure 7 Illustrates the lighting and extinguishing states of the plurality of light sources 4242 when the viewing point LE of the occupant's left eye is near the center of the eye movement range EB. Figure 8 is a schematic diagram of the local dimming control of the control unit 4243 after the occupant's viewing point E moves from the Figure 7 state. Figure 8The lighting and extinguishing states of a plurality of light sources 4242 when the viewpoint LE' of the left eye of the exemplary occupant is located to the left of the eye movement range EB.

[0064] Figure 7 An image visually recognized by the occupant when the LED corresponding to one partition is lit and the LEDs of other partitions are extinguished. In addition, in reality, the composite image of the images formed by all partitions is visually recognized by the occupant.

[0065] Specifically, Figure 7 A1 at the left end of represents the image visually recognized by the occupant when the LED1 arranged in the partition S1 is lit and the LEDs2 to LED7 arranged in other partitions S2 to S7 are extinguished. Similarly, from Figure 7 The second A2 from the left end of represents the image visually recognized by the occupant when the LED2 arranged in the partition S2 is lit and the LEDs1, LED3 to LED7 arranged in other partitions S1, S3 to S7 are extinguished. From Figure 7 The third A3 from the left end of represents the image visually recognized by the occupant when the LED3 arranged in the partition S3 is lit and the LEDs1, LED2, LED4 to LED7 arranged in other partitions S1, S2, S4 to S7 are extinguished. From Figure 7 The fourth A4 from the left end of represents the image visually recognized by the occupant when the LED4 arranged in the partition S4 is lit and the LEDs1 to LED3, LED5 to LED7 arranged in other partitions S1 to S3, S5 to S7 are extinguished. From Figure 7 The fifth A5 from the left end of represents the image visually recognized by the occupant when the LED5 arranged in the partition S5 is lit and the LEDs1 to LED4, LED6, LED7 arranged in other partitions S1 to S4, S6, S7 are extinguished. From Figure 7 The sixth A6 from the left end of represents the image visually recognized by the occupant when the LED6 arranged in the partition S6 is lit and the LEDs1 to LED5, LED7 arranged in other partitions S1 to S5, S7 are extinguished. From Figure 7 The seventh A7 from the left end of represents the image visually recognized by the occupant when the LED7 arranged in the partition S7 is lit and the LEDs1 to LED6 arranged in other partitions S1 to S6 are extinguished.

[0066] From Figure 7 The three images from the left end of are images with a dark left half. This indicates that even when the LEDs1 to LED3 in the partitions S1 to S3 are lit, when trying to occupy as Figure 5When the display area DA that forms the left half of the image generation area A forms an image, the light emitted from these LEDs 1 to 3 does not contribute much to the image visually recognized by the occupant. Therefore, when the viewing point LE is near the center in the longitudinal direction of the eye movement range EB, even if the LEDs 1 to 3 in the partitions S1 to S3 are turned off, it is difficult to affect the image visually recognized by the occupant when an image is to be displayed. Figure 5 That is, when the viewing point LE of the occupant is near the center, as long as the LEDs 4 to 7 in the partitions S4 to S7 are turned on, even if the LEDs 1 to 3 in the partitions S1 to S3 are turned off, the occupant can sufficiently visually recognize Figure 5 the image. In this way, within the range where it is difficult to affect the image visually recognized by the occupant, the LEDs in a specific partition are turned off, thereby enabling suppression of the power consumption of the image generation unit 424. The situation of controlling the lighting and extinguishing of the LEDs by such a way of thinking is called local dimming control.

[0067] However, the viewing point LE of the occupant may move within the eye movement range. Therefore, the partitions where it is difficult to affect the image visually recognized by the occupant even when the LEDs are turned off change. Figure 8 A1' to A7' represent the images visually recognized by the occupant when the viewing point LE' of the occupant's left eye moves from near the center in the longitudinal direction of the eye movement range EB to the left when each partition is independently lit. According to Figure 8 , even if the LEDs 1, 2, and 7 in the partitions S1, S2, and S7 are turned off, as long as the LEDs 3 to 6 in the partitions S3 to S6 are turned on, the occupant can sufficiently visually recognize an image such as Figure 5 . In this way, there are partitions that are turned off due to the position of the viewing point LE of the occupant among multiple partitions, and the partitions that become the off state change according to the viewing point LE of the occupant.

[0068] When the viewing point LE of the occupant's left eye is near the center of the eye movement range EB ( Figure 7 ), the number of partitions in the lit state is four. At this time, the positions of the partitions in the lit state are the fourth partition S4, the fifth partition S5, the sixth partition S6, and the seventh partition S7 from the left among the seven partitions arranged in a row. The number of partitions in the lit state is four. At this time, the positions of the partitions in the lit state are the fourth partition S4, the fifth partition S5, the sixth partition S6, and the seventh partition S7 from the left end among the seven partitions arranged in a row.

[0069] When the viewing point LE' of the occupant's left eye is on the left side of the eye movement range EB ( Figure 8)In this case, the number of zones that become the lit state is four. At this time, the positions of the zones that become the lit state are the third zone S3, the fourth zone S4, the fifth zone S5, and the sixth zone S6 from the left end among the seven zones arranged in a row. In this way, when the viewpoint E of the occupant moves, the positions of the zones that become the lit state shift in the direction of the zones arranged in a row (the first direction D1 of the plurality of light sources 4242).

[0070] As described above, in the present embodiment, the zones set to the extinguished state are changed according to the viewpoint E of the vehicle occupant, so the light sources corresponding to the zones to be dimmed are extinguished. As an example of the change of the zones, the positions of the zones that become the lit state are changed. Therefore, even when the viewpoint E of the occupant moves, it is possible to provide the image X while maintaining the brightness before the movement of the viewpoint E relative to the occupant, and to implement an image generation unit that suppresses heat generation and energy consumption. Further, it is possible to implement an image projection device including such an image forming unit.

[0071] In addition, in the above-described embodiment, an example in which an image formed in the display area DA occupying the left half of the image generation area A is formed has been described, but the image is actually formed at an arbitrary position in the image generation area A. In this case, depending on the position where the image is to be formed, the zones that hardly affect the image visually recognized by the occupant are different. The control unit 4243 determines the zones that hardly affect the image visually recognized by the occupant according to the position of the image generation area A of the displayed image, changes the determined zones according to the viewpoint E of the occupant, and extinguishes the LEDs of the zones.

[0072] In the present embodiment, the plurality of zones S1 to S7 are divided along the first direction D1 and the second direction D2, and the number of zones arranged along the first direction D1 is larger than the number of zones arranged along the second direction D2. When the viewpoint E of the occupant moves, the positions of the zones that become the lit state shift in the first direction D1 in which more zones are arranged. In other words, more zones can be set to the extinguished state, so heat generation and energy consumption can be further suppressed.

[0073] The embodiments of the present invention have been described above, but the technical scope of the present invention should not be construed as being limited by the description of the present embodiment. The present embodiment is merely an example, and it is understood by those skilled in the art that various changes in the embodiments can be made within the scope of the invention described in the claims. The technical scope of the present invention should be defined based on the scope of the invention described in the claims and its equivalent scope.

[0074] In the above-described embodiment, one LED is arranged in one partition, but the number of LEDs arranged in one partition is not limited to one. Multiple LEDs may also be arranged in one partition. In this case, the control unit 4243 can collectively control the lighting and extinguishing states of the multiple LEDs for each partition. That is, when multiple LEDs are arranged in one partition, the control unit 4243 controls all the multiple LEDs included in one partition to the lit state or the extinguished state. In addition, each of the multiple light sources 4242 is not limited to an LED light source. For example, each light source is an RGB laser light source configured to emit red laser light, green laser light, and blue laser light as laser light sources, and various color laser light sources may also be arranged in one partition. In such a case, the control unit 4243 can also control all the various color laser light sources arranged in one partition to the lit state or the extinguished state.

[0075] In the above-described embodiment, the number of partitions arranged along the second direction D2 is one, but multiple LEDs 4242 may also be arranged along the second direction D2. The number of partitions arranged along the first direction D1 and the second direction D2 is not limited to seven and two.

[0076] In the above-described embodiment, an image X is displayed in the display area DA that occupies half of one direction of the image generation area A (the left half in Figure 5 ), but the position and range of the display area DA are not limited thereto. For example, the image X may also be displayed in the display area that occupies the other half of one direction of the image generation area A (the right half in Figure 5 ). The image X may also be displayed in the display area that occupies one-third of one direction of the image generation area A. The image X may also be displayed in multiple display areas in the image generation area A.

[0077] In the above-described embodiment, the number of partitions in the lit state is four both before and after the movement of the occupant's viewpoint E, but the number of partitions in the lit state may also change. For example, when it is not necessary to increase the brightness of the edge Xe ( Figure 5 ) of the image X displayed in the display area DA when the occupant's viewpoint E moves, that is, when it is within the allowable range where the darkness of the brightness of the edge Xe relative to the brightness of the image X does not affect the visual recognition of the occupant, sometimes the LEDs of the partitions corresponding to the edge Xe may not be lit. In such a case, although the number of partitions in the lit state is four before the movement of the occupant's viewpoint E, the number of partitions in the lit state may be three after the movement of the occupant's viewpoint E. Thus, when the occupant's viewpoint E moves, the number of partitions in the lit state changes, so that the heat generation and energy consumption of the image generation unit 424 can be further suppressed.

[0078] In the above-described embodiment, although the view point E of the occupant is set as the view point LE of the left eye of the occupant, the view point E of the occupant may also be the view point RE of the right eye of the occupant. In the above-described embodiment, although the view point E of the occupant is defined as a single point (monocular) and described, it is not limited thereto. For example, the view point E of the occupant may also be defined as the glabella G as a synthesis of the view point LE of the left eye and the view point RE of the right eye.

[0079] This application claims priority based on Japanese Application No. 2022-201376 filed on December 16, 2022, and incorporates by reference all of the descriptions recited in the above Japanese application.

Claims

1. An image generation device is provided in a vehicle and generates a predetermined image, wherein, the image generation device includes: a liquid crystal part; a plurality of light sources that are divided into a plurality of partitions; and a control part that performs local dimming control of turning on and off the plurality of light sources for each partition, the control part changes the partition set to the off state according to the view point of an occupant of the vehicle.

2. The image generation device according to claim 1, wherein, When the view point of the occupant moves, the position of the partition that becomes the on state changes.

3. The image generation device according to claim 2, wherein, the partitions are arranged in a first direction and a second direction, the number of partitions arranged in the first direction is larger than the number of partitions arranged in the second direction, when the view point of the occupant moves, the position of the partition that becomes the on state shifts in the first direction.

4. The image generation device according to claim 1, wherein, When the view point of the occupant moves, the number of partitions that become the on state changes.

5. An image projection device is provided in a vehicle and configured to display a predetermined image toward an occupant of the vehicle, wherein, the image projection device includes: the image generation device according to any one of claims 1 to 4; and a mirror that reflects light emitted from the image generation device.

Images