Patent Publication Number: US-2023152586-A1

Title: Image generation device and head-up display

Description:
TECHNICAL FIELD 
     The present disclosure relates to an image generation device and a head-up display including the image generation device. 
     BACKGROUND 
     In the future society of automatic driving, a visual communication between a vehicle and a human being is expected to become increasingly important. For example, a visual communication between a vehicle and a crew in the vehicle is expected to become increasingly important. In this regard, a head-up display (HUD) may be used to implement the visual communication between the vehicle and the crew. The head-up display may implement a so-called augmented reality (AR) by projecting an image or a video on a windshield or a combiner, and superimposing the image on the actual space through the windshield or the combiner to make the image visible to the crew of the vehicle. 
     Patent Document 1 discloses an illumination device used for transmissive illumination of a liquid crystal display device as a head-up display. The illumination device includes a plurality of light sources and a polarization conversion element. The polarization conversion element includes a light transmission member that transmits light, a polarization separation film that transmits p-polarized light and reflects s-polarized light of the light incident on the light transmission member, and a reflective portion that reflects the p-polarized light transmitted through the polarization separation film. 
     PRIOR ART DOCUMENT 
     Patent Document 
     Patent Document 1: Japanese Patent Laid-Open Publication No. 2018-004673 
     SUMMARY OF THE INVENTION 
     Problem to be Solved 
     In the meantime, there is room for improvement in preventing the occurrence of glare in the illumination device disclosed in Patent Document 1. 
     Therefore, the present disclosure is to provide an image generation device capable of preventing the occurrence of glare, and a head-up display including the image generation device. 
     Means to Solve the Problem 
     In order to achieve the goal discussed above, an image generation device according to one aspect of the present disclosure is an image generation device for generating an image for a head-up display. The image generation device includes: a first light source; a second light source disposed to be spaced apart from the first light source by a predetermined distance; a lens that transmits light emitted from the first light source and the second light source; and a display device that forms light that generates the image from the light transmitted through the lens. The lens is constituted by a first region that transmits first light from the first light source, and a second region that transmits second light from the second light source, and a light shielding portion is further provided to prevent the first light from transmitting through the second region and prevents the second light from transmitting through the first region. 
     According to the image generation device having the above configuration including the light shielding portion, it is possible to prevent the glare that can occur due to the light that is emitted from the first light source and transmits the second region, or the light that is emitted from the second light source and transmits the first region. 
     Further, the image generation device according to the present disclosure further includes a holder that holds the lens, and the light shielding portion may be provided in the holder in a state of being disposed between the first light source and the second light source in a space formed between the first and second light sources and the lens. 
     According to the above configuration, since the light shielding portion is provided in the holder, it is possible to reduce the number of parts as compared with a case where the light shielding portion is provided separately from the holder. As a result, the image generation device may be manufactured at a low cost. 
     Further, in the image generation device according to the present disclosure, the light shielding portion may be a protrusion that protrudes toward the first light source and the second light source from a third region formed between the first region and the second region on the incident surface of the lens. 
     According to the above configuration, since the light shielding portion is provided to protrude from the lens, it is possible to reduce the number of parts as compared with a case where the light shielding portion is provided separately from the lens. As a result, the image generation device may be manufactured at a low cost. 
     Further, in the image generation device according to the present disclosure, the light shielding portion may be an emboss-processed surface applied between the first region and the second region on the incident surface of the lens. Alternatively, the light shielding portion may further include an emboss-processed surface applied between the first region and the second region on the incident surface of the lens, separately from the light shielding portion provided in the holder. 
     According to the above configuration, it is possible to reliably prevent the glare by a simple processing. 
     Further, in the image generation device according to the present disclosure, the light shielding portion may include a first reflective surface and a second reflective surface in which the first reflective surface may be disposed at a position where light directed from the first light source toward the second region side is reflected toward the first region in the space formed between the first and second light sources and the lens. The second reflective surface may be disposed at a position where light directed from the second light source toward the first region side is reflected toward the second region in the space. 
     According to the above configuration, it is possible to prevent the occurrence of glare without deteriorating the effective utilization rate of the light emitted from the first light source and the second light source. 
     Further, in the image generation device according to the present disclosure, each of the first region and the second region may be an aspherical lens having an incident surface and an emitting surface both formed as a convex surface. 
     According to the above configuration, the light emitted from the first light source and the second light source may be aberration-corrected by the lens and incident on the display device as parallel light. As a result, the generation precision of the virtual image may be improved. 
     Further, the head-up display according to the present disclosure includes at least one image generation device described above, and at least one reflecting portion that reflects light emitted from the image generation device such that the light is irradiated to a windshield or a combiner. 
     According to the above configuration, a head-up display including the image generation device capable of preventing the occurrence of glare may be provided. 
     Effect of the Invention 
     According to the present disclosure, the image generation device capable of preventing the occurrence of glare, and the head-up display including the image generation device may be provided. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a block diagram of a vehicle system including a head-up display (HUD) according to an embodiment. 
         FIG.  2    is a schematic view illustrating a configuration of the HUD. 
         FIG.  3    is a perspective view illustrating a configuration of an image generation device according to a first embodiment. 
         FIG.  4    is a cross-sectional view taken along line A-A in  FIG.  3   . 
         FIG.  5    is a perspective view illustrating a lens holder of the image generation device in  FIG.  3   . 
         FIG.  6    is a cross-sectional view taken along line B-B in  FIG.  3   . 
         FIG.  7    is a cross-sectional view of an image generation device in a state where a light shielding portion is not provided. 
         FIG.  8    is a cross-sectional view illustrating a configuration of an image generation device according to a second embodiment. 
         FIG.  9    is a perspective view illustrating a lens of the image generation device illustrated in  FIG.  8   . 
         FIG.  10    is a cross-sectional view illustrating a configuration of an image generation device according to a third embodiment. 
         FIG.  11    is a perspective view illustrating a lens of the image generation device illustrated in  FIG.  10   . 
         FIG.  12    is a cross-sectional view illustrating a configuration of an image generation device according to a fourth embodiment. 
         FIG.  13    is a perspective view illustrating a lens holder of the image generation device illustrated in  FIG.  12   . 
     
    
    
     DETAILED DESCRIPTION TO EXECUTE THE INVENTION 
     Hereinafter, embodiments of the present disclosure (hereinafter, referred to as “the embodiment”) will be described with reference to the drawings. Dimensions of members illustrated in the drawings may be different from actual dimensions of the members for convenience of explanation. 
     Further, in the descriptions of the embodiment, the “left-right direction,” the “upward-downward direction,” and the “front-rear direction” may be appropriately stated for convenience of description. Those directions are relative directions set for a head-up display (HUD)  20  illustrated in  FIG.  2   . Here, the “left-right direction” is a direction including the “left direction” and the “right direction.” The “upward-downward direction” is a direction including the “upper direction” and the “downward direction.” The “front-rear direction” is a direction including the “front direction” and the “rear direction.” Although not illustrated in  FIG.  2   , the left-right direction is a direction perpendicular to the upward-downward direction and the front-rear direction. 
     A vehicle system  2  including the HUD  20  according to the embodiment will be described below with reference to  FIG.  1   .  FIG.  1    is a block diagram of the vehicle system  2 . The vehicle  1  on which the vehicle system  2  is mounted is a vehicle (automobile) capable of traveling in an automatic driving mode. 
     As illustrated in  FIG.  1   , the vehicle system  2  includes a vehicle control unit  3 , a sensor  5 , a camera  6 , a radar  7 , a human machine interface (HMI)  8 , a global positioning system (GPS)  9 , a wireless communication unit  10 , and a storage device  11 . Further, the vehicle system  2  includes a steering actuator  12 , a steering device  13 , a brake actuator  14 , a brake device  15 , an accelerator actuator  16 , and an accelerator device  17 . Further, the vehicle system  2  includes the HUD  20 . 
     The vehicle control unit  3  is configured to control traveling of the vehicle  1 . The vehicle control unit  3  is constituted by, for example, at least one electronic control unit (ECU). The electronic control unit includes a computer system (e.g., system on a chip (SoC)) including one or more processors and memories, and an electronic circuit constituted by an active element such as a transistor and a passive element such as a resistor. The processor includes, for example, at least one of a central processing unit (CPU), a micro processing unit (MPU), a graphics processing unit (GPU), and a tensor processing unit (TPU). The CPU may be constituted by a plurality of CPU cores. The GPU may be constituted by a plurality of GPU cores. The memory includes a read only memory (ROM) and a random access memory (RAM). A vehicle control program may be stored in the ROM. For example, the vehicle control program may include an artificial intelligence (AI) program for automatic driving. The AI program is a program (learned model) constructed by supervised or unsupervised machine learning (in particular, deep learning) using multilayer neural networks. In the RAM, a vehicle control program, vehicle control data, and/or surrounding environment information indicating the surrounding environment of the vehicle  1  may be temporarily stored. The processor may be configured to develop the program designated from the various vehicle control programs stored in the ROM on the RAM to execute various processings in cooperation with the RAM. Further, the computer system may be constituted by a non-von Neumann computer such as an application specific integrated circuit (ASIC) or a field-programmable gate array (FPGA). Further, the computer system may be configured by combining a von Neumann computer and a non-von Neumann computer. 
     The sensor  5  includes at least one of an acceleration sensor, a speed sensor, and a gyro sensor. The sensor  5  is configured to detect the traveling state of the vehicle  1 , and output traveling state information to the vehicle control unit  3 . The sensor  5  may further include, for example, a seating sensor that detects whether a driver is sitting on a driver&#39;s seat, a face direction sensor that detects a direction of a driver&#39;s face, an outside weather sensor that detects an outside weather condition, and a person sensing sensor that detects whether a person is in the inside of the vehicle. 
     The camera  6  is, for example, a camera that includes a capture device such as a charge-coupled device (CCD) or a complementary metal-oxide semiconductor (CMOS). The camera  6  includes one or more external cameras  6 A and internal cameras  6 B. 
     The external camera  6 A is configured to acquire image data indicating the surrounding environment of the vehicle  1 , and then send the image data to the vehicle control unit  3 . The vehicle control unit  3  acquires surrounding environment information based on the sent image data. Here, the surrounding environment information may include objects existing outside the vehicle  1  (pedestrians, other vehicles, or signs). For example, the surrounding environment information may include information about the properties of the objects existing outside the vehicle  1 , and information about the distance and position of the objects relative to the vehicle  1 . The external camera  6 A may be configured as a monocular camera, or may be configured as a stereo camera. 
     The internal camera  6 B is disposed inside the vehicle  1 , and is configured to acquire image data indicating an occupant. The internal camera  6 B functions, for example, as an eye tracking camera that tracks a viewpoint E of the occupant (to be described later with reference to  FIG.  2   ). The internal camera  6 B is provided, for example, in the vicinity of a room mirror, or the inside of an instrument panel. 
     The radar  7  includes at least one of a millimeter wave radar, a microwave radar, and a laser radar (e.g., LiDAR unit). For example, the LiDAR unit is configured to detect the surrounding environment of the vehicle  1 . In particular, the LiDAR unit is configured to acquire 3D mapping data (point cloud data) indicating the surrounding environment of the vehicle  1 , and then send the 3D mapping data to the vehicle control unit  3 . The vehicle control unit  3  identifies surrounding environment information based on the sent 3D mapping data. 
     The HMI  8  is constituted by an input unit that receives an input operation from a driver, and an output unit that outputs traveling information to the driver. The input unit includes a steering wheel, an accelerator pedal, a brake pedal, and a driving mode switching switch that switches a driving mode of the vehicle  1 . The output unit is a display that displays various traveling information (excluding HUD). 
     The GPS  9  is configured to acquire current position information of the vehicle  1 , and output the acquired current position information to the vehicle control unit  3 . 
     The wireless communication unit  10  is configured to receive information (e.g., traveling information) about other vehicles around the vehicle  1  from the other vehicles, and send information (e.g., traveling information) about the vehicle  1  to the other vehicles (vehicle-to-vehicle communication). Further, the wireless communication unit  10  is configured to receive infrastructure information from an infrastructure facility such as a signal device or a sign light, and send traveling information of the vehicle  1  to the infrastructure facility (road-to-vehicle communication). Further, the wireless communication unit  10  is configured to receive information about a pedestrian from a portable electronic device (smart phone, tablet, wearable device) carried by the pedestrian, and send own vehicle traveling information of the vehicle  1  to the portable electronic device (pedestrian-to-vehicle communication). The vehicle  1  may directly communicate with other vehicles, the infrastructure facility, or the portable electronic device in an ad-hoc mode, or may communicate with them via an access point. Further, the vehicle  1  may communicate with other vehicles, the infrastructure facility, or the portable electronic device via a communication network (not illustrated). The communication network includes at least one of the internet, a local area network (LAN), a wide area network (WAN), and a radio access network (RAN). A wireless communication standard is, for example, Wi-Fi (registered trademark), Bluetooth (registered trademark), ZigBee (registered trademark), LPWA, DSRC (registered trademark), or Li-Fi. Further, the vehicle  1  may communicate with other vehicles, the infrastructure facility, or the portable electronic device using the fifth generation mobile communication system (5G). 
     The storage device  11  is an external storage device such as a hard disk drive (HDD) or a solid state drive (SSD). The storage device  11  may store two-dimensional or three-dimensional map information and/or the vehicle control program. For example, the three-dimensional map information may be constituted by the 3D mapping data (point cloud data). The storage device  11  is configured to output the map information or the vehicle control program to the vehicle control unit  3  in response to a request from the vehicle control unit  3 . The map information or the vehicle control program may be updated via the wireless communication unit  10  and the communication network. 
     When the vehicle  1  is traveling in an automatic driving mode, the vehicle control unit  3  automatically generates at least one of a steering control signal, an accelerator control signal, or a brake control signal based on the traveling state information, the surrounding environment information, the current position information, or the map information. The steering actuator  12  is configured to receive the steering control signal from the vehicle control unit  3 , and to control the steering device  13  based on the received steering control signal. The brake actuator  14  is configured to receive the brake control signal from the vehicle control unit  3 , and to control the brake device  15  based on the received brake control signal. The accelerator actuator  16  is configured to receive the accelerator control signal from the vehicle control unit  3 , and to control the accelerator device  17  based on the received accelerator control signal. In this manner, the vehicle control unit  3  automatically controls the traveling of the vehicle  1  based on the traveling state information, the surrounding environment information, the current position information, or the map information. That is, the traveling of the vehicle  1  in the automatic driving mode is automatically controlled by the vehicle system  2 . 
     Meanwhile, when the vehicle  1  is traveling in a manual driving mode, the vehicle control unit  3  generates the steering control signal, the accelerator control signal, and the brake control signal according to the manual operation of a driver on the accelerator pedal, the brake pedal, and the steering wheel. In this manner, in the manual driving mode, the steering control signal, the accelerator control signal, and the brake control signal are generated by the manual operation of a driver, and thus, the traveling of the vehicle  1  is controlled by the driver. 
     As described above, the driving mode is constituted by the automatic driving mode and the manual driving mode. The automatic driving mode is constituted by, for example, a fully automatic driving mode, an advanced driving support mode, and a driving support mode. In the fully automatic driving mode, the vehicle system  2  automatically performs all traveling control of the steering control, the brake control, and the accelerator control, and the driver is not in a state where the vehicle  1  can be driven. In the advanced driving support mode, the vehicle system  2  automatically performs all traveling control of the steering control, the brake control, and the accelerator control, and the driver is in a state where the vehicle  1  can be driven, but the driver does not drive the vehicle  1 . In the driving support mode, the vehicle system  2  automatically performs a part of traveling control among the steering control, the brake control, and the accelerator control, and the driver drives the vehicle  1  under the driving support of the vehicle system  2 . Meanwhile, in the manual driving mode, the vehicle system  2  does not automatically perform the traveling control, and the driver drives the vehicle  1  without the driving support of the vehicle system  2 . 
     The HUD  20  is configured to superimpose the predetermined information (hereinafter, referred to as HUD information) on the actual space outside the vehicle  1  (particularly, surrounding environment in front of the vehicle  1 ), and display the HUD information as an image to the occupant of the vehicle  1 . The HUD information displayed by the HUD  20  is, for example, the vehicle traveling information about the traveling of the vehicle  1  and/or the surrounding environment information about the surrounding environment of the vehicle  1  (particularly, information about the objects existing outside the vehicle  1 ). The HUD  20  is an AR display that functions as a visual interface between the vehicle  1  and the occupant. 
     The HUD  20  includes an image generation device (PGU)  24  and a control unit  25 . 
     The image generation device  24  is configured to emit light for generating a predetermined image displayed to the occupant of the vehicle  1 . For example, the image generation device  24  may emit light for generating a changing image that is changed according to the situation of the vehicle  1 . 
     The control unit  25  controls the operation of each part of the HUD  20 . The control unit  25  is connected to the vehicle control unit  3 , and for example, generates a control signal to control the operation of the image generation device  24  based on the vehicle traveling information or the surrounding environment information sent from the vehicle control unit  3 , and sends the generated control signal to the image generation device  24 . A processor such as a CPU and a memory are mounted on the control unit  25 , and the processor executes a computer program read out from the memory, and controls the operation of the image generation device  24 . In the present embodiment, the vehicle control unit  3  and the control unit  25  are provided as separated components, but the vehicle control unit  3  and the control unit  25  may be integrally configured. For example, the vehicle control unit  3  and the control unit  25  may be configured by a single electronic control unit. 
       FIG.  2    is a schematic view of the HUD  20  when viewed from a side surface side of the vehicle  1 . In the HUD  20 , at least a part of the HUD  20  is positioned inside the vehicle  1 . Specifically, the HUD  20  is installed a predetermined location inside the vehicle  1 . For example, the HUD  20  may be disposed inside the dashboard of the vehicle  1 . 
     As illustrated in  FIG.  2   , the HUD  20  includes a HUD body  21 . The HUD body  21  includes a body housing  22  and an emitting window  23 . The emitting window  23  is constituted by a transparent plate that transmits visible light. The HUD body  21  includes the image generation device  24 , a concave mirror  26  (an example of the reflecting portion), and a plane mirror  28  inside the body housing  22 . The control unit  25  of the HUD  20  is accommodated inside the image generation device  24  in the embodiment. 
     The image generation device  24  is installed inside the body housing  22  to emit light upward. The plane mirror  28  is disposed on a light path of light emitted from the image generation device  24 . Specifically, the plane mirror  28  is disposed above the image generation device  24 , and is configured to reflect the light emitted from the image generation device  24  toward the concave mirror  26 . 
     The concave mirror  26  is disposed on the light path of the light emitted from the image generation device  24  and reflected by the plane mirror  28 . Specifically, the concave mirror  26  is disposed on the front side of the image generation device  24  and the plane mirror  28  inside the body housing  22 . The concave mirror  26  is configured to reflect the light emitted from the image generation device  24  toward a windshield  18  (e.g., front window of the vehicle  1 ). The concave mirror  26  has a reflective surface curved concavely to form a predetermined image, and reflects the formed image of the light emitted from the image generation device  24  at a predetermined magnification. The concave mirror  26  may include, for example, a driving mechanism  27 , and may be configured to change the position and direction of the concave mirror  26  based on the control signal sent from the control unit  25 . 
     The light emitted from the image generation device  24  is reflected by the plane mirror  28  and the concave mirror  26 , and then is emitted from the emitting window  23  of the HUD body  21 . The light emitted from the emitting window  23  of the HUD body  21  is irradiated to the windshield  18 . A part of the light irradiated from the emitting window  23  to the windshield  18  is reflected toward the viewpoint E of the occupant. As a result, the occupant recognizes the light emitted from the HUD body  21  as a virtual image (a predetermined image) formed on the front of the windshield  18  at a predetermined distance. In this manner, the image displayed by the HUD  20  is superimposed on the actual space on the front of the vehicle  1  through the windshield  18 , and as a result, the occupant may recognize a virtual image object I formed by a predetermined image as being floated on the road outside the vehicle. 
     Here, the viewpoint E of the occupant may be any one of the viewpoint of the left eye or the viewpoint of the right eye of the occupant. Alternatively, the viewpoint E may be defined as a midpoint of a line connecting the viewpoint of the left eye and the viewpoint of the right eye. The position of the viewpoint E of the occupant is specified, for example, based on image data acquired by the internal camera  6 B. The position of the viewpoint E of the occupant may be updated at a predetermined interval, or may be determined only once when the vehicle  1  is started. 
     When a 2D image (planar image) is formed as the virtual image object I, a predetermined image is projected to be a virtual image at a single distance determined arbitrarily. When a 3D image (stereoscopic image) is formed as the virtual image object I, a plurality of predetermined images that are the same as or different from each other is projected to be respective virtual images at different distances. Further, the distance (distance from the viewpoint E of the occupant to the virtual image) of the virtual image object I may be appropriately adjusted by adjusting the distance from the image generation device  24  to the viewpoint E of the occupant (e.g., adjusting the distance between the image generation device  24  and the concave mirror  26 ). 
     First Embodiment 
     An image generation device  24 A according to a first embodiment will be described with reference to  FIGS.  3  to  7   . 
       FIG.  3    is a perspective view of the image generation device  24 A.  FIG.  4    is a cross-sectional view taken along line A-A in  FIG.  3   . 
     As illustrated in  FIGS.  3  and  4   , the image generation device  24 A includes a light source substrate  110  on which a light source  111  (first light source  111 A and second light source  111 B), a lens  120  disposed above the light source  111 , and a display device  130  disposed above the lens  120 . The image generation device  24 A further includes a lens holder  140  disposed on the light source substrate  110 , a heat sink  150  disposed below the light source substrate  110 , and a PGU housing  160  that accommodates each part provided with the image generation device  24 A. The light source substrate  110 , the lens  120 , the lens holder  140 , and the heat sink  150  are, for example, fixed to the PGU housing  160  via screws  161 . Further, the display device  130  is attached to the upper surface portion of the PGU housing  160 . 
     The light source  111  (first light source  111 A and second light source  111 B) is, for example, a laser light source or an LED light source. The laser light source is, for example, an RGB light source configured to each emit red laser light, green laser light, and blue laser light. The first light source  111 A and the second light source  111 B are disposed on the light source substrate  110  to be spaced apart from each other by a certain distance in the left-right direction. The light source substrate  110  is, for example, a print substrate constituted by an insulator in which a wiring of an electric circuit is printed on the surface or the inside of the plate. 
     The lens  120  is, for example, an aspherical lens having an incident surface  122  on which light from the light source  111  is incident and an emitting surface  123  from which the incident light is emitted, both of which are formed as convex surfaces. The lens  120  is configured to transmit or reflect the light emitted from the light source  111  to be emitted toward the display device  130 . 
     The lens  120  of the first embodiment includes a first region  121 A that transmits first light emitted from the first light source  111 A, and a second region  121 B that transmits second light emitted from the second light source  111 B. The first light source  111 A and the second light source  111 B are disposed in parallel in the left-right direction. The first region  121 A is an aspherical convex lens corresponding to the first light source  111 A. The second region  121 B is an aspherical convex lens corresponding to the second light source  111 B. An incident surface  122 A of the first region  121 A and an incident surface  122 B of the second region  121 B are incident surfaces having a convex shape that slightly bulges downward. An emitting surface  123 A of the first region  121 A and an emitting surface  123 B of the second region  121 B are emitting surfaces having a convex shape that bulges upward. A part of the right side of the first region  121 A disposed on the left side and a part of the left side of the second region  121 B disposed on the right side are coupled to each other. The lens  120  is attached to the lens holder  140  such that the center of the emitting surface of the first light source  111 A becomes a focal point position of the first region  121 A and the center of the emitting surface of the second light source  111 B becomes a focal point position of the second region  121 B. 
     The display device  130  is a liquid crystal display or a digital mirror device (DMD). The display device  130  forms light for generating a predetermined image by the light of the light source  111  that transmits the lens  120 . The display device  130  is attached to the upper surface portion of the PGU housing  160  in a state where the light emitting surface configured to emit light that generates the image is directed upward of the image generation device  24 A. The display device  130  is, for example, attached to the PGU housing  160  from the upper surface side of the PGU housing  160 . A drawing method of the image generation device  24 A may be a raster scan method, a DLP method, or an LCOS method. When the DLP method or the LCOS method is adopted, the light source  111  of the image generation device  24 A may be an LED light source. When a liquid crystal display method is adopted, the light source  111  of the image generation device  24 A may also be a white LED light source. 
     The lens holder  140  holds the lens  120  inside the PGU housing  160  such that the light emitted from the light source  111  is correctly incident with respect to the incident surface  122  of the lens  120 . The detailed configuration of the lens holder  140  will be described later with reference to  FIG.  5   . 
     The heat sink  150  is made of aluminum or copper, which has a high thermal conductivity. The heat sink  150  is provided to be in contact with the back surface of the light source substrate  110  in order to dissipate heat generated from the light source substrate  110 . 
       FIG.  5    is a perspective view of the lens holder  140  viewed from the lens  120  side. As illustrated in  FIG.  5   , the lens holder  140  includes a pair of attaching portions  141  having attaching holes  142  for the screws  161 , and a frame portion  143  provided between the pair of attaching portions  141 . The frame portion  143  is provided with a light shielding portion  144  that is able to shield the light emitted from the light source  111 . The light shielding portion  144  is provided in a central portion of the lens holder  140  in the left-right direction to connect a front side frame portion  143 A and a rear side frame portion  143 B of the lens holder along the front-rear direction. The light shielding portion  144  is formed integrally with the lens holder  140 . 
     The light shielding portion  144  has a rectangular shape in a cross-sectional view (see  FIG.  4   ). The light shielding portion  144  is provided to be disposed between the first light source  111 A and the second light source  111 B in a space  170  formed between the first light source  111 A and the second light source  111 B, and the lens  120 . The light shielding portion  144  is able to shield the first light emitted from the first light source  111 A to transmit the second region  121 B of the lens  120 , and is able to shield the second light emitted from the second light source  111 B to transmit the first region  121 A of the lens  120 . The surface of the light shielding portion  144  may be, for example, painted black so that the light irradiated from each of the light sources  111 A and  111 B may be absorbed without being reflected. 
       FIG.  6    is a cross-sectional view taken along line B-B in  FIG.  3   .  FIG.  6    illustrates a cross-sectional view of the first region  121 A of the lens  120  along the front-rear direction and the upward-downward direction. The cross-sectional view of the second region  121 B of the lens  120  has the same configuration as the cross-sectional view of the first region  121 A illustrated in  FIG.  6   , and thus, detailed description or illustration thereof will be omitted. 
     As illustrated in  FIG.  6   , the first region  121 A of the lens  120  includes an incident portion  127 A constituted by the incident surface  122 A, and a flange portion  126 A provided to be continuous with the incident surface  122 A on the outer periphery of the incident surface  122 A. An outer side surface  126 A 1  of the flange portion  126 A is in contact with an inner side surface  145  of the lens holder  140 . 
     The first region  121 A further includes an upright wall surface  124 A that connects the incident portion  127 A and the emitting surface  123 A. In the example of the lens  120  of the first embodiment, the upright wall surface  124 A is formed at each of the upper outer periphery and the lower outer periphery of the lens  120 . The upright wall surface  124 A is formed so as to spread outward from the center of the lens  120  as it goes from the emitting surface  123 A toward the incident portion  127 A. In other words, the upright wall surface  124 A is formed to be inclined with respect to a direction V perpendicular to the surface of the light source substrate  110  on which the first light source  111 A is mounted (a direction along the center line of the lens). An inclination angle θ of the upright wall surface  124 A is set to be 5 degree or more, or may be 15 degree or more. When the inclination angle θ is less than 5 degree, it is difficult to remove the lens  120  from the mold when the lens  120  is molded. 
     In at least a part of the surrounding of the display device  130 , a light shielding portion  165  that shields light emitted from the first light source  111 A and internally reflected by the upright wall surface  124 A is provided. In the first embodiment, a part of the PGU housing  160  that holds the display device  130  functions as the light shielding portion  165 . The PGU housing  160  is made of, for example, a black resin so as to be able to shield the light emitted from the first light source  111 A. For example, as illustrated by a light path  112 , the light emitted from the first light source  111 A is incident to the inside of the lens  120  from the incident surface  122 A of the lens  120 , and then, is reflected by the upright wall surface  124 A. The light reflected by the upright wall surface  124 A is emitted from the emitting surface  123 A, and then, is irradiated toward the light shielding portion  165  of the PGU housing  160  without being incident on the display device  130 . 
       FIG.  7    is a view illustrating a light path of the light emitted from the first light source  111 A and the second light source  111 B in an image generation device  24 Z including the lens holder  140  that is not provided with the light shielding portion  144 . 
     The light emitted from the first light source  111 A and the second light source  111 B is incident on the incident surfaces  122 A and  122 B of the lens  120 . Since the lens  120  has a shape in which two aspherical convex lenses are coupled in parallel as the same as the image generation device  24 A described above, for example, as illustrated by a first light path  112 A, most of the light emitted from the first light source  111 A is incident on the first region  121 A of the lens  120  and is incident on the display device  130  as light parallel to an optical axis  115 A. In the same manner, for example, as illustrated by a second light path  112 B, most of the light emitted from the second light source  111 B is incident on the second region  121 B, and is incident on the display device  130  as light parallel to an optical axis  115 B. 
     However, since the light shielding portion  144  is not provided in the image generation device  24 Z, for example, as illustrated by a third light path  112 C, a part of the light emitted from the first light source  111 A is incident on the second region  121 B from the incident surface  122 B. As illustrated by the third light path  112 C, the light incident on the incident surface  122 B from the first light source  111 A proceeds in a direction different from the direction of the optical axis  115 A and is incident on the display device  130 . Although the illustration is omitted, in the same manner, light of the light emitted from the second light source  111 B, which is incident on the incident surface  122 A of the first region  121 A proceeds in a direction different from the direction of the optical axis  115 B and is incident on the display device  130 . In this manner, the light incident on the incident surface  122 B of the second region  121 B from the first light source  111 A, or incident on the incident surface  122 A of the first region  121 A from the second light source  111 B is incident on the display device  130  as light that is not parallel to the optical axes  115 A and  115 B, which may cause glare to the driver of the vehicle  1 . 
     With regard to this, the image generation device  24 A according to the first embodiment includes the first light source  111 A, the second light source  111 B disposed to be spaced apart from the first light source  111 A at a certain distance, the lens  120  that transmits the light emitted from the first light source  111 A and the second light source  111 B, the display device  130  that forms the light for generating the image by the light that transmits the lens  120 , and the lens holder  140  that holds the lens  120 . Then, the lens  120  is constituted by the first region  121 A that transmits light emitted from the first light source  111 A (an example of the first light), and the second region  121 B that is coupled in parallel to the first region  121 A and transmits light emitted from the second light source  111 B (an example of the second light). The lens holder  140  is provided with the light shielding portion  144  that is disposed between the first light source  111 A and the second light source  111 B in the space  170  between the first light source  111 A and the second light source  111 B, and the lens  120 , shields the light emitted from the first light source  111 A to transmit the second region  121 B, and shields the light emitted from the second light source  111 B to transmit the first region  121 A. With this configuration, the glare may be suppressed, which may occur by the light from the first light source  111 A that is incident from the incident surface  122 B of the lens  120  and transmits the second region  121 B, or by the light from the second light source  111 B that is Incident from the incident surface  122 A of the lens  120  and transmits the first region  121 A. Further, since the light shielding portion  144  is provided in the lens holder  140 , the number of parts may be reduced as compared with the case where the light shielding portion  144  is provided separately from the lens holder  140 . As a result, the image generation device  24 A may be manufactured at a low cost. 
     Further, according to the image generation device  24 A, the first region  121 A and the second region  121 B of the lens  120  are aspherical lenses having the incident surfaces  122 A and  122 B and the emitting surfaces  123 A and  123 B both formed as a convex surface. As a result, the light emitted from the first light source  111 A and the light emitted from the second light source  111 B may be aberration-corrected by the lens  120  and incident on the display device  130  as parallel light. As a result, the generation precision of the virtual image object I may be improved. 
     Further, in the image generation device  24 A, the lens  120  includes the incident portion  127 A having the incident surface  122 A on which the light from the light source  111 A is incident and the flange portion  126 A provided to be continuous with the incident surface  122 A, the emitting surface  123 A from which the light is emitted, and the upright wall surface  124 A that is the portion connecting the incident portion  127 A and the emitting surface  123 A and having the shape that spreads outward from the center of the lens  120  as it goes from the emitting surface  123 A toward the incident portion  127 A. In at least a part of the surrounding of the display device  130 , the light shielding portion  165  that shields light internally reflected by the upright wall surface  124 A is provided. For example, as indicated by the broken line in  FIG.  6   , when the upright wall surface  124 A is not provided in the lens  120 , the light emitted from the light source  111 A and internally reflected by the portion indicated by the broken line of the lens  120  may become stray light and be incident on the display device  130 . With regard to this, as in the embodiment, in the case where the upright wall surface  124 A that is inclined outward from the emitting surface  123 A toward the incident portion  127 A is provided in the lens  120 , the light emitted from the light source  111 A and internally reflected by the upright wall surface  124 A is irradiated to the light shielding portion  165 , and is shielded by light shielding portion  165 . As a result, the light internally reflected by the upright wall surface  124 A is not incident on the display device  130 . As a result, it is possible to suppress the glare caused by the fact that the light reflected by the upright wall surface  124 A becomes stray light and is incident on the display device  130 . 
     Further, the upright wall surface  124 A is raised from a part of the outer periphery of the incident portion  127 A. That is, the upright wall surface  124 A is provided on the outer periphery of the lens  120  in the front-rear direction, but as illustrated in  FIG.  4   , the upright wall surface  124 A is not provided on the outer periphery of the lens in the left-right direction. As a result, it is possible to suppress the occurrence of glare while maintaining the size of the effective surface of the lens  120 . 
     Further, by making the inclination angle  0  of the upright wall surface  124 A 5 degree or more, it is possible to suppress the occurrence of glare while securing the draft taper of the mold for molding the lens. Further, by making the inclination angle θ of the upright wall surface  124 A 15 degree or more, it is possible to more reliably suppress the occurrence of glare. 
     Further, by the image generation device  24 A, at least a part of the PGU housing  160  is configured to function as the light shielding portion  165 . As a result, it is possible to provide the light shielding portion  165  having a simple configuration, and to suppress the occurrence of glare. 
     Second Embodiment 
     Next, an image generation device  24 B according to a second embodiment will be described with reference to  FIGS.  8  and  9   . The members denoted by the same reference numerals as those the image generation device  24 A according to the first embodiment have the same configuration as that of the image generation device  24 A, and thus, the description thereof will be omitted.  FIG.  8    is a cross-sectional view of the image generation device  24 B.  FIG.  9    is a perspective view of a lens  220  provided with the image generation device  24 B viewed from the light sources  111 A and  111 B sides. 
     As illustrated in  FIGS.  8  and  9   , an incident surface  222  of the lens  220  of the image generation device  24 B is provided with a light shielding portion  225  that is able to shield the light emitted from the light sources  111 A and  111 B. An attaching portion  226  including attaching holes  227  for the screws  161  is provided on both left and right sides of the lens  220 . 
     The light shielding portion  225  is formed by performing an emboss processing on the incident surface  222 . The light shielding portion  225 , which is an emboss-processed surface, is provided in a strip shape in a central portion of the lens  220  in the left-right direction, that is, a predetermined region between an incident surface  222 A of a first region  221 A and an incident surface  222 B of a second region  221 B. The light shielding portion  225  is provided to be spanned a part of the incident surface  222 A and a part of the incident surface  222 B. The light shielding portion  225  faces the upper surface of the light shielding portion  144  provided in the lens holder  140 . For example, the light shielding portion  225  is provided to be slightly wider in both left and right directions than the width of the light shielding portion  144  in the left-right direction. The light shielding portion  225  is able to shield the light emitted from the first light source  111 A to transmit the second region  121 B, and is able to shield the light emitted from the second light source  111 B to transmit the first region  121 A. 
     In this manner, the image generation device  24 B according to the second embodiment further includes the light shielding portion  225  of the lens  220  in addition to the light shielding portion  144  of the lens holder  140 . With this configuration, light that cannot be shielded by the light shielding portion  144 , for example, light such as a fourth light path  112 D illustrated in  FIG.  8    may be shielded by the light shielding portion  225  of the lens  220 . As a result, it is possible to more reliably shield the light from the first light source  111 A to be incident on the second region  121 B from the incident surface  122 B, or the light from the second light source  111 B to be incident on the first region  121 A from the incident surface  122 A, and to further suppress the occurrence of glare. 
     In the image generation device  24 B of the second embodiment, the light shielding portion  144  of the lens holder  140  and the light shielding portion  225  of the lens  220  are provided as the light shielding portions, but the present disclosure is not limited thereto. For example, the light shielding portion  225  of the lens  220  may be provided without providing the light shielding portion  144  of the lens holder  140 . 
     Third Embodiment 
     Next, an image generation device  24 C according to a third embodiment will be described with reference to  FIGS.  10  and  11   . The members denoted by the same reference numerals as those the image generation device  24 A according to the first embodiment have the same configuration as that of the image generation device  24 A, and thus, the description thereof will be omitted.  FIG.  10    is a cross-sectional view of the image generation device  24 C.  FIG.  11    is a perspective view of a lens  320  viewed from the light sources  111 A and  111 B sides. 
     In the image generation device  24 C, the shape of the lens  320  disposed on the light source substrate  110  is different from the lens  120  of the image generation device  24 A according to the first embodiment. Further, a lens holder  340  of the image generation device  24 C is different from the lens  140  of the image generation device  24 A according to the first embodiment in that it does not include a light shielding portion. 
     As illustrated in  FIGS.  10  and  11   , an incident surface  322  of the lens  320  is provided with a light shielding portion  325  that is able to refract light emitted from the light sources  111 A and  111 B and incident on the lens  320 . An attaching portion  326  including attaching holes  327  for the screws  161  is provided on both left and right sides of the lens  320 . 
     The light shielding portion  325  is provided in a central portion of the lens  320  in the left-right direction. The light shielding portion  325  is provided in a third region  321 C formed between a first region  321 A and a second region  321 B. The light shielding portion  325  is provided as a protrusion that protrudes below an incident surface  322 A of the first region  321 A and an incident surface  322 B of the second region  321 B, from the third region  321 C toward the first light source  111 A side and the second light source  111 B side. The light shielding portion  325  is formed integrally with the lens  320  as a part of the lens  320 . 
     The light shielding portion  325  has, for example, a rectangular shape in the cross-sectional view of  FIG.  10   . The light shielding portion  325  extends along the front-rear direction of the lens  320 . The light shielding portion  325  is provided to be disposed between the first light source  111 A and the second light source  111 B in the space  170  formed between the first light source  111 A and the second light source  111 B, and the lens  120 . The light shielding portion  325  transmits the light emitted from the first light source  111 A and transmits the light emitted from the second light source  111 B. 
     In this manner, the image generation device  24 C according to the third embodiment includes the light shielding portion  325  serving as a protrusion that protrudes from the third region  321 C formed between the first region  321 A and the second region  321 B toward the first light source  111 A side and the second light source  111 B side, in the incident surface  322  of the lens  320 . With this configuration, since the light shielding portion  325  is provided as the protrusion that protrudes from the lens  320 , it is possible to refract light emitted from the first light source  111 A and proceeding toward the second region  321 B by the light shielding portion  325  so as not to be incident on the display device  130 , for example, like a fifth light path  112 E illustrated in  FIG.  10   . Although the illustration is omitted, in the same manner, it is possible to refract light emitted from the second light source  111 B and proceeding toward the first region  321 A by the light shielding portion  325  so as not to be incident on the display device  130 . As a result, it is possible to suppress the glare that may be generated by the fact that the light from the first light source  111 A transmits the second region  321 B, or the light from the second light source  111 B transmits the first region  321 A. Further, since the light shielding portion  325  is integrally provided with the lens  320 , the number of parts may be reduced as compared with the case where the light shielding portion  325  is provided separately from the lens  320 . As a result, the image generation device  24 C may be manufactured at a low cost. 
     Fourth Embodiment 
     Next, an image generation device  24 D according to a fourth embodiment will be described with reference to  FIGS.  12  and  13   . The members denoted by the same reference numerals as those the image generation device  24 A according to the first embodiment have the same configuration as that of the image generation device  24 A, and thus, the description thereof will be omitted.  FIG.  12    is a cross-sectional view of the image generation device  24 D.  FIG.  13    is a perspective view of the lens holder  440  provided in the image generation device  24 D viewed from the lens  120  side. 
     In the image generation device  24 D, the configuration of the lens  440  disposed on the light source substrate  110  is different from the lens holder  140  of the image generation device  24 A according to the first embodiment. 
     As illustrated in  FIG.  13   , the lens holder  440  includes a pair of attaching portions  441  having attaching holes  442  for the screws  161 , and a frame portion  443  provided between the pair of attaching portions  441 . The frame  443  is provided with a reflecting portion  444  (an example of a light shielding portion). The reflecting portion  444  is provided in the central portion of the lens holder  440  in the left-right direction to connect a front side frame  443 A and a rear side frame  443 B of the lens holder  440  along the front-rear direction. The reflecting portion  444  is formed integrally with the lens holder  440 . 
     As illustrated in  FIG.  12   , the reflecting portion  444  has a shape that spreads at the end portion to be widened in the left-right direction as it goes downward viewed in a cross-sectional view. That is, the width of a lower surface  444 D of the reflecting portion  444  is larger than the width of an upper surface  444 C of the reflecting portion  444 . The side surfaces of the reflecting portion  444  in the left and right directions constitute a first reflective surface  444 A and a second reflective surface  444 B that is able to reflect the light emitted from the first light source  111 A and the second light source  111 B. The first reflective surface  444 A and the second reflective surface  444 B are formed as reflective surfaces curved concavely. For example, metal such as aluminum is deposited on the first reflective surface  444 A and the second reflective surface  444 B. The reflecting portion  444  is provided to be disposed between the first light source  111 A and the second light source  111 B in the space  170  formed between the first light source  111 A and the second light source  111 B, and the lens  120 . The first reflective surface  444 A reflects the light emitted from the first light source  111 A and directed to the second region  121 B toward the first region  121 A. The second reflective surface  444 B reflects the light emitted from the second light source  111 B and directed to the first region  121 A toward the second region  121 B. 
     In this manner, according to the image generation device  24 D according to the fourth embodiment, the lens holder  440  includes the reflecting portion  444  having the first reflective surface  444 A and the second reflective surface  444 B curved concavely. The first reflective surface  444 A is disposed in the space  170  formed between the first light source  111 A and the second light source  111 B, and the lens  120  at a position where the light directed from the first light source  111 A toward the second region  121 B is reflected toward the first region  121 A. The second reflective surface  444 B is disposed in the space  170  at a position where the light directed from the second light source  111 B toward the first region  121 A is reflected toward the second region  121 B, As a result, for example, as a sixth light path  112 F illustrated in  FIG.  12   , the light emitted from the first light source  111 A and proceeding toward the second region  121 B may be reflected by the first reflective surface  444 A, and may be incident on the display device  130  as light substantially parallel to the optical axis  115 A. In the same manner, for example, as illustrated by a seventh light path  112 G, the light emitted from the second light source  111 B and proceeding toward the first region  121 A may be reflected by the second reflective surface  444 B, and may be incident on the display device  130  as light substantially parallel to the optical axis  115 B. As a result, it is possible to suppress the occurrence of glare without deteriorating the effective utilization rate of the light emitted from the first light source  111 A and the second light source  111 B. 
     Although the embodiments of the present disclosure have been described above, it goes without saying that the technical scope of the present disclosure should not be construed as being limited by the description of the embodiments. It will be appreciated by those skilled in the art that the embodiments are merely examples and various modifications can be made on the embodiments within the scope of the present disclosure described in the claims. The technical scope of the present disclosure should be determined based on the scope of the disclosure described in the claims and the equivalent scope thereof. 
     In the embodiments, it is configured that the light emitted from the image generation device  24  is reflected by the concave mirror  26  and irradiated to the windshield  18 , but the present disclosure is not limited thereto. For example, the light reflected by the concave mirror  26  may be irradiated to the combiner (not illustrated) provided inside the windshield  18 . The combiner is, for example, constituted by a transparent plastic disc. A part of the light irradiated to the combiner from the image generation device  24  of the HUD body  21  is reflected toward the viewpoint E of the occupant as in the case where the light is irradiated to the windshield  18 . 
     Further, in the embodiment, the driving mode of the vehicle has been described as including the fully automatic driving mode, the advanced driving support mode, the driving support mode, and the manual driving mode, but the driving mode of the vehicle is not necessarily limited to those four modes. The driving mode of the vehicle may include at least one of the four modes. For example, the driving mode of the vehicle may be executable any one of the driving modes. 
     Further, the classification of the driving mode of the vehicle or the display form may be appropriately changed in accordance with the laws or regulations related to the automatic driving in each country. Similarly, the definitions of each of “fully automatic driving mode,” “advanced driving support mode,” and “driving support mode” described in the description of the embodiment are merely examples, and these definitions may be appropriately changed in accordance with the laws or regulations related to the automatic driving in each country. 
     This international application claims priority based on Japanese Patent Application No. 2020-078251, filed on Apr. 27, 2020, and the disclosure of Japanese Patent Application No. 2020-078251 is incorporated in this international application in its entire contents by reference. 
     The above descriptions on the specific embodiments of the present disclosure are presented for purposes of illustration. The descriptions are not intended to be exhaustive or to limit the present disclosure to the precise form as described. It will be apparent to those skilled in the art that various modifications and variations are possible in light of the above descriptions. 
     DESCRIPTION OF SYMBOLS 
       1 : vehicle 
       2 : vehicle system 
       3 : vehicle control unit 
       18 : windshield 
       20 : head-up display (HUD) 
       21 : HUD body 
       22 : body housing 
       23 : emitting window 
       24  ( 24 A to  24 D): image generation device 
       25 : control unit 
       26 : concave mirror (example of reflecting portion) 
       110 : light source substrate 
       111 : light source 
       111 A: first light source 
       111 B: second light source 
       120 ,  220 ,  320 : lens 
       121 A: first region 
       121 B: second region 
       122 A,  122 B: incident surface 
       123 A,  123 B: emitting surface 
       124 A,  124 B: upright wall surface 
       130 : display device 
       140 ,  340 ,  440 : lens holder 
       143 ,  443 : frame 
       143 A,  443 A: front frame 
       143 B,  443 B: rear frame 
       144 ,  165 ,  225 ,  325 : light shielding portion 
       150 : heat sink 
       160 : PGU housing 
       170 : space 
       321 A: first region 
       321 B: second region 
       321 C: third region 
       444 : reflecting portion (light shielding portion) 
       444 A: first reflective surface 
       444 B: second reflective surface