Image irradiation device

Abstract

In this image irradiation device (10), a mirror (40) has: an effective reflection region (42) that controls the reflection of light emitted from an image generation unit (20); and an outer peripheral region (44) that surrounds the effective reflection region (42) over the entire circumference. The outer peripheral region (44) is formed thicker than the effective reflection region (42). As a result, the required rigidity is ensured without significantly increasing the weight of the mirror (40). Furthermore, deformation of the mirror (40) is suppressed, and the optical function of the mirror (40) is maintained. On this basis, the mirror (40) is supported by the first housing (52) or the like in the outer peripheral region (44). Thus, deformation of the effective reflection region (42) is prevented in advance.

Description

Image illumination device Technical Field

[0001] The present invention relates to an image illumination apparatus configured to project a display image generated by an image generation unit as a virtual image onto an image display unit. Background Technology

[0002] An image illumination device for vehicle use is known. The image illumination device is configured to project a virtual image onto an image display unit, such as a light-transmitting panel disposed on the front window (i.e., windshield) or the interior side of the vehicle, when disposed inside the vehicle.

[0003] For example, Patent Document 1 discloses an image illumination device comprising: an image generating unit that generates a display image as a source of a virtual image; a reflector that reflects light emitted from the image generating unit toward an image display unit; and a reflector support member that supports the reflector.

[0004] In the image illumination apparatus described in Patent Document 1, a first reflector and a second reflector are provided as reflectors, which sequentially reflect the emitted light from the image generation unit toward the image display unit.

[0005] Patent Document 2 discloses an image generation unit in an image illumination apparatus that generates a display image as a source of a virtual image. The image generation unit includes a liquid crystal panel and an optical unit for backlighting the liquid crystal panel.

[0006] In the image illumination device described in Patent Document 2, a heat-conducting panel is arranged between the liquid crystal panel and the heat sink supporting the optical unit.

[0007] Patent Document 1: Japanese Patent Application Publication No. 2023-76351

[0008] Patent Document 2: Japanese Patent Application Publication No. 2020-3732 Summary of the Invention

[0009] In the image illumination device described in Patent Document 1, the reflector (specifically the second reflector) has a relatively large reflective surface. If the shape of the reflective surface becomes even larger, the reflector is prone to deformation, making it difficult to ensure the rigidity required to maintain the optical function of the reflector.

[0010] One approach is to increase the rigidity of the mirror by thickening its walls. However, this would increase the weight of the mirror and lengthen the molding time, thus increasing costs.

[0011] Another approach is to strengthen the reflector by assembling frame components rather than increasing its wall thickness. However, this would increase costs or weight due to the increased number of components.

[0012] Furthermore, in an image illumination apparatus, the image generation unit needs to have a high-output optical unit in order to project a bright virtual image onto the image display unit. However, this can lead to the liquid crystal panel overheating.

[0013] As described in Patent Document 2, a heat-conducting panel is considered for placement between the liquid crystal panel and the heat sink. In this case, the heat generated by the liquid crystal panel can be released to the heat sink via the heat-conducting panel, thereby preventing the liquid crystal panel from overheating.

[0014] However, in this case, the cost of the image illumination device increases accordingly because a new heat-conducting panel needs to be installed.

[0015] These same issues may arise in imaging devices other than those used in vehicles.

[0016] This invention relates to an image illumination apparatus configured to project a display image generated by an image generation unit as a virtual image onto an image display unit. One object of this invention is to provide an image illumination apparatus that, even with a large-scale reflector reflecting the emitted light from the image generation unit toward the image display unit, achieves a lightweight and inexpensive structure while ensuring the optical function of the reflector.

[0017] Another object of the present invention is to provide an image illumination apparatus that can generate a bright display image while suppressing the cost of the image illumination apparatus.

[0018] The present invention achieves the first objective mentioned above by improving the structure of the reflector.

[0019] The image illumination apparatus of the present invention is configured to project a display image generated by an image generation unit as a virtual image onto an image display unit. This image illumination apparatus includes: a reflector that reflects light emitted from the image generation unit toward the image display unit; and a reflector support member that supports the reflector. The reflector has: an effective reflection area that controls the reflection of light emitted from the image generation unit; and an outer peripheral area that surrounds the effective reflection area throughout its circumference. The outer peripheral area is formed as a thick wall compared to the effective reflection area, and the reflector is supported by the reflector support member in the outer peripheral area.

[0020] As long as the image illumination device is configured to project a virtual image onto the image display unit, its specific application is not particularly limited. An example of an image illumination device is a head-up display for vehicles.

[0021] The specific structure of the image display unit is not particularly limited as long as it is configured to project a virtual image. For example, the image display unit can be a light-transmitting panel disposed on the windshield or interior of a vehicle.

[0022] In a reflector, the specific boundary locations of the effective reflection area and the outer peripheral area are not particularly defined.

[0023] As long as the outer peripheral region of a mirror is formed as a thick wall compared to the effective reflection region, the specific wall thickness of each mirror is not particularly limited.

[0024] The specific support structure of a mirror is not particularly limited as long as it is supported by a mirror support component in the outer peripheral area.

[0025] Furthermore, the present invention achieves another objective mentioned above by improving the structure of the image generation unit.

[0026] The image illumination apparatus of the present invention is configured to project a display image generated by an image generation unit as a virtual image onto an image display unit. In this image illumination apparatus, the image generation unit includes: a liquid crystal panel; an optical unit that backlights the liquid crystal panel; a panel support member that supports the liquid crystal panel; and a mask member that covers the outer peripheral area of ​​the liquid crystal panel. The optical unit is mounted on a heat sink fixed to the panel support member, and the mask member is composed of a component with a thermal conductivity higher than that of the liquid crystal panel and is fixed to the panel support member in a configuration that contacts the heat sink.

[0027] The mask component is configured to cover the outer peripheral area of ​​the liquid crystal panel. The mask component has an opening, the shape of which is not particularly limited.

[0028] The specific material of the mask component is not particularly limited, as long as it is made of a component with a thermal conductivity higher than that of the LCD panel. The specific contact method between the mask component and the heat sink is not particularly limited.

[0029] The effects of the invention

[0030] The image illumination apparatus of the present invention is configured to project a display image generated by an image generation unit as a virtual image onto an image display unit, and to reflect light emitted from the image generation unit toward the image display unit via a reflector. The reflector has: an effective reflection area that controls the reflection of light emitted from the image generation unit; and an outer peripheral area that surrounds the effective reflection area throughout its circumference. The reflector is formed such that the outer peripheral area is thicker than the effective reflection area, and is supported by a reflector support member in the outer peripheral area. Therefore, the image illumination apparatus of the present invention can achieve the effects described below.

[0031] The outer peripheral region is formed as a thick wall compared to the effective reflection region, thus ensuring the required rigidity without significantly increasing the weight of the mirror. This allows for suppression of mirror deformation and maintenance of the mirror's optical function.

[0032] The reflector is supported by a reflector support structure in the outer peripheral region. Therefore, deformation that would adversely affect the function of the reflector in the effective reflection area can be prevented in advance.

[0033] As described above, the image illumination apparatus of the present invention is configured to project a display image generated by the image generation unit as a virtual image onto the image display unit. According to the present invention, in the image illumination apparatus described above, even if the reflector reflecting the emitted light from the image generation unit toward the image display unit is enlarged, a lightweight and inexpensive structure can be achieved while ensuring the optical function of the reflector.

[0034] The image illumination apparatus of the present invention can be further configured to project a first virtual image as a virtual image in the lower region of the image display section and a second virtual image in the upper region. In this case, the image illumination apparatus has a first reflecting region that reflects the display image that serves as the source of the first virtual image and a second reflecting region that reflects the display image that serves as the source of the second virtual image, which can function as an effective reflecting region of the mirror. Furthermore, the first reflecting region is a region that is narrower in width from left to right than the second reflecting region on the upper side, and the mirror is supported by a mirror support member on the left and right sides of the first reflecting region in the outer peripheral region. In this case, the image illumination apparatus according to the present invention can achieve the following effects.

[0035] As an effective reflection area structure, when the first reflection area is located above the second reflection area and is narrower in width compared to the second reflection area, the left and right sides of the first reflection area in the outer peripheral region easily provide space for the configuration of a structure to support the mirror. Therefore, by effectively utilizing this space, the rigidity of the mirror supported by the mirror support component can be adequately ensured.

[0036] As a reflector structure, the effective reflecting area can be formed with a constant wall thickness, and an annular ribs can be formed around the entire circumference of the effective reflecting area. In this case, it is easier to maintain the optical functions required for a reflector in the effective reflecting area and ensure the rigidity required for a reflector in the outer peripheral area.

[0037] When the reflector is configured as a concave mirror with a rectangular shape, it is not easy to maintain the surface accuracy of the effective reflection area. Therefore, the structure of the present invention is more effective.

[0038] When a reflector is supported in a way that allows it to rotate relative to a reflector support member about an axis extending in the left-right direction, it is difficult to maintain the surface accuracy of the effective reflection area. Therefore, the structure of the present invention is more effective.

[0039] The image illumination apparatus of the present invention includes an image generation unit that generates a display image as a source of a virtual image projected onto an image display unit. Specifically, the image generation unit in the image illumination apparatus includes: a liquid crystal panel; an optical unit that backlights the liquid crystal panel; a panel support member that supports the liquid crystal panel; and a mask member that covers the outer peripheral area of ​​the liquid crystal panel. Therefore, the image illumination apparatus of the present invention can achieve the effects described below.

[0040] The image illumination apparatus, by configuring a mask component, can define the usable area of ​​the liquid crystal panel. Furthermore, even if sunlight enters the internal space of the image illumination apparatus, the mask component's light-blocking function can suppress the temperature rise of the liquid crystal panel to a certain extent.

[0041] Furthermore, in the image illumination apparatus according to the present invention, the heat sink mounting the optical unit is fixed to the panel support member. The mask member is constructed of a component with a thermal conductivity higher than that of the liquid crystal panel and is fixed to the panel support member in a manner that allows it to contact the heat sink. Therefore, the image illumination apparatus according to the present invention can achieve the effects described below.

[0042] Even if the LCD panel heats up due to backlighting from the optical unit or sunlight, heat can be dissipated to the heat sink via a mask component with a higher thermal conductivity than the LCD panel. This effectively suppresses overheating of the LCD panel. Furthermore, it allows for high output from the optical unit while maintaining the functionality of the LCD panel.

[0043] Furthermore, instead of using a dedicated heat-conducting panel, the aforementioned effects can be achieved by using a mask component that defines the area to be used on the liquid crystal panel. Therefore, according to the present invention, a bright virtual image can be generated while reducing the cost of the image illumination device.

[0044] As described above, according to the present invention, in an image illumination apparatus configured to project a display image generated by an image generation unit as a virtual image onto an image display unit, a bright display image can be generated while suppressing the cost of the image illumination apparatus.

[0045] Furthermore, the image illumination device according to the present invention can achieve the following effects when the mask component is fixed relative to the panel support component by riveting.

[0046] According to the present invention, the number of components of the image illumination device can be reduced compared to fixing by means of screws or the like.

[0047] In addition, compared with fixing by means of interlocking, it is less likely to apply excessive load to the liquid crystal panel, and it can prevent the gap between the panel support member and the mask member from being accidentally generated as a cause of vibration of the mask member.

[0048] In the image illumination apparatus of the present invention, the panel support member is made of resin, and when the mask member is fixed to the panel support member by hot riveting, it can be fixed more easily than by cold riveting.

[0049] When the image illumination device of the present invention forms openings at two locations of the mask component, it can achieve the following effects.

[0050] In the structure of the mask component, a beam-like portion is formed between the openings at two locations. This improves the rigidity of the mask component and allows heat generated through the liquid crystal panel to be conducted to the heat sink more efficiently.

[0051] Furthermore, two usage areas are defined on two parts of the LCD panel. This allows two virtual images to be projected onto two parts of the image display unit.

[0052] Furthermore, when the image illumination device has a concave mirror that reflects the emitted light from the image generation unit toward the image display unit, sunlight entering the interior space of the image illumination device is reflected by the concave mirror, thereby easily focusing the light toward the edge of the liquid crystal panel. Therefore, it is particularly effective to suppress the temperature rise of the liquid crystal panel by using the light-shielding function of the mask member arranged to cover the outer peripheral area of ​​the liquid crystal panel. Attached Figure Description

[0053] Figure 1 is a side sectional view showing the image illumination device according to the first embodiment of the present invention mounted on a vehicle.

[0054] Figure 2A is a vector view in direction II of Figure 1.

[0055] Figure 2B is a vector view in direction II of Figure 1.

[0056] Figure 3 is a detailed view of Part III of Figure 1.

[0057] Figure 4 is a cross-sectional view along line IV-IV of Figure 3.

[0058] Figure 5 is a V-direction vector view of the reflector of the image illumination device shown in detail in Figure 4.

[0059] Figure 6A is a vector view in direction II of Figure 1 of the image illumination apparatus according to the first modification of the first embodiment.

[0060] Figure 6B is a vector view in direction II of Figure 1 of the image illumination apparatus according to the first modification of the first embodiment.

[0061] Figure 7 is a V-direction vector view of the reflector of the image illumination device according to the second modification of the first embodiment, as shown in Figure 4.

[0062] Figure 8 is a side sectional view of the image illumination apparatus according to the third variation of the first embodiment.

[0063] Figure 9 is a side sectional view showing the image illumination device according to the second embodiment of the present invention mounted on a vehicle.

[0064] Figure 10 is a view of the X-direction vector of Figure 9.

[0065] Figure 11 is a detailed view of part XI of Figure 9.

[0066] Figure 12 is a cross-sectional view along line XII-XII of Figure 11.

[0067] Figure 13 is a perspective view showing the image generation unit of the image illumination device together with the heat sink.

[0068] Figure 14 is a decomposed oblique view showing the image generation unit.

[0069] Figure 15 is a perspective view showing the image generation unit of the image illumination apparatus according to a modified example of the second embodiment, together with a heat sink. Detailed Implementation

[0070] The first embodiment of the present invention will now be described with reference to the accompanying drawings.

[0071] (First Embodiment)

[0072] Figure 1 is a side sectional view showing the image illumination device 10 according to the first embodiment mounted on a vehicle 100. Figures 2A and 2B are vector views in the II direction of Figure 1.

[0073] In Figures 1, 2A, and 2B, the direction represented by X is the "front" of the image illumination device 10 (which is also the "front" of the vehicle), the direction represented by Y is the "left direction" orthogonal to the "front", and the direction represented by Z is the "up direction". The same applies to the figures other than those in Figures 1, 2A, and 2B.

[0074] As shown in Figures 1, 2A, and 2B, the image illumination device 10 according to this embodiment is a head-up display for vehicle use. The image illumination device 10 is configured to project two virtual images, PIC-A and PIC-B, onto an image display unit 106 located on the inner surface of the front window 102 when it is installed in the interior of a vehicle 100.

[0075] The optical path R shown in Figure 1 is the optical path through which the driver 2 visually perceives the virtual images PIC-A and PIC-B projected by the image illumination device 10 onto the image display unit 106.

[0076] The image display unit 106 is positioned in the lower region of the windshield 102 and in front of the steering wheel 104, forming a horizontally elongated rectangular area. This allows the driver 2 of the vehicle 100 to easily visually perceive the virtual images PIC-A and PIC-B projected onto the image display unit 106.

[0077] As shown in Figures 2A and 2B, the image display unit 106 has a lower region 106A and an upper region 106B. Both the lower region 106A and the upper region 106B are horizontally elongated rectangular regions. The upper edge of the lower region 106A and the lower edge of the upper region 106B partially overlap. The upper region 106B is slightly longer horizontally than the lower region 106A.

[0078] Regarding the two virtual images PIC-A and PIC-B, virtual image PIC-A is projected in the lower region 106A of the image display unit 106, and virtual image PIC-B is projected in the upper region 106B of the image display unit 106.

[0079] Specifically, when the vehicle speed is in the low-to-medium speed range (e.g., below 80 km / h), as shown in Figure 2A, a virtual image PIC-A is projected in the lower region 106A. On the other hand, when the vehicle speed reaches a high-speed range exceeding the low-to-medium speed range, as shown in Figure 2B, a virtual image PIC-B is projected in the upper region 106B. This ensures that when the driver 2 moves their viewpoint from the frontal viewpoint towards the virtual images PIC-A and PIC-B, the amount of viewpoint movement is minimized regardless of the vehicle speed.

[0080] Figures 2A and 2B show the state of multiple images displayed as specific examples of virtual images PIC-A and PIC-B.

[0081] As shown in Figure 2A, the virtual image PIC-A includes an image of an arrow bending to the left, an image indicating the distance ahead (40m) to the left turn point, an image indicating the gear (D), an image of a mark surrounded by a ring indicating a speed limit (60km / h), and an image indicating the actual vehicle speed (50km / h). These images are arranged from right to left.

[0082] As shown in Figure 2B, the virtual image PIC-B includes an image of an arrow bending to the left, an image indicating the distance ahead (80m) to the left turn point, an image indicating the gear (D), an image of a mark surrounded by a ring indicating the speed limit (120km / h), and an image indicating the actual vehicle speed (100km / h). These images are arranged from right to left.

[0083] The image illumination device 10 is configured to be located in front of the steering wheel 104 and near the bottom of the windshield 102.

[0084] As shown in Figure 1, the image illumination device 10 includes an image generating unit 20, a reflector 40, a housing 50, a light-transmitting cover 60, and a control unit 80. The image generating unit 20 generates a display image that serves as the source for virtual images PIC-A and PIC-B. The reflector 40 reflects the light emitted from the image generating unit 20 towards the image display unit 106 of the front window 102. The housing 50 houses the image generating unit 20 and the reflector 40. The light-transmitting cover 60 is mounted within the housing 50. The control unit 80 controls the image generating unit 20.

[0085] Figure 3 is a detailed view of part III of Figure 1. Figure 4 is a sectional view along line IV-IV of Figure 3.

[0086] As shown in FIG3, the housing 50 has a first housing 52 and a second housing 54. The second housing 54 is assembled relative to the first housing 52, which is formed with an upward opening. Specifically, the second housing 54 has an outer peripheral flange 54b, which is assembled to the first housing 52 in a state where the outer peripheral flange 54b abuts against the upper opening of the peripheral wall portion 52a of the first housing 52.

[0087] Both the first housing 52 and the second housing 54 are made of opaque resin molded material. The second housing 54 has an upper opening 54a that allows reflected light from the reflector 40 to pass through toward the image display unit 106.

[0088] The light-transmitting cover 60 is made of a colorless and transparent resin panel. The light-transmitting cover 60 is configured to cover the upper opening 54a of the second housing 54 when it is bent downwards and slightly tilted upwards towards the rear of the device. The light-transmitting cover 60 ensures the dustproofness of the internal space 12 of the housing 50 while allowing light emitted from the image generation unit 20, reflected by the reflector 40, to enter the image display unit 106.

[0089] The second housing 54 has a light-shielding portion 54c that extends obliquely downward and forward from the rear end edge of the upper opening 54a toward the interior space 12. The light-shielding portion 54c suppresses sunlight entering the interior space 12 via the front window 102 and the light-transmitting cover 60 from reaching the image generation unit 20 as direct light.

[0090] The image generation unit 20 is disposed in the rear region of the interior space 12. The reflector 40 is disposed in the front region of the interior space 12.

[0091] As shown in Figures 3 and 4, the reflector 40 is configured as a concave mirror. The reflecting surface 40a of the reflector 40 has a horizontally elongated rectangular shape when viewed from the front of the device. The image generation unit 20 is positioned at the center of the reflector 40 in the left-right direction. The specific structure of the reflector 40 will be described later.

[0092] The image generation unit 20 includes a liquid crystal panel 22, multiple light-emitting elements 24A and 24B, a substrate 26, a lens assembly 28, a lens holder 30, and a heat sink 32. The multiple light-emitting elements 24A and 24B illuminate the liquid crystal panel 22 from the back side (i.e., the rear side of the device). The substrate 26 mounts the multiple light-emitting elements 24A and 24B. The lens assembly 28 deflects and controls the emitted light from the multiple light-emitting elements 24A and 24B. The lens holder 30 supports the lens assembly 28. The heat sink 32 supports the lens holder 30.

[0093] The liquid crystal panel 22 has a horizontally elongated rectangular shape. When the liquid crystal panel 22 is arranged along a vertical plane orthogonal to the front-back direction of the device, its outer periphery is supported by a lens holder 30.

[0094] Multiple light-emitting elements 24A and 24B are white light-emitting diodes, arranged in a grid pattern. Specifically, the multiple light-emitting elements 24A and 24B are arranged at equal intervals in four locations in the vertical direction and at equal intervals in six locations in the horizontal direction, for a total of 24 locations.

[0095] When the vehicle speed is in the low to medium speed range, multiple light-emitting elements 24A in the upper part are lit, and when the vehicle speed is in the high speed range, multiple light-emitting elements 24B in the lower part are lit.

[0096] The substrate 26 is arranged in a vertical plane orthogonal to the front-back direction of the device with the light-emitting surfaces of the plurality of light-emitting elements 24A, 24B facing the front direction of the device, and the rear surface of the substrate 26 is supported by the heat sink 32.

[0097] In the lens component 28, a plurality of convex lens portions 28A and 28B are formed on the front surface of a horizontally rectangular plate-shaped portion, which is arranged along a vertical plane orthogonal to the front-rear direction of the device. The plurality of convex lens portions 28A and 28B are formed at 24 locations near the front of the plurality of light-emitting elements 24A and 24B. Thus, the plurality of convex lens portions 28A and 28B are configured to deflect the light emitted from each of the plurality of light-emitting elements 24A and 24B in a direction closer to the front of the device. The lens component 28 is supported by a lens holder 30 at the outer periphery of the plate-shaped portion. The lens holder 30 is supported by a heat sink 32 at its rear end face.

[0098] The heat sink 32 is constructed from metal components such as aluminum. The heat sink 32 has a main body 32A and multiple heat dissipation fins 32B. The main body 32A extends in a flat plate shape along a vertical plane orthogonal to the front-rear direction of the device. The multiple heat dissipation fins 32B extend from the main body 32A at intervals in the left-right direction toward the rear of the device.

[0099] The image generation unit 20 directs the emitted light from the plurality of light-emitting elements 24A and 24B into the liquid crystal panel 22 by deflecting the emitted light through the lens component 28. Thus, the image generation unit 20 is configured to generate an image for display on the liquid crystal panel 22 (i.e., an image that becomes the source of the virtual images PIC-A and PIC-B).

[0100] The reflector 40 is rotatably supported relative to the first housing 52 about an axis Ax extending in the left-right direction.

[0101] Specifically, an actuator 70 is fixed to the first housing 52, which causes the reflector 40 to rotate about axis Ax. The actuator 70 is fixed by fastening screws 72 to the lower wall of the first housing 52 through lug-shaped mounting portions 70b formed at two locations of the actuator 70.

[0102] The reflector 40 has vertical flange portions 46. The vertical flange portions 46 are formed to protrude from the left and right sides of the back surface (i.e., the surface on the front side of the device) of the reflector surface 40a of the reflector 40 towards the back surface. A pair of left and right shaft portions 48L and 48R are formed on the left and right vertical flange portions 46, protruding outward in the left and right directions along the axis Ax. The left shaft portion 48L (right side when viewed from the front of the device) is mounted on a mounting portion 52b formed on the inner surface of the peripheral wall portion 52a of the first housing 52. The right shaft portion 48R is directly connected to the output shaft 70a of the actuator 70.

[0103] The mounting portion 52b has a generally U-shaped mounting surface. An abutment portion (not shown) is formed in the second housing 54, which abuts against the shaft portion 48L mounted on the mounting portion 52b from above to position the reflector 40.

[0104] The control unit 80 shown in Figure 1 is configured to control the image generation unit 20 in accordance with the vehicle's driving conditions.

[0105] More specifically, the control unit 80 is configured to control the display content of the liquid crystal panel 22 in the image generation unit 20 or the lighting / switching of multiple light-emitting elements 24A and 24B based on vehicle speed, gear position, images from the onboard camera, the vehicle's position, and other vehicle-related information, or external information such as map data, weather, and time. Through the control unit 80, when the vehicle speed is in the low-to-medium speed range, multiple light-emitting elements 24A are illuminated to form a virtual image PIC-A; when the vehicle speed is in the high-speed range, multiple light-emitting elements 24B are illuminated to form a virtual image PIC-B.

[0106] Figure 5 is a V-direction vector view of the reflector 40 as shown in Figure 4.

[0107] As also shown in Figure 5, the reflector 40 has: an effective reflection area 42 that controls the reflection of outgoing light from the image generation unit 20; and an outer peripheral area 44 that surrounds the effective reflection area 42 throughout the entire circumference.

[0108] The reflector 40 is formed such that the outer peripheral region 44 is thicker than the effective reflection region 42. The reflector 40 is supported in the outer peripheral region 44 by the first housing 52, which serves as a reflector support component, and the drive unit.

[0109] The effective reflective area 42 has a first reflective area 42A and a second reflective area 42B. The first reflective area 42A reflects the image for display formed on the liquid crystal panel 22 as the source image of the virtual image PIC-A. The second reflective area 42B reflects the image for display formed on the liquid crystal panel 22 as the source image of the virtual image PIC-B.

[0110] Both the first reflective region 42A and the second reflective region 42B are horizontally elongated rectangular reflective regions. The first reflective region 42A is located above the second reflective region 42B. The first reflective region 42A and the second reflective region 42B partially overlap. The first reflective region 42A is narrower in width from left to right compared to the second reflective region 42B.

[0111] The outer peripheral region 44 is formed to surround the effective reflection region 42 with a substantially constant width. The left and right side portions 44a of the first reflection region 42A are wider than other general regions. A pair of vertical flange portions 46 are formed to extend obliquely downward from the left and right side portions 44a of the outer peripheral region 44 toward the front of the device.

[0112] Next, the function of this embodiment will be explained.

[0113] The image illumination apparatus 10 according to this embodiment is configured to reflect emitted light from the image generation unit 20 via a reflector 40, thereby projecting virtual images PIC-A and PIC-B onto the image display unit 106. The reflector 40 has: an effective reflection area 42 that controls the reflection of emitted light from the image generation unit 20; and an outer peripheral area 44 that surrounds the effective reflection area 42 throughout its circumference. The reflector 40 is formed such that the outer peripheral area 44 is thicker than the effective reflection area 42, and is supported in the outer peripheral area 44 by a first housing 52 serving as a reflector support member and an actuator 70. Therefore, the image illumination apparatus 10 according to this embodiment can achieve the effects described below.

[0114] The outer peripheral region 44 is formed as a thick wall compared to the effective reflection region 42, thus ensuring the required rigidity without significantly increasing the weight of the mirror 40. This allows for suppression of deformation of the mirror 40 and maintenance of its optical function.

[0115] The reflector 40 is supported by the first housing 52 and the actuator 70 in the outer peripheral region 44. Therefore, deformation that would adversely affect the function of the reflector 40 can be prevented in advance in the effective reflection region 42.

[0116] As described above, the image illumination apparatus of this embodiment is configured to project the display image generated by the image generation unit 20 as virtual images PIC-A and PIC-B onto the image display unit 106. According to this embodiment, in the image illumination apparatus described above, even if the reflector 40 that reflects the emitted light from the image generation unit 20 toward the image display unit 106 is enlarged, a lightweight and inexpensive structure can be achieved while ensuring the optical function of the reflector 40.

[0117] The image illumination apparatus of this embodiment is configured to project a virtual image PIC-A (first virtual image) into the lower region 106A of the image display unit 106, and a virtual image PIC-B (second virtual image) into the upper region 106B. The effective reflection region 42 of the reflector 40 includes: a first reflection region 42A, which reflects the display image that is the source of the virtual image PIC-A; and a second reflection region 42B, which reflects the display image that is the source of the virtual image PIC-B. The first reflection region 42A is located above the second reflection region 42B and is narrower in width from left to right compared to the second reflection region 42B. Furthermore, the reflector 40 is supported by the first housing 52 and the actuator 70 at the left and right sides 44a of the first reflection region 42A in the outer peripheral region 44. Therefore, the image illumination apparatus 10 according to this embodiment can achieve the effects described below.

[0118] As for the structure of the effective reflection area 42, when the first reflection area 42A is located above the second reflection area 42B and is narrower in width compared to the second reflection area 42B, the left and right sides of the first reflection area 42A in the outer peripheral area 44 easily provide space for the configuration of supporting the reflector 40. Therefore, by effectively utilizing this space, the rigidity of the reflector 40 supported by the first housing 52 and the actuator 70 can be adequately ensured.

[0119] The reflector 40 in this embodiment is configured as a concave mirror with a horizontally elongated rectangular shape. Since it is not easy to maintain the surface accuracy of the effective reflection area 42, the structure of this embodiment is more efficient.

[0120] Furthermore, the reflector 40 in this embodiment is configured to be supported rotatably relative to the first housing 52 and the actuator 70 about an axis Ax extending in the left-right direction. Since it is difficult to maintain the surface accuracy of the effective reflection area 42, the structure of this embodiment is more efficient.

[0121] In the above embodiment, the image generation unit 20 is described as having 12 light-emitting elements 24A and 12 light-emitting elements 24B, but it is also possible to adopt a structure with other numbers of light-emitting elements 24A and 24B.

[0122] In the above embodiment, the image display unit 106 is described as being provided on the inner surface of the front window 102, but the image display unit can also be constructed by a light-transmitting plate or the like disposed on the interior side of the front window 102.

[0123] In the above embodiment, the image illumination device 10 is described as a head-up display for vehicle use, but it can also be used for other purposes.

[0124] Next, a variation of the first embodiment will be described.

[0125] First, a first variation of the first embodiment will be described.

[0126] Figures 6A and 6B are vector views in direction II of Figure 1 showing the structure of the image illumination device involved in this modified example.

[0127] The basic structure of the image illumination device involved in this variation is the same as that in the above-described embodiment, but some of the control contents of the image illumination device are different from those in the above-described embodiment.

[0128] As shown in Figure 6A, when the vehicle speed is in the low-to-medium speed range, similar to the case in the above embodiment, a virtual image PIC-A is projected in the lower region 106A of the image display unit 106 as the first virtual image. In this modified example, it is further configured such that a virtual image PIC-C, different from the virtual image PIC-B in the above embodiment, is projected in the upper region 106B as the second virtual image, as needed.

[0129] Specifically, as shown in Figure 6B, in the event of an emergency such as when a pedestrian or other person intrudes into the path of a vehicle, a virtual image PIC-C indicating the presence of a pedestrian or other person and their directionality is additionally displayed in the upper region 106B.

[0130] By adopting the structure of this modified example, the safety of the vehicle during operation can be further improved.

[0131] Furthermore, in this modified example, it is also possible to configure the system such that when the vehicle speed is in the high-speed region without an emergency, a virtual image identical to the virtual image PIC-B in the above embodiment is projected as a second virtual image onto the upper region 106B.

[0132] Next, a second variation of the first embodiment will be described.

[0133] Figure 7 is a V-direction vector view of the reflector 240 of the image illumination device involved in this modified example, as shown in Figure 4.

[0134] The reflector 240 in this modified example, like the reflector 40 in the above embodiment, has: an effective reflection area 242; and an outer peripheral region 244 that surrounds the effective reflection area 242 throughout its circumference. The outer peripheral region 244 is formed with a thicker wall compared to the effective reflection area 242. Furthermore, in this modified example, a portion of the structure of the effective reflection area 242 and the outer peripheral region 244 differs from that in the above embodiment.

[0135] In this modified example, a pair of vertical flanges 246 are formed on the left and right sides 244a of the first reflecting region 242A in the outer peripheral region 244 of the reflector 240. Furthermore, in this modified example, the effective reflecting region 242 is formed with a constant wall thickness. In addition, unlike the embodiment described above, this modified example features an annular rib 244b that covers the entire circumference of the effective reflecting region 242 and is formed at the outermost peripheral edge of the outer peripheral region 244.

[0136] When using the structure of this modified example, it is possible to achieve roughly the same effect as the above-described embodiments.

[0137] As shown in this modified example, an annular rib 244b is additionally formed in the outer peripheral region 244 of the reflector 240. This makes it easier to maintain the optical functions required for the reflector 240 in the effective reflection region 242, and ensures the rigidity required for the reflector 240 in the outer peripheral region 244.

[0138] Next, a third variation of the first embodiment will be described.

[0139] Figure 8 is a side sectional view of the image illumination device 310 involved in this modified example.

[0140] The basic structure of this modified example is the same as that of the above-described embodiment. However, the difference between this modified example and the above-described embodiment is that the light emitted from the image generation unit 320 is sequentially reflected toward the image display unit 106 by the first reflector 340P and the second reflector 340S.

[0141] Consequently, the structure and configuration of the image generation unit 320 differ from those in the above-described embodiment, and a portion of the structure of the housing 350 also differs from those in the above-described embodiment.

[0142] In this modified example, the first reflector 340P is disposed in the rear region of the internal space 12, and the second reflector 340S is disposed in the front region of the internal space 12. The image generation unit 320 is supported by the first housing 352, disposed between the first reflector 340P and the second reflector 340S, at a position lower than the first reflector 340P and the second reflector 340S.

[0143] The image generation unit 320, like the image generation unit 20 of the above embodiment, includes a liquid crystal panel 322, a plurality of light-emitting elements 324A, 324B, a lens component 328, a lens holder 330, and a heat sink 332. The image generation unit 320 is configured to face the first reflecting mirror 340P. In the image generation unit 320, the number of light-emitting elements 324A, 324B and the convex lens portions 328A, 328B of the lens component 328 is set to be less than the corresponding number in the image generation unit 20 of the above embodiment.

[0144] The second reflector 340S is substantially the same as the reflector 40 in the above embodiment, having an effective reflection area 342 and an outer peripheral area 344.

[0145] The first reflector 340P is configured to be located obliquely above and behind the image generation unit 320, causing the emitted light from the image generation unit 320 to be reflected forward. The reflecting surface 340Pa of the first reflector 340P has a horizontally elongated rectangular shape when viewed from the front of the device. The horizontal cross-sectional shape of the reflecting surface 340Pa is composed of convex curves, and the vertical cross-sectional shape of the reflecting surface 340Pa is composed of concave curves.

[0146] The first reflector 340P is configured to reflect the emitted light from the image generation unit 320 toward the first reflection region 342A of the effective reflection region 342 when the plurality of light-emitting elements 324A are illuminated. Furthermore, the first reflector 340P is configured to reflect the emitted light from the image generation unit 320 toward the second reflection region 342B of the effective reflection region 342 when the plurality of light-emitting elements 324B are illuminated.

[0147] By adopting the structure of this modified example, it is possible to achieve roughly the same effect as the above-described implementation.

[0148] As shown in this modified example, in the structure in which the emitted light from the image generation unit 320 is reflected sequentially by the first reflector 340P and the second reflector 340S, the first reflector 340P can also be configured to converge the emitted light from the image generation unit 320 in the vertical direction on the side further back of the device than the second reflector 340S.

[0149] The second embodiment of the present invention will now be described with reference to the accompanying drawings.

[0150] (Second Implementation)

[0151] Figure 9 is a side sectional view showing the image illumination device 10X according to the second embodiment mounted on a vehicle 100. Figure 10 is a vector view in the X direction of Figure 9. In the structure shown in Figure 9, structures identical to those shown in Figure 1 are labeled with the same reference numerals, and their descriptions are omitted.

[0152] As shown in Figures 9 and 10, the image illumination device 10X according to this embodiment is configured to project a virtual image PIC onto the image display unit 102A set on the inner surface of the front window 102 when it is disposed in the interior of the vehicle 100.

[0153] The optical path RX shown in Figure 9 is the optical path when the driver 2 visually perceives the virtual image PIC projected onto the image display unit 102A by the image illumination device 10X.

[0154] The image display unit 102A is positioned in the lower region of the windshield 102 and in front of the steering wheel 104, and has a horizontally elongated rectangular shape. This allows the driver 2 of the vehicle 100 to easily visually perceive the virtual image PIC projected on the image display unit 102A.

[0155] Figure 10 shows a specific example of a virtual image PIC, displaying a left-pointing arrow and a vehicle speed (50 km / h).

[0156] As shown in Figure 9, the image illumination device 10X includes an image generating unit 20X, a first reflector 70X and a second reflector 80X, a housing 50, and a light-transmitting cover 60. The image generating unit 20X generates a display image that serves as the source for a virtual image PIC. The first reflector 70X and the second reflector 80X sequentially reflect the light emitted from the image generating unit 20X toward the image display unit 102A of the front window 102. The housing 50 houses the image generating unit 20X, the first reflector 70X, and the second reflector 80X. The light-transmitting cover 60 is mounted on the housing 50.

[0157] An upper opening 54aX is formed in the second housing 54X, which allows reflected light from the second reflector 80X to pass through toward the image display unit 102A.

[0158] The light-transmitting cover 60 ensures the dustproofness of the internal space 12 of the housing 50 while allowing reflected light from the second reflector 80X to enter the image display unit 102A.

[0159] The image generating unit 20X and the first reflector 70X are disposed in the rear region of the internal space 12, and the second reflector 80X is disposed in the front region of the internal space 12. The reflecting surface 70aX of the first reflector 70X has a bilaterally symmetrical shape. The reflecting surface 80aX of the second reflector 80X also has a bilaterally symmetrical shape. The image generating unit 20X is disposed at the center position in the left-right direction of the first reflector 70X and the second reflector 80X. The image generating unit 20X is supported by the lower wall portion 52bX of the first housing 52X (described later).

[0160] The first reflector 70X is configured to be positioned approximately directly above the image generation unit 20X, causing the emitted light from the image generation unit 20X to be reflected forward. The reflecting surface 70aX of the first reflector 70X has a horizontally elongated rectangular shape when viewed from the front of the device. The horizontal cross-sectional shape of the reflecting surface 70aX is composed of a convex curve, and the vertical cross-sectional shape of the reflecting surface 70aX is composed of a concave curve.

[0161] The second reflector 80X is positioned in front of the first reflector 70X. The second reflector 80X is configured to reflect the outgoing light from the image generation unit 20X reflected by the first reflector 70X upwards.

[0162] The second reflecting mirror 80X is a concave mirror. The surface shape of the reflecting surface 80aX of the second reflecting mirror 80X is composed of a concave curved surface that is approximately spherical. When viewed from the front of the device, the reflecting surface 80aX of the second reflecting mirror 80X has a horizontally elongated rectangular shape and is formed in a larger size than the reflecting surface 70aX of the first reflecting mirror 70X.

[0163] The second reflector 80X is rotatably supported relative to the first housing 52X about an axis Ax extending in the left-right direction. Specifically, the second reflector 80X has a pair of flanges 80b on the left and right sides, which are formed to protrude from the left and right ends of the second reflector 80X toward the back side of the reflecting surface 80aX. One flange 80b is connected to an actuator 82 fixed to the first housing 52X. The second reflector 80X rotates about the axis Ax by being driven by the actuator 82, thereby allowing adjustment of the vertical position of the reflected light from the second reflector 80X on the virtual image PIC formed in the image display unit 102A.

[0164] Next, the image generation unit 20X and its surrounding structure will be described.

[0165] Figure 11 is a detailed view of part XI of Figure 9, and Figure 12 is a detailed view of part XII of Figure 11.

[0166] As shown in Figures 11 and 12, the image generation unit 20X includes a liquid crystal panel 22, an optical unit 30X, a panel support member 24, and a mask member 26X. The optical unit 30X illuminates the liquid crystal panel 22 from the back side (i.e., the bottom side). The panel support member 24 supports the liquid crystal panel 22. The mask member 26X covers the outer peripheral area of ​​the liquid crystal panel 22.

[0167] Between the optical unit 30X and the liquid crystal panel 22, a diffuser plate 28X is arranged to extend along the lower surface of the liquid crystal panel 22, which diffuses the light emitted from the optical unit 30X into the liquid crystal panel 22 as diffused light.

[0168] The liquid crystal panel 22 is arranged along a horizontal plane. The liquid crystal panel 22 is supported by the panel support member 24 via the diffuser plate 28X at its outer periphery.

[0169] The optical unit 30X includes: a plurality of light-emitting elements 32X; a substrate 34 on which the plurality of light-emitting elements 32X are mounted; and a lens component 36 which deflects and controls the emitted light from the plurality of light-emitting elements 32X.

[0170] The multiple light-emitting elements 32X are all white light-emitting diodes, arranged in a grid pattern. Specifically, these multiple light-emitting elements 32X are arranged at two locations with a constant interval in the front-to-back direction, and at five locations with equal intervals in the left-to-right direction, for a total of 10 locations.

[0171] The substrate 34 is arranged along a horizontal plane with the light-emitting surfaces of the plurality of light-emitting elements 32X facing upwards. The substrate 34 is supported by a heat sink 40X on its lower surface.

[0172] The heat sink 40X is made of metal components such as aluminum. The heat sink 40X has: a main body 40A that extends in a flat plate shape along a horizontal plane; and a plurality of heat dissipation fins 40B that extend downward from the main body 40A at intervals in the left-right direction.

[0173] In the lens component 36, a plurality of convex lens portions 36a are formed on the upper surface of a horizontally elongated rectangular plate-shaped portion arranged along a horizontal plane. The plurality of convex lens portions 36a are formed at 10 locations directly above the plurality of light-emitting elements 32X. Thus, the plurality of convex lens portions 36a are configured to deflect the emitted light from each of the plurality of light-emitting elements 32X in a direction directly upward. The lens component 36 is supported by a panel support member 24 at the outer periphery of the plate-shaped portion.

[0174] The image generation unit 20X controls the deflection of the emitted light from the multiple light-emitting elements 32X via the lens component 36, and then directs the emitted light into the liquid crystal panel 22 via the diffuser plate 28X. Thus, the image generation unit 20X is configured to generate a display image (i.e., an image that becomes the source of a virtual image PIC) on the liquid crystal panel 22 with uniform brightness.

[0175] A recess 52b1 is formed in the lower wall portion 52bX of the first housing 52X. The recess 52b1 has an inner circumferential surface shape that is substantially the same as the outer shape of the main body portion 40A of the heat sink 40X. A rectangular opening 52b2 is formed in the recess 52b1 for inserting and passing through a plurality of heat dissipation fins 40B.

[0176] The radiator 40X is received in the recess 52b1 with a plurality of heat dissipation fins 40B inserted through the opening 52b2 relative to the lower wall portion 52bX of the first housing 52X. In this state, the main body portion 40A of the radiator 40X is placed in the recess 52b1 around the opening 52b2.

[0177] The panel support component 24 is made of opaque resin molding. The panel support component 24 is positioned and fixed to the first housing 52X by co-fastening with the heat sink 40X.

[0178] That is, a pair of front and rear lugs 24a extending laterally are formed on the left and right sides of the panel support member 24. When the panel support member 24 is placed on the main body 40A of the heat sink 40X, the two pairs of lugs 24a are fastened to the lower wall 52bX of the first housing 52X by screws 42X via the main body 40A.

[0179] Figure 13 is a perspective view showing the image generation unit 20X together with the heat sink 40X. Figure 14 is an exploded perspective view showing the image generation unit 20X.

[0180] The mask component 26X is constructed from components with a higher thermal conductivity than the liquid crystal panel 22 (specifically, metal components such as aluminum). As shown in Figures 13 and 14, the mask component 26X has a mask body 26A, a front and rear pair of flanges 26B, and a left and right pair of flanges 26C. The mask body 26A extends in a flat plate shape along a horizontal plane. The front and rear pair of flanges 26B extends downward from the front and rear end edges of the mask body 26A. The left and right pair of flanges 26C extends downward from the left and right end edges of the mask body 26A.

[0181] A pair of front and rear flanges 26B are formed across the entire width of the mask body 26A. A pair of left and right flanges 26C are formed at the middle position of the front and rear lugs 24a.

[0182] An opening 26Aa, which is a horizontally elongated rectangular shape and is slightly smaller than the liquid crystal panel 22, is formed in the mask body 26A. That is, the mask component 26X is configured to cover the outer peripheral area of ​​the liquid crystal panel 22.

[0183] The mask component 26X is fixed to the panel support component 24 by riveting (specifically by thermal riveting). The thermal riveting is performed at three locations: the center position in the left-right direction on the front side of the opening 26Aa, and the left and right ends on the rear side of the opening 26Aa.

[0184] As shown in Figure 14, rivet pins 24b are formed at the aforementioned three locations on the upper surface of the panel support member 24. Pin insertion holes 26Ab are formed at the aforementioned three locations in the mask body 26A, through which the rivet pins 24b are inserted. The pin insertion hole located in front of the opening 26Aa is a round hole, while the other two pin insertion holes are elongated holes extending in the left-right direction.

[0185] A pair of locating pins 24c are formed on the upper surface of the panel support member 24, positioned forward of the pair of rivet pins 24b. A pair of pin insertion holes 26Ac are formed in the mask body 26A, through which the pair of locating pins 24c are inserted. Both the left and right pin insertion holes 26Ac are elongated holes extending in the front-rear direction.

[0186] The rivet pins 24b of the three locations are inserted through the pin insertion holes 26Ab of the three locations, and the left and right pair of positioning pins 24c are inserted through the left and right pair of pin insertion holes 26Ac. In this state, the front ends of the rivet pins 24b of the three locations are heated and flattened, thereby performing thermal riveting of the mask component 26X relative to the panel support component 24 as shown in FIG13.

[0187] By performing the thermal riveting as described above, the mask component 26X is positioned in the horizontal plane relative to the panel support component 24. In this state, the lower end faces of the front and rear pairs of flanges 26B and the left and right pairs of flanges 26C abut against the upper surface of the main body 40A of the heat sink 40X.

[0188] Next, the function of this embodiment will be explained.

[0189] The image illumination apparatus 10X according to this embodiment includes an image generation unit 20X, which generates a virtual image PIC projected onto an image display unit 102A. Specifically, the image illumination apparatus 10X includes, as the image generation unit 20X: a liquid crystal panel 22; an optical unit 30X that provides backlight illumination to the liquid crystal panel 22; a panel support member 24 that supports the liquid crystal panel 22; and a mask member 26X that covers the outer peripheral area of ​​the liquid crystal panel 22. Therefore, the image illumination apparatus 10X according to this embodiment can achieve the following effects.

[0190] The image illumination device 10X, by configuring the mask component 26X, can define the usable area of ​​the liquid crystal panel 22. In addition, even in the event of sunlight S entering the internal space 12 of the image illumination device 10X as shown in FIG. 9, the image illumination device 10X can suppress the temperature rise of the liquid crystal panel 22 to a certain extent by means of the light-shielding function of the mask component 26X.

[0191] Furthermore, in the image illumination apparatus 10X according to this embodiment, the heat sink 40X that mounts the optical unit 30X is fixed to the panel support member 24. Also, the mask member 26X is composed of a component with a thermal conductivity higher than that of the liquid crystal panel 22, and is fixed to the panel support member 24 in a state of contact with the heat sink 40X. Therefore, the image illumination apparatus 10X according to this embodiment can achieve the effects described below.

[0192] Even if the liquid crystal panel 22 heats up due to backlighting or sunlight from the optical unit 30X, heat can be dissipated to the heat sink 40X via the mask component 26X, which has a higher thermal conductivity than the liquid crystal panel 22. This effectively suppresses overheating of the liquid crystal panel 22. Furthermore, high output of the optical unit 30X can be achieved while maintaining the functionality of the liquid crystal panel 22.

[0193] Furthermore, the image illumination apparatus 10X according to this embodiment does not use a dedicated heat-conducting panel, but achieves the aforementioned effects by using a mask component 26X that defines the usage area of ​​the liquid crystal panel 22. Therefore, according to this embodiment, a bright virtual image PIC can be generated while suppressing the cost of the image illumination apparatus 10X.

[0194] As described above, according to this embodiment, when the image for display generated by the image generation unit 20X is projected as a virtual image PIC into the image display unit 102A, a bright virtual image PIC can be generated while suppressing the cost of the image illumination unit 10X.

[0195] In this embodiment, since the mask component 26X is fixed relative to the panel support component 24 by riveting, the following effects can be achieved.

[0196] According to this embodiment, the number of components of the image illumination device 10X can be reduced compared to fixing by means of screws or the like.

[0197] In addition, compared with fixing by means of interlocking, it is less likely to apply excessive load to the liquid crystal panel 22, and it can avoid the accidental generation of gaps between the panel support member 24 and the mask member 26X that could cause the mask member 26X to vibrate.

[0198] Furthermore, in this embodiment, the panel support member 24 is made of resin, and the mask member 26X is fixed to the panel support member 24 by hot riveting. Therefore, fixing can be performed more easily than cold riveting.

[0199] The image illumination apparatus 10X according to this embodiment includes a first reflector 70X and a second reflector 80X that sequentially reflect light emitted from the image generation unit 20X toward the image display unit 102A. Since the second reflector 80X is configured as a concave mirror, as shown in FIG9, sunlight S incident on the internal space 12 of the image illumination apparatus 10X is easily focused toward the end of the liquid crystal panel 22 by being sequentially reflected by the second reflector 80X and the first reflector 70X. Therefore, as in this embodiment, the light-shielding function of the mask member 26X, which is arranged to cover the outer peripheral area of ​​the liquid crystal panel 22, effectively suppresses the temperature rise of the liquid crystal panel 22.

[0200] In the above embodiment, the optical unit 30X is provided with a lens component 36, which has a structure of 10 light-emitting elements 32X and 10 convex lens portions 36a. However, it is also possible to adopt a structure with other numbers of light-emitting elements 32X and convex lens portions 36a.

[0201] In the above embodiment, the mask component 26X was described as being fixed to the panel support component 24 by hot riveting, but a structure that can be fixed by cold riveting is also possible. By adopting the structure described above, it becomes easy to use a metal component or the like as the panel support component 24.

[0202] In the above embodiment, it was described with a first reflector 70X and a second reflector 80X, but it can also be configured to have only a second reflector 80X. In addition, it can also be configured to directly inject the emitted light from the image generation unit 20X into the image display unit 102A.

[0203] In the above embodiment, the image display unit 102A is described as being provided on the inner surface of the front window 102, but the image display unit can also be provided by a light-transmitting plate or the like disposed on the interior side of the front window 102.

[0204] Next, a variation of the second embodiment will be described.

[0205] Figure 15 is a perspective view showing the image generation unit 120 of the image illumination apparatus involved in this modified example together with the heat sink 40X.

[0206] The basic structure of the image generation unit 120 in this modified example is the same as that in the above embodiment, but the structure of the mask component 126 is different from that in the above embodiment.

[0207] The mask component 126 in this modified example is also similar to the mask component 26X in the above embodiment, consisting of a metal component having a mask body portion 126A, a front and rear pair of flange portions 126B, and a left and right pair of flange portions 126C. The difference between this modified example and the above embodiment is that openings 126Aa1 and 126Aa2 are further formed at two locations in the mask body portion 126A.

[0208] Specifically, opening 126Aa1 is formed at the front of mask body 126A, and opening 126Aa2 is formed at the rear of mask body 126A. Both openings 126Aa1 and 126Aa2 are formed with a left-right width narrower than that of the liquid crystal panel 22. Opening 126Aa1 is formed with a left-right width narrower than opening 126Aa2, and also with a front-back width narrower than opening 126Aa2.

[0209] Thus, in the mask component 126, a beam-shaped portion 126Ad extending in the left-right direction is formed between the two openings 126Aa1 and 126Aa2 in the mask body portion 126A.

[0210] When using the structure of this modified example, the same effect as in the above-described embodiment can also be obtained.

[0211] Furthermore, by forming openings 126Aa1 and 126Aa2 at two locations on the mask component 126, this modified example achieves the effects described below.

[0212] In the mask component 126, a beam-shaped portion 126Ad is formed between the openings 126Aa1 and 126Aa2 at two locations. This improves the rigidity of the mask component 126 and allows the heat generated by the liquid crystal panel 22 to be conducted to the heat sink 40X more efficiently.

[0213] Furthermore, in this modified example, two application areas are set at two locations on the liquid crystal panel 22. This allows two virtual images (PICs) to be projected onto the two locations of the image display unit 102A.

[0214] Specifically, in this modification, the usable area of ​​the liquid crystal panel 22 is defined by the opening 126Aa1 formed at the front position, thereby enabling the formation of a virtual image PIC in the lower region of the image display unit 102A. Furthermore, in this modification, the usable area of ​​the liquid crystal panel 22 is defined by the opening 126Aa2 formed at the rear position, thereby enabling the formation of a virtual image PIC in the upper region of the image display unit 102A.

[0215] When using the structure of this modified example, the same effect as in the above-described embodiment can also be obtained.

[0216] Furthermore, the numerical values ​​shown as elements in the above embodiments and their variations are merely examples, and these elements can certainly be appropriately set to different values.

[0217] Furthermore, the present invention is not limited to the structures described in the above embodiments and their variations, and various other modifications can be incorporated into the structures.

[0218] The structures described in the following items also constitute a part of this invention.

[0219] Project 1: An image illumination device configured to project a display image generated by an image generation unit as a virtual image onto an image display unit. The image illumination device includes: a reflector that reflects light emitted from the image generation unit toward the image display unit; and a reflector support member that supports the reflector. The reflector has: an effective reflection area that controls the reflection of light emitted from the image generation unit; and an outer peripheral area that surrounds the effective reflection area throughout its circumference. The outer peripheral area is formed as a thick wall compared to the effective reflection area, and the reflector is supported by the reflector support member in the outer peripheral area.

[0220] Project 2: According to the image illumination device described in Project 1, the image illumination device is configured to project a first virtual image as the virtual image in the lower region of the image display section and a second virtual image in the upper region. The effective reflection region has a first reflection region that reflects the display image that is the source of the first virtual image and a second reflection region that reflects the display image that is the source of the second virtual image. The first reflection region is a region that is narrower in width on the left and right sides than the second reflection region on the upper side of the second reflection region. The mirror is supported by the mirror support member on the left and right sides of the first reflection region in the outer peripheral region.

[0221] Item 3: The image illumination apparatus according to Item 1 or 2, wherein the effective reflective area is formed by a constant wall thickness, and the outer peripheral area has annular ribs formed to surround the effective reflective area throughout the circumference.

[0222] Item 4: An image illumination device according to any one of Items 1 to 3, wherein the reflector is configured as a concave mirror having a horizontally elongated rectangular shape.

[0223] Item 5: An image illumination apparatus according to any one of Items 1 to 4, wherein the reflector is rotatably supported relative to the reflector support member about an axis extending in the left-right direction.

[0224] Project 6: An image illumination apparatus configured to project a display image generated by an image generation unit as a virtual image onto an image display unit. In this image illumination apparatus, the image generation unit includes: a liquid crystal panel; an optical unit that backlights the liquid crystal panel; a panel support member that supports the liquid crystal panel; and a mask member that covers the outer peripheral area of ​​the liquid crystal panel. The optical unit is mounted on a heat sink fixed to the panel support member. The mask member is composed of a component with a thermal conductivity higher than that of the liquid crystal panel and is fixed to the panel support member in a manner that contacts the heat sink.

[0225] Item 7: The image illumination apparatus according to Item 6, wherein the mask component is fixed relative to the panel support component by riveting.

[0226] Item 8: The image illumination device according to Item 7, wherein the panel support component is made of resin and the riveting is performed by thermal riveting.

[0227] Item 9: An image illumination apparatus according to any one of Items 6 to 8, wherein openings are formed at two locations of the mask component.

[0228] Item 10: An image illumination apparatus according to any one of Items 6 to 9, wherein a concave mirror is provided, which causes emitted light from the image generation unit to reflect toward the image display unit.

[0229] This application claims priority based on Japanese Application No. 2023-185241, filed on October 30, 2023, and Japanese Application No. 2023-171169, filed on October 2, 2023, and incorporates all the contents set forth in the aforementioned Japanese applications.

Claims

1. An image illumination apparatus configured to project a display image generated by an image generation unit as a virtual image onto an image display unit, wherein the image illumination apparatus includes: a reflector that reflects light emitted from the image generation unit toward the image display unit; And a mirror support component that supports the mirror, the mirror having: an effective reflection area that controls the reflection of outgoing light from the image generation unit; The mirror also includes an outer peripheral region that extends around the entire perimeter and surrounds the effective reflection area. The outer peripheral region is formed as a thick wall compared to the effective reflection area, and the mirror is supported by the mirror support member in the outer peripheral region.

2. The image illumination device according to claim 1, wherein, The image illumination device is configured to project a first virtual image as the virtual image in the lower region of the image display unit and a second virtual image in the upper region. The effective reflection region has a first reflection region that reflects the display image that is the source of the first virtual image and a second reflection region that reflects the display image that is the source of the second virtual image. The first reflection region is a region that is narrower in width from left to right than the second reflection region on the upper side. The mirror is supported by the mirror support member on the left and right sides of the first reflection region in the outer peripheral region.

3. The image illumination apparatus according to claim 1 or 2, wherein, The effective reflective area is formed with a constant wall thickness, and the outer peripheral area has annular ribs formed to cover the entire circumference and surround the effective reflective area.

4. The image illumination apparatus according to claim 1 or 2, wherein, The reflector is configured as a concave mirror with a horizontally elongated rectangular shape.

5. The image illumination apparatus according to claim 1 or 2, wherein, The reflector is supported in a way that allows it to rotate relative to the reflector support member about an axis extending in the left-right direction.

6. An image illumination apparatus configured to project a display image generated by an image generation unit as a virtual image onto an image display unit, wherein the image generation unit comprises: a liquid crystal panel; an optical unit for backlighting the liquid crystal panel; a panel support member for supporting the liquid crystal panel; and a mask member for covering the outer peripheral area of ​​the liquid crystal panel, wherein the optical unit is mounted on a heat sink fixed to the panel support member, and the mask member is composed of a component with a thermal conductivity higher than that of the liquid crystal panel and is fixed to the panel support member in a manner that contacts the heat sink.

7. The image illumination apparatus according to claim 6, wherein, The mask component is fixed relative to the panel support component by riveting.

8. The image illumination apparatus according to claim 7, wherein, The panel support component is made of resin, and the riveting is performed by hot riveting.

9. The image illumination apparatus according to claim 6 or 7, wherein, Openings are formed at two locations on the mask component.

10. The image illumination apparatus according to claim 6 or 7, wherein, It has a concave mirror that reflects the emitted light from the image generation unit toward the image display unit.

Images