Image irradiation device

Abstract

To provide an image irradiation device configured to project a display image generated by an image generation unit as a virtual image on an image display section, the image irradiation device having a light-weight and inexpensive configuration while securing an optical function even if a reflector for reflecting light emitted from the image generation unit toward the image display section is increased in size.SOLUTION: A reflector 40 includes: an effective reflection region 42 for performing reflection control of light emitted from an image generation unit 20; and an outer peripheral edge region 44 for surrounding the entire circumference of the region, and the outer peripheral edge region 44 is formed thicker than the effective reflection region 42. Thus, necessary rigidity can be secured without increasing weight of the reflector 40 so much. Thus, deformation of the reflector 40 is suppressed and the optical function can be maintained. After that, the reflector 40 is supported by a first housing 52 or the like in the outer peripheral edge region 44. As a result, the effective reflection region 42 is prevented from being deformed.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an image projection device configured to project an image for display generated by an image generating unit as a virtual image on an image display section. [Background technology]

[0002] Conventionally, there has been known an in-vehicle image projection device that is configured to project a virtual image onto an image display unit such as a front window (i.e., windshield) or a light-transmitting plate arranged on the inside of the vehicle cabin when placed inside the vehicle cabin.

[0003] As a configuration of such an image projection device, for example as described in "Patent Document 1," a device is known that includes an image generating unit that generates a display image that is the basis of the virtual image, a reflecting mirror that reflects light emitted from the image generating unit toward the image display section, and a reflecting mirror support member that supports the reflecting mirror.

[0004] The image projection device described in "Patent Document 1" is configured to include, as its reflecting mirrors, first and second reflecting mirrors that sequentially reflect the light emitted from the image generating unit toward the image display section. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2023-76351 A Summary of the Invention [Problem to be solved by the invention]

[0006] The image projection device described in the above-mentioned "Patent Document 1" has a reflector (specifically, the second reflector) that has a relatively large reflecting surface. If the external shape of this reflecting surface were to become even larger than this, the reflector would be prone to deformation, making it difficult to ensure the rigidity required to maintain its optical function.

[0007] One approach to this problem would be to increase the thickness of the reflector to increase its rigidity; however, this would increase the weight of the reflector and the time required to mold it would increase, resulting in increased costs.

[0008] On the other hand, it is possible to reinforce the reflector by attaching a frame member or the like without increasing the thickness of the reflector itself. However, in this case, the number of parts increases, resulting in increased costs and weight.

[0009] Such a problem can also occur in image projection devices other than those mounted on vehicles.

[0010] The present invention has been made in consideration of the above circumstances, and aims to provide an image projection device configured to project a display image generated by an image generation unit onto an image display unit as a virtual image, which can realize a lightweight and inexpensive configuration while ensuring the optical function even if the reflector for reflecting the outgoing light from the image generation unit towards the image display unit is enlarged. [Means for solving the problem]

[0011] The present invention is intended to achieve the above object by improving the structure of the reflecting mirror.

[0012] That is, the image projection device according to the present invention is An image projection device configured to project a display image generated by an image generation unit on an image display unit as a virtual image, a reflector that reflects the light emitted from the image generating unit toward the image display unit, and a reflector support member that supports the reflector, the reflecting mirror includes an effective reflection area that controls reflection of light emitted from the image generating unit, and an outer peripheral edge area that completely surrounds the effective reflection area, the outer peripheral region is formed to be thicker than the effective reflection region, The reflector is characterized in that the reflector is supported at the outer peripheral region by the reflector support member.

[0013] The above-mentioned "image projection device" is not particularly limited in its specific use as long as it is configured to project a virtual image on an image display unit, and can be used, for example, as an in-vehicle head-up display.

[0014] The specific configuration of the above-mentioned "image display unit" is not particularly limited as long as it is configured to project a virtual image, and for example, a translucent plate arranged on the front window of the vehicle or on the inside of the passenger compartment can be used.

[0015] In the above-mentioned "reflecting mirror," the specific boundary position between the effective reflection area and the outer peripheral area is not particularly limited.

[0016] The "reflecting mirror" is not particularly limited in terms of the specific thickness of each of its components, so long as the outer peripheral region is formed to be thicker than the effective reflective region.

[0017] As long as the "reflector" is supported by a reflector supporting member at its outer periphery, the specific supporting structure is not particularly limited. Effect of the Invention

[0018] The image projection device of the present invention is configured to project a display image generated by an image generating unit as a virtual image on an image display section, and is configured to reflect light emitted from the image generating unit toward the image display section by a reflecting mirror. This reflecting mirror has an effective reflection area that controls the reflection of the light emitted from the image generating unit, and an outer peripheral edge area that surrounds this area. In addition, the outer peripheral edge area of ​​the reflecting mirror is formed to be thicker than the effective reflection area, and the reflecting mirror is supported by a reflecting mirror support member at the outer peripheral edge area, so that the following effects can be obtained.

[0019] That is, by forming the outer peripheral region to be thicker than the effective reflection region, it is possible to ensure the necessary rigidity without significantly increasing the weight of the reflector, thereby suppressing deformation of the reflector and maintaining its optical function.

[0020] Furthermore, by configuring the reflector support member to support the reflector in the outer peripheral region, it is possible to prevent deformations in the effective reflection region that could adversely affect the function of the reflector.

[0021] Thus, according to the present invention, in an image projection device configured to project a display image generated by an image generating unit onto an image display unit as a virtual image, even if the reflector for reflecting the emitted light from the image generating unit toward the image display unit is enlarged, a lightweight and inexpensive configuration can be realized while ensuring the optical function.

[0022] In the above configuration, it is also possible to configure the image projection device so that the first virtual image is projected in the lower region of the image display unit as the virtual image and the second virtual image is projected in the upper region. In this case, the effective reflection region of the reflecting mirror is provided with a first reflection region for reflecting the display image that is the source of the first virtual image and a second reflection region for reflecting the display image that is the source of the second virtual image, the first reflection region is set above the second reflection region as a region narrower in left-right width than the second reflection region, and the reflecting mirror is supported by the reflecting mirror support member at both left and right portions of the first reflection region in the outer peripheral region, and the following operational effects can be obtained.

[0023] That is, when the first reflection area is set above the second reflection area and has a narrower width than the second reflection area, it is easy to secure space for arranging a structure for supporting the reflector on both sides of the first reflection area in the outer peripheral area. Therefore, by effectively using this space, it is possible to secure sufficient rigidity for the reflector supported by the reflector support member.

[0024] In the above configuration, if the reflector is configured so that the effective reflection area is formed with a constant thickness and an annular rib surrounding the entire effective reflection area is formed in the outer peripheral region, it becomes even easier to maintain the optical function required as a reflector in the effective reflection area while ensuring the rigidity required as a reflector in the outer peripheral region.

[0025] In the above configuration, if the reflector is configured as a concave mirror having a rectangular outer shape, it becomes difficult to maintain the surface precision of the effective reflection area, so it is even more effective to adopt the configuration of the present invention.

[0026] In the above configuration, if the reflector is supported so as to be rotatable about an axis extending in the left-right direction relative to the reflector support member, it becomes difficult to maintain the surface precision of the effective reflection area, so it is even more effective to adopt the configuration of the present invention. [Brief description of the drawings]

[0027] [Figure 1] FIG. 1 is a side cross-sectional view showing an image projection device according to an embodiment of the present invention mounted on a vehicle. [Diagram 2] View from the direction of arrow II in Figure 1 [Diagram 3] Detailed view of part III in Fig. 1 [Figure 4] Cross-sectional view of line IV-IV in Figure 3 [Diagram 5] 5 is a view taken in the direction of the arrow V in FIG. 4, showing the reflector of the image projection device in detail. [Figure 6] FIG. 3 is a view similar to FIG. 2, showing a first modified example of the embodiment; [Figure 7] FIG. 7 is a view similar to FIG. 5, showing a second modification of the embodiment; [Figure 8] FIG. 2 is a view similar to FIG. 1, showing a third modified example of the embodiment; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0029] Fig. 1 is a side cross-sectional view showing an image projection device 10 according to this embodiment in a state where it is mounted on a vehicle 100. Fig. 2 is a view seen in the direction of the arrow II in Fig. 1.

[0030] 1 and 2, the direction indicated by X is the "forward" of the image projection device 10 (also the "forward" of the vehicle), the direction indicated by Y is the "leftward" direction perpendicular to the "forward", and the direction indicated by Z is the "upward" direction. This is the same in other figures besides FIG. 1 and 2.

[0031] As shown in Figures 1 and 2, the image projection device 10 of this embodiment is an in-vehicle head-up display, and is configured to project two types of virtual images PIC-A and PIC-B onto an image display unit 106 set on the inner surface of a front windshield 102 when placed in the passenger compartment of a vehicle 100.

[0032] An optical path R shown in FIG. 1 is an optical path when the driver 2 visually recognizes the virtual images PIC-A and PIC-B projected on the image display unit 106 by the image projection device 10.

[0033] The image display unit 106 is positioned in a lower area of ​​the windshield 102 and in a forward area of ​​the steering wheel 104, and is set as a horizontally elongated rectangular area. This allows the driver 2 of the vehicle 100 to easily visually recognize the virtual images PIC-A and PIC-B projected on the image display unit 106.

[0034] 2, the image display unit 106 includes a lower region 106A and an upper region 106B. Both the lower region 106A and the upper region 106B are horizontally elongated rectangular regions, with the upper edge of the lower region 106A partially overlapping the lower edge of the upper region 106B, and the upper region 106B being set to be slightly horizontally elongated compared to the lower region 106A.

[0035] The two types of virtual images PIC-A and PIC-B are arranged so that the virtual image PIC-A is displayed in a lower region 106A of the image display section 106, and the virtual image PIC-B is displayed in an upper region 106B of the image display section 106.

[0036] Specifically, when the vehicle speed is in the low-medium speed range (for example, a speed range of 80 Km / h or less), the virtual image PIC-A is displayed in the lower area 106A as shown in Fig. 2(a), and when the vehicle speed exceeds the low-medium speed range and enters a high-speed range, the virtual image PIC-B is displayed in the upper area 106B as shown in Fig. 2(b). This allows the driver 2 to move his / her viewpoint from the field of view ahead of the vehicle to the virtual images PIC-A and PIC-B, with the amount of viewpoint movement being as small as possible regardless of the vehicle speed.

[0037] FIG. 2 shows a state in which six images are displayed as specific examples of virtual images PIC-A and PIC-B.

[0038] That is, as shown in Figure 2(a), the virtual image PIC-A is composed of an image of an arrow bent to the left and an image indicating the distance ahead (40 m) to the left turn point, an image indicating the gear shift position (D), an image indicating the speed limit (60 km / h) surrounded by a circle, and an image indicating the actual vehicle speed (50 km / h), arranged from right to left.

[0039] As shown in Figure 2(b), the virtual image PIC-B is composed of an image of an arrow bent to the left and an image indicating the distance ahead (80 m) to the left turn point, an image indicating the gear shift position (D), an image indicating the speed limit (120 km / h) surrounded by a circle, and an image indicating the actual vehicle speed (100 km / h), arranged from right to left.

[0040] The image projection device 10 is disposed so as to be located in front of the steering wheel 104 and in the vicinity of the lower part of the windshield 102 .

[0041] As shown in FIG. 1, the image projection device 10 includes an image generation unit 20 that generates display images that are the basis for virtual images PIC-A and PIC-B, a reflector 40 that reflects the light emitted from the image generation unit 20 toward an image display section 106 on the front window 102, a housing 50 that accommodates the image generation unit 20 and the reflector 40, a translucent cover 60 attached to the housing 50, and a control unit 80 that controls the image generation unit 20.

[0042] 3 is a detailed view of a portion III in FIG. 1, and FIG. 4 is a cross-sectional view taken along line IV-IV in FIG.

[0043] 3, the housing 50 has a configuration in which a first housing 52 formed to open upward is fitted with a second housing 54. Specifically, the second housing 54 has an outer peripheral flange portion 54b, and is fitted to the first housing 52 with the outer peripheral flange portion 54b in contact with an upper end surface of a peripheral wall portion 52a of the first housing 52.

[0044] The first and second housings 52 and 54 are both made of opaque resin moldings. The second housing 54 has an upper opening 54a formed therein for transmitting the light reflected from the reflecting mirror 40 toward the image display unit 106.

[0045] The light-transmitting cover 60 is made of a colorless and transparent resin panel. The light-transmitting cover 60 is arranged to cover the upper opening 54a of the second housing 54 in a state where it is curved downward and inclined slightly upward toward the rear of the device. The light-transmitting cover 60 allows the emitted light from the image generating unit 20 reflected by the reflecting mirror 40 to enter the image display section 106, while ensuring the dustproofness of the internal space 12 of the housing 50.

[0046] The second housing 54 is formed with a light-shielding piece 54c that extends obliquely downward and forward from the rear end edge of the upper opening 54a toward the internal space 12. The light-shielding piece 54c prevents sunlight that has entered the internal space 12 through the front window 102 and the light-transmitting cover 60 from reaching the image generating unit 20 as direct light.

[0047] The image generating unit 20 is arranged in a rear region of the interior space 12 and the reflector 40 is arranged in a front region of the interior space 12 .

[0048] 3 and 4, the reflecting mirror 40 is configured as a concave mirror, and the reflecting surface 40a has a horizontally elongated rectangular shape when viewed from the front of the device. The image generating unit 20 is disposed so as to be located at the center in the left-right direction of the reflecting mirror 40. The specific configuration of the reflecting mirror 40 will be described later.

[0049] The image generating unit 20 includes a liquid crystal panel 22, a plurality of light-emitting elements 24A, 24B that provide backlight illumination from the rear side (i.e., the rear side of the device) of the liquid crystal panel 22, a substrate 26 on which the plurality of light-emitting elements 24A, 24B are mounted, a lens member 28 that controls the deflection of light emitted from the plurality of light-emitting elements 24A, 24B, a lens holder 30 that supports the lens member 28, and a heat sink 32 that supports the lens holder 30.

[0050] The liquid crystal panel 22 has a horizontally elongated rectangular outer shape, and is supported at its outer periphery by a lens holder 30 in a state where it is arranged along a vertical plane perpendicular to the front-rear direction of the device.

[0051] The light emitting elements 24A, 24B are all white light emitting diodes and are arranged in a vertical and horizontal grid pattern. Specifically, the light emitting elements 24A, 24B are arranged in four locations at equal intervals in the vertical direction and in six locations at equal intervals in the horizontal direction, for a total of 24 locations.

[0052] The multiple light-emitting elements 24A, 24B are configured such that the multiple light-emitting elements 24A located in the lower half are lit when the vehicle speed is in the low to medium speed range, and the multiple light-emitting elements 24B located in the upper half are lit when the vehicle speed is in the high speed range.

[0053] The substrate 26 is supported at its rear surface by a heat sink 32 in a state in which the substrate 26 is arranged along a vertical plane perpendicular to the front-rear direction of the device so that the light emitting surfaces of the multiple light emitting elements 24A, 24B face the front direction of the device.

[0054] The lens member 28 is configured such that a plurality of convex lens portions 28A, 28B are formed on the front surface of a horizontally long rectangular plate-shaped portion arranged along a vertical plane perpendicular to the front-rear direction of the device. The plurality of convex lens portions 28A, 28B are formed at 24 locations so as to be located in the front vicinity of the plurality of light-emitting elements 24A, 24B, thereby deflecting the light emitted from each of the plurality of light-emitting elements 24A, 24B toward the front of the device. The lens member 28 is supported by a lens holder 30 at the outer peripheral edge of the plate-shaped portion. The lens holder 30 is supported by a heat sink 32 at its rear end surface.

[0055] The heat sink 32 is made of a metal material such as aluminum, and includes a main body 32A extending flat along a vertical plane perpendicular to the front-to-rear direction of the device, and a plurality of heat dissipation fins 32B extending from the main body 32A at intervals in the left-right direction toward the rear of the device.

[0056] The image generation unit 20 is configured to generate a display image (i.e., an image that serves as the basis for the virtual images PIC-A and PIC-B) on the liquid crystal panel 22 by deflecting and controlling the light emitted from the multiple light-emitting elements 24A and 24B using the lens member 28 and then causing the light to enter the liquid crystal panel 22.

[0057] The reflecting mirror 40 is supported by the first housing 52 so as to be rotatable about an axis Ax that extends in the left-right direction.

[0058] To achieve this, an actuator 70 for rotating the reflecting mirror 40 about the axis Ax is fixed to the first housing 52. This fixing is performed by fastening screws 72 to the bottom wall of the first housing 52 at tab-shaped mounting portions 70b formed at two locations on the actuator 70.

[0059] The reflecting mirror 40 has vertical flanges 46 formed so as to protrude from both left and right sides of the rear surface of the reflecting surface 40a (i.e., the surface on the front side of the device) toward the rear side, and a pair of left and right shafts 48L, 48R protruding outward in the left-right direction along the axis Ax are formed on the pair of left and right vertical flanges 46. The left shaft 48L (right side when viewed from the front of the device) is placed on a placement portion 52b formed on the inner surface of the peripheral wall portion 52a of the first housing 52, and the right shaft 48R is directly connected to the output shaft 70a of the actuator 70.

[0060] The mounting portion 52b has a substantially U-shaped mounting surface, and the second housing 54 is formed with an abutment portion (not shown) for abutting from above against the shaft portion 48L mounted on the mounting portion 52b to position the reflector 40.

[0061] The control unit 80 shown in FIG. 1 is configured to control the image generating unit 20 in accordance with the vehicle driving conditions.

[0062] That is, the control unit 80 is configured to control the display content of the liquid crystal panel 22 in the image generating unit 20 and the turning on and off of the plurality of light-emitting elements 24A, 24B based on information related to vehicle travel such as vehicle speed, gear position, video from an on-board camera, and vehicle position, as well as external information such as map data, weather, and time. The control unit 80 turns on the plurality of light-emitting elements 24A to form a virtual image PIC-A when the vehicle speed is in the low to medium speed range, and turns on the plurality of light-emitting elements 24B to form a virtual image PIC-B when the vehicle speed is in the high speed range.

[0063] FIG. 5 is a view taken in the direction of the arrow V in FIG. 4, showing the reflecting mirror 40 in detail.

[0064] As also shown in FIG. 5, the reflecting mirror 40 has an effective reflection area 42 that controls the reflection of light emitted from the image generating unit 20, and an outer circumferential edge area 44 that surrounds this effective reflection area 42 over its entire periphery.

[0065] The reflector 40 has an outer peripheral region 44 that is thicker than the effective reflection region 42, and is supported at the outer peripheral region 44 by a first housing 52 and a drive unit 70 that serve as a reflector support member. The effective reflective area 42 includes a first reflective area 42A for reflecting a display image formed on the liquid crystal panel 22 as an image that serves as the basis for the virtual image PIC-A, and a second reflective area 42B for reflecting a display image formed on the liquid crystal panel 22 as an image that serves as the basis for the virtual image PIC-B.

[0066] The first and second reflection areas 42A and 42B are both horizontally elongated rectangular reflection areas, with the first reflection area 42A located above the second reflection area 42B and the two areas partially overlapping each other. The first reflection area 42A is set to have a narrower left-right width than the second reflection area 42B.

[0067] The outer peripheral region 44 is formed to surround the effective reflection region 42 with a substantially constant width, but the left and right side portions 44a of the first reflection region 42A are set to be wider than the other general regions. A pair of left and right 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.

[0068] Next, the operation of this embodiment will be described.

[0069] The image projection device 10 of this embodiment is configured to project virtual images PIC-A and PIC-B on the image display section 106 by reflecting the light emitted from the image generating unit 20 by the reflecting mirror 40. The reflecting mirror 40 has an effective reflection area 42 that controls the reflection of the light emitted from the image generating unit 20, and an outer peripheral edge area 44 that surrounds it all around. In addition, the outer peripheral edge area 44 of the reflecting mirror 40 is formed to be thicker than the effective reflection area 42, and is supported at the outer peripheral edge area 44 by the first housing 52 and the actuator 70, which serve as reflecting mirror support members, so that the following effects can be obtained.

[0070] That is, by configuring the outer peripheral region 44 to be thicker than the effective reflection region 42, it is possible to ensure the necessary rigidity without significantly increasing the weight of the reflecting mirror 40. This makes it possible to suppress deformation of the reflecting mirror 40 and maintain its optical function.

[0071] Furthermore, by configuring the first housing 52 and the actuator 70 to support the reflector 40 in the outer peripheral region 44, it is possible to prevent deformations that would adversely affect the function of the reflector 40 from occurring in the effective reflection region 42.

[0072] Thus, according to this embodiment, in an image projection device configured to project display images generated by the image generation unit 20 onto the image display section 106 as virtual images PIC-A and PIC-B, even if the reflector 40 for reflecting the light emitted from the image generation unit 20 toward the image display section 106 is enlarged, a lightweight and inexpensive configuration can be realized while ensuring the optical function.

[0073] In this embodiment, the image display unit 106 is configured to project a virtual image PIC-A (first virtual image) on the lower region 106A and a virtual image PIC-B (second virtual image) on the upper region 106B. To achieve this, the effective reflection area 42 of the reflecting mirror 40 is provided with a first reflection area 42A for reflecting the display image that is the source of the virtual image PIC-A and a second reflection area 42B for reflecting the display image that is the source of the virtual image PIC-B. In addition, the first reflection area 42A is set above the second reflection area 42B as an area narrower in left-right width than the second reflection area 42B, and the reflecting mirror 40 is supported by the first housing 52 and the actuator 70 at both left and right side portions 44a of the first reflection area 42A in the outer peripheral area 44, so that the following effects can be obtained.

[0074] That is, when the effective reflection area 42 is configured in this manner such that the first reflection area 42A is set above the second reflection area 42B and has a narrower left-right width than the second reflection area 42B, it is easy to ensure space for arranging a structure for supporting the reflector 40 on both left and right sides of the first reflection area 42A in the outer circumferential edge area 44. Therefore, by effectively utilizing this space, it is possible to ensure sufficient rigidity of the reflector 40 supported by the first housing 52 and the actuator 70.

[0075] Furthermore, the reflecting mirror 40 of this embodiment is configured as a concave mirror having an outer shape of a horizontally elongated rectangle, and since it is difficult to maintain the surface precision of the effective reflecting area 42, it is even more effective to adopt the configuration of this embodiment.

[0076] Furthermore, the reflector 40 of this embodiment is supported so as to be rotatable about an axis Ax extending in the left-right direction relative to the first housing 52 and the actuator 70, and since this configuration makes it difficult to maintain the surface accuracy of the effective reflecting area 42, it is even more effective to adopt the configuration of this embodiment.

[0077] In the above embodiment, the image generating unit 20 has been described as having 12 light-emitting elements 24A and 12 light-emitting elements 24B, but it is also possible to configure the image generating unit 20 to have any other number of light-emitting elements 24A, 24B.

[0078] In the above embodiment, the image display unit 106 is described as being set on the inner surface of the front window 102, but it is also possible to configure the image display unit using a translucent plate or the like arranged on the inside of the vehicle compartment of the front window 102.

[0079] In the above embodiment, the image projection device 10 has been described as being an in-vehicle head-up display, but it may also be used for other purposes.

[0080] Next, a modification of the above embodiment will be described.

[0081] First, a first modification of the above embodiment will be described.

[0082] FIG. 6 is a diagram similar to FIG. 2, showing the configuration of this modified example.

[0083] The basic configuration of the image projection device according to this modification is similar to that of the above embodiment, but the contents of the control are partly different from those of the above embodiment.

[0084] That is, as shown in FIG. 6(a), when the vehicle speed is in the low to medium speed range, as in the above embodiment, a virtual image PIC-A is displayed as a first virtual image in the lower region 106A of the image display unit 106, and at that time, if necessary, a virtual image PIC-C different from the virtual image PIC-B of the above embodiment is displayed as a second virtual image in the upper region 106B.

[0085] Specifically, as shown in FIG. 6(b), in the event of an emergency, such as when a pedestrian or the like enters the road ahead of the vehicle, a virtual image PIC-C indicating the presence and direction of the pedestrian or the like is additionally displayed in the upper region 106B.

[0086] By adopting the configuration of this modified example, it is possible to further improve safety during vehicle travel.

[0087] In this modified example, it is of course possible to configure the vehicle to display a virtual image similar to the virtual image PIC-B of the above embodiment as a second virtual image in the upper region 106B when the vehicle speed reaches a high-speed range in a state in which no emergency has occurred.

[0088] Next, a second modification of the above embodiment will be described.

[0089] FIG. 7 is a view similar to FIG. 5, showing a reflector 240 of an image projection device according to this modified example.

[0090] Like the reflector 40 of the above embodiment, the reflector 240 of this modified example also has an effective reflection area 242 and an outer peripheral region 244 surrounding it all around, and the outer peripheral region 244 is configured to be thicker than the effective reflection area 242, but the configuration of the outer peripheral region 244 is partially different from that of the above embodiment.

[0091] That is, in this modified example, the outer peripheral edge region 244 of the reflector 240 has a pair of left and right vertical flange portions 246 formed on both left and right sides 244a of the first reflecting area 42A, but differs from the above embodiment in that an annular rib 244b is formed on the outermost peripheral edge of this outer peripheral edge region 244, surrounding the entire effective reflecting area 242.

[0092] Even when the configuration of this modified example is adopted, substantially the same effects as those of the above embodiment can be obtained.

[0093] Furthermore, by configuring the reflector 240 in such a manner that an annular rib 244b is additionally formed in the outer peripheral region 244 as in this modified example, it becomes even easier to ensure the rigidity required for the reflector 240 in the outer peripheral region 244 while maintaining the optical function required for the reflector 240 in the effective reflection region 242.

[0094] Next, a third modification of the above embodiment will be described.

[0095] FIG. 8 is a diagram similar to FIG. 1, showing an image projection device 310 according to this modified example.

[0096] The basic configuration of this modified example is similar to that of the above embodiment, but differs from the above embodiment in that the light emitted from the image generating unit 320 is sequentially reflected by the first and second reflecting mirrors 340P, 340S toward the image display unit 106.

[0097] Accordingly, the configuration and arrangement of the image generating unit 320 differs from that of the above embodiment, and the configuration of the housing 350 also differs partially from that of the above embodiment.

[0098] That is, in this modified example, the first reflecting mirror 340P is disposed in the rear region of the internal space 12 and the second reflecting mirror 340S is disposed in the front region of the internal space 12, and the image generating unit 320 is supported by the first housing 352 in a position between and below the first reflecting mirror 340P and the second reflecting mirror 340S.

[0099] Similar to the image generating unit 20 of the above embodiment, the image generating unit 320 includes a liquid crystal panel 322, a plurality of light emitting elements 324A, 324B, a lens member 328, a lens holder 330, and a heat sink 332, and is disposed facing the first reflecting mirror 340P. Note that the image generating unit 320 has a smaller number of light emitting elements 324A, 324B and convex lens portions 328A, 328B of the lens member 328 than the image generating unit 20 of the above embodiment.

[0100] The second reflecting mirror 340S has an effective reflecting area 342 and an outer circumferential edge area 344 substantially similar to those of the reflecting mirror 40 of the above embodiment.

[0101] First reflecting mirror 340P is located diagonally above and behind image generating unit 320, and is configured to reflect light emitted from image generating unit 320 forward. Reflecting surface 340Pa of first reflecting mirror 340P has an outer shape of a horizontally elongated rectangle when viewed from the front of the device, with its horizontal cross-sectional shape being configured as a convex curve and its vertical cross-sectional shape being configured as a concave curve.

[0102] The first reflecting mirror 340P is configured to reflect the light emitted from the image generating unit 320 toward the first reflecting area 342A of the effective reflecting area 342 when the multiple light-emitting elements 324A are lit, and to reflect the light emitted from the image generating unit 320 toward the second reflecting area 342B of the effective reflecting area 342 when the multiple light-emitting elements 324B are lit.

[0103] Even when the configuration of this modified example is adopted, substantially the same effects as those of the above embodiment can be obtained.

[0104] In addition, after adopting a configuration in which the light emitted from the image generating unit 320 is sequentially reflected by the first and second reflecting mirrors 340P, 340S as in this modified example, it is also possible to adopt a configuration for the first reflecting mirror 340P that is configured to converge the light emitted from the image generating unit 320 on the rear side of the device relative to the second reflecting mirror 340S in the vertical direction.

[0105] The numerical values ​​shown as the specifications in the above embodiment and its modified examples are merely examples, and it goes without saying that these may be set to different values ​​as appropriate.

[0106] Furthermore, the present invention is not limited to the configurations described in the above embodiment and its modified examples, and various other modified configurations can be adopted. [Explanation of symbols]

[0107] 2 Driver 10, 310 Image projection device 12 Interior Space 20,320 Image Generation Unit 22, 322 LCD panel 24A, 24B, 324A, 324B Light emitting element 26 Substrate 28, 328 Lens parts 28A, 28B, 328A, 328B Convex lens part 30, 330 Lens holder 32, 332 Heat sink 32A Main unit 32B Heat dissipation fin 40, 240 reflector 40a, 340Pa reflective surface 42, 242, 342 Effective reflection area 42A, 342A 1st reflection area 42B, 342B 2nd reflective area 44, 244, 344 Outer perimeter area 44a, 244a Left and right side 46, 246 Vertical flange section 48L, 48R shaft part 50, 350 Housing 52, 352 First housing (reflector support member) 52a Peripheral wall part 52b Placement part 54 Second Housing 54a Top opening 54b Outer periphery flange 54c Light shielding piece 60 Translucent cover 70 Actuator (reflector support member) 70a Output shaft 70b Mounting part 72 Screw 80 Control Unit 100 vehicles 102 Front window 104 Steering Wheel 106 Image display unit 106A Lower area 106B Upper area 244b Circular rib 340P 1st reflector 340S 2nd reflector Ax axis PIC-A Virtual Image (First Virtual Image) PIC-B, PIC-C Virtual image (second virtual image) R optical path

Claims

1. An image projection device configured to project a display image generated by an image generating unit on an image display unit as a virtual image, a reflector that reflects the light emitted from the image generating unit toward the image display unit, and a reflector support member that supports the reflector, the reflecting mirror includes an effective reflection area that controls reflection of light emitted from the image generating unit, and an outer peripheral edge area that completely surrounds the effective reflection area, the outer peripheral region is formed to be thicker than the effective reflection region, The image projection device, wherein the reflector is supported at the outer peripheral region by the reflector support member.

2. the image projection device is configured to project a first virtual image in a lower region of the image display unit and a second virtual image in an upper region of the image display unit, The effective reflection area includes a first reflection area for reflecting a display image that is the basis of the first virtual image and a second reflection area for reflecting a display image that is the basis of the second virtual image, and the first reflection area is set above the second reflection area as an area having a narrower left-right width than the second reflection area, 2. The image projection device according to claim 1, wherein the reflector is supported by the reflector support members at both left and right sides of the first reflecting area in the outer peripheral area.

3. The effective reflection area is formed with a constant thickness, 3. The image projection device according to claim 1, wherein the outer peripheral area includes an annular rib formed so as to surround the entire effective reflection area.

4. 3. The image projection device according to claim 1, wherein the reflecting mirror is a concave mirror having an outer shape of a horizontally elongated rectangle.

5. 3. The image projection device according to claim 1, wherein the reflecting mirror is supported so as to be rotatable about an axis extending in the left-right direction relative to the reflecting mirror support member.

Images