Vehicular display device

Abstract

The present invention comprises a display unit (10), a plane mirror (20) that reflects display light from a display device (11), a first concave mirror (30) that reflects the reflected light of the plane mirror, and a second concave mirror (40) that reflects the reflected light of the first concave mirror and projects the reflected light from an emission port (70a) of an outer case onto a projection target part (Rwf). The outer case includes: a lower case (70A) that has an inlet port (70b) that causes the display light from the display device of the display unit fixed outside a compartment to enter the inside of the compartment, and that holds the plane mirror and the second concave mirror in the compartment and is fixed to a vehicle body; a lower cover (70B) that accommodates the display unit and is fixed to the lower case; and an upper case (70C) that has an outlet port, is fixed to the lower case, and clamps the first concave mirror together with the lower case. An inner case (80) is fixed to the lower case inside the compartment of the lower case, and clamps the plane mirror together with the lower case.

Description

Vehicle display device

[0001] The present invention relates to a display device for a vehicle.

[0002] Conventionally, vehicles are equipped with a vehicle display device that displays information to be provided to occupants in the vehicle cabin as a virtual image. This vehicle display device is a so-called head-up display device and includes a display unit that emits display information to be projected onto a projection target as display light, a reflecting member that reflects the display light emitted from the display unit and projects the display light onto the projection target, and a housing that accommodates these. This vehicle display device projects the display light reflected by the reflecting member onto the projection target outside the housing, allowing the occupants to view the display information corresponding to the projected display light as a virtual image. This type of vehicle display device is disclosed, for example, in Patent Document 1 listed below.

[0003] Japanese Patent Application Laid-Open No. 2020-148950

[0004] In a vehicle display device, the viewing distance can be extended by increasing the number of reflective optical components within the housing, thereby extending the optical path length of the optical components. For example, in the above-mentioned Patent Document 1, one plane mirror and two aspherical mirrors are arranged within the housing. However, in a vehicle display device, the more reflective optical components are used, the more difficult it may be to ensure the display quality of the virtual image unless the positional accuracy of the reflective optical components is improved.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a vehicle display device that can extend the viewing distance while ensuring quality.

[0006] The present invention provides a vehicle interior lighting system comprising an outer case, an inner case disposed within the outer case, a display unit configured to emit display information into the outer case as display light to be viewed as a virtual image by occupants within the vehicle cabin, a plane mirror configured to reflect the display light emitted from a display of the display unit within the outer case, a first concave mirror configured to reflect the display light reflected by the plane mirror within the outer case, and a second concave mirror configured to reflect the display light reflected by the first concave mirror within the outer case and project the display light from an emission port of the outer case onto a projection target within the vehicle cabin, wherein the outer case is configured to project the display light onto an projection target within the vehicle cabin. The vehicle comprises a lower case having an entrance port for allowing the display light emitted from the display of the fixed display unit to enter the interior of the vehicle, and holding the plane mirror and the second concave mirror inside the vehicle, and being fixed to the vehicle body; a lower cover that houses the display unit outside the lower case and is fixed to the lower case; and an upper case having the exit port, being fixed to the lower case, and sandwiching the first concave mirror between itself and the lower case, wherein the inner case is fixed to the lower case inside the lower case and sandwiches the plane mirror between itself and the lower case.

[0007] The vehicle display device according to the present invention uses three reflective members (a plane mirror, a first concave mirror, and a second concave mirror), which allows for high magnification and an extended viewing distance by extending the optical path length within the housing (outer case and inner case). However, the long optical path length of this vehicle display device makes it difficult to ensure the display quality of the virtual image. However, the vehicle display device according to the present invention uses aspherical mirrors (free-form mirrors) for two of the three reflective members (the first concave mirror and the second concave mirror), thereby ensuring the display quality of the virtual image. Furthermore, in the vehicle display device according to the present invention, the plane mirror is sandwiched between the lower case and the inner case of the outer case, the first concave mirror is sandwiched between the lower case and the upper case of the outer case, and the second concave mirror is held by the lower case. That is, in the vehicle display device according to the present invention, three reflective members (the plane mirror, the first concave mirror, and the second concave mirror) are all held in a single lower case with the three reflective members interposed therebetween. Therefore, this vehicle display device can minimize the number of design tolerances involved in the relative positional relationships between the three reflective members (the plane mirror, the first concave mirror, and the second concave mirror), thereby minimizing variations between the reflective members due to stack-up tolerances. Therefore, the vehicle display device according to the present invention can improve the positional accuracy between the plane mirror and the first concave mirror, and also improve the positional accuracy between the first concave mirror and the second concave mirror, thereby creating a highly accurate optical path within the housing (outer case, inner case), thereby ensuring the display quality of virtual images. Furthermore, because the vehicle display device according to the present invention has its lower case fixed to the vehicle body, the positional accuracy from this fixing point to each reflective member (the plane mirror, the first concave mirror, and the second concave mirror) can be improved, and therefore the positional accuracy between the second concave mirror and the projection target can also be improved. Therefore, the vehicle display device according to the present invention can improve the accuracy of the optical path not only inside the housing (outer case, inner case) but also outside the housing, thereby ensuring the display quality of the virtual image. In this way, the vehicle display device according to the present invention can extend the viewing distance while ensuring the display quality of the virtual image.

[0008] FIG. 1 is a schematic diagram showing a vehicle display device according to an embodiment. FIG. 2 is a perspective view showing the vehicle display device according to an embodiment. FIG. 3 is an exploded perspective view showing the vehicle display device according to an embodiment, with the outer case partially disassembled. FIG. 4 is an exploded perspective view of the lower case, lower cover, and display unit in the outer case. FIG. 5 is an exploded perspective view showing three reflective members together with the inner case. FIG. 6 is a perspective view showing the second concave mirror and its related components. FIG. 7 is an exploded perspective view showing the first inner case together with the display unit and the plane mirror. FIG. 8 is an exploded perspective view of the first inner case together with the display unit and the plane mirror, viewed from a different angle. FIG. 9 is an exploded perspective view showing the second inner case together with the first concave mirror and the second concave mirror.

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a vehicle display device according to the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention is not limited to the embodiment.

[0010] [Embodiment] One embodiment of a vehicle display device according to the present invention will be described with reference to Figs.

[0011] 1 to 3, reference numeral 1 denotes a vehicle display device according to this embodiment. The vehicle display device 1 is a so-called head-up display device that displays a virtual image of information to be provided to an occupant in the cabin of a vehicle (such as an automobile). The vehicle display device 1 projects display light relating to the display information onto a projection surface Rwf, such as a windshield, within the cabin, and reflects the display light from the projection surface Rwf toward the occupant, thereby allowing the occupant to visually recognize a virtual image of the display information (FIG. 1).

[0012] The vehicular display device 1 includes a display unit 10 that emits display information as display light into an outer case 70 (FIGS. 1 and 4), which is displayed as a virtual image to be viewed by passengers in the vehicle cabin. The display unit 10 includes a backlight (not shown) and a light-transmitting, plate-like display 11. Light irradiated from the backlight onto the display 11 is transmitted through the display 11, and is emitted from the display 11 as display light for display information (FIGS. 1 and 4). For example, a light-transmitting, TFT liquid crystal (thin film transistor liquid crystal) display or the like is used as the display 11.

[0013] Furthermore, the vehicle display device 1 includes a plurality of reflecting members that reflect the display light emitted from the display 11 of the display unit 10 inside the outer case 70 and project the display light onto a projection area Rwf inside the vehicle cabin from an emission port 70a of the outer case 70. The vehicle display device 1 includes a plane mirror 20, a first concave mirror 30, and a second concave mirror 40 as its reflecting members (FIGS. 1, 3, and 5).

[0014] The plane mirror 20 reflects the display light emitted from the display 11 of the display unit 10 inside the outer case 70. The first concave mirror 30 reflects the display light reflected by the plane mirror 20 inside the outer case 70. The second concave mirror 40 reflects the display light reflected by the first concave mirror 30 inside the outer case 70, and projects the display light from an exit port 70a of the outer case 70 onto a projection area Rwf inside the vehicle cabin. The first concave mirror 30 and the second concave mirror 40 are magnifying mirrors that magnify and reflect the incident display light. For example, the first concave mirror 30 and the second concave mirror 40 are aspherical mirrors (free-form mirrors) whose reflective surfaces are concave into an aspherical shape (free-form shape).

[0015] The vehicle display device 1 includes a drive unit 50 that rotates the second concave mirror 40 to change the imaging position (display position) of the virtual image (see FIGS. 1, 5, and 6). The second concave mirror 40 is rotated around a rotation axis that extends in the vehicle width direction, thereby changing the imaging position (display position) of the virtual image in the vertical direction of the vehicle. The drive unit 50 includes a motor 51 as a drive source, a power transmission mechanism 52 that operates with the output of the motor 51, and a rotary shaft 53 that rotates the second concave mirror 40 around its axis with the output of the motor 51 input via the power transmission mechanism 52, with the axial direction of the vehicle width (see FIGS. 1 and 6).

[0016] The power transmission mechanism 52 may be one that directly applies a rotational torque corresponding to the output torque of the motor 51 to the rotation shaft 53. Alternatively, the power transmission mechanism 52 may be a power conversion mechanism that converts the output torque of the motor 51 into a linear force and applies this linear force to the second concave mirror 40, thereby rotating the rotation shaft 53 that is positioned eccentrically with respect to the input point of the linear force. The rotation shaft 53 may be provided on the second concave mirror 40, or may be provided on a holding member that holds the second concave mirror 40. The rotation shaft 53 is formed in a cylindrical or cylindrical shape.

[0017] The illustrated power transmission mechanism 52 is a power conversion mechanism that converts the output torque of the motor 51 into a linear force, and includes an input unit 52a, to which the linear force is input, on the second concave mirror 40 side ( FIGS. 5 and 6 ). In this example, the second concave mirror 40 is held by a holding member 41 ( FIGS. 3 , 5 , and 6 ). The holding member 41 is provided with a pair of coaxial rotation shafts 53 and the input unit 52a, which is positioned eccentrically relative to the pair of rotation shafts 53.

[0018] This drive unit 50 rotates the second concave mirror 40 around the rotation axis 53, thereby changing the incident angle of the display light reflected from the first concave mirror 30 onto the second concave mirror 40, and also changing the emission angle of the display light reflected from the second concave mirror 40 toward the projection surface Rwf. By changing the emission angle of the display light from the second concave mirror 40 toward the projection surface Rwf, this drive unit 50 changes the imaging position (display position) of a virtual image related to the display light in the vertical direction of the vehicle.

[0019] The display light projected onto the projection area Rwf is reflected from the projection area Rwf to the eye point EP or the eye box EB, where it is visually recognized by the occupant as a virtual image (see FIG. 1). The eye point EP indicates the position of the occupant's eyes in the vehicle cabin. The eye box EB indicates the range of the eye point EP where the virtual image can be viewed.

[0020] The projection target Rwf refers to the windshield (here, the front windshield Wf) itself or a portion thereof (FIG. 1). The projection target Rwf may also be formed as a half mirror that receives display light from the second concave mirror 40 on a reflective surface, reflects it toward the eye point EP or the eye box EB, and emits light from outside the vehicle toward the occupants. For example, the projection target Rwf as a half mirror may be formed as a semi-transparent film conforming to the curved shape of the windshield (front windshield Wf) and attached to the interior wall surface of the windshield with an adhesive. The projection target Rwf as a half mirror may also be formed as a semi-transparent film conforming to the curved shape of the windshield (front windshield Wf) and sealed together with an intermediate film inside the laminated windshield. The projection target Rwf as a half mirror may also be a semi-transparent coating applied by painting or the like to the interior wall surface of the windshield (front windshield Wf). The projection target portion Rwf may be a combiner that covers the front windshield Wf from the inside of the vehicle compartment.

[0021] The vehicle display device 1 includes a control unit 60 (FIG. 1) that controls the operation of the display unit 10 and the drive unit 50. The control unit 60 controls, for example, the display information (display light) of the display unit 10. The control unit 60 also controls the output of the motor 51 to rotate the second concave mirror 40.

[0022] The vehicle display device 1 includes an outer case 70 and an inner case 80 disposed inside the outer case 70 (see FIGS. 2 and 3). In the vehicle display device 1, the housing is formed by the outer case 70 and the inner case 80.

[0023] In addition to the inner case 80, the outer case 70 accommodates at least the display unit 10, the plane mirror 20, the first concave mirror 30, the second concave mirror 40, and part or all of the drive unit 50. The outer case 70 emits display light from the display 11 of the display unit 10 indoors, and then transmits the reflected display light to the second concave mirror 40 and emits it outdoors toward the projection surface Rwf. The outer case 70 has an opening (hereinafter referred to as the "emission port") 70a through which the display light reflected by the second concave mirror 40 is emitted outdoors (FIGS. 2 and 3). The inner case 80 forms an optical path within the outer case 70 between the display 11 of the display unit 10 and the emission port 70a of the outer case 70.

[0024] The outer case 70 has an opening (hereinafter referred to as the "incident port") 70b that allows display light emitted from the display 11 of the display unit 10 fixed to the outside of the vehicle to enter the vehicle interior, and is equipped with a lower case 70A that holds the plane mirror 20 and the second concave mirror 40 inside the vehicle and is fixed to the vehicle body, and a lower cover 70B that houses the display unit 10 outside the lower case 70A and is fixed to the lower case 70A (Figures 2 to 4).

[0025] The display unit 10 is disposed outside the lower case 70A with the display 11 facing the light entrance 70b and facing the interior of the lower case 70A. The display unit 10 is fixed to the lower case 70A with screws on the outside of the lower case 70A. The lower cover 70B houses the display unit 10 in a manner that covers the exterior of the lower case 70A and is fixed to the lower case 70A with screws.

[0026] The lower case 70A has an opening (hereinafter referred to as the "accommodation opening") 70c that faces upward of the vehicle (see FIGS. 3 and 4). The plane mirror 20, the second concave mirror 40, part or all of the drive unit 50, and the inner case 80 are accommodated in the interior of the lower case 70A through the accommodation opening 70c.

[0027] In this lower case 70A, the plane mirror 20 inside the chamber is sandwiched between the first inner case 80A (described later). In this lower case 70A, the peripheral edge of the first concave mirror 30 is placed on the peripheral edge of the accommodation opening 70c, and the first concave mirror 30 is sandwiched between the lower case 70A and the upper case 70C (described later). In this lower case 70A, the rotating shaft 53 on the second concave mirror 40 side is held inside the chamber via a bearing part 54 (FIGS. 5 and 6). The bearing part 54 is formed or configured to rotatably support the rotating shaft 53 and is fixed to a bearing fixing part 71 (FIG. 4) inside the chamber of the lower case 70A. Here, the bearing part 54 is fixed to the bearing fixing part 71 inside the chamber of the lower case 70A with screws. The drive unit 50 includes a bearing part 54 for each rotating shaft 53.

[0028] An outer wall surface of the lower case 70A is provided with a vehicle body fixing portion 72 for fixing to the vehicle body (FIGS. 2 to 4). The lower case 70A is fixed to the vehicle body at the vehicle body fixing portion 72 with screws.

[0029] The outer case 70 further includes an upper case 70C having an exit port 70a, fixed to the lower case 70A, and sandwiching the first concave mirror 30 between the upper case 70C and the lower case 70A, and a transparent cover 70D that covers the exit port 70a (Figures 2 and 3).

[0030] The upper case 70C covers the plane mirror 20, the second concave mirror 40, part or all of the drive unit 50, and the inner case 80 housed in the lower case 70A from the outside, and closes the accommodation opening 70c of the lower case 70A by sandwiching the peripheral edge of the first concave mirror 30 placed on the peripheral edge of the accommodation opening 70c. The upper case 70C is fixed to the lower case 70A with screws while closing the accommodation opening 70c. The upper case 70C has an emission opening 70a above the vehicle. The cover 70D is attached to the upper case 70C in a manner that closes the emission opening 70a.

[0031] The vehicular display device 1 is housed in an instrument panel Pi in a vehicle cabin with its cover 70D exposed (FIG. 1). In this vehicular display device 1, display light reflected by the second concave mirror 40 is emitted from the cover 70D to the outside of the outer case 70 and projected onto a projection target Rwf located beyond the second concave mirror 40, where the display light is reflected by the projection target Rwf toward the eye point EP or the eye box EB.

[0032] The inner case 80 is fixed to the lower case 70A within the chamber of the lower case 70A. The inner case 80 sandwiches the plane mirror 20 between itself and the lower case 70A. The inner case 80 includes a first inner case 80A that is fixed to the lower case 70A within the chamber of the lower case 70A and sandwiches the plane mirror 20 within the chamber of the lower case 70A between itself and the lower case 70A, and a second inner case 80B that is fixed to the lower case 70A within the chamber of the lower case 70A (FIGS. 3 and 5).

[0033] The first inner case 80A has a first internal space 81a (FIGS. 5, 7, and 8) that defines an optical path between the display 11 and the plane mirror 20 and an optical path between the plane mirror 20 and the first concave mirror 30. The first inner case 80A also has a first opening 81b, a second opening 81c, and a third opening 81d (FIGS. 5, 7, and 8).

[0034] The first opening 81b is disposed opposite the display 11 and allows display light emitted from the display 11 to enter the first internal space 81a. The first opening 81b is disposed opposite the light entrance 70b of the lower case 70A inside the lower case 70A.

[0035] The second opening 81c has an opening periphery that sandwiches the periphery of the plane mirror 20 between itself and the lower case 70A, exposing the plane mirror 20 to the first internal space 81a. Therefore, the second opening 81c allows the display light from the display 11 that has entered the first internal space 81a to be incident on the plane mirror 20, and the display light reflected by the plane mirror 20 to be emitted toward the first concave mirror 30.

[0036] The third opening 81d allows the display light reflected by the plane mirror 20 to exit the first internal space 81a toward the first concave mirror 30.

[0037] The first inner case 80A is fixed to the lower case 70A with screws, with the plane mirror 20 sandwiched between the first inner case 80A and the lower case 70A.

[0038] The second inner case 80B has a second internal space 82a (FIGS. 5 and 9) that forms an optical path between the plane mirror 20 and the first concave mirror 30, an optical path between the first concave mirror 30 and the second concave mirror 40, and an optical path between the second concave mirror 40 and the projection target Rwf. The second inner case 80B has a first opening 82b, a second opening 82c, a third opening 82d, and a fourth opening 82e (FIGS. 5 and 9).

[0039] The first opening 82b is disposed opposite the third opening 81d of the first inner case 80A, so that the first opening 82b allows the display light reflected by the plane mirror 20 toward the first concave mirror 30 to enter the second internal space 82a.

[0040] The second opening 82c is disposed opposite the first concave mirror 30. This allows the second opening 82c to allow the display light from the plane mirror 20 that has entered the second internal space 82a to be incident on the first concave mirror 30, and also allows the display light reflected by the first concave mirror 30 to be emitted toward the second concave mirror 40.

[0041] The third opening 82d is disposed opposite the second concave mirror 40. This allows the third opening 82d to allow the display light reflected by the first concave mirror 30 to be incident on the second concave mirror 40, and to allow the display light reflected by the second concave mirror 40 to be emitted toward the projection portion Rwf.

[0042] The fourth opening 82e is disposed opposite the light exit port 70a of the upper case 70C and the cover 70D, and emits the display light reflected by the second concave mirror 40 out of the second internal space 82a toward the projection portion Rwf.

[0043] The second inner case 80B is fixed to the lower case 70A with screws.

[0044] As described above, the vehicle display device 1 of this embodiment uses three reflective members (the plane mirror 20, the first concave mirror 30, and the second concave mirror 40), which increases the magnification of the virtual image display and also increases the optical path length within the housing (the outer case 70 and the inner case 80), thereby extending the viewing distance. On the other hand, since the vehicle display device 1 requires a long optical path length, it becomes difficult to ensure the display quality of the virtual image.

[0045] However, the vehicle display device 1 of this embodiment uses aspherical mirrors (free-form mirrors) for two of its three reflective members (plane mirror 20, first concave mirror 30, second concave mirror 40), so the display quality of the virtual image can be ensured.

[0046] Furthermore, in the vehicle display device 1 of this embodiment, the plane mirror 20 is sandwiched between the lower case 70A of the outer case 70 and the first inner case 80A of the inner case 80, the first concave mirror 30 is sandwiched between the lower case 70A and the upper case 70C of the outer case 70, and the second concave mirror 40 is held in the lower case 70A via the bearing part 54. That is, in the vehicle display device 1 of this embodiment, the three reflective members (the plane mirror 20, the first concave mirror 30, and the second concave mirror 40) are all held in the single lower case 70A with the three reflective members interposed therebetween. Therefore, this vehicle display device 1 can minimize the number of design tolerances involved in the relative positional relationships of the three reflective members (the plane mirror 20, the first concave mirror 30, and the second concave mirror 40), and can minimize variations between the reflective members due to stack-up tolerances. Therefore, the vehicle display device 1 of this embodiment can improve the positional accuracy between the plane mirror 20 and the first concave mirror 30, and can also improve the positional accuracy between the first concave mirror 30 and the second concave mirror 40, and can create a highly accurate optical path within the housing (outer case 70, inner case 80), thereby ensuring the display quality of the virtual image.

[0047] Furthermore, since the vehicle display device 1 of this embodiment has its lower case 70A fixed to the vehicle body, the positional accuracy from this fixing point to each of the reflecting members (the plane mirror 20, the first concave mirror 30, and the second concave mirror 40) can be improved, and accordingly, the positional accuracy between the second concave mirror 40 and the projection target Rwf can also be improved. Therefore, the vehicle display device 1 of this embodiment can increase the accuracy of the optical path not only inside the housing (the outer case 70 and the inner case 80) but also to the outside of the housing, thereby ensuring the display quality of the virtual image.

[0048] In this way, the vehicle display device 1 of this embodiment can extend the viewing distance while ensuring the display quality of the virtual image.

[0049] Furthermore, the vehicle display device 1 of this embodiment employs a two-part structure for the inner case 80, which forms the optical path, consisting of a first inner case 80A and a second inner case 80B. Therefore, compared to a single-component inner case, the vehicle display device 1 of this embodiment offers greater design freedom for the optical path shape and improved moldability. Furthermore, compared to a single-component inner case, the vehicle display device 1 of this embodiment allows the first inner case 80A and the second inner case 80B, which are smaller in size, to be assembled separately, thereby reducing aggressiveness, such as strong interference, against the three reflective members (the plane mirror 20, the first concave mirror 30, and the second concave mirror 40) during assembly. Therefore, the vehicle display device 1 can improve assembly workability.

[0050] REFERENCE SIGNS LIST 1 Vehicle display device 10 Display unit 11 Display 20 Plane mirror 30 First concave mirror 40 Second concave mirror 70 Outer case 70A Lower case 70B Lower cover 70C Upper case 70a Light exit port 70b Light entrance port 80 Inner case 80A First inner case 80B Second inner case 81a First internal space 81b First opening 81c Second opening 81d Third opening 82a Second internal space 82b First opening 82c Second opening 82d Third opening 82e Fourth opening Rwf Projected portion

Claims

1. An apparatus comprising: an outer case; an inner case disposed within the outer case; a display unit that emits display information into the outer case as display light to be viewed as a virtual image by occupants within the vehicle cabin; a plane mirror that reflects the display light emitted from a display of the display unit within the outer case; a first concave mirror that reflects the display light reflected by the plane mirror within the outer case; and a second concave mirror that reflects the display light reflected by the first concave mirror within the outer case and projects the display light from an emission port of the outer case onto a projection target within the vehicle cabin, the outer case comprises a lower case having an entrance port through which the display light emitted from the display of the display unit fixed to the outside of the vehicle compartment enters the vehicle compartment, and which holds the plane mirror and the second concave mirror inside the vehicle compartment and is fixed to the vehicle body; a lower cover that houses the display unit outside the lower case and is fixed to the lower case; and an upper case having the exit port, which is fixed to the lower case and sandwiches the first concave mirror between itself and the lower case; and the inner case is fixed to the lower case inside the vehicle compartment and sandwiches the plane mirror between itself and the lower case.

2. The vehicle display device according to claim 1, wherein the inner case forms an optical path between the display and the light exit port.

3. The inner case comprises a first inner case fixed to the lower case within the chamber of the lower case and sandwiching the plane mirror within the chamber of the lower case between the first inner case and the lower case, and a second inner case fixed to the lower case within the chamber of the lower case, the first inner case is formed with a first internal space forming an optical path between the display and the plane mirror and an optical path between the plane mirror and the first concave mirror; a first opening disposed opposite the display and allowing the display light emitted from the display to enter the first internal space; a second opening having an opening peripheral portion that sandwiches a peripheral portion of the plane mirror between itself and the lower case, allowing the display light from the display that has entered the first internal space to enter the plane mirror and to exit the display light reflected by the plane mirror toward the first concave mirror; and a third opening that allows the display light reflected by the plane mirror to exit the first internal space toward the first concave mirror, the second inner case is provided with a second internal space forming an optical path between the plane mirror and the first concave mirror, an optical path between the first concave mirror and the second concave mirror, and an optical path between the second concave mirror and the projection target; a first opening arranged opposite the third opening of the first inner case and allowing the display light reflected by the plane mirror toward the first concave mirror to enter the second internal space; and a first opening arranged opposite the first concave mirror and allowing the display light from the plane mirror that entered the second internal space to enter the first concave mirror.

3. The vehicle display device according to claim 1, further comprising: a second opening that emits the display light reflected by the first concave mirror toward the second concave mirror; a third opening that is disposed opposite the second concave mirror and that allows the display light reflected by the first concave mirror to enter the second concave mirror and emit the display light reflected by the second concave mirror toward the projection target; and a fourth opening that is disposed opposite the emission opening and that emits the display light reflected by the second concave mirror to outside the second internal space toward the projection target.

Images