Vehicle display device

Abstract

A vehicle display device according to the present invention comprises: a housing; a display unit that emits, as display light into the housing, display information to be visually recognized as a virtual image by an occupant in a cabin; a plurality of reflective members that reflect the display light emitted from the display of the display unit in the housing; a holding member (45) molded of a high-rigidity material having higher rigidity than a movable reflective member (40), which is one of the plurality of reflective members, and holding the movable reflective member (40) from the rear surface on the back side of a display-light reflection surface (40a); a bezel member (46) that covers an outer peripheral edge of the reflection surface (40a) of the movable reflective member (40) and sandwiches the movable reflective member (40) with the holding member (45); and a drive unit (50) that rotates the movable reflective member (40) about the axis of a rotary shaft (53) of the holding member (45) to change the display position of the virtual image.

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 houses these components. 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. Here, this vehicle display device can perform adjustment control of the virtual image display position, which changes the imaging position (display position) of the virtual image by controlling the rotation of the reflecting member. For example, the vehicle display devices described in the following Patent Documents 1 to 3 hold the reflecting member from the back side with a holding member, and the holding member is provided with a rotation axis.

[0003] JP 2010-208565 A JP 2019-109304 A JP 2023-059966 A

[0004] In vehicle display devices, the reflecting member is enlarged to increase the magnification of the virtual image display. However, in vehicle display devices, the increase in mass due to the enlargement of the reflecting member increases the load on the rotation axis, which may cause fluctuations in the virtual image display. Furthermore, in vehicle display devices, the enlargement of the reflecting member may cause distortion in the virtual image display.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a vehicle display device that can ensure the display quality of a virtual image.

[0006] The present invention is characterized by comprising a housing, a display unit that emits display information into the housing as display light to be viewed as a virtual image by occupants in the vehicle cabin, one reflective member or multiple reflective members that reflect the display light emitted from the display of the display unit within the housing, a holding member that is a movable reflective member of the one reflective member or one of the multiple reflective members and is molded from a high-rigidity material that is more rigid than the movable reflective member and holds the movable reflective member from the back side behind the reflective surface of the display light, a bezel member that covers the outer peripheral edge of the reflective surface of the movable reflective member and clamps the movable reflective member between itself and the holding member, and a drive unit that rotates the movable reflective member around the rotation axis of the holding member to change the display position of the virtual image.

[0007] The vehicle display device according to the present invention holds the movable reflective member from the back side with a holding member, and the holding member is provided with a rotation axis. Therefore, compared to a vehicle display device with a rotation axis provided on the movable reflective member, this vehicle display device can suppress deformation of the movable reflective member even if the load on the rotation axis increases due to an increase in mass associated with an increase in the size of the movable reflective member. Therefore, the vehicle display device according to the present invention can suppress distortion and shaking of the virtual image display even if the movable reflective member is enlarged. Furthermore, the holding member is molded from a high-rigidity material that is more rigid than the movable reflective member. Therefore, this vehicle display device can suppress deformation of the holding member and, therefore, suppress deformation of the movable reflective member. Therefore, the vehicle display device according to the present invention can suppress distortion and shaking of the virtual image display even if the movable reflective member is enlarged. Furthermore, the vehicle display device according to the present invention covers the outer peripheral edge of the reflective surface of the movable reflective member with a bezel member. Therefore, even if distortion occurs at the outer peripheral edge of the movable reflective member during manufacturing, the vehicle display device according to the present invention can hide this distortion, thereby suppressing distortion at the outer peripheral edge of the virtual image display. In this way, the vehicle display device according to the present invention can ensure 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 a perspective view showing the second concave mirror. FIG. 8 is a perspective view showing a holding member. FIG. 9 is a perspective view showing a bezel member. FIG. 10 is an exploded perspective view showing the first inner case together with the display unit and the plane mirror. FIG. 11 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. 12 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 vehicle display device 1 includes a display unit 10 that emits display information as display light into a housing (FIGS. 1 and 4) to be viewed as a virtual image by a vehicle occupant. 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 and 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 one or more reflective members that reflect the display light emitted from the display 11 of the display unit 10 within the housing. In the vehicle display device 1, the one or one of the reflective members is a movable reflective member that rotates within the housing. The vehicle display device 1 shown here includes multiple reflective members that reflect the display light emitted from the display 11 within the housing and project the display light from an opening in the housing (a light exit 70a of an outer case 70 described below) onto a projection area Rwf within the vehicle cabin. The vehicle display device 1 includes a plane mirror 20, a first concave mirror 30, and a second concave mirror 40 as the multiple reflective members, and the second concave mirror 40 is configured as a movable reflective member (see FIGS. 1, 3, and 5).

[0014] The plane mirror 20 reflects the display light emitted from the display 11 of the display unit 10 within the housing. The first concave mirror 30 reflects the display light reflected by the plane mirror 20 within the housing. The second concave mirror 40 reflects the display light reflected by the first concave mirror 30 within the housing, and projects the display light from an opening in the housing (the light exit 70a of the outer case 70) onto a projection area Rwf within 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 may be aspherical mirrors (free-form mirrors) whose reflective surfaces are recessed into an aspherical shape (free-form shape).

[0015] The vehicle display device 1 includes a holding member 45 that holds the movable reflecting member (second concave mirror 40) from the rear surface 40b behind the display light reflecting surface 40a (FIGS. 6 to 8). The holding member 45 is molded from a highly rigid material that is more rigid than the movable reflecting member (second concave mirror 40). For example, in this example, the movable reflecting member (second concave mirror 40) includes a base plate (not shown) molded from a synthetic resin material, and the holding member 45 is molded from a metal material that is more rigid than the synthetic resin material.

[0016] The vehicle display device 1 also includes a bezel member 46 that covers the outer peripheral edge 40c of the reflective surface 40a of the movable reflective member (second concave mirror 40) and sandwiches the movable reflective member (second concave mirror 40) between itself and a holding member 45 (see FIGS. 6, 7, and 9). During manufacturing of the movable reflective member (second concave mirror 40), distortion may occur at the outer peripheral edge 40c. By covering and concealing the outer peripheral edge 40c with the bezel member 46, the vehicle display device 1 can suppress distortion at the outer peripheral edge of the virtual image display. The bezel member 46 is molded from, for example, a synthetic resin material.

[0017] The movable reflecting member (second concave mirror 40) shown here has a main body portion (hereinafter referred to as the "mirror body") 41a formed in a rectangular, aspherical shape (free-form surface shape) (see FIGS. 6 and 7). The movable reflecting member (second concave mirror 40) has a mirror body portion 41a with a reflective surface (i.e., a mirror surface) 40a and a back surface 40b. The outer peripheral edge 40c of the reflective surface 40a of the mirror body portion 41a is covered with a bezel member 46. The movable reflecting member (second concave mirror 40) shown here has clamped portions 41b that protrude from three sides of the mirror body portion 41a and are clamped between a holding member 45 and the bezel member 46 (see FIG. 7). Here, the mirror body portion 41a has plate-shaped clamped portions 41b on two sides located in the vehicle width direction and one side located above the vehicle.

[0018] The holding member 45 shown here has a main body portion 45a formed in a rectangular aspherical shape (free-form surface shape) and disposed opposite the rear surface 40b of the movable reflecting member (second concave mirror 40) (FIG. 8). The holding member 45 shown here has clamping portions 45b that protrude from three sides of the main body portion 45a and clamp the clamped portion 41b of the movable reflecting member (second concave mirror 40) between the main body portion 45a and the bezel member 46 (FIG. 8). Here, the main body portion 45a has clamping portions 45b on two sides located in the vehicle width direction and one side located above the vehicle.

[0019] It is desirable to attach the center portion of the back surface 40b of the movable reflecting member (second concave mirror 40) to the holding member 45 with a resin adhesive (not shown). This prevents deformation of the center portion of the movable reflecting member (second concave mirror 40) when an external input is transmitted to the holding member 45 or when the output of a motor 51 (described later) is transmitted to the holding member 45, thereby suppressing distortion and shaking of the virtual image display. For example, the center portion of the back surface 40b of the movable reflecting member (second concave mirror 40) is attached to the center portion of the main body portion 45a of the holding member 45 with a resin adhesive. The main body portion 45a shown here has weight reduction cutouts at multiple locations except for the center portion, and a rib is erected on the back surface opposite the front surface facing the second concave mirror 40 to increase rigidity.

[0020] The bezel member 46 shown here has a square-ring-shaped main body portion (hereinafter referred to as a "frame body portion") 46a that covers the outer peripheral edge portion 40c of the mirror body portion 41a of the movable reflecting member (second concave mirror 40) (FIG. 9). The frame body portion 46a has a square-ring-shaped main wall portion 46a that covers the outer peripheral edge portion 40c of the mirror body portion 41a of the movable reflecting member (second concave mirror 40) from the reflecting surface 40a side. １ and a rectangular annular side wall portion 46a that covers the outer peripheral edge portion 40c of the mirror body portion 41a of the movable reflecting member (second concave mirror 40) from the side end side. ２ The bezel member 46 shown here has a side wall portion 46a of a frame portion 46a for each clamped portion 41b of the movable reflecting member (second concave mirror 40). ２The frame portion 46a has a side wall portion 46a of the frame body portion 46a, which projects from the frame portion 46a so as to face the clamped portion 41b, and which clamps the clamped portion 41b of the movable reflecting member (second concave mirror 40) between the clamping portion 45b of the holding member 45 and the clamped portion 41b (FIG. 9). ２ In the vehicle, clamping portions 46b are provided on two wall portions located in the vehicle width direction and one wall portion located above the vehicle.

[0021] The clamping portion 45b of the holding member 45 and the clamping portion 46b of the bezel member 46 are fixed with screws at positions other than the clamping portion that clamps the clamped portion 41b of the movable reflecting member (second concave mirror 40). In this example, both ends with the clamping portion in between are fixed with screws.

[0022] At the clamping location, an elastic member 47 is interposed between the clamped portion 41b of the movable reflecting member (second concave mirror 40) and the clamping portion 46b of the bezel member 46 (FIG. 7). As a result, in this vehicle display device 1, when an external input is transmitted to the holding member 45 or when the output of a motor 51 (described later) is transmitted to the holding member 45, the elastic member 47 absorbs the vibration and reduces the input of the vibration to the movable reflecting member (second concave mirror 40), thereby suppressing distortion and shaking of the virtual image display.

[0023] Here, the vehicle display device 1 includes a drive unit 50 that rotates the movable reflecting member (second concave mirror 40) around a rotation axis to change the imaging position (display position) of the virtual image (see FIGS. 1, 5, and 6). Here, the movable reflecting member (second concave mirror 40) is rotated around a rotation axis in the vehicle width direction to change the imaging position (display position) of the virtual image in the vehicle up-down direction. 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 movable reflecting member (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 being the vehicle width direction (see FIGS. 1 and 6).

[0024] The power transmission mechanism 52 may be a mechanism that directly applies a rotational torque corresponding to the output torque of the motor 51 to the rotary 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 movable reflecting member (second concave mirror 40), thereby rotating the rotary shaft 53 that is located at an eccentric position relative to the input point of the linear force.

[0025] The rotation shaft 53 is provided on the holding member 45 (FIG. 8). Therefore, the drive unit 50 rotates the movable reflecting member (second concave mirror 40) around the rotation shaft 53 of the holding member 45 to change the imaging position (display position) of the virtual image. The holding member 45 shown here is provided with a pair of coaxial rotation shafts 53. Each rotation shaft 53 is formed in a columnar or cylindrical shape and protrudes from two clamping portions 45b located on the holding member 45 in the vehicle width direction.

[0026] 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 receiving portion 52a on the movable reflecting member (second concave mirror 40) side to which the linear force is input ( FIG. 8 ). The input receiving portion 52a is provided on the holding member 45. The drive unit 50 rotates the movable reflecting member (second concave mirror 40) around the axis of the rotation shaft 53 of the holding member 45 by applying a linear force corresponding to the output torque of the motor 51 to the input receiving portion 52a. The holding member 45 shown here has the input receiving portion 52a on the remaining side (the side located below the vehicle) where the clamping portion 45b is not provided. As a result, the input receiving portion 52a is positioned eccentrically with respect to the rotation shaft 53.

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] 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).

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 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.

[0038] 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).

[0039] 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.

[0040] 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.

[0041] 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).

[0042] The first inner case 80A has a first internal space 81a (FIGS. 5, 10, and 11) 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, 10, and 11).

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] The second inner case 80B has a second internal space 82a (FIGS. 5 and 12) 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 12).

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] The second inner case 80B is fixed to the lower case 70A with screws.

[0053] As described above, the vehicle display device 1 of this embodiment holds the movable reflective member (second concave mirror 40) from the rear surface 40b with the holding member 45, and the holding member 45 is provided with the rotation axis 53. Therefore, compared to a device in which a rotation axis is provided on the movable reflective member (second concave mirror 40), this vehicle display device 1 can suppress deformation of the movable reflective member (second concave mirror 40) even if the load on the rotation axis 53 increases due to an increase in mass associated with an increase in the size of the movable reflective member (second concave mirror 40). Therefore, the vehicle display device 1 of this embodiment can suppress distortion and shaking of the virtual image display even if the movable reflective member (second concave mirror 40) is enlarged.

[0054] Furthermore, the holding member 45 is molded from a highly rigid material that is more rigid than the movable reflecting member (second concave mirror 40). Therefore, the vehicle display device 1 can suppress deformation of the holding member 45, and thereby suppress deformation of the movable reflecting member (second concave mirror 40). Therefore, the vehicle display device 1 of this embodiment can suppress distortion and shaking of the virtual image display even if the movable reflecting member (second concave mirror 40) is enlarged.

[0055] Furthermore, in the vehicle display device 1 of this embodiment, the outer peripheral edge 40c of the reflective surface 40a of the movable reflective member (second concave mirror 40) is covered with the bezel member 46. Therefore, even if distortion occurs in the outer peripheral edge 40c of the movable reflective member (second concave mirror 40) during manufacturing, the vehicle display device 1 of this embodiment can hide this distortion, thereby suppressing distortion in the outer peripheral edge of the virtual image display.

[0056] Furthermore, in the vehicle display device 1 of this embodiment, a resin adhesive is interposed between the central portion of the back surface 40b of the movable reflecting member (second concave mirror 40) and the holding member 45. Therefore, in the vehicle display device 1 of this embodiment, when an external input is transmitted to the holding member 45 or when the output of the motor 51 is transmitted to the holding member 45, deformation of the central portion of the movable reflecting member (second concave mirror 40) can be suppressed, and distortion and shaking of the virtual image display can be suppressed.

[0057] Furthermore, in the vehicle display device 1 of this embodiment, an elastic member 47 is interposed between the clamped portion 41b of the movable reflecting member (second concave mirror 40) and the clamping portion 46b of the bezel member 46. Therefore, in the vehicle display device 1 of this embodiment, when an external input is transmitted to the holding member 45 or when the output of the motor 51 is transmitted to the holding member 45, the elastic member 47 absorbs the vibration and reduces the input of the vibration to the movable reflecting member (second concave mirror 40), thereby suppressing distortion and shaking of the virtual image display.

[0058] In this way, the vehicle display device 1 of this embodiment can ensure the display quality of the virtual image.

[0059] Furthermore, 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 increasing 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.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] 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.

[0064] 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.

[0065] DESCRIPTION OF SYMBOLS 1 Vehicle display device 10 Display unit 11 Display 20 Plane mirror (reflecting member) 30 First concave mirror (reflecting member) 40 Second concave mirror (movable reflecting member) 40a Reflecting surface 40b Back surface 40c Outer peripheral edge portion 45 Holding member 46 Bezel member 50 Drive unit 53 Rotating shaft 70 Outer case (housing) 70a Light exit port (opening) 80 Inner case (housing) 80A First inner case 80B Second inner case Rwf Projected portion

Claims

1. A vehicle display device comprising: a housing; a display unit that emits display information into the housing as display light to be viewed as a virtual image by occupants in the vehicle cabin; one reflective member or multiple reflective members that reflect the display light emitted from the display of the display unit within the housing; a holding member that uses the one reflective member or one of the multiple reflective members as a movable reflective member, molded from a high-rigidity material that is more rigid than the movable reflective member, and that holds the movable reflective member from the back side behind the reflecting surface of the display light; a bezel member that covers the outer peripheral edge of the reflective surface of the movable reflective member and sandwiches the movable reflective member between itself and the holding member; and a drive unit that rotates the movable reflective member around the rotation axis of the holding member to change the display position of the virtual image.

2. The vehicle display device according to claim 1, wherein the movable reflecting member has a central portion of the rear surface attached to the holding member with a resin adhesive.

3. A vehicle display device as described in claim 1 or 2, comprising, as the plurality of reflective members, a plane mirror that reflects the display light emitted from the display of the display unit within the housing, a first concave mirror that reflects the display light reflected by the plane mirror within the housing, and a second concave mirror that reflects the display light reflected by the first concave mirror within the housing and projects the display light from an opening in the housing onto a projection target within the vehicle cabin, wherein the second concave mirror is set as the movable reflective member.

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