Image emitting device

Abstract

Attached are positioning members (80) that vertically position first and second shaft parts (44A, 44B) of a second reflecting mirror (40), which are placed on respective placement parts (52h, 52j) of a first housing (52). The positioning members (80) are each configured from a sheet spring that is provided with a base part (82) and a lever part (84). In a state in which the base parts (82) are engaged with the first housing (52), the first and second shaft parts (44A, 44B) are elastically pressed from above at the lever parts (84). Thus, it is possible to perform assembly to the first housing (52) without the need for screw fastening or the like.

Description

Image projection device

[0001] The present disclosure relates to an image projection device configured to project a display image on an image display unit.

[0002] 2. Description of the Related Art There is known an in-vehicle image projection device that is disposed inside a vehicle cabin and projects a display image onto an image display unit such as a front window (i.e., windshield) or a light-transmitting plate disposed inside the vehicle cabin.

[0003] The image projection device of Patent Document 1 includes an image generation unit that generates an image for display, a reflecting mirror that reflects light emitted from the image generation unit toward an image display unit, and a housing that accommodates the reflecting mirror.

[0004] In the image projection device described in Patent Document 1, a reflecting mirror is supported on a housing so as to be rotatable about an axis extending in the left-right direction.

[0005] Furthermore, the image generating unit of the image projection device described in Patent Document 1 includes a liquid crystal panel and an optical unit that irradiates the liquid crystal panel with backlight.

[0006] International Publication No. 2020 / 110580

[0007] In such an image projection device, it is necessary to improve the positional accuracy of the reflecting mirror in order to accurately project a display image onto the image display section.

[0008] To improve the positioning accuracy of the reflector, a shaft extending in the axial direction is formed on the side end of the reflector, and a mounting portion for mounting the shaft is formed on the housing. Furthermore, a positioning member for positioning the shaft of the reflector in the up-down direction is attached to the housing. If the positioning member is fixed to the housing by screws or the like, the assembly work will be time-consuming.

[0009] In such an image projection device, in order to accurately project a display image onto the image display section, it is important to position the liquid crystal panel with high accuracy relative to the optical unit.

[0010] In order to improve the positional accuracy of the liquid crystal panel, the image projection device is provided with a panel support member that supports the liquid crystal panel, and as the panel support member, a pair of support members that are arranged to sandwich the liquid crystal panel from both the front and back sides are screwed and fixed at multiple locations.

[0011] However, in this case, the number of components constituting the panel support member increases, making it difficult to construct the image projection device at low cost.

[0012] Such a problem may also occur in image projection devices other than those mounted on vehicles.

[0013] One of the objects of the present disclosure is to provide an image projection device configured to project light emitted from an image generation unit onto an image display unit via a reflecting mirror, which can improve the positional accuracy of the reflecting mirror while eliminating the need for laborious assembly work of a positioning member.

[0014] Furthermore, one of the objects of the present disclosure is to provide an image projection device configured to project a display image onto an image display unit using light emitted from an image generation unit, which has an inexpensive configuration and can position the liquid crystal panel of the image generation unit with high positional accuracy relative to the optical unit.

[0015] The present disclosure aims to achieve the above object by devising a configuration for the positioning member.

[0016] The image projection device according to the present disclosure is an image projection device configured to project a display image onto an image display section, comprising: an image generation unit that generates the display image; a reflecting mirror that reflects light emitted from the image generation unit towards the image display section; and a housing that accommodates the reflecting mirror; the reflecting mirror is supported rotatably around an axis extending in the left-right direction relative to the housing; a shaft portion extending in the axial direction is formed at a side end of the reflecting mirror; a mounting portion is formed on the housing to mount the shaft portion; a positioning member that positions the shaft portion in the up-down direction is attached to the housing; the positioning member is composed of a leaf spring having a base portion and a lever portion; and the positioning member is configured so that the lever portion elastically presses the shaft portion from above while the base portion is engaged with the housing.

[0017] The image projection device is not particularly limited in its specific use as long as it is configured to project a display image on an image display unit. The image projection device may be, for example, an in-vehicle head-up display.

[0018] The terms indicating the directionality such as the left-right direction and the up-down direction conveniently indicate the directionality of the image projection device itself when the image projection device is placed with the direction in which the axis extends set as the left-right direction. Such directionality is unrelated to the directionality when the image projection device is actually used (for example, the directionality when mounted on a vehicle).

[0019] The image display unit is not particularly limited in its specific configuration as long as it is configured to display an image for display, and may be, for example, a translucent plate disposed on the front windshield of the vehicle or on the interior side of the vehicle.

[0020] The reflecting mirror is not particularly limited in terms of the specific shape of its reflecting surface, as long as it is configured to reflect the light emitted from the image generating unit toward the image display section.

[0021] The positioning member is made of a leaf spring having a base and a lever. The specific configuration of the positioning member is not particularly limited as long as the lever is configured to elastically press the shaft of the reflector from above while the base is engaged with the housing.

[0022] The present disclosure aims to achieve the above object by devising a configuration for the panel support member.

[0023] The image projection device according to the present disclosure is an image projection device configured to project a display image onto an image display section, comprising: an image generation unit that generates the display image; and a reflecting mirror that reflects light emitted from the image generation unit towards the image display section; the image generation unit comprises a liquid crystal panel, an optical unit that irradiates the liquid crystal panel with backlight; and a panel support member that supports the liquid crystal panel; an opening is formed in the panel support member to allow backlight irradiation light from the optical unit to pass towards the reflecting mirror; and a pair of engagement portions that engage with both side edges of the liquid crystal panel are formed in portions of the panel support member located on both sides of the opening; and the liquid crystal panel is supported by the panel support member by sliding the liquid crystal panel relative to the panel support member to engage with the pair of engagement portions.

[0024] The opening is not particularly limited in its specific shape, as long as it is formed so as to allow the backlight emitted from the optical unit to pass through toward the reflecting mirror.

[0025] The panel support member has a pair of engagement portions formed at portions located on both sides of the opening. The specific orientation of the sides of the opening is not particularly limited. The pair of engagement portions may be formed, for example, on both the left and right sides or both the top and bottom sides.

[0026] The pair of engaging portions are not particularly limited in terms of their specific shape or arrangement, as long as they are configured to be able to engage with both side edges when the liquid crystal panel is slid.

[0027] In the image projection device according to the present disclosure, a reflector that reflects light emitted from an image generation unit toward an image display unit is supported rotatably about an axis extending in the left-right direction relative to a housing that accommodates the reflector. A shaft extending in the axial direction is formed at a side end of the reflector. The housing is formed with a mounting portion on which the shaft is placed. A positioning member that positions the shaft in the up-down direction is attached to the housing. Therefore, the present disclosure can improve the positional accuracy of the reflector, thereby enabling the image to be displayed to be accurately projected on the image display unit.

[0028] The positioning member is composed of a leaf spring having a base and a lever. With the base engaged with the housing, the lever resiliently presses the shaft from above. This allows the positioning member to be attached to the housing without the need for screw tightening or other operations, thereby reducing the time and effort required for assembly.

[0029] Thus, according to the present disclosure, in an image projection device configured to project light emitted from an image generation unit onto an image display unit via a reflecting mirror, the positional accuracy of the reflecting mirror can be improved while eliminating the need for laborious assembly work of the positioning member.

[0030] In the above configuration, the base portion of the positioning member includes a horizontal surface portion extending horizontally and a pair of front and rear vertical surface portions extending vertically downward from the front and rear end positions. An opening extending in the front and rear direction is formed in the horizontal surface portion. The lever portion of the positioning member may be formed so as to extend from the front or rear end position of the opening toward the inside of the opening in a downwardly convex curve. In this case, it is easy to elastically press the shaft portion from above. This makes it easy to accurately position the shaft portion of the reflector relative to the housing.

[0031] Note that the terms indicating directionality, such as the horizontal direction and the vertical downward direction, conveniently indicate the directionality when the image projection device is disposed with the direction in which the axis extends set as the left-right direction as described above. These directionality is unrelated to the directionality when the image projection device is actually used. For example, when the image projection device is mounted on a vehicle or the like, the horizontal surface portion may be disposed so as to extend in the horizontal direction or so as to extend in a direction inclined with respect to the horizontal direction.

[0032] Furthermore, a second lever portion extending downward may be formed at a midpoint in the front-rear direction on the horizontal surface portion. The second lever portion may abut against a tip end surface of the shaft portion of the reflector and elastically press the tip end surface in the axial direction. In this case, it is easy to position the shaft portion of the reflector relative to the housing not only in the up-down direction but also in the axial direction.

[0033] The base portion of the positioning member may have a pair of front and rear vertical surfaces each having a second opening, and a locking piece extending from a lower end thereof into the second opening. The pair of front and rear locking pieces may extend at an angle away from each other in the vertical direction and be locked to the housing by the locking piece. This configuration can further improve the positioning accuracy of the reflecting mirror.

[0034] The housing may have insertion holes formed on both front and rear sides of the mounting portion, through which the pair of front and rear vertical surfaces are inserted. The housing may have locking portions formed near the pair of front and rear insertion holes, respectively, that lock the positioning member by abutting the upper edges of the pair of front and rear locking pieces. This configuration ensures that the positioning member is securely locked to the housing.

[0035] The image projection device according to the present disclosure reflects light emitted from an image generation unit toward an image display unit using a reflecting mirror. The image generation unit includes a liquid crystal panel, an optical unit that illuminates the liquid crystal panel with backlight, and a panel support member that supports the liquid crystal panel. The panel support member has an opening that allows the backlight emitted from the optical unit to pass through toward the reflecting mirror. This makes it easy for the backlight emitted from the optical unit to reach the reflecting mirror via the liquid crystal panel.

[0036] A pair of engagement portions that engage with the edge portions of the liquid crystal panel are formed in the panel support member at portions located on both sides of the opening. The liquid crystal panel is supported by the panel support member by sliding the liquid crystal panel relative to the panel support member to engage with the pair of engagement portions, which provides the following advantageous effects.

[0037] That is, compared to a configuration in which a pair of support members are arranged on both the front and rear sides of the liquid crystal panel and are fastened with screws at multiple locations in order to position the liquid crystal panel with high positional accuracy relative to the optical unit, the configuration of the panel support members can be simplified, which allows the image projection device to be constructed inexpensively.

[0038] Thus, according to the present disclosure, in an image projection device configured to project a display image onto an image display unit using light emitted from an image generation unit, the liquid crystal panel of the image generation unit can be positioned with high positional accuracy relative to the optical unit using an inexpensive configuration.

[0039] Furthermore, as a configuration of each of the pair of engaging portions, a front contact portion that contacts the front surface of the liquid crystal panel and a rear contact portion that contacts the rear surface of the liquid crystal panel may be formed alternately at different positions with respect to the sliding direction of the liquid crystal panel. In this case, molding of the panel support member is easy, and it becomes possible to efficiently clamp the liquid crystal panel from both the front and rear sides.

[0040] If each of the pair of engaging portions is configured so that front contact portions and rear contact portions are formed at a plurality of locations in the sliding direction, the following effects can be obtained.

[0041] In other words, when both side edges of the liquid crystal panel are engaged with the pair of engagement portions, the liquid crystal panel receives a pressing force from the front side of the device due to contact with the front contact portion, and receives a pressing force from the rear side of the device due to contact with the rear contact portion, which may cause bending deformation of the liquid crystal panel due to the application of opposite pressing forces at different positions in the sliding direction.

[0042] In contrast, by forming the front contact portion and the rear contact portion at multiple locations in the sliding direction as the configuration of each of the pair of engagement portions, the pressing forces from the front side of the device and the pressing forces from the rear side of the device can be dispersed and reduced to multiple locations in the sliding direction, thereby minimizing the risk of bending deformation of the liquid crystal panel supported by the panel support member.

[0043] In the above configuration, the panel support member may further include a positioning portion formed at a portion located forward of the opening in the sliding direction, the positioning portion abutting against the front edge of the liquid crystal panel in the sliding direction to position the liquid crystal panel in the sliding direction. In this case, the positioning accuracy of the liquid crystal panel can be improved.

[0044] Furthermore, the panel support member may be provided with a holding structure at a location located rearward of the opening in the sliding direction, which holds the liquid crystal panel in a position relative to the sliding direction by engaging with the rear edge of the liquid crystal panel in the sliding direction. In this case, the liquid crystal panel can be maintained in a stable position relative to the panel support member.

[0045] FIG. 1 is a side cross-sectional view showing an image projection device according to a first embodiment of the present disclosure mounted on a vehicle. FIG. 2 is a view seen from the direction of arrow II in FIG. 1. FIG. 3 is a detailed view of portion III in FIG. 1. FIG. 4 is a plan view showing the image projection device with the second housing removed. FIG. 5 is a cross-sectional view taken along line V-V in FIG. 4. FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 5. FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. 6. FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 6. FIG. 9 is a perspective view showing a positioning member of the image projection device alone. FIG. 10 is a cross-sectional view taken along line V-V in FIG. 4, in a modified example of the first embodiment. FIG. 11 is a side cross-sectional view showing an image projection device according to a second embodiment of the present disclosure mounted on a vehicle. FIG. 12 is a detailed view of portion XII in FIG. 11. FIG. 13 is a cross-sectional view taken along line XIII-XIII in FIG. 12. FIG. 14 is a front view showing how a liquid crystal panel is assembled to a panel support member of the image projection device. Fig. 15A is a cross-sectional view taken along line XV-XV in Fig. 14, showing the assembling process. Fig. 15B ...C is a perspective view showing the assembling process. Fig. 15D is a perspective view showing the assembling process in a first modified example of the second embodiment. Fig. 15E is a front view showing the assembling process of the liquid crystal panel to the panel support member in a second modified example of the second embodiment. Modes for carrying out the invention

[0046] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0047] Fig. 1 is a side cross-sectional view showing an image projection device 10 according to a first embodiment of the present disclosure in a state where it is mounted on a vehicle 100. Fig. 2 is a view taken in the direction of an arrow II in Fig. 1 .

[0048] 1 and 2, the direction indicated by X is the "forward" direction of the image projection device 10 (also "forward" as a vehicle). The direction indicated by Y is the "leftward direction" perpendicular to the "forward" direction. The direction indicated by Z is the "upward direction." This is also true for figures other than FIG. 1 and FIG. 2.

[0049] 1 and 2, the image projection device 10 according to this embodiment is an in-vehicle head-up display. The image projection device 10 is configured to project a display image PIC as a virtual image on an image display unit 102A set on the inner surface of a front windshield 102 when placed in the cabin of a vehicle 100.

[0050] An optical path R shown in FIG. 1 is an optical path taken by the driver 2 when visually perceiving the display image PIC projected on the image display unit 102A by the image projection device 10.

[0051] The image display unit 102A is located in the lower region of the windshield 102 and in the region in front of the steering wheel 104, and has a horizontally long rectangular region, so that the driver 2 of the vehicle 100 can easily visually recognize the display image PIC displayed on the image display unit 102A.

[0052] FIG. 2 shows a specific example of the display image PIC in which the vehicle speed (50 km / h) is displayed together with a left-pointing arrow.

[0053] The image projection device 10 is disposed in front of the steering wheel 104 and in the vicinity of the lower part of the windshield 102 .

[0054] As shown in Fig. 1, the image projection device 10 includes an image generation unit 20, first and second reflecting mirrors 30 and 40, a housing 50, and a light-transmitting cover 60. The image generation unit 20 generates a display image that is the basis of the display image PIC. The first and second reflecting mirrors 30 and 40 sequentially reflect light emitted from the image generation unit 20 toward an image display section 102A on a windshield 102. The housing 50 accommodates the first and second reflecting mirrors 30 and 40. The light-transmitting cover 60 is attached to the housing 50.

[0055] The image generating unit 20 and the first and second reflectors 30, 40 are supported in a housing 50 (which will be described below).

[0056] The housing 50 includes a first housing 52 and a second housing 54. The second housing 54 is assembled to the first housing 52, which is formed to open upward.

[0057] Fig. 3 is a detailed view of part III in Fig. 1. Fig. 4 is a plan view showing the image projection device 10 in a state where the second housing 54 has been removed. Fig. 5 is a cross-sectional view taken along line VV in Fig. 4.

[0058] 3 to 5, the second housing 54 has an outer peripheral flange 54b. The second housing 54 is attached to the first housing 52 with the outer peripheral flange 54b abutting against the upper end opening 52a of the first housing 52.

[0059] The first and second housings 52, 54 are both made of opaque resin moldings. The second housing 54 has an opening 54a formed therein that allows reflected light from the second reflecting mirror 40 to pass through toward the image display unit 102A.

[0060] The light-transmitting cover 60 is made of a colorless, transparent resin panel. The light-transmitting cover 60 is arranged in a state where it is curved downward and tilted slightly upward toward the rear so as to cover the opening 54a of the second housing 54. The light-transmitting cover 60 is configured to ensure dustproofness of the internal space 12 of the housing 50 while allowing reflected light from the second reflecting mirror 40 to enter the image display unit 102A.

[0061] 4 and 5, the reflecting surface 30a of the first reflecting mirror 30 has a bilaterally symmetrical shape. The reflecting surface 40a of the second reflecting mirror 40 has a bilaterally symmetrical shape. The image generating unit 20 is disposed at the center position of the reflecting surfaces 30a, 40a in the left-right direction.

[0062] The image generating unit 20 includes a liquid crystal panel 22 having a rectangular outer shape. The liquid crystal panel 22 is disposed so as to face the interior space 12 of the housing 50. Specifically, the image generating unit 20 is supported by the lower wall portion 52b of the first housing 52 with the longitudinal direction of the liquid crystal panel 22 extending in the left-right direction (i.e., the vehicle width direction) and with the liquid crystal panel 22 facing diagonally upward and rearward.

[0063] The image generation unit 20 is configured to generate a display image (i.e., an image that serves as the basis for the display image PIC) on the liquid crystal panel 22 by illuminating the liquid crystal panel 22 with backlight from the rear side of the liquid crystal panel 22.

[0064] A unit mounting portion 52d for mounting the image generating unit 20 is formed on the lower wall portion 52b of the first housing 52. A rectangular opening 52e that is slightly larger than the outer shape of the liquid crystal panel 22 is formed in the unit mounting portion 52d.

[0065] The image generating unit 20 is fixed to the lower wall portion 52b of the first housing 52 by screwing or the like, with the liquid crystal panel 22 positioned so as to fit into the opening 52e of the unit mounting portion 52d.

[0066] The first reflecting mirror 30 is disposed diagonally above and behind the image generating unit 20 and is configured to reflect the light emitted from the image generating unit 20 forward.

[0067] The surface shape of the reflective surface 30a of the first reflecting mirror 30 is a saddle-shaped curved surface, and the first reflecting mirror 30 is a saddle-shaped reflecting mirror. The reflective surface 30a of the first reflecting mirror 30 has a substantially rectangular outer shape extending in the left-right direction when viewed from the front of the vehicle. Specifically, the horizontal cross-sectional shape of the reflective surface 30a is a convex curve, and the vertical cross-sectional shape of the reflective surface 30a is a concave curve.

[0068] Flanges 32 are formed on both left and right end portions of the reflecting surface 30a of the first reflecting mirror 30. The first reflecting mirror 30 is fixed to the first housing 52 at the pair of left and right flanges 32.

[0069] Specifically, each flange 32 includes a side wall 32A formed to extend rearward along a vertical plane from the side end of the reflecting surface 30a, and a stepped portion 32B formed to extend laterally from the outer surface of the side wall 32A. The first reflecting mirror 30 is fastened to a pair of left and right columnar protrusions 52f formed on the bottom wall 52b of the first housing 52 by screws 34, with the pair of left and right stepped portions 32B being fastened in position by pins 52g.

[0070] 3 and 4, the second reflecting mirror 40 is disposed in front of the first reflecting mirror 30. The second reflecting mirror 40 is configured to reflect the irradiation light from the image generating unit 20, which is reflected by the first reflecting mirror 30, upward.

[0071] The second reflecting mirror 40 is a concave mirror. The surface shape of the reflecting surface 40a of the second reflecting mirror 40 is configured as a substantially spherical concave curved surface. The reflecting surface 40a of the second reflecting mirror 40 has a rectangular outer shape extending in the left-right direction when viewed from the front of the vehicle. The reflecting surface 40a of the second reflecting mirror 40 is formed to be larger in size than the reflecting surface 30a of the first reflecting mirror 30, and is formed to have a larger aspect ratio (i.e., a more horizontally elongated shape) than the reflecting surface 30a of the first reflecting mirror 30.

[0072] In this way, the reflective surface 40a of the second reflecting mirror 40 is formed with a larger aspect ratio than the reflective surface 30a of the first reflecting mirror 30, while being significantly curved in the direction of the image desired to be viewed by the driver 2. Because the first reflecting mirror 30 is configured as a saddle-shaped reflecting mirror, the reflected light from the reflective surface 30a of the first reflecting mirror 30 has a small spread in the vertical direction and a large spread in the horizontal direction, and is efficiently incident on the reflective surface 40a of the second reflecting mirror 40.

[0073] The lower wall portion 52b of the first housing 52 is formed at a higher position than the portion where the unit mounting portion 52d is formed and the portion located below the reflective surfaces 30a, 40a of the first and second reflectors 30, 40, and the portion located around that portion.

[0074] 3, the second housing 54 is formed with a light-shielding piece 54c that covers the peripheral area of ​​the reflecting surface 30a of the first reflecting mirror 30. The light-shielding piece 54c is formed in a plate shape that extends obliquely downward and forward from the rear edge of the opening 54a of the second housing 54 toward the internal space 12.

[0075] In the image projection device 10, sunlight S entering the vehicle interior through the front window 102 may enter the internal space 12 of the housing 50 through the light-transmitting cover 60. However, the light-shielding piece 54c prevents the sunlight S from reaching the peripheral area of ​​the reflecting surface 30a of the first reflecting mirror 30.

[0076] Furthermore, when performing surface treatment to form the reflecting surface 30a of the first reflecting mirror 30, a vapor deposition film or the like may adhere to the peripheral region of the reflecting surface 30a. The light-shielding piece 54c prevents sunlight S that reaches the peripheral region from being reflected by the vapor deposition film or the like and becoming stray light.

[0077] 4 and 5 , the second reflecting mirror 40 is supported by the first housing 52 so as to be rotatable about an axis Ax extending in the left-right direction near the front of the second reflecting mirror 40. The second reflecting mirror 40 is configured to perform angle adjustment so that the reflected light from the first reflecting mirror 30 is accurately incident on the image display unit 102A of the front windshield 102.

[0078] A pair of left and right vertical flanges 42 extending forward along a vertical plane are formed on both left and right end portions on the rear side of the reflecting surface 40a of the second reflecting mirror 40. First and second shafts 44A, 44B extending in both left and right directions (i.e., directions away from the reflecting surface 40a) on the axis Ax are formed on the pair of left and right vertical flanges 42.

[0079] The first and second shaft portions 44A, 44B are both cylindrical. A portion of the second shaft portion 44B located on the right side (left side when viewed from the front of the device) has a smaller outer diameter than the first shaft portion 44A located on the left side. The tip of the second shaft portion 44B has the same outer diameter as the first shaft portion 44A.

[0080] A base end 46a of an arm member 46 extending toward the rear of the device is fixed to the tip surface of the second shaft portion 44B. The base end 46a of the arm member 46 is formed to extend in a cylindrical shape coaxially with the second shaft portion 44B. The outer diameter of the base end 46a is the same as the outer diameter of the tip of the second shaft portion 44B.

[0081] The tip 46b of the arm member 46 is connected to a direct acting output shaft 72a of an actuator 70A that rotates the second reflecting mirror 40 about the axis Ax.

[0082] The actuator 70A is fixed to the lower wall portion 52b on the lower side of the first housing 52. The direct acting output shaft 72a is formed to extend upward into the internal space 12 of the housing 50.

[0083] A pair of left and right mounting portions 52h, 52j are formed in a portion located directly below the axis Ax on the lower wall portion 52b of the first housing 52. The first shaft portion 44A of the second reflecting mirror 40 is mounted on the mounting portion 52h, and the base end portion 46a of the arm member 46 fixed to the second shaft portion 44B is mounted on the mounting portion 52j.

[0084] The pair of left and right mounting portions 52h, 52j are formed so as to extend in the direction of the axis Ax from the inner surface of the peripheral wall portion 52c of the first housing 52 in the shape of a semi-cylindrical surface with an inner diameter substantially equal to the outer diameter of the first shaft portion 44A and the base end portion 46a of the arm member 46. The upper ends of the pair of left and right mounting portions 52h, 52j are formed so as to have a substantially V-shaped slope in a side view (see FIG. 6).

[0085] The first shaft portion 44A and the base end portion 46a of the arm member 46 are positioned in the vertical direction by a pair of left and right positioning members 80 attached to the first housing 52 while placed on a pair of left and right mounting portions 52h, 52j.

[0086] The pair of left and right positioning members 80 are each made of a leaf spring having the same shape. Therefore, the specific configuration of the positioning member 80 disposed on the right-side mounting portion 52j will be described below.

[0087] Fig. 6 is a cross-sectional view taken along line VI-VI in Fig. 5. Fig. 7 is a cross-sectional view taken along line VII-VII in Fig. 6. Fig. 8 is a cross-sectional view taken along line VIII-VIII in Fig. 6. Fig. 9 is a perspective view showing the positioning member 80 alone.

[0088] 6 to 9, the positioning member 80 is made up of a leaf spring including a base portion 82 and a lever portion 84. The positioning member 80 is configured so that the lever portion 84 elastically presses the base end portion 46a of the arm member 46 from above while the base portion 82 is engaged with the first housing 52.

[0089] The base portion 82 includes a horizontal surface portion 82A extending horizontally, and a pair of front and rear vertical surface portions 82B extending vertically downward from the front and rear end positions of the horizontal surface portion 82A.

[0090] An opening 82Aa extending in the front-rear direction is formed in the horizontal surface portion 82A. The opening 82Aa has a generally rectangular opening shape extending in the front-rear direction in a plan view.

[0091] The lever portion 84 is formed to extend from the rear end position of the opening 82Aa toward inside the opening 82Aa. The lever portion 84 has a rectangular outer shape extending in the front-to-rear direction in a plan view. The lever portion 84 is formed to extend toward inside the opening 82Aa in a downward convex curve.

[0092] A second lever portion 86 extending downward is formed on the right side surface of the horizontal surface portion 82A at a central position in the front-to-rear direction. The second lever portion 86 protrudes rightward from the right edge of the horizontal surface portion 82A and is curved concavely leftward, thereby forming a generally M-shape facing sideways when viewed from the front of the device. As shown in FIG. 7 , the second lever portion 86 is configured to abut against the tip surface 46a1 of the base end portion 46a of the arm member 46, thereby elastically pressing the base end portion 46a leftward (i.e., elastically pressing the second reflecting mirror 40 in the direction of the axis Ax).

[0093] A vertically elongated, generally rectangular second opening 82Ba is formed in each of the pair of front and rear vertical surface portions 82B. A vertically elongated, rectangular locking piece 88 is formed in each of the pair of front and rear vertical surface portions 82B and extends from the lower end of the second opening 82Ba toward the inside of the second opening 82Ba.

[0094] The pair of front and rear locking pieces 88 are formed to extend at an angle away from each other in the vertically upward direction. The positioning member 80 is locked to the first housing 52 by the pair of front and rear locking pieces 88. The specific locking structure is as follows.

[0095] That is, the first housing 52 has upper planar portions 52k located on both front and rear sides of the mounting portion 52j on the lower wall portion 52b, which extend along a horizontal plane above the axis Ax. The upper surface of the upper planar portion 52k is formed to be at approximately the same height as the upper end position of the outer circumferential surface of the base end portion 46a of the arm member 46 mounted on the mounting portion 52j. A pair of front and rear insertion holes 52m, through which the pair of front and rear vertical surface portions 82B are inserted, are formed in the upper planar portion 52k on both front and rear sides of the mounting portion 52j. Furthermore, the lower surface of the upper planar portion 52k near the pair of front and rear insertion holes 52m is formed as a pair of front and rear locking portions 52n that lock the positioning member 80 by abutting the upper edges of the pair of front and rear locking pieces 88.

[0096] The first housing 52 is formed with a pair of front and rear vertical ribs 52p extending downward from the upper flat surface 52k on both the front and rear of the pair of front and rear locking portions 52n. These pair of front and rear vertical ribs 52p are integrally formed with the peripheral wall portion 52c of the first housing 52 on the right side of the mounting portion 52j. Such a pair of front and rear vertical ribs 52p ensures sufficient rigidity of the first housing 52 around the mounting portion 52j.

[0097] As shown in Figures 4 and 5, the positioning structure for the first shaft portion 44A placed on the left-side mounting portion 52h has a configuration that is approximately the same as the positioning structure for the base end portion 46a of the arm member 46 placed on the right-side mounting portion 52j.

[0098] That is, the first housing 52 has upper flat portions 52k that extend along the horizontal plane above the axis Ax at portions of the lower wall 52b of the first housing 52 located on both the front and rear sides of the mounting portion 52h. A pair of front and rear insertion holes 52m are formed in the front and rear portions of the mounting portion 52j.

[0099] The first shaft 44A placed on the left-side mounting portion 52h is positioned relative to the first housing 52 by a positioning member 80. The positioning member 80 placed on the left-side mounting portion 52h is arranged in a state where the positioning member 80 placed on the right-side mounting portion 52j is oriented in the reverse direction.

[0100] In this way, the positioning member 80 abuts the second lever portion 86 against the tip surface of the first shaft portion 44A placed on the mounting portion 52h, thereby elastically pressing the first shaft portion 44A in the right direction.

[0101] Next, the operation of this embodiment will be described.

[0102] In the image projection device 10 according to this embodiment, the second reflecting mirror 40, which reflects light emitted from the image generation unit 20 toward the image display unit 102A, is supported rotatably about an axis Ax extending in the left-right direction relative to a first housing 52 of a housing 50 that accommodates the second reflecting mirror 40. First and second shafts 44A, 44B extending in the direction of the axis Ax are formed at the side ends of the second reflecting mirror 40. The first housing 52 is formed with mounting portions 52h, 52j on which the first and second shafts 44A, 44B (more precisely, the first shaft 44A and the base end 46a of the arm member 46) are mounted. A positioning member 80 is attached to the first housing 52 to position the first and second shafts 44A, 44B in the up-down direction. This improves the positional accuracy of the second reflecting mirror 40, thereby enabling the display image PIC to be accurately displayed on the image display unit 102A.

[0103] The positioning member 80 is made up of a leaf spring including a base portion 82 and a lever portion 84. The positioning member 80 is configured so that the lever portion 84 elastically presses the first and second shaft portions 44A, 44B from above while the base portion 82 is engaged with the first housing 52. This allows the positioning member 80 to be assembled to the first housing 52 without the need for screw tightening or other operations, thereby reducing the labor required for the assembly work.

[0104] As described above, according to this embodiment, in the image projection device 10, the positioning accuracy of the second reflecting mirror 40 can be improved while reducing the time and effort required for assembling the positioning member 80.

[0105] In the positioning member 80 of this embodiment, the base portion 82 includes a horizontal surface portion 82A extending horizontally and a pair of front and rear vertical surface portions 82B. An opening 82Aa extending in the front-to-rear direction is formed in the horizontal surface portion 82A. The lever portion 84 is formed to extend from the front or rear end of the opening 82Aa toward the inside of the opening 82Aa in a downwardly convex curve. This allows the positioning member 80 to easily elastically press the first and second shaft portions 44A, 44B from above. This makes it easy to accurately position the first and second shaft portions 44A, 44B of the second reflecting mirror 40 relative to the first housing 52.

[0106] In this embodiment, the positioning member 80 is formed with a second lever portion 86 extending downward at a central position in the front-to-rear direction on the horizontal surface portion 82A. The second lever portion 86 is configured to abut against the tip surfaces of the first and second shaft portions 44A, 44B of the second reflecting mirror 40 and elastically press them in the direction of the axis Ax. Therefore, the positioning member 80 can easily position the first and second shaft portions 44A, 44B of the second reflecting mirror 40 relative to the first housing 52 not only in the up-and-down direction but also in the direction of the axis Ax.

[0107] The base portion 82 of the positioning member 80 has a pair of front and rear vertical surface portions 82B each having a second opening 82Ba formed therein, and a locking piece 88 extending from the lower end of the second opening 82Ba toward the inside of the second opening 82Ba. The pair of front and rear locking pieces 88 are locked to the first housing 52 in a state in which they extend at an angle away from each other in the vertically upward direction. This further improves the positional accuracy of the second reflecting mirror 40.

[0108] Insertion holes 52m, through which the pair of front and rear vertical surface portions 82B are inserted, are formed in the front and rear sides of the mounting portions 52h, 52j of the first housing 52. Locking portions 52n, which lock the positioning member 80 by abutting the upper edges of the pair of front and rear locking pieces 88, are formed in the first housing 52 near the pair of front and rear insertion holes 52m. This ensures that the positioning member 80 is securely locked to the first housing 52.

[0109] In the above embodiment, the second shaft portion 44B of the second reflector 40 is placed on the mounting portion 52j of the first housing 52 at the base end 46a of the arm member 46 fixed to the second shaft portion 44B, but the second shaft portion 44B itself may be placed on the mounting portion 52j of the first housing 52.

[0110] In the above embodiment, the image projection device 10 may include a single reflector (specifically, only the second reflector 40) instead of the first and second reflectors 30 and 40. Even in such a configuration, it is possible to obtain substantially the same effects as in the above embodiment.

[0111] In the above embodiment, the image display unit 102A is set on the inner surface of the windshield 102, but the image display unit may be formed of a translucent plate or the like arranged on the inner side of the windshield 102 inside the passenger compartment.

[0112] In the above embodiment, the image projection device 10 is an in-vehicle head-up display, but it may also be used for other purposes.

[0113] Next, a modification of the first embodiment will be described.

[0114] FIG. 10 is a cross-sectional view of the image projection device 110 according to this modified example taken along line VV in FIG.

[0115] As shown in FIG. 10, the basic configuration of this modified example is the same as that of the above embodiment, but the support structure of the second reflecting mirror 40 relative to the first housing 52 is partially different from that of the above embodiment.

[0116] That is, this modified example differs from the above embodiment in that the second housing 154 of the housing 150 has the function of positioning the first shaft portion 44A of the second reflecting mirror 40 in the up-down direction.

[0117] Specifically, a downward positioning rib 154d formed on the outer peripheral flange portion 154b of the second housing 154 abuts against the first shaft portion 44A placed on the placement portion 52h of the first housing 52. In this way, the second housing 154 is configured to position the first shaft portion 44A in the up-down direction.

[0118] In this modified example, the second shaft portion 44B (more precisely, the base end portion 46a of the arm member 46) placed on the mounting portion 52j of the first housing 52 is positioned in the vertical direction by a positioning member 80 attached to the first housing 52, as in the above embodiment.

[0119] Even when the configuration of this modified example is adopted, substantially the same effects as those in the above embodiment can be obtained.

[0120] Furthermore, by adopting the configuration of this modified example, the positioning rib 154d comes into contact with the first shaft portion 44A when the second housing 154 is assembled to the first housing 52. This allows the first shaft portion 44A to be positioned.

[0121] On the other hand, when the configuration of this modified example is adopted, the positioning accuracy may be reduced compared to the configuration in which the positioning of the first shaft portion 44A is performed using the elastic pressing force of the positioning member 80 as in the above embodiment. However, even in this modified example, the positioning of the second reflecting mirror 40 relative to the base end portion 46a of the arm member 46 that rotates the second reflecting mirror 40 is performed with high accuracy by the positioning member 80. Therefore, it is possible to maintain the positioning accuracy of the second reflecting mirror 40 within a practically acceptable range.

[0122] Second Embodiment Fig. 11 is a side cross-sectional view showing an image projection device 10X according to a second embodiment of the present disclosure in a state where it is mounted on a vehicle 100. In the configuration shown in Fig. 11, the same components as those shown in Fig. 1 are denoted by the same reference numerals, and the description thereof will be omitted.

[0123] 1 , the image projection device 10X includes an image generation unit 20, a reflecting mirror 40X, a housing 50, and a light-transmitting cover 60. The reflecting mirror 40X reflects light emitted from the image generation unit 20 toward an image display portion 102A of the front windshield 102.

[0124] Fig. 12 is a detailed view of part XII in Fig. 11. Fig. 13 is a cross-sectional view taken along line XIII-XIII in Fig. 12.

[0125] As shown in FIG. 12, the second housing 54 is assembled to the first housing 52 with the outer peripheral flange portion 54b abutting against the upper end surface of the peripheral wall portion 52aX of the first housing 52.

[0126] The image generating unit 20 is disposed in the rear region of the interior space 12. The reflecting mirror 40X is disposed in the front region of the interior space 12.

[0127] The reflecting mirror 40X is a concave mirror. The reflecting surface 40a of the reflecting mirror 40X has a horizontally elongated rectangular outer shape when viewed from the front of the device. The image generating unit 20 is disposed so as to be positioned at the center of the reflecting mirror 40X in the left-right direction.

[0128] The image generation unit 20 includes a liquid crystal panel 22 and an optical unit 30X. The optical unit 30X is configured to illuminate the liquid crystal panel 22 with backlight from the rear side of the liquid crystal panel 22 (i.e., the rear side of the device). The image generation unit 20 is configured to generate a display image (i.e., an image that serves as the basis for the display image PIC) on the liquid crystal panel 22 using backlight illumination from the optical unit 30X.

[0129] The optical unit 30X includes a light-emitting element 32X as a light source, a substrate 34X, a lens 36, and a lens holder 38. The substrate 34X mounts the light-emitting element 32X. The lens 36 deflects and controls the light emitted from the light-emitting element 32X. The lens holder 38 supports the lens 36.

[0130] The lens 36 has a vertical cross-sectional shape of a biconvex lens and a horizontal cross-sectional shape of a plano-convex lens, so that the backlight emitted from the optical unit 30X is efficiently incident on the reflecting surface 40a of the reflecting mirror 40X via the liquid crystal panel 22. The lens 36 is supported by a lens holder 38 at its outer peripheral flange portion 36a.

[0131] The substrate 34X is supported on the heat sink 24 at the rear surface thereof, with the substrate 34X arranged along a vertical plane perpendicular to the front-rear direction of the device so that the light emitting surface of the light emitting element 32X faces the front direction of the device.

[0132] The heat sink 24 includes a main body 24A and multiple heat dissipation fins 24B. The main body 24A extends flat along a vertical plane perpendicular to the front-to-rear direction of the device. The multiple heat dissipation fins 24B extend from the main body 24A toward the rear of the device at intervals in the left-to-right direction. The heat sink 24 is supported by a lens holder 38 at the main body 24A.

[0133] The liquid crystal panel 22 has a horizontally elongated rectangular outer shape and is supported by a panel support member 70 in a state inclined forward with respect to a vertical plane perpendicular to the front-to-rear direction of the device (the specific support structure will be described later).

[0134] The panel support member 70 is disposed so as to cover the optical unit 30X from the front side of the device. The panel support member 70 has an opening 70a formed therein, which allows backlight emitted from the optical unit 30X to pass through toward the reflecting mirror 40X. The opening 70a has a horizontally elongated rectangular opening shape.

[0135] As shown in FIG. 13, the image generating unit 20 is supported by the first housing 52 by fastening the optical unit 30X and the panel support member 70 to the first housing 52 at both left and right ends thereof with screws.

[0136] Specifically, tab-shaped mounting portions 38a are formed on both left and right sides of the lens holder 38, extending along vertical planes perpendicular to the front-to-rear direction of the device. Tab-shaped mounting portions 70b are also formed on both left and right sides of the panel support member 70, extending along vertical planes perpendicular to the front-to-rear direction of the device. Bosses 70c are formed on the mounting portions 70b. With the pair of left and right mounting portions 38a, 70b of the lens holder 38 and panel support member 70 overlapping, they are abutted against the peripheral wall portion 52aX of the first housing 52 from the front side of the device. Furthermore, in this state, screws 46X are fastened from the rear side of the device to the bosses 70c of the panel support member 70 via the mounting portions 38a of the lens holder 38.

[0137] As shown in FIG. 13, the reflecting mirror 40X is supported so as to be rotatable about an axis Ax extending in the left-right direction relative to the first housing 52.

[0138] An actuator 42X that rotates the reflecting mirror 40X about the axis Ax is fixed to the first housing 52. The actuator 42X is fixed by fastening screws 44 to a bottom wall portion 52b of the first housing 52 at tab-shaped mounting portions 42b formed at two locations on the actuator 42X.

[0139] The reflecting mirror 40X includes vertical flanges 40b formed to protrude rearward from both left and right sides of the rear surface (i.e., the surface facing the front of the device) of the reflecting surface 40a of the reflecting mirror 40X. A pair of left and right shafts 40c, 40d are formed on the pair of left and right vertical flanges 40b, protruding outward in the left-right direction along the axis Ax. The left-side shaft 40c (the right-side when viewed from the front of the device) is placed on a mounting portion 52cX formed on the inner surface of a peripheral wall portion 52aX of the first housing 52. The right-side shaft 40d is directly connected to the output shaft 42a of the actuator 42X.

[0140] The mounting portion 52cX has a mounting surface that is substantially U-shaped. The second housing 54 is formed with a contact portion (not shown) that contacts the shaft portion 40c mounted on the mounting portion 52cX from above to position the reflecting mirror 40X.

[0141] Next, a specific support structure for the liquid crystal panel 22 by the panel support member 70 will be described.

[0142] Fig. 14 is a front view showing how the liquid crystal panel 22 is assembled to the panel support member 70. Figs. 15A and 15B are cross-sectional views taken along line XV-XV in Fig. 14, showing the assembly process. Fig. 16 is a perspective view showing the assembly process.

[0143] 14 to 16 , a pair of engagement portions 72 that engage with both side edges of the liquid crystal panel 22 are formed in portions located on both the left and right sides of the opening 70a of the panel support member 70. The liquid crystal panel 22 is supported by the panel support member 70 by sliding the liquid crystal panel 22 from below relative to the panel support member 70 to engage with the pair of left and right engagement portions 72.

[0144] Each of the pair of left and right engagement portions 72 includes a front contact portion 72A and a rear contact portion 72B. The front contact portion 72A contacts the front surface of the liquid crystal panel 22. The rear contact portion 72B is formed alternately at different positions in the sliding direction of the liquid crystal panel 22 (i.e., positions that do not overlap each other when viewed from the front of the device), with the front contact portion 72A contacting the rear surface of the liquid crystal panel 22 and the rear contact portion 72B being formed alternately at different positions in the sliding direction of the liquid crystal panel 22 (i.e., positions that do not overlap each other when viewed from the front of the device).

[0145] Specifically, the front contact portion 72A is formed at the center of the opening 70a in the up-down direction. The rear contact portions 72B are formed at both the top and bottom ends of the opening 70a. The distance between the front contact portion 72A and the pair of upper and lower rear contact portions 72B in the front-to-rear direction of the device is slightly larger than the thickness of the liquid crystal panel 22. The amount by which the front contact portion 72A protrudes toward the opening 70a is slightly smaller than the amount by which the pair of upper and lower rear contact portions 72B protrude toward the opening 70a (although a configuration other than this setting is also possible).

[0146] The panel support member 70 is formed with a positioning portion 74 at a location located forward (i.e., above) the opening 70a in the sliding direction, the positioning portion 74 abutting against the sliding direction front edge of the liquid crystal panel 22. Specifically, the positioning portion 74 is formed to extend horizontally as the upper end surface of the opening 70a.

[0147] The panel support member 70 is provided with a holding structure 76 at a position located rearward (i.e., downward) from the opening 70a in the sliding direction, which holds the liquid crystal panel 22 in a position relative to the sliding direction by engaging with the rear edge of the liquid crystal panel 22 in the sliding direction.

[0148] The holding structure 76 has a pair of left and right locking pieces 76A extending in an L-shape from a pair of left and right rear abutment portions 72B formed at the lower end positions of the opening 70a.

[0149] The pair of left and right locking pieces 76A are formed so as to extend toward each other from the pair of left and right rear abutment portions 72B toward the opening 70a and then extend rearward in the sliding direction. The pair of left and right locking pieces 76A are formed in a flat plate shape with a thickness thinner than the pair of left and right rear abutment portions 72B. However, the front surface of the tip portion 76Aa of each locking piece 76A is formed in a convex shape.

[0150] 15A, when the liquid crystal panel 22 is slid upward relative to the panel support member 70, the pair of left and right locking pieces 76A are configured to bend and deform with their tip ends 76Aa in contact with the rear surface of the liquid crystal panel 22. Furthermore, as shown in Fig. 15B, when the liquid crystal panel 22 is slid to a position where it abuts against the positioning portion 74 of the panel support member 70, the tip ends 76Aa of the pair of left and right locking pieces 76A are configured to engage with the rear edge of the liquid crystal panel 22 in the sliding direction.

[0151] The panel support member 70 has a lower edge 70d located below the opening 70a and formed to extend horizontally with the same thickness as the pair of left and right rear contact portions 72B. The portions of the pair of left and right locking pieces 76A near the tip ends 76Aa are formed in a concave shape so as to surround the tip ends 76Aa.

[0152] Next, the operation of this embodiment will be described.

[0153] The image projection device 10X according to this embodiment reflects light emitted from an image generation unit 20 toward an image display unit 102A by a reflecting mirror 40X. The image generation unit 20 includes a liquid crystal panel 22, an optical unit 30X that irradiates the liquid crystal panel 22 with backlight, and a panel support member 70 that supports the liquid crystal panel 22. The panel support member 70 has an opening 70a that allows the backlight emitted from the optical unit 30X to pass through toward the reflecting mirror 40X. This makes it easy for the backlight emitted from the optical unit 30X to reach the reflecting mirror 40X via the liquid crystal panel 22.

[0154] A pair of left and right engagement portions 72 that engage with both side edges of the liquid crystal panel 22 are formed in portions of the panel support member 70 located on the left and right sides of the opening 70a. The liquid crystal panel 22 is supported by the panel support member 70 by sliding the liquid crystal panel 22 relative to the panel support member 70 and engaging with the pair of left and right engagement portions 72, and the following effects can be obtained.

[0155] That is, in order to position the liquid crystal panel 22 with high positional accuracy relative to the optical unit 30X, the configuration of the panel support member 70 can be simplified compared to a configuration in which a pair of left and right support members, which are arranged on both the front and rear sides of the liquid crystal panel 22, are fixed with screws at multiple locations. This allows the image projection device 10X to be configured inexpensively.

[0156] As described above, according to this embodiment, in the image projection device 10X, the liquid crystal panel 22 of the image generation unit 20 can be positioned with high positional accuracy relative to the optical unit 30X with an inexpensive configuration.

[0157] In this embodiment, each of the pair of left and right engagement portions 72 is configured such that a front contact portion 72A that contacts the front surface of the liquid crystal panel 22 and a rear contact portion 72B that contacts the rear surface of the liquid crystal panel 22 are alternately formed at different positions in the sliding direction of the liquid crystal panel 22. This makes it easy to mold the panel support member 70, and enables the liquid crystal panel 22 to be efficiently clamped from both the front and rear sides.

[0158] In the panel support member 70 of this embodiment, a positioning portion 74 is formed at a portion located forward of the opening 70a in the sliding direction, which abuts against the front edge of the liquid crystal panel 22 in the sliding direction to position the liquid crystal panel 22 in the sliding direction. This improves the positioning accuracy of the liquid crystal panel 22.

[0159] Furthermore, the panel support member 70 of this embodiment is provided with a holding structure 76 at a location located rearward of the opening 70a in the sliding direction, which holds the liquid crystal panel 22 in a position relative to the sliding direction by engaging with the rear edge of the liquid crystal panel 22 in the sliding direction. This makes it possible to maintain the liquid crystal panel 22 stably positioned relative to the panel support member 70.

[0160] The holding structure 76 has a pair of left and right locking pieces 76A. When the liquid crystal panel 22 is slid upward relative to the panel support member 70, the pair of left and right locking pieces 76A are flexibly deformed with their tip portions 76Aa abutting the rear surface of the liquid crystal panel 22. Furthermore, when the liquid crystal panel 22 is slid to a position where it abuts against the positioning portion 74 of the panel support member 70, the tip portions 76Aa are configured to engage with the rear edge of the liquid crystal panel 22 in the sliding direction. This allows the liquid crystal panel 22 to be easily attached to the panel support member 70, while maintaining a stable positioning state.

[0161] In this embodiment, the liquid crystal panel 22 is supported by the panel support member 70 in a state inclined forward with respect to a vertical plane perpendicular to the front-to-rear direction of the device. Therefore, sunlight S that enters the internal space 12 of the housing 50 and is reflected by the reflecting mirror 40X can be prevented from reflecting off the liquid crystal panel 22 and becoming stray light that travels in a direction along the optical path R. Furthermore, sunlight S can be effectively prevented from reaching the image generation unit 20 as direct light.

[0162] In the above embodiment, the liquid crystal panel 22 is configured to slide from below relative to the panel support member 70, but it may also be slid from another direction (for example, from above or from either the left or right direction).

[0163] In the above embodiment, the image projection device 10X includes a single reflecting mirror 40X, but the image projection device 10X may include a plurality of reflecting mirrors that sequentially reflect the light emitted from the image generation unit 20 toward the image display section 102A of the front windshield 102. Even when such a configuration is adopted, it is possible to obtain the same effects as in the above embodiment.

[0164] Next, a modification of the second embodiment will be described.

[0165] First, a first modification of the second embodiment will be described.

[0166] FIG. 17 is a perspective view showing the panel support member 170 of the image projection device according to this modified example, illustrating how it is assembled.

[0167] 17 , the panel support member 170 according to this modification also has a pair of left and right engagement portions 172 each configured as a front contact portion 172A that contacts the front surface of the liquid crystal panel 22 and a rear contact portion 172B that contacts the rear surface of the liquid crystal panel 22. Furthermore, the front contact portion 172A and the rear contact portion 172B are alternately formed at different positions in the sliding direction of the liquid crystal panel 22.

[0168] In the panel support member 170 of this modified example, a positioning portion 174 is formed in a portion located forward of the opening 170a in the sliding direction. A holding structure 176 is provided in a portion located rearward of the opening 170a in the sliding direction. The configuration of the holding structure 176 differs from that of the above embodiment.

[0169] That is, the retaining structure 176 of this modified example has a pair of left and right wedge-shaped protrusions 176A formed on the front surfaces of the lower ends of the pair of left and right rear contact portions 172B located on the lower side. Each of the pair of left and right wedge-shaped protrusions 176A has a surface shape that gently slopes rearward in the sliding direction and steeply slopes forward in the sliding direction.

[0170] When the liquid crystal panel 22 is slid upward relative to the panel support member 170, the rear edge in the sliding direction rides over the pair of left and right wedge-shaped protrusions 176A and engages with the pair of left and right wedge-shaped protrusions 176A.

[0171] When the configuration of this modification is adopted, a slight load is applied to the liquid crystal panel 22 when it is slid upward due to contact with the pair of left and right wedge-shaped protrusions 176A, compared to the case of the above embodiment. However, the configuration of the panel support member 170 is simplified and substantially the same effects as the case of the above embodiment can be obtained.

[0172] Next, a second modification of the second embodiment will be described.

[0173] FIG. 18 is a front view showing a panel support member 270 of an image projection device according to this modified example, illustrating how a liquid crystal panel is assembled to the panel support member.

[0174] As shown in FIG. 18, the basic configuration of a panel support member 270 according to this modification is the same as that of the above embodiment, but the configuration of the pair of left and right engaging portions 272 is partially different from that of the above embodiment.

[0175] That is, in the pair of left and right engagement portions 272 of the panel support member 270 of this modified example, front abutment portions 272A and rear abutment portions 272B are formed alternately at multiple locations in the sliding direction. Specifically, the front abutment portions 272A are formed at three locations in the sliding direction, and the rear abutment portions 272B are formed at four locations in the sliding direction. The three front abutment portions 272A and the four rear abutment portions 272B are formed in positions that do not overlap each other when viewed from the front of the device.

[0176] In the panel support member 270 according to this modification, a holding structure 276 substantially similar to that in the above embodiment is provided at a location located rearward (i.e., downward) from the opening 270a in the sliding direction.

[0177] That is, the holding structure 276 has a pair of left and right locking pieces 276A extending in an L-shape from a pair of left and right rear surface abutment portions 272B formed at the lower end positions of the opening 270a. When the liquid crystal panel 22 is slid upward relative to the panel support member 270, the pair of left and right locking pieces 276A are flexed and deformed, and tip portions 276Aa abut the rear surface of the liquid crystal panel 22, and then engage with the rear edge of the liquid crystal panel 22 in the sliding direction.

[0178] However, in the retaining structure 276 of this modified example, the pair of left and right locking pieces 276A are formed shorter than in the above embodiment (although it is also possible to adopt a configuration in which they are not formed in this manner).

[0179] Even when the configuration of this modified example is adopted, substantially the same effects as those in the above embodiment can be obtained.

[0180] In addition, in this modified example, each of the pair of left and right engagement portions 272 is configured so that front abutment portions 272A and rear abutment portions 272B are formed at multiple locations in the sliding direction, thereby achieving the following effects.

[0181] That is, when both side edges of the liquid crystal panel 22 are engaged with the pair of left and right engagement portions 272, the liquid crystal panel 22 receives a pressing force from the front side of the device when it abuts against the front abutment portion 272A, and also receives a pressing force from the rear side of the device when it abuts against the rear abutment portion 272B. Therefore, there is a risk that the liquid crystal panel 22 may be deflected and deformed by the application of opposing pressing forces at different positions in the sliding direction.

[0182] In this modification, the pair of left and right engagement portions 272 are each configured such that front contact portions 272A and rear contact portions 272B are alternately formed at multiple locations in the sliding direction. This allows the pressing forces from the front side of the device and the rear side of the device to be dispersed and reduced among multiple locations in the sliding direction. This minimizes the risk of bending deformation of the liquid crystal panel 22 supported by the panel support member 270.

[0183] In the above-mentioned second modified example, it was described that the front abutment portions 272A are formed in three locations and the rear abutment portions 272B are formed in four locations, but it is also possible to configure the formation locations to be set to values ​​other than these.

[0184] The numerical values ​​shown in the above embodiment and its modified examples are merely examples, and may be set to different values ​​as appropriate.

[0185] Furthermore, the present disclosure is not limited to the configurations described in the above-described embodiment and its modified examples, and configurations with various other modifications can be adopted.

[0186] The configurations described in the items listed below also constitute part of the present disclosure. Item 6: An image projection device configured to project a display image on an image display section, comprising: an image generation unit that generates the display image; and a reflecting mirror that reflects light emitted from the image generation unit toward the image display section, wherein the image generation unit comprises a liquid crystal panel, an optical unit that irradiates the liquid crystal panel with backlight, and a panel support member that supports the liquid crystal panel, wherein an opening is formed in the panel support member to allow backlight irradiation light from the optical unit to pass toward the reflecting mirror, and a pair of engagement portions that engage with both side edges of the liquid crystal panel are formed in portions of the panel support member located on both sides of the opening, and wherein the liquid crystal panel is supported by the panel support member by sliding the liquid crystal panel relative to the panel support member to engage with the pair of engagement portions. Item 7: The image projection device according to Item 6, wherein each of the pair of engaging portions has a front abutment portion that abuts against the front surface of the liquid crystal panel and a rear abutment portion that abuts against the rear surface of the liquid crystal panel, and the front abutment portion and the rear abutment portion are alternately formed at different positions in the sliding direction of the liquid crystal panel. Item 8: The image projection device according to Item 7, wherein the front abutment portion and the rear abutment portion are formed at a plurality of locations in the sliding direction. Item 9: The image projection device according to any one of Items 6 to 8, wherein a positioning portion that positions the liquid crystal panel in the sliding direction by abutting against a front edge portion of the liquid crystal panel in the sliding direction is formed in a portion of the panel support member that is located forward of the opening in the sliding direction. Item 10: The image projection device according to any one of Items 6 to 9, wherein a holding structure that holds the liquid crystal panel in a positioned state in the sliding direction by engaging with a rear edge portion of the liquid crystal panel in the sliding direction is provided in a portion of the panel support member that is located rearward of the opening in the sliding direction.

[0187] This application claims priority based on Japanese Application No. 2023-117450 filed on July 19, 2023 and Japanese Application No. 2023-117739 filed on July 19, 2023. All of the contents of the above-mentioned Japanese applications are incorporated herein by reference.

Claims

1. An image projection device configured to project a display image onto an image display section, comprising: an image generating unit which generates the display image; a reflecting mirror which reflects light emitted from the image generating unit towards the image display section; and a housing which contains the reflecting mirror; the reflecting mirror is supported rotatably about an axis extending in the left-right direction relative to the housing; an axle portion extending in the axial direction is formed at a side end of the reflecting mirror; the housing is formed with a mounting portion on which the axle portion is placed; a positioning member which positions the axle portion in the up-down direction is attached to the housing; the positioning member is comprised of a leaf spring having a base portion and a lever portion; and the positioning member is configured such that the lever portion elastically presses the axle portion from above while the base portion is engaged with the housing.

2. The image projection device of claim 1, wherein the base portion comprises a horizontal surface portion extending horizontally and a pair of front and rear vertical surface portions extending vertically downward from the front and rear end positions of the horizontal surface portion, an opening extending in the front and rear directions is formed in the horizontal surface portion, and the lever portion is formed so as to extend in a downwardly convex curved state toward inside the opening from the front or rear end position of the opening.

3. An image projection device as described in claim 2, wherein a second lever portion extending downward is formed at a midpoint in the front-to-rear direction on the horizontal surface portion, and the second lever portion is configured to abut against a tip surface of the shaft portion and elastically press the shaft portion in the axial direction.

4. An image projection device as described in claim 2 or 3, wherein a second opening is formed in each of the pair of front and rear vertical surface portions, a locking piece portion is formed in each of the pair of front and rear vertical surface portions extending from a lower end position of the second opening toward inside the second opening, the pair of front and rear locking piece portions are formed to extend at an angle away from each other in the vertical upward direction, and the positioning member is locked to the housing at the pair of front and rear locking piece portions.

5. An image projection device as described in claim 4, wherein insertion holes for inserting the pair of front and rear vertical surface portions are formed on both the front and rear sides of the placement portion in the housing, and locking portions for locking the positioning member by abutting the upper edges of the pair of front and rear locking piece portions are formed in the vicinity of the pair of front and rear insertion holes in the housing.

6. An image projection device configured to project a display image onto an image display section, comprising: an image generation unit which generates the display image; and a reflecting mirror which reflects light emitted from the image generation unit towards the image display section, the image generation unit comprising: a liquid crystal panel; an optical unit which irradiates the liquid crystal panel with backlight; and a panel support member which supports the liquid crystal panel, the panel support member having an opening which allows backlight irradiation light from the optical unit to pass towards the reflecting mirror, the panel support member having a pair of engagement portions which engage with both side edges of the liquid crystal panel at portions on either side of the opening, the liquid crystal panel being supported by the panel support member by sliding the liquid crystal panel relative to the panel support member to engage with the pair of engagement portions.

7. An image projection device as described in claim 6, wherein each of the pair of engagement portions has a front abutment portion that abuts against the front surface of the liquid crystal panel and a rear abutment portion that abuts against the rear surface of the liquid crystal panel, and the front abutment portion and the rear abutment portion are alternately formed at different positions with respect to the sliding direction of the liquid crystal panel.

8. The image projection device according to claim 7, wherein the front contact portion and the rear contact portion are formed at a plurality of positions in the sliding direction.

9. An image projection device as described in any one of claims 6 to 8, wherein a positioning portion is formed in a portion of the panel support member that is located forward in the sliding direction from the opening, and that positions the liquid crystal panel in the sliding direction by abutting against the sliding direction front end edge of the liquid crystal panel.

10. An image projection device as described in claim 6, wherein a holding structure is provided at a portion of the panel support member located rearward in the sliding direction from the opening, for holding the liquid crystal panel in a position relative to the sliding direction by engaging with the rear end edge of the liquid crystal panel in the sliding direction.

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