Head-up display device

Abstract

The present invention provides a head-up display device capable of suppressing the positional displacement of a display unit. A head-up display device 100 comprises: a backlight unit 15 that emits illumination light; a display unit 10 that receives the illumination light from the backlight unit 15 and emits display light L; and a housing 60 that houses the backlight unit 15 and the display unit 10. The housing 60 is provided with a boundary plate part 68v having a light passage hole 68a through which the illumination light traveling from the backlight unit 15 to the display unit 10 passes. The display unit 10 is provided on the inner bottom surface 68b side of the housing 60, the inner bottom surface being an example of a first surface of the boundary plate part 68v. The backlight unit 15 is provided on the outer bottom surface 68c side of the housing 60, the outer bottom surface being an example of a second surface of the boundary plate part 68v on the reverse side of the inner bottom surface 68b side.

Description

Technical Field

[0001] The present disclosure relates to a head-up display device.

Background Art

[0002] For example, the head-up display device described in Patent Document 1 includes a display device that emits display light and a case that houses the display device in an internal space. This display device includes a light source and a display panel that forms display light by transmitting illumination light from the light source.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the configuration of the above Patent Document 1, since the entire display device having both a light source and a display panel is housed in the case, displacement of the display panel with respect to the case is likely to occur.

[0005] The present disclosure has been made in view of the above actual situation, and an object thereof is to provide a head-up display device capable of suppressing displacement of a display unit.

Means for Solving the Problems

[0006] To achieve the above object, the head-up display device according to the present disclosure includes a backlight unit that emits illumination light, a display unit that receives the illumination light from the backlight unit and emits display light, and a housing that houses the backlight unit and the display unit. The housing includes a boundary plate portion having a light passage hole through which the illumination light travels from the backlight unit toward the display unit. The display unit is provided on the first surface side of the boundary plate portion, and the backlight unit is provided on the second surface side of the boundary plate portion, which is opposite to the first surface side.

Effect of the Invention

[0007] According to the present disclosure, in a head-up display device, displacement of the display unit can be suppressed.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Mode for Carrying Out the Invention

[0009] An embodiment of a head-up display device according to the present disclosure will be described with reference to the drawings. As shown in FIG. 1, the head-up display device 100 is mounted in the dashboard of the vehicle 5. The head-up display device 100 emits display light L representing an image toward the front glass 6, which is an example of a projection member of the vehicle 5. The display light L is reflected by the front glass 6 and reaches the viewer 1 (mainly the driver of the vehicle 5). Thereby, the head-up display device 100 displays a virtual image V including vehicle information so as to be visible to the viewer 1.

[0010] As shown in FIG. 2, the head-up display device 100 includes a display unit 10, a backlight unit 15, a heat sink 16, a reflector 20, a concave mirror 30, a first mirror holder 69, a second mirror holder 63, a housing 60, a mirror drive unit 78, a control board 70, and screws 65a, 65b, 65c, 65d which are fixing means, and a light entry suppression ring 65e as shown in FIGS. 11 and 17.

[0011] As shown in FIG. 2, the display unit 10 emits display light L representing an image under the control of the control board 70. The specific configuration of the display unit 10 will be described later.

[0012] The reflector 20 is a plane mirror that reflects the display light L from the display unit 10 toward the concave mirror 30. Note that the reflector 20 may be a concave mirror. The second mirror holder 63 is formed of resin and holds the reflector 20 with the reflecting surface of the reflector 20 exposed. The second mirror holder 63 is installed in a middle case 62 described later.

[0013] As shown in FIG. 2, the concave mirror 30 reflects the display light L reflected by the reflector 20 while expanding it toward the front glass 6 (see FIG. 1). The first mirror holder 69 is formed of resin and supports the concave mirror 30 so as to be rotatable about a rotation axis Ax.

[0014] The mirror drive unit 78 changes the projection position of the display light L with respect to the viewer 1 in the height direction by rotating the concave mirror 30 about the rotation axis Ax via the first mirror holder 69 under the control of the control board 70.

[0015] As shown in FIG. 2, the housing 60 is formed of resin. Each component of the head-up display device 100 is housed in the housing 60. An opening 61h is formed in the housing 60 at a position facing the front glass 6 (see FIG. 1). The housing 60 includes a curved plate-shaped window portion 50 that closes the opening 61h. The window portion 50 is made of a light-transmissive resin such as acrylic through which the display light L passes.

[0016] Specifically, the housing 60 includes an upper case 61, a middle case 62, a lower case 68, and a board cover 67.

[0017] The lower case 68 is box-shaped and opens upward. Inside the lower case 68, a second mirror holder 63 that holds the reflector 20, a first mirror holder 69 that holds the concave mirror 30, the middle case 62, and the display unit 10 are accommodated. The lower case 68 is a bottom plate and includes a boundary plate portion 68v that partitions the display unit 10 and the backlight unit 15. The surface of the boundary plate portion 68v facing the display unit 10 is the inner bottom surface 68b of the lower case 68, and the surface of the boundary plate portion 68v facing the backlight unit 15 is the outer bottom surface 68c of the lower case 68. The backlight unit 15, the control board 70, and the board cover 67 are mounted on the outer bottom surface 68c of the lower case 68. As shown in FIGS. 3 and 4, through light passage holes 68a and cable passage holes 68d are formed in the boundary plate portion 68v of the lower case 68, respectively. The light passage holes 68a are rectangular. The display unit 10 is fixed to a portion of the inner bottom surface 68b of the lower case 68 corresponding to the light passage holes 68a. The backlight unit 15 is fixed to a portion of the outer bottom surface 68c of the lower case 68 corresponding to the light passage holes 68a.

[0018] The cable passage holes 68d are located around the light passage holes 68a and are rectangular. As shown in FIG. 6, the cable passage holes 68d are formed between the display unit 10 and the control board 70. Cables 12k and cable guides 11u2, which will be described later, pass through the cable passage holes 68d.

[0019] As shown in FIG. 11, convex fixing portions 68e and 68f are formed on the inner bottom surface 68b of the lower case 68. The fixing portions 68e and 68f are positioned so as to sandwich the cable through-hole 68d along the longitudinal direction of the display panel 12 described later. A screw hole (not shown) into which the pin 68g and the screw 65a are screwed is formed on the upper surface of the fixing portion 68e. A screw hole (not shown) into which the pin 68h and the screw 65b are screwed is formed on the upper surface of the fixing portion 68f. Further, a screw hole (not shown) into which the pin 68i and the screw 65c are screwed is formed on the inner bottom surface 68b of the lower case 68. The screw hole (not shown) into which the pin 68i and the screw 65c are screwed is located on the side opposite to the fixing portions 68e and 68f through the display panel 12 in the short-side direction of the display panel 12 described later.

[0020] As shown in FIG. 5, the lower case 68 includes a plurality of vehicle body attachment portions 68j, 68k, and 68m formed on the outer periphery of the lower case 68. The vehicle body attachment portions 68j, 68k, and 68m are portions fixed to the vehicle body which is an attachment target to which the head-up display device 100 is attached. The vehicle body attachment portions 68j, 68k, and 68m are provided on the outer side surface of the lower case 68 and each has a rectangular plate shape. The vehicle body attachment portions 68j, 68k, and 68m extend in a direction intersecting the outer side surface of the lower case 68. One screw through-hole 68j1, 68k1, and 68m1 is formed in each of the vehicle body attachment portions 68j, 68k, and 68m. Screws (not shown) for fixing the vehicle body attachment portions 68j, 68k, and 68m to the vehicle body pass through the screw through-holes 68j1, 68k1, and 68m1. Further, the vehicle body attachment portion 68j includes a positioning pin 68j2 for positioning the vehicle body attachment portion 68j on the vehicle body. The positioning pin 68j2 is formed in a substantially cylindrical shape on the surface on the heat sink 16 side and is formed so as to be fitted into a positioning hole (not shown) of the vehicle body.

[0021] As shown in FIGS. 2 and 3, the middle case 62 is housed in the lower case 68 and forms an optical path space Sc through which the display light L passes within the lower case 68. The middle case 62 is a blind cover that hides the members that cause stray light from the optical path space Sc. The upper case 61 functions as a lid for the lower case 68 so as to close the lower case 68. An opening 61h is formed in the upper case 61, and the window portion 50 is attached thereto.

[0022] As shown in FIG. 13, the display unit 10 includes a holder cover 11u, a middle holder 11m, a panel holder 11d, a display panel 12, a diffusion plate 13, and a light-transmitting member 14. The light-transmitting member 14 has a rectangular, in this example, rectangular plate shape. As enlarged and shown at the upper part of FIG. 6, the light-transmitting member 14 includes a base material 14a formed of a light-transmitting member such as glass, a polarizing layer 14b formed on the back surface of the base material 14a facing the display panel 12, and a high retardation layer 14c formed on the front surface of the base material 14a.

[0023] The high retardation layer 14c cuts off external light such as sunlight and suppresses the temperature rise of the display panel 12 due to the external light. As the high retardation layer 14c, a high retardation film with a retardation value of 3000 nanometers or more, preferably 3000 to 30000 nanometers, can be applied. Note that when the retardation value is less than 3000 nanometers, when observing the display (virtual image) through polarized sunglasses, a strong interference color is exhibited, so good visibility cannot be ensured. Further, the high retardation layer 14c has a function as a retardation film that further enhances the light reflection efficiency of the display light L (that is, the S-wave component among the P-wave component and the S-wave component included in the display light L) reflected on the viewer 1 side by the front glass 6. The polarizing layer 14b is a polarizing plate that performs circular polarization such as elliptical polarization on the linearly polarized display light L that has passed through the display panel 12. By circularly polarizing the display light L by the polarizing layer 14b, the polarization of the P-wave and the S-wave included in the display light L is reduced, and the visibility of the virtual image V when wearing polarized glasses such as sunglasses can be improved.

[0024] As shown in FIG. 6, the light-transmitting member 14 is held at an angle different from that of the display panel 12 by the middle holder 11m and the panel holder 11d. By opposing the light-transmitting member 14 and the display panel 12 at different angles, for example, when a part of the display light L from the display panel 12 is reflected on the back surface of the light-transmitting member 14, it is suppressed that this reflected light is reflected again toward the light-transmitting member 14 on the front surface of the display panel 12. Thereby, it is suppressed that the virtual image V is displayed doubly, and the display quality of the virtual image V can be improved. As an example, the angle α of the light-transmitting member 14 with respect to the reference direction perpendicular to the traveling direction of the illumination light emitted from the backlight unit 15 is set larger than the angle β of the display panel 12 with respect to this reference direction. For example, the angle α is set to 36° to 40°, and the angle β is set to 28° to 32°. More preferably, the angle α is set to 38° and the angle β is set to 30°.

[0025] As shown in FIG. 9, the display panel 12 includes a panel main body portion 12a, a frame portion 12b, and a cable 12k. The panel main body portion 12a is formed of a TFT (Thin Film Transistor) type liquid crystal panel. The panel main body portion 12a has a rectangular, in this example, rectangular plate shape. The panel main body portion 12a receives illumination light from the backlight unit 15 (see FIG. 2) and emits display light L.

[0026] The frame portion 12b is a metal bezel surrounding the outer periphery of the panel main body portion 12a. The frame portion 12b includes a wide portion 12b1 and a narrow portion 12b2. The wide portion 12b1 is located on the upper side, which is one of the two long sides of the frame portion 12b. The narrow portion 12b2 is located on the lower side, which is the other of the two long sides of the frame portion 12b. The width W1 of the wide portion 12b1 is formed wider than the width W2 of the narrow portion 12b2. The widths W1 and W2 are lengths along the short side direction of the frame portion 12b. The widths of the two short sides of the frame portion 12b are substantially the same as the width W2 of the narrow portion 12b2.

[0027] As shown in FIG. 6, the cable 12k is a flexible and strip-shaped flexible flat cable. The cable 12k electrically connects between the panel main body 12a and the control board 70. The proximal end of the cable 12k is connected to the side surface of the panel main body 12a, and the distal end of the cable 12k on the side opposite to the panel main body 12a is connected to the connector 71 on the control board 70. The cable 12k passes through a cable through-hole 68d (to be described later) of the lower case 68. The control board 70 transmits and receives various signals such as control signals to and from the display panel 12 via the cable 12k. As shown in FIG. 11, the proximal end of the cable 12k is fixed to the central portion of the side surface corresponding to the wide portion 12b1 among the side surfaces of the display panel 12.

[0028] As shown in FIG. 6, the diffusion plate 13 is provided on the back surface side of the display panel 12, that is, on the incident surface side of the illumination light, and diffuses the light from the backlight unit 15.

[0029] As shown in FIG. 13, the holder cover 11u, the middle holder 11m, and the panel holder 11d are each formed of resin. The holder cover 11u is attached to the panel holder 11d that holds the display panel 12 and the diffusion plate 13 with the middle holder 11m that holds the light-transmitting member 14 interposed therebetween. As shown in FIG. 7, the holder cover 11u includes a main body frame portion 11u1 and a cable guide portion 11u2. The main body frame portion 11u1 forms a frame shape along the outer periphery of the display unit 10. As shown in FIG. 12, the main body frame portion 11u1 includes a base plate portion 11u3, an inner peripheral side wall portion 11u4, an outer peripheral side wall portion 11u6, and a pressing portion 11u5. The base plate portion 11u3 extends along the light-transmitting member 14. The outer peripheral side wall portion 11u6 is located on the outer peripheral side of the main body frame portion 11u1 and extends toward the panel holder 11d in a direction intersecting the base plate portion 11u3. The inner peripheral side wall portion 11u4 is located on the inner peripheral side of the main body frame portion 11u1 and extends toward the upper surface of the light-transmitting member 14 in a direction intersecting the base plate portion 11u3. The pressing part 11u5 is formed in a rod shape on the surface of the base plate part 11u3 facing the display panel 12. The pressing part 11u5 passes through the through hole 11m1 formed in the middle holder 11m, and the tip of the pressing part 11u5 is in contact with the wide part 12b1 of the frame part 12b of the display panel 12. Thereby, the display panel 12 is sandwiched between the pressing part 11u5 and the panel holder 11d. As shown in FIG. 13, on the outer surface of the outer peripheral side wall part 11u6, a plurality of convex parts 11ut into which mounting hooks 11df (to be described later) of the panel holder 11d are fitted are formed.

[0030] As shown in FIG. 7, the cable guide part 11u2 is connected to the main body frame part 11u1 and guides the cable 12k toward the control board 70. The cable guide part 11u2 is connected to the center of the long side of the main body frame part 11u1 and passes through the cable through hole 68d of the lower case 68 as shown in FIG. 6. The cable guide part 11u2 has a rectangular plate shape extending from the main body frame part 11u1 toward the cable through hole 68d. The cable guide part 11u2 extends obliquely with respect to the inner bottom surface 68b of the lower case 68. The cable 12k is located on the display panel 12 side of the cable guide part 11u2. The tip of the cable guide part 11u2 is curved in the direction along the control board 70 and is positioned to face the connector 71. In addition to the function of guiding the cable 12k toward the control board 70, the cable guide part 11u2 has a function of hiding the cable 12k in order to suppress the generation of stray light. As shown in FIG. 7, the cable guide part 11u2 includes a plurality of ribs 11ur extending along the outer surface of the cable guide part 11u2. Each rib 11ur extends along the edge extending in the longitudinal direction of the cable guide part 11u2. The ribs 11ur are formed to increase the strength of the cable guide part 11u2.

[0031] As shown in Fig. 13, the middle holder 11m has a frame shape along the outer periphery of the light-transmitting member 14. The middle holder 11m supports the light-transmitting member 14 from the lower surface of the light-transmitting member 14. The middle holder 11m is installed on the panel holder 11d via the display panel 12 and the diffusion plate 13 and is housed within the holder cover 11u. As shown in Fig. 6, the middle holder 11m is configured such that the installation surface on which the light-transmitting member 14 is installed is inclined in order to support the light-transmitting member 14 in an inclined posture with respect to the display panel 12.

[0032] As shown in Fig. 8, the panel holder 11d includes a main body frame portion 11d1, pressing portions 11d2, 11d3, 11d4, positioning portions 11d5, 11d6, 11d7, an elastic support portion 11d8, an installation convex portion 11d9, a mounting hook 11df, and attachment portions 11da, 11dd, 11dg.

[0033] The main body frame portion 11d1 has a rectangular frame shape along the outer periphery of the display panel 12 (see Fig. 9). A light passage hole 11dh through which illumination light passes is formed at the center of the main body frame portion 11d1. As shown in Fig. 9, the positioning portions 11d5, 11d6, 11d7 are provided on the upper surface of the main body frame portion 11d1. The positioning portions 11d5, 11d6 are respectively positioned corresponding to two corner portions of the display panel 12. In this example, the positioning portions 11d5, 11d6 are positioned corresponding to two corner portions at both ends of the wide portion 12b1. The positioning portions 11d5, 11d6 each include an L-shaped columnar portion 11dl and a roof portion 11dy. The L-shaped columnar portion 11dl has an L-shaped columnar shape corresponding to the corner portion of the display panel 12. The L-shaped columnar portion 11dl has a function of positioning the display panel 12 in its surface direction. The roof portion 11dy is provided at a part of the upper end of the L-shaped columnar portion 11dl and extends along the same direction as the display panel 12. The roof portion 11dy is positioned to face the upper surface of the frame portion 12b of the display panel 12. The roof portion 11dy has a function of positioning the display panel 12 in the direction perpendicular to its surface. The positioning portion 11d7 contacts the side surface extending in the short side direction of the display panel 12. In this example, the positioning portion 11d7 is provided at a position farther from the positioning portion 11d6 than the center of this side surface.

[0034] The pressing portions 11d2, 11d3, 11d4 are provided on the upper surface of the main body frame portion 11d1, contact the side surface of the display panel 12, and press the display panel 12 toward the positioning portions 11d5, 11d6, 11d7. The pressing portion 11d2 is positioned so as to sandwich the display panel 12 in the longitudinal direction of the display panel 12 between it and the positioning portion 11d7. The pressing portion 11d2 is provided at a position different from that of the positioning portion 11d7 in the short side direction of the display panel 12. In this example, the pressing portion 11d2 is provided at the center of the side surface extending in the short side direction of the display panel 12. The pressing portions 11d3, 11d4 are positioned so as to sandwich the display panel 12 in the short side direction of the display panel 12 between them and the positioning portions 11d5, 11d6. The pressing portions 11d3, 11d4 are provided at positions different from those of the positioning portions 11d5, 11d6 in the longitudinal direction of the display panel 12. The pressing portions 11d3, 11d4 are arranged along the longitudinal direction so as to sandwich the central portion in the longitudinal direction of the display panel 12.

[0035] As shown in FIG. 10, the pressing portion 11d2 includes a leaf spring portion 11dk and a claw portion 11dt provided at the tip of the leaf spring portion 11dk. The claw portion 11dt presses the side surface of the display panel 12 by receiving the elastic force from the leaf spring portion 11dk. The claw portion 11dt is provided with an inclined surface 11ds at the upper end portion on the display panel 12 side. The inclined surface 11ds inclines so as to approach the display panel 12 as it approaches the leaf spring portion 11dk. When the display panel 12 is assembled to the panel holder 11d, the display panel 12 slides on the inclined surface 11ds and the leaf spring portion 11dk elastically retracts, so that the display panel 12 can be inserted between the pressing portions 11d2, 11d3, 11d4 and the positioning portions 11d5, 11d6, 11d7. The pressing portions 11d3, 11d4 have the same configuration as the pressing portion 11d2.

[0036] As shown in FIG. 8, the elastic support portion 11d8 is provided on the upper surface of the main body frame portion 11d1 and elastically supports the lower surface of the frame portion 12b of the display panel 12. The installation convex portion 11d9 is provided convexly on the upper surface of the main body frame portion 11d1 and is formed in an L shape corresponding to each corner portion of the light passage hole 11dh. The installation convex portion 11d9 positions the display panel 12 in its thickness direction by coming into contact with the frame portion 12b of the display panel 12.

[0037] The plurality of mounting hooks 11df are provided on the outer peripheral edge portion of the main body frame portion 11d1 and fit into the convex portion 11ut (see FIG. 13) of the holder cover 11u. As shown in FIG. 9, the plurality of attachment portions 11da, 11dd, 11dg are provided on the outer peripheral edge portion of the main body frame portion 11d1 and are plate-shaped. As shown in FIG. 11, the attachment portion 11da is fixed to the upper surface of the fixing portion 68e, the attachment portion 11dd is fixed to the upper surface of the fixing portion 68f, and the attachment portion 11dg is fixed around the pin 68i on the inner bottom surface 68b of the lower case 68. Thereby, the panel holder 11d is in an inclined posture with respect to the inner bottom surface 68b of the lower case 68.

[0038] Specifically, as shown in FIG. 9, the attachment portion 11da is located at the corner corresponding to the positioning portion 11d5 among the corners of the main body frame portion 11d1. The attachment portion 11da is formed with a pin through hole 11db and a screw through hole 11dc. The attachment portion 11dd is located at the corner corresponding to the positioning portion 11d6 among the corners of the main body frame portion 11d1. The attachment portion 11dd is formed with a pin through hole 11de and a screw through hole 11df. The attachment portion 11dg is located at the center of the side surface corresponding to the pressing portions 11d3, 11d4 among the side surfaces of the main body frame portion 11d1. The attachment portion 11dg is formed with a pin through hole 11di and a screw through hole 11dj. As shown in FIG. 11, a pin 68g fits into the pin through-hole 11db, and the shaft portion of a screw 65a passes through the screw through-hole 11dc (see FIG. 9). A pin 68h fits into the pin through-hole 11de, and the shaft portion of a screw 65b passes through the screw through-hole 11df (see FIG. 9). A pin 68i fits into the pin through-hole 11di, and the shaft portion of a screw 65c passes through the screw through-hole 11dj (see FIG. 9).

[0039] As shown in FIG. 14, the backlight unit 15 includes a lens cover 17a, a light guide case 17b, a condenser lens 18a, lenticular lenses 18b and 18c, a light source substrate 19a, a plurality of light sources 19b, and a heat conduction sheet 19c. The plurality of light sources 19b are each composed of a plurality of LEDs (Light Emitting Diodes) and are mounted on the surface of the light source substrate 19a facing the condenser lens 18a. The heat conduction sheet 19c is provided on the lower surface of the light source substrate 19a and transfers the heat generated by the light source 19b to the heat sink 16. The condenser lens 18a collimates the light emitted by each light source 19b. The lenticular lenses 18b and 18c emit illumination light that diffuses the light passing through the condenser lens 18a in the longitudinal and transverse directions of the lenticular lenses 18b and 18c.

[0040] The lens cover 17a and the light guide case 17b are formed of resin. The light guide case 17b has a rectangular cylindrical shape surrounding the condenser lens 18a, the lenticular lenses 18b and 18c, and the light source substrate 19a. A plurality of convex portions 17b1 are formed on the outer peripheral surface of the light guide case 17b.

[0041] As shown in FIG. 15, the light guide case 17b includes a plurality of fixing portions 17c. The plurality of fixing portions 17c are located below each corner portion of the light guide case 17b and are formed in a substantially cylindrical shape. As shown in FIG. 16, screw holes 17d are formed in the lower surface of each fixing portion 17c. Each fixing portion 17c is arranged so as to overlap with the lens cover 17a in the height direction H of the backlight unit 15. The height direction H is a direction along the traveling direction of the light emitted by the light source 19b.

[0042] As shown in FIG. 14, the lens cover 17a includes a frame portion 17a2 along the outer periphery of the lenticular lens 18c and a plurality of hooks 17a1 formed on the outer periphery of the frame portion 17a2. The frame portion 17a2 is formed to protrude in the light emission direction from the light emission surface of the lenticular lens 18c. Thereby, for example, even when the backlight unit 15 is installed such that the lenticular lens 18c faces the installation surface during the assembly process of the head-up display device 100, since the frame portion 17a2 contacts the installation surface, it is possible to avoid the lenticular lens 18c from contacting the installation surface and being damaged. Each of the plurality of hooks 17a1 fits into a corresponding one of the plurality of convex portions 17b1 of the light guide case 17b. Thereby, the lens cover 17a is fixed to the light guide case 17b.

[0043] As shown in FIG. 15, the heat sink 16 is provided to release the heat generated by the backlight unit 15 to the outside. The heat sink 16 includes a main body container portion 16a and a vehicle body mounting portion 16b. The main body container portion 16a is box-shaped for housing the backlight unit 15. A plurality of screw through holes 16a2 are formed in the bottom plate 16a1 of the main body container portion 16a where the backlight unit 15 is installed. The plurality of screw through holes 16a2 are respectively located opposite to the screw holes 17d (see FIG. 16) of the fixing portions 17c of the light guide case 17b. As shown in FIG. 16, the backlight unit 15 is fixed to the heat sink 16 by inserting the shaft portion of the screw 65d, which is a fixing means, into the screw through hole 16a2 and the screw hole 17d. The light entry suppression ring 65e is provided at a position on the outer periphery of the shaft portion of the screw 65d and in contact with the head of the screw 65d. The light entry suppression ring 65e has an outer diameter larger than that of the screw through hole 16a2 and an inner diameter smaller than that of the head of the screw 65d, and forms a flat ring shape. The light entry suppression ring 65e suppresses light from entering the screw through hole 16a2 from the outside of the heat sink 16. The light entry suppression ring 65e is, for example, a metal washer and also has a function of preventing the screw 65d from loosening.

[0044] As shown in FIG. 15, the vehicle body attachment portion 16b has a rectangular plate shape and is formed at the outer peripheral edge portion of the main body container portion 16a. The vehicle body attachment portion 16b is a portion fixed to the vehicle body. As shown in FIG. 5, the vehicle body attachment portion 16b overlaps with the vehicle body attachment portion 68m of the lower case 68. The vehicle body attachment portion 16b overlaps with the lower side of the vehicle body attachment portion 68m. Therefore, the metal vehicle body attachment portion 16b can enhance the rigidity of the resin vehicle body attachment portion 68m and thus the entire head-up display device 100, and the head-up display device 100 can be more firmly attached to the vehicle body. A screw through hole 16b1 through which a screw passes is formed in the vehicle body attachment portion 16b. The screw through hole 16b1 faces the screw through hole 68m1 of the vehicle body attachment portion 68m of the lower case 68. Further, a pin through hole 16b2 is formed in the vehicle body attachment portion 16b. Depending on the model of the head-up display device, positioning pins similar to the positioning pin 68j2 are formed in the vehicle body attachment portion 68m. In this case, this positioning pin passes through the pin through hole 16b2.

[0045] Next, a method for assembling the head-up display device 100 will be described. The following assembly is performed by a person or a work robot. First, a method for assembling the display unit 10 will be described. As shown in FIG. 13, a diffusion plate 13, a display panel 12, a middle holder 11m, and a light-transmitting member 14 are stacked in order on the upper surface of the panel holder 11d. Then, the holder cover 11u is attached to the panel holder 11d. At this time, by locking the attachment hook 11df to the convex portion 11ut, the holder cover 11u is fixed to the panel holder 11d. Thus, the assembly of the display unit 10 is completed. Next, as shown in FIG. 3, the display unit 10 is assembled to the lower case 68. Specifically, as shown in FIG. 11, a pin 68g is inserted through the pin through-hole 11db, a pin 68h is inserted through the pin through-hole 11de, and a pin 68i is inserted through the pin through-hole 11di. Thereby, the panel holder 11d is positioned on the inner bottom surface 68b of the lower case 68. Next, the shaft portions of the screws 65a, 65b, and 65c are passed through the screw through-holes 11dc, 11df, and 11dj (see FIG. 9) respectively, and are screwed into screw holes (not shown) of the lower case 68. Thereby, the panel holder 11d is fixed to the inner bottom surface 68b of the lower case 68 in an inclined posture. Thus, the assembly of the display unit 10 to the lower case 68 is completed. At this time, as shown in FIG. 3, the middle case 62, the first mirror holder 69 that holds the reflecting mirror 20, the second mirror holder 63 that holds the concave mirror 30, the mirror drive unit 78, etc. are accommodated in the lower case 68, and the upper case 61 is fitted into the lower case 68.

[0046] Next, a method for assembling the backlight unit 15 and the heat sink 16 to the lower case 68 will be described. As shown in FIG. 4, the lower case 68 is repeatedly pulled to expose the outer bottom surface 68c of the lower case 68. Then, the control board 70 is installed on the outer bottom surface 68c, and the cable 12k is connected to the control board 70. Next, the board cover 67 is attached to the lower case 68 so as to cover the control board 70. On the one hand, as shown in FIG. 15, the backlight unit 15 is set in the main body container portion 16a of the heat sink 16, and as shown in FIG. 17, the heat sink 16 is repeatedly turned to screw the screw 65d with the light entry suppression ring 65e mounted thereon, thereby fixing the backlight unit 15 in the heat sink 16. Then, as shown in FIGS. 2 and 4, the heat sink 16 and the backlight unit 15 are mounted around the light passage hole 68a on the outer bottom surface 68c of the lower case 68. Thus, the assembly of the backlight unit 15 and the heat sink 16 to the lower case 68 is completed. Thus, the assembly of the head-up display device 100 is completed. After assembly, the head-up display device 100 is attached to the vehicle body by fixing the vehicle body attachment portions 68j, 68k, 68m, 16b to the vehicle body with screws (not shown).

[0047] (Effect) According to the above-described embodiment, the following effects can be obtained. (1) The head-up display device 100 includes a backlight unit 15 that emits illumination light, a display unit 10 that emits display light L by receiving the illumination light from the backlight unit 15, and a housing 60 that houses the backlight unit 15 and the display unit 10. The housing 60 includes a boundary plate portion 68v having a light passage hole 68a through which the illumination light travels from the backlight unit 15 toward the display unit 10. The display unit 10 is provided on the inner bottom surface 68b side of the housing 60, which is an example of the first surface of the boundary plate portion 68v. The backlight unit 15 is provided on the outer bottom surface 68c side of the housing 60, which is an example of the second surface of the boundary plate portion 68v on the side opposite to the inner bottom surface 68b side. According to this configuration, since the display unit 10 is provided on the inner bottom surface 68b side, displacement of the display unit 10 with respect to the housing 60 can be suppressed. Therefore, the display quality of the virtual image V can be improved. Conventionally, since the display unit and the backlight unit are integrally formed, when this integrated unit is fixed in the housing, the position of the display unit is displaced due to the shape error and mounting error of the backlight unit. According to the above configuration, since the display unit 10 is provided separately from the backlight unit 15 on the inner bottom surface 68b side, the display unit 10 is not affected by the shape error and mounting error of the backlight unit 15.

[0048] (2) The display unit 10 includes a display panel 12 that emits display light L by receiving illumination light from the backlight unit 15, and a panel holder 11d on which the display panel 12 is installed. The panel holder 11d includes positioning portions 11d5, 11d6, 11d7 that contact the side surface of the display panel 12, and pressing portions 11d2, 11d3, 11d4 that press the display panel 12 toward the positioning portions 11d5, 11d6, 11d7. According to this configuration, the display panel 12 is positioned by the positioning portions 11d5, 11d6, 11d7 and the pressing portions 11d2, 11d3, 11d4 of the panel holder 11d. In this way, since the display panel 12 is positioned by the panel holder 11d which is a single member, it is less likely to be affected by the shape error and mounting error of other members. Therefore, displacement of the display panel 12 can be suppressed.

[0049] (3) The panel holder 11d includes attachment portions 11da, 11dd, 11dg which are an example of a panel attachment portion fixed to the inner bottom surface 68b of the housing 60. According to this configuration, the panel holder 11d on which the display panel 12 is installed is directly fixed to the inner bottom surface 68b via the attachment portions 11da, 11dd, 11dg. Therefore, displacement of the display panel 12 can be suppressed.

[0050] (4) The display panel 12 includes a rectangular frame portion 12b provided on the outer periphery of the display panel 12. The frame portion 12b includes a wide portion 12b1 that is the upper side among the sides of the frame portion 12b, and a narrow portion 12b2 that is a lower side different from the wide portion 12b1 among the sides of the frame portion 12b and is narrower than the wide portion 12b1. The positioning portions 11d5, 11d6, 11d7 are arranged to contact the wide portion 12b1 of the frame portion 12b. According to this configuration, since the wide portion 12b1 receives the force from the positioning portions 11d5, 11d6, 11d7, stress concentration or deformation of the display panel 12 can be suppressed.

[0051] (5) The head-up display device 100 includes a heat sink 16 which is an example of a heat radiating member that radiates heat from the backlight unit 15. The housing 60 includes a vehicle body attachment portion 68m which is an example of a first vehicle body attachment portion provided on the outside of the housing 60 and formed to be attachable to the vehicle body. The heat sink 16 is formed to be attachable to the vehicle body and includes a vehicle body attachment portion 16b which is an example of a second vehicle body attachment portion that overlaps the first vehicle body attachment portion. According to this configuration, by overlapping the vehicle body attachment portion 16b on the vehicle body attachment portion 68m, the rigidity of the vehicle body attachment portion 68m is increased. Therefore, the head-up display device 100 can be attached to the vehicle body more firmly. Also, a reinforcing rib is not required for the vehicle body attachment portion 68m. For example, as a comparative example, in a configuration where the vehicle body attachment portion of the heat sink is attached to the vehicle body alone, since the two members of the heat sink and the housing are attached to the vehicle body alone, it becomes difficult to attach them stably. In this regard, according to the above configuration, the vehicle body attachment portion 16b of the heat sink 16 only reinforces the vehicle body attachment portion 68m of the housing 60 and is attached to the vehicle body with one member of the housing 60, so the head-up display device 100 can be stably attached to the vehicle body.

[0052] (6) The backlight unit 15 includes a light source 19b that emits light, a condenser lens 18a and lenticular lenses 18b, 18c which are an example of optical members for adjusting the light from the light source 19b, a light guide case 17b that surrounds the periphery of the light source 19b, the condenser lens 18a and the lenticular lenses 18b, 18c, and a lens cover 17a that forms a frame shape along the outer periphery of the condenser lens 18a and the lenticular lenses 18b, 18c and is attached to the light guide case 17b to hold the condenser lens 18a and the lenticular lenses 18b, 18c within the light guide case 17b. The light guide case 17b includes a fixing portion 17c that is fixed to the heat sink 16 through a screw 65d which is an example of fixing means. The fixing portion 17c is provided at a position overlapping the lens cover 17a in the height direction H along the traveling direction of the light emitted by the light source 19b. According to this configuration, since the fixing portion 17c is arranged to overlap the lens cover 17a in the height direction H, the backlight unit 15 can be configured compactly. Also, by configuring the backlight unit 15 compactly, the heat sink 16 can also be configured compactly.

[0053] (7) A screw hole 17d into which the shaft portion of the screw 65d, which is fixing means, is screwed is formed in the fixing portion 17c. A screw through hole 16a2 that is positioned opposite to the screw hole 17d and through which the shaft portion of the screw 65d passes is formed in the heat sink 16. The head-up display device 100 includes a light entry suppression ring 65e that surrounds the outer periphery of the shaft portion of the screw 65d, is positioned to contact the head of the screw 65d, and hides the screw through hole 16a2 from the outside of the heat sink 16. According to this configuration, entry of external light into the head-up display device 100 is suppressed by the light entry suppression ring 65e. Therefore, the display quality of the virtual image V can be improved.

[0054] The display unit 10 includes a display panel 12 that emits display light L upon receiving illumination light from the backlight unit 15, and a cable 12k connected to the panel main body 12a. The display unit 10 further includes a control board 70, which is an example of a control unit that is located on the outer bottom surface 68c side, is connected to the display panel 12 via the cable 12k, and controls the display panel 12, and a cable guide portion 11u2 that extends from the panel main body 12a toward the control board 70 along the cable 12k. A cable through hole 68d through which the cable guide portion 11u2 and the cable 12k pass is formed in the boundary plate portion 68v. According to this configuration, the cable guide portion 11u2 surely guides the cable 12k from the panel main body 12a through the cable through hole 68d to the control board 70. In addition, since the cable guide portion 11u2 is formed so as to cover the cable 12k, stray light is suppressed from reaching the cable 12k.

[0055] (9) The display unit 10 includes a display panel 12 that emits display light L upon receiving illumination light from the backlight unit 15, and a light-transmitting member 14 through which the display light L that has passed through the display panel 12 passes. The light-transmitting member 14 includes a base material 14a, a polarization layer 14b that is formed on the back surface of the base material 14a close to the display panel 12 and polarizes the display light L from linear polarization to circular polarization including elliptical polarization, and a high retardation layer 14c that is formed on the surface of the base material 14a opposite to the back surface. According to this configuration, the high retardation layer 14c cuts off external light such as sunlight and suppresses the display panel 12 from increasing in temperature due to the external light. Further, the polarization layer 14b polarizes the display light L into circular polarization, reduces the polarization of the P wave and the S wave included in the display light L, and can improve the visibility of the virtual image V when wearing polarized glasses such as sunglasses.

[0056] Note that the present disclosure is not limited to the above embodiments and drawings. Modifications (including deletion of components) can be appropriately made without changing the gist of the present disclosure. An example of a modification will be described below.

[0057] (Modification example) The light entry suppression ring 65e in the above embodiment may be omitted. The vehicle body attachment portion 16b in the above embodiment may be provided independently without overlapping the vehicle body attachment portion 68m. Further, the vehicle body attachment portion 16b may be omitted. The cable guide portion 11u2 in the above embodiment may be omitted. The number, position, or shape of the pressing portions 11d2, 11d3, 11d4 in the above embodiment can be changed as appropriate. Similarly, the number, position, or shape of the positioning portions 11d5, 11d6, 11d7 can be changed as appropriate. For example, the roof portions 11dy of the positioning portions 11d5, 11d6 in the above embodiment may be provided independently of the L-shaped columnar portion 11dl, or may be omitted. Further, the two portions of the L-shaped columnar portion 11dl that are orthogonal to each other may be provided at independent and separated positions. The cable 12k in the above embodiment was a flexible flat cable, but it may be a cable other than a flexible flat cable.

[0058] The base material 14a of the light-transmitting member 14 in the above embodiment may be a hot mirror. Further, the light-transmitting member 14 may be omitted.

[0059] In the above embodiment, the tip of the pressing portion 11u5 was in contact with the wide portion 12b1 of the frame portion 12b, but it is not limited to this, and it may be in contact with the narrow portion 12b2 of the frame portion 12b. Further, the tip of the pressing portion 11u5 may be in contact with the side in the short side direction of the frame portion 12b. In the above embodiment, the light-transmitting member 14 and the display panel 12 faced each other at different angles, but it is not limited to this, and the light-transmitting member 14 and the display panel 12 may face each other in parallel. In the above embodiment, each fixing portion 17c was arranged so as to overlap the lens cover 17a in the height direction H of the backlight unit 15, but it is not limited to this, and it may be arranged outside the lens cover 17a. In the above-described embodiment, the panel holder 11d fixes the display panel 12 in an inclined posture on the inner bottom surface 68b of the lower case 68. However, the present invention is not limited to this, and the display panel 12 may be fixed in a posture along the inner bottom surface 68b of the lower case 68.

[0060] In the above-described embodiment, the head-up display device 100 is mounted on the vehicle 5. However, it may be mounted on vehicles other than the vehicle 5, such as airplanes and ships. Further, the projection member is not limited to the windshield 6, and may be a dedicated combiner.

Explanation of Reference Numerals

[0061] 1 Viewer 5 Vehicle 6 Windshield 10 Display unit 11d Panel holder 11d1 Main body frame portion 11d2, 11d3, 11d4 Pressing portion 11d5, 11d6, 11d7 Positioning portion 11d8 Elastic support portion 11d9 Installation convex portion 11da, 11dd, 11dg Mounting portion 11db, 11de, 11di Pin through hole 11dc, 11df, 11dj Screw through hole 11df Mounting hook 11dh Light through hole 11dk Leaf spring portion 11ds Inclined surface 11dt Claw portion 11dl L-shaped columnar portion 11dy Roof portion 11m Middle holder 11m1 Through hole 11u Holder cover 11u1 Main body frame portion 11u2 Cable guide 11u3 Base plate portion 11u4 Inner peripheral side wall portion 11u5 Pressing portion 11u6 Outer peripheral side wall portion 11ur rib 11ut convex part 12 display panel 12a panel main body part 12b frame part 12b1 wide part 12b2 narrow part 12k cable 13 diffusion plate 14 light-transmitting member 14a base material 14b polarizing layer 14c high retardation layer 15 backlight unit 16 heat sink 16a main body container part 16a1 bottom plate 16a2 screw passing hole 16b vehicle body mounting part 16b1 screw through hole 16b2 pin passing hole 17a lens cover 17a1 hook 17a2 frame part 17b light guide case 17b1 convex part 17c fixing part 17d screw hole 18a condenser lens 18b,18c lenticular lens 19a light source substrate 19b light source 19c heat conduction sheet 20 reflector 30 concave mirror 50 window part 60 housing 61 upper case 61h opening 62 middle case 63 second mirror holder 65a,65b,65c,65d screw 65e light entry suppression ring 67 substrate cover 68 lower case 68a light passing hole Inner bottom surface of 68b Outer bottom surface of 68c Cable through-hole of 68d Pins of 68g, 68h, 68i Vehicle body mounting parts of 68j, 68k, 68m Screw through-holes of 68j1, 68k1, 68m1 Positioning pin of 68j2 Fixing parts of 68e, 68f Boundary plate part of 68v First mirror holder of 69 Control board of 70 Connector of 71 Mirror drive unit of 78 Head-up display device of 100 Angles of α, β Height direction of H Display light of L Virtual image of V Optical path space of Sc Rotation axis of Ax

Claims

1. A head-up display device, comprising: a backlight unit that emits illumination light; a display unit that receives the illumination light from the backlight unit and emits display light; a housing that houses the backlight unit and the display unit, wherein the housing includes a boundary plate portion having a light passage hole through which the illumination light travels from the backlight unit toward the display unit; the display unit is provided on a first surface side of the boundary plate portion; the backlight unit is provided on a second surface side of the boundary plate portion, opposite to the first surface side; the display unit includes a display panel that receives the illumination light from the backlight unit and emits the display light; a panel holder on which the display panel is installed; the panel holder includes a positioning portion that contacts a side surface of the display panel; a pressing portion that presses the display panel toward the positioning portion in a plane direction of the display panel; the positioning portion has an L-shaped columnar shape and includes an L-shaped columnar portion that positions the display panel in its plane direction; a roof portion provided at a part of an upper end of the L-shaped columnar portion and that positions the display panel in a direction perpendicular to its plane; the positioning portion and the pressing portion are provided on the same member; a head-up display device.

2. The head-up display device according to claim 1, wherein the panel holder includes a panel attachment portion that is fixed to the first surface of the boundary plate portion. The head-up display device according to claim 1.

3. The head-up display device according to claim 1, wherein the display panel includes a rectangular frame portion provided on an outer periphery of the display panel; the frame portion includes a wide portion that is any one of the sides of the frame portion; a narrow portion that is any one of the sides of the frame portion different from the wide portion and has a width narrower than that of the wide portion; the positioning portion is arranged to contact the wide portion of the frame portion. The head-up display device according to claim 1 or 2.

4. The head-up display device according to claim 1, wherein the head-up display device includes a heat dissipation member that dissipates heat from the backlight unit; the housing includes a first vehicle body attachment portion provided outside the housing and formed to be attachable to a vehicle body; the heat dissipation member is formed to be attachable to the vehicle body and includes a second vehicle body attachment portion that overlaps the first vehicle body attachment portion. The head-up display device according to any one of claims 1 to 3.

5. The head-up display device according to claim 1, wherein the head-up display device includes a heat dissipation member that dissipates heat from the backlight unit. The backlight unit includes: a light source that emits light; an optical member that adjusts the light from the light source; a light guide case that surrounds the periphery of the light source and the optical member; a lens cover that forms a frame shape along the outer periphery of the optical member and is attached to the light guide case to hold the optical member within the light guide case; the light guide case includes a fixing portion that is fixed to the heat dissipation member through fixing means; the fixing portion is provided at a position overlapping the lens cover in the traveling direction of the light emitted by the light source; The head-up display device according to any one of claims 1 to 4.

6. A screw hole into which the shaft portion of the screw, which is the fixing means, is screwed is formed in the fixing portion; a screw passing hole that is formed in the heat dissipation member so as to face the screw hole and through which the shaft portion of the screw passes is formed; The head-up display device includes: a light entry suppression ring that surrounds the outer periphery of the shaft portion of the screw, is positioned to contact the head of the screw, and hides the screw passing hole from the outside of the heat dissipation member; The head-up display device according to claim 5.

7. The display unit includes: a display panel having a panel main body portion that emits the display light by receiving the illumination light from the backlight unit, and a cable connected to the panel main body portion; a control unit that is positioned on the second surface side, is connected to the panel main body portion via the cable, and controls the display panel; a cable guide portion that extends from the panel main body portion toward the control unit along the cable; a cable passing hole through which the cable guide portion and the cable pass is formed in the boundary plate portion; The head-up display device according to any one of claims 1 to 6.

8. The display unit includes: a display panel that emits the display light by receiving the illumination light from the backlight unit; a light-transmitting member through which the display light that has passed through the display panel passes; The light-transmitting member includes: a base material; a polarization layer that is formed on the back surface of the base material close to the display panel and polarizes the display light from the display panel from linear polarization to circular polarization; a high retardation layer that is formed on the surface of the base material opposite to the back surface; The head-up display device according to any one of claims 1 to 7.

Images