Head-up display device

Abstract

Provided is a head-up display (HUD) device that can preferably suppress the reflection of an unnecessary image. The HUD device comprises a display unit for emitting display light, a reflection unit for reflecting the display light toward the windshield of a vehicle, a housing for accommodating the display unit and the reflection unit, and a cover unit 50. The housing has a passing port that passes, toward the windshield, the display light reflected from the reflection unit, and a light-shielding unit adjacent to the passing port. The cover unit 50 covers the light-shielding part and has light-blocking properties. The cover unit 50 has a plate part 52 disposed at a distance from the light-shielding unit, and the plate part 52 has a plurality of holes 52a formed therein. Preferably, the plate part 52 is provided with blades 5 extending in a band shape. The plurality of blades 5 are disposed side by side in the transverse direction thereof. The holes 52a are positioned between the mutually adjacent blades 50 and extend along the blades 5.

Description

[Technical field]

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

[0002] 2. Description of the Related Art A head-up display (HUD) device is known that emits display light representing an image onto a windshield of a vehicle and displays a virtual image of the image.

[0003] For example, Patent Document 1 describes a HUD device that includes a housing having a passage opening for passing display light toward the windshield and a light-shielding section adjacent to the passage opening. The HUD device described in Patent Document 1 prevents the image of the light-shielding section from being reflected in the virtual image by attaching a low-reflection sheet that suppresses the reflection of sunlight to the light-shielding section. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2017-3897 A Summary of the Invention [Problem to be solved by the invention]

[0005] Simply providing a low-reflection sheet in the light-shielding portion may not be enough to sufficiently suppress the reflection of unwanted images, and there is still room for improvement.

[0006] The present disclosure has been made in consideration of the above-described circumstances, and has an object to provide a head-up display device that can effectively suppress the reflection of unwanted images. [Means for solving the problem]

[0007] In order to achieve the above object, a head-up display device according to the present disclosure includes: A display unit that emits display light representing an image; a reflecting portion that reflects the display light toward a windshield of a vehicle; a housing that includes a passage opening through which the display light reflected by the reflecting portion passes toward the windshield and a light blocking portion adjacent to the passage opening, and that accommodates the display portion and the reflecting portion; A cover portion that covers the light-shielding portion and has a light-shielding property, The cover portion has a plate portion disposed at a distance from the light blocking portion, The plate portion has a plurality of holes formed therein. Effect of the Invention

[0008] According to the present disclosure, unwanted reflection of images can be effectively suppressed. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic configuration diagram of a head-up display (HUD) device according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a schematic perspective view of the HUD device according to the embodiment. [Diagram 3] FIG. [Figure 4] 3 is a diagram showing a cross section of the covering portion taken along line AA in FIG. 2 and a cross section of the light blocking portion according to the embodiment of the present invention, for explaining the function of the covering portion. FIG. [Diagram 5] 4A to 4C are diagrams for explaining the function of the cover part according to the embodiment; [Figure 6] 4A to 4C are diagrams for explaining the function of the cover part according to the embodiment; [Figure 7] 10A to 10C are diagrams for explaining the function of a cover portion according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] An embodiment of the present disclosure will be described with reference to the drawings.

[0011] A head-up display (HUD) device 100 according to this embodiment is provided in a dashboard (also called an instrument panel) of a vehicle, and emits display light 2 representing an image onto a windshield 1, and displays a virtual image of the image, as shown in Fig. 1. The virtual image is displayed in front of the vehicle through the windshield 1.

[0012] In the following, each configuration may be described using the left-right, up-down, and front-rear directions of the vehicle. In appropriate drawings, an X-axis along the left-right direction, a Y-axis along the up-down direction, and a Z-axis along the front-rear direction are shown.

[0013] As shown in FIG. 1, the HUD device 100 includes a display unit 10, a first mirror 21, a second mirror 22, a housing 30, a control board 40, and a cover unit 50.

[0014] The display unit 10 displays an image and emits display light 2 representing the image toward the first mirror 21. The display unit 10 has, for example, an LCD (Liquid Crystal Display) and a backlight that illuminates the LCD from behind. The LCD is, for example, a TFT (Thin Film Transistor) type. The backlight is, for example, composed of an LED (Light Emitting Diode), a light guide member, etc.

[0015] The first mirror 21 is, for example, a concave mirror, and reflects the display light 2 from the display unit 10 toward the second mirror 22. The second mirror 22 is, for example, a concave mirror, and reflects the display light 2 from the first mirror 21 toward the windshield 1 located outside the HUD device 100. The second mirror 22 is rotated about a rotation axis 22a by a drive mechanism (not shown).

[0016] The first mirror 21 has a curvature such that the focal point 21a of the first mirror 21 is located between the first mirror 21 and the second mirror 22. As a result, the light rays of the display light 2 reflected by the first mirror 21 cross each other above and below before reaching the second mirror 22. An optical system using the first mirror 21 and the second mirror 22 in such a relationship is hereinafter referred to as a cross optical system.

[0017] The housing 30 houses the display unit 10, the first mirror 21, the second mirror 22, etc., and includes a lower case 31, a middle case 32, and an upper case 33.

[0018] The lower case 31 is box-shaped and opens upward, and is made of metal or resin. The lower case 31 covers the middle case 32 from below, and houses the display unit 10 and the control board 40 inside. The lower case 31 is fixed to the middle case 32 by known fixing means such as screws.

[0019] The middle case 32 is box-shaped and opens upward, and is made of metal or resin. The middle case 32 houses the second mirror 22 and a drive mechanism (not shown) inside. An opening H1 is formed at the rear bottom of the middle case 32, through which the display light 2 from the display unit 10 to the first mirror 21 passes.

[0020] The upper case 33 covers the middle case 32 from above, and is fixed to the middle case 32 by known fixing means such as screws. The upper case 33 is formed in a frame shape as shown in Fig. 2. The upper case 33 supports, for example, the first mirror 21. The upper case 33 is formed from, for example, a black resin, and has light-blocking properties.

[0021] The upper case 33 has a passage opening H2 through which the display light 2 reflected by the second mirror 22 passes toward the windshield 1, and a light blocking portion 330 adjacent to the passage opening H2.

[0022] As shown in FIG. 2, the light shielding portion 330 includes a main wall portion 331, side walls 332 and 333, and a front wall portion 334. As shown in FIG. 1, the main wall portion 331 faces the windshield 1 and prevents external light 3, such as sunlight, from entering the housing 30. The main wall portion 331 is inclined, and the front end portion is located lower than the rear end portion. As shown in FIG. 1, the front wall portion 334 generally faces the main wall portion 331 in the front-rear direction. The front wall portion 334 stands along the up-down direction. The side wall portion 332 and the side wall portion 333 face each other in the left-right direction and connect the main wall portion 331 and the front wall portion 334. The passage opening H2 is surrounded by the main wall portion 331, the side walls 332 and 333, and the front wall portion 334, and is generally rectangular as shown in FIG. 2. A part of the edge of the passage opening H2 runs along the lower end of the main wall portion 331. In this embodiment, the main wall portion 331 is provided with a cover portion 50, as described later.

[0023] A cover glass (not shown) is provided at the upper end of the upper case 33. The cover glass covers the passage hole H2, the light blocking portion 330, and the cover portion 50 from above.

[0024] The control board 40 is a printed circuit board equipped with a microcomputer that controls the overall operation of the HUD device 100. The control board 40 controls the display position of the virtual image in the vertical direction by controlling a drive mechanism (not shown) and rotating the second mirror 22. The control board 40 also communicates with systems such as an ECU (Electronic Control Unit) that controls each part of the vehicle, and causes the display unit 10 to display an image showing information related to the vehicle.

[0025] 1 covers the light-shielding portion 330 from the windshield 1 side (i.e., covers the surface of the light-shielding portion 330 facing the windshield 1), and is configured to suppress the image of the light-shielding portion 330 from being reflected in the virtual image. The cover 50 is attached to the main wall portion 331 of the light-shielding portion 330 with elastic double-sided tape T. The cover 50 is provided along the surface of the main wall portion 331 facing the windshield 1, and is inclined like the main wall portion 331, with the front end positioned lower than the rear end. The cover 50 is formed from a material having light-shielding properties.

[0026] In FIG. 2, the cover portion 50 is partially shown for ease of viewing, but the cover portion 50 according to this embodiment is provided over the region 4 of the main wall portion 331, which is indicated by the dashed line.

[0027] 3, the cover portion 50 includes a fixed portion 51 and a plate portion 52. The cover portion 50 is formed from a metal plate having a matte coating applied to the entire surface thereof. For example, the cover portion 50 is produced by forming a thin plate (having a thickness of, for example, 1 mm or less) made of SECC (electro-galvanized steel plate) and then applying a black matte coating.

[0028] The fixed portion 51 is the outer edge of the cover portion 50, and is a portion that is fixed to the main wall portion 331 of the light shielding portion 330. In other words, the fixed portion 51 is a portion to which the above-mentioned double-sided tape T (see FIG. 1) is attached.

[0029] The plate portion 52 is disposed at a distance from the main wall portion 331 of the light-shielding portion 330, and is located, for example, inside the fixed portion 51. In this embodiment, the lower surfaces (surfaces facing the main wall portion 331) of the plate portion 52 and the fixed portion 51 are flush with each other, and the thickness of the double-sided tape T ensures a distance between the plate portion 52 (specifically, the opposing portion 5a described below) and the main wall portion 331. This distance can prevent the plate portion 52 and the main wall portion 331 from rubbing against each other and becoming worn due to vibrations of the vehicle. In addition, the double-sided tape T that ensures this distance can absorb the tolerances of each part by its elasticity and ensure cushioning properties.

[0030] As shown in Fig. 3, the plate portion 52 is formed in a louver shape and includes a plurality of strip-like extending slats 5 and a plurality of holes 52a. The slats 5 extend along the left-right direction (X direction) of the vehicle and are arranged side by side in the short side direction. The holes 52a are located between adjacent slats 5 and are elongated holes extending along the slats 5. For example, the slats 5 are arranged at equal intervals in the short side direction. Therefore, the holes 52a located between adjacent slats 5 are also arranged at equal intervals in the short side direction.

[0031] 4, the blade 5 includes a facing portion 5a facing the main wall portion 331 of the light-shielding portion 330 with a gap therebetween, and an inclined portion 5b connected to the facing portion 5a. The inclined portion 5b is connected to one end of the facing portion 5a (specifically, the end closer to the second mirror 22 shown in FIG. 1) and is inclined so as to move away from the main wall portion 331.

[0032] Here, among the external light 3 (see FIG. 1) that has passed through the windshield 1 and entered the housing 30, the light reflected by the second mirror 22 may head toward the main wall portion 331 of the light-shielding portion 330. In this case, if no measures are taken, the light reflected by the main wall portion 331 of the light-shielding portion 330 will be further reflected by the windshield 1 toward the viewer of the virtual image, causing an unwanted image to be reflected in the virtual image. To suppress this, the cover portion 50 is formed to have the following functions.

[0033] 4 to 6, for ease of explanation, of adjacent blades 5, the one farther from second mirror 22 (see FIG. 1) is referred to as first blade 5f, and the one closer to second mirror 22 is referred to as second blade 5n. Of the external light 3 (see FIG. 1) that passes through windshield 1 and enters housing 30, the light that is reflected by second mirror 22 and heads toward main wall portion 331 of light-shielding portion 330 mainly follows the optical path indicated by light 3a, 3b, and 3c, which will be described below in order.

[0034] As shown in FIG. 4, the inclined portion 5b of the first blade 5f blocks light 3a that passes through a hole 52a between the first blade 5f and the second blade 5n, is reflected by the light-shielding portion 330, and travels toward the windshield 1 (see FIG. 1).

[0035] As shown in FIG. 5, the inclined portion 5b of the first blade 5f is reflected by the opposing portion 5a of the second blade 5n, and blocks the light 3b traveling toward the windshield 1.

[0036] As shown in Figure 6, after being reflected by the inclined portion 5b of the first blade 5f, the light 3c passes through the hole 52a between the first blade 5f and the second blade 5n and is reflected by the shading portion 330, thereby blocking the light 3c traveling toward the windshield 1.

[0037] As described above, the covering portion 50 has the inclined portion 5b that blocks each of the lights 3a, 3b, and 3c. Most of the external light that reaches the covering portion 50 or the main wall portion 331 through optical paths other than the lights 3a, 3b, and 3c heads outside the eye box that is set as a range in which the user can view a virtual image. In other words, the covering portion 50 can reduce the external light 3 that is reflected by the covering portion 50 or the light-shielding portion 330 (specifically, the main wall portion 331) and further reflected by the windshield 1 and then heads toward the inside of the eye box. Therefore, the reflection of unnecessary images can be effectively suppressed.

[0038] Various conditions such as the inclination of the inclined portion 5b in the covering portion 50 and the arrangement interval of the blades 5 and the holes 52a can be obtained by simulation. In particular, since external light reflected at the upper end of the second mirror 22 and directed toward the main wall portion 331 of the light-shielding portion 330 is likely to cause unwanted images to be reflected, it is preferable to perform a simulation taking this into consideration. Also, it is preferable that the range in which the fixed portion 51 in the covering portion 50 is formed is narrow.

[0039] The above-described covering portion 50 is formed, for example, by cutting the portion corresponding to the end of the inclined portion 5b from a single metal plate by laser processing, and then bending the inclined portion 5b. As a result, the shape of the metal plate after molding becomes a louver shape in which the blades 5 and the holes 52a are arranged alternately. The covering portion 50 is produced by applying a matte paint to the entire surface of the metal plate molded into a louver shape.

[0040] The present disclosure is not limited to the above-described embodiments and drawings. Modifications (including the deletion of components) can be made as appropriate within the scope of the present disclosure.

[0041] For example, like a covering portion 50M according to a modified example shown in Fig. 7, the inclined portion 5b may be omitted from the blade 5. By adjusting the distance between the facing portion 5a and the light shielding portion 330, the first blade 5f can block a portion of the light 3a that passes through the hole 52a between the first blade 5f and the second blade 5n, is reflected by the light shielding portion 330, and travels toward the windshield 1 (see Fig. 1). In this case, the hole 52a is not limited to an elongated hole extending in the left-right direction of the vehicle, and may be a round hole.

[0042] In the above, an example in which the cover portion 50 is provided only on the main wall portion 331 of the light-shielding portion 330 has been shown, but the present invention is not limited to this, and the location of the cover portion 50 in the light-shielding portion 330 can be changed as desired. For example, the cover portion 50 may be provided on the side wall portions 332, 333 or the front wall portion 334. In this case, the extending direction of the blades 5 and the holes 52a is set to a direction that can effectively block reflection of external light, and is not limited to the left-right direction of the vehicle, and may be the front-rear direction of the vehicle, etc. From the viewpoint of effectively suppressing reflection of unnecessary images, it is preferable that the cover portion 50 is provided at least on the main wall portion 331.

[0043] The optical system in the HUD device 100 may be configured as desired as long as it can radiate the display light 2 from the display unit 10 to the windshield 1, and the number, shape, and arrangement of the mirrors that reflect the display light 2 may be changed as appropriate. However, as described in the above embodiment, the covering unit 50 is particularly suitable when a cross optical system is adopted. This is because, in a cross optical system, the light irradiated to the main wall portion 331 of the light blocking portion 330 tends to be stronger.

[0044] Although the display unit 10 using an LCD has been described above, the configuration of the display unit 10 is not limited and is arbitrary. For example, the display unit 10 may use an OLED (Organic Light-Emitting Diode). The display unit 10 may also include a DMD (Digital Micromirror Device) and a transmissive screen that receives light reflected by the DMD and displays an image.

[0045] The type of vehicle on which the HUD device 100 is mounted is not limited, and the HUD device 100 can be applied to various vehicles such as four-wheeled motor vehicles and motorcycles.

[0046] The HUD device 100 described above includes a display unit 10 that emits display light 2, a reflector (corresponding to the second mirror 22) that reflects the display light 2 toward the windshield 1, a housing 30 that houses the display unit 10 and the reflector, and covers 50, 50M. The housing 30 has a passage opening H2 through which the display light 2 reflected by the reflector passes toward the windshield 1, and a light-shielding unit 330 adjacent to the passage opening H2. The covers 50, 50M cover the light-shielding unit 330 from the windshield 1 side and have light-shielding properties. The covers 50, 50M include a plate portion 52 that is spaced apart from the light-shielding unit 330, and the plate portion 52 has a plurality of holes 52a formed therein. With this configuration, a part of the external light that passes through the hole 52a and is reflected by the light shielding portion 330 can be blocked by the rear surface (the surface on the light shielding portion 330 side) of the plate portion 52. Therefore, it is possible to effectively suppress the reflection of unnecessary images.

[0047] The plate portion 52 of the cover portion 50 in the embodiment has a strip-like extending blade 5, with multiple blades 5 arranged side by side in the short direction, and the holes 52a are located between adjacent blades 5 and extend along the blades 5. This configuration effectively blocks external light that passes through the hole 52a, is reflected by the light-shielding portion 330, and travels toward the windshield 1. When the cover portion 50 is provided on the main wall portion 331 of the light-shielding portion 330, the blades 5 and the holes 52a are set to extend in the left-right direction of the vehicle, as described above.

[0048] Moreover, it is preferable that the blade 5 has a facing portion 5a that faces the light-shielding portion 330 with a gap therebetween, and an inclined portion 5b that is connected to an end of the facing portion 5a that is closer to the reflecting portion and inclined so as to move away from the light-shielding portion 330. As described with reference to Figs. 4 to 6, the inclined portion 5b is shaped to block at least one of the lights 3a, 3b, and 3c, and preferably to block all of the lights 3a, 3b, and 3c.

[0049] Moreover, the plate portion 52 is made of a metal plate that has been given a matte finish, and the inclined portion 5b is formed by a portion where the blade 5 is bent. This configuration makes it easy to manufacture the cover 50. In addition, since the plate portion 52 of the cover 50 can be made thin, it is also possible to reduce light reflection at the tip surface of the inclined portion 5b, for example. In addition, by using a metal, heat resistance can be ensured.

[0050] In addition, when the requirement for heat resistance is not high (for example, when a cross optical system is not adopted), the covering portion 50 can be molded from a resin. When using a resin, the reflection of light on the surface of the covering portion 50 can be reduced by a known method other than matte painting. In addition, the plate portion 52 of the covering portion 50 can be formed from a metal, and the fixed portion 51 can be formed from a resin. In addition, the covering portion 50 can be fixed to the light shielding portion 330 via an elastic member, a spacer, or the like other than the double-sided tape T, and the interval between the plate portion 52 and the light shielding portion 330 can be secured. In addition, the fixed portion 51 itself can function as a spacer, and the interval between the plate portion 52 and the light shielding portion 330 can be secured.

[0051] In the above description, descriptions of well-known technical matters have been omitted as appropriate in order to facilitate understanding of the present disclosure. [Explanation of symbols]

[0052] 100 Head-up display (HUD) device 1 Windshield 2 display light 3. External Light 4 areas 10 Display 21 Mirror No. 1 22 Second mirror (an example of a reflecting part) 30 Case 33 Upper case H2 passage port 330 Shading section 331 Main wall 332,333 Side wall 334 Front wall 40 Control Board 50 Cover 51 Fixed part 52 Board part 52a hole 5 panel 5a Opposite part 5b Inclined section 5f 1st wing 5n Second board

Claims

1. A display unit that emits display light representing an image; a reflecting portion that reflects the display light toward a windshield of a vehicle; a housing that includes a passage opening through which the display light reflected by the reflecting portion passes toward the windshield and a light blocking portion adjacent to the passage opening, and that accommodates the display portion and the reflecting portion; A cover portion that covers the light-shielding portion and has a light-shielding property, The cover portion has a plate portion disposed at a distance from the light blocking portion, A plurality of holes are formed in the plate portion. Head-up display device.

2. The plate portion includes a blade extending in a band shape, The blades are arranged in a plurality of rows in the short side direction, The holes are located between adjacent blades and extend along the blades. The head-up display device according to claim 1 .

3. The blade is an opposing portion opposed to the light-shielding portion with a gap therebetween; an inclined portion connected to an end of the facing portion close to the reflecting portion and inclined away from the light blocking portion; The head-up display device according to claim 2 .

4. Among the adjacent blades, the one farther from the reflecting portion is designated as a first blade, and the one closer to the reflecting portion is designated as a second blade. The inclined portion of the first blade passes through the hole between the first blade and the second blade, is reflected by the light-shielding portion, and blocks light traveling toward the windshield. The head-up display device according to claim 3 .

5. The inclined portion of the first blade is reflected by the opposing portion of the second blade to block light traveling toward the windshield. The head-up display device according to claim 4.

6. The inclined portion of the first blade reflects the light toward the windshield, passes through the hole between the first blade and the second blade, and is reflected by the light-shielding portion, thereby blocking the light. The head-up display device according to claim 4 or 5.

7. The plate portion is made of a metal plate with a matte coating, The inclined portion is formed by bending the blade. The head-up display device according to any one of claims 3 to 6.

Images