Head-up display device

Abstract

In a head-up display device (1), a transparent cover (23) has an inner surface section (232) positioned on the side of a mirror (22) and an outer surface section (231) positioned on the opposite side from the side of the mirror (22). The display light (L1) guided to the eye point (EP) includes: normal light (L1a) which is guided to the eye point (EP) through the transparent cover (23) without being reflected by an inner surface portion (232) and an outer surface portion (231) of the transparent cover (23); and irregular light (L1b) that is reflected by the inner surface section (232) and the outer surface section (231) of the transparent cover (23) and then is guided to the eye point (EP) through the transparent cover (23). An inner surface section (232) of the transparent cover (23) has an incidence surface (232b) that causes an incidence angle at which the irregular light (L1b) is incident to be 65 DEG or less.

Description

Technical Field

[0001] The invention relates to a head-up display device. Background Art

[0002] Conventionally, as a head-up display device, a head-up display for a vehicle that displays a virtual image through a front windshield of a vehicle is described in, for example, Patent Document 1. The head-up display for a vehicle includes: a housing that is disposed on a dashboard of a vehicle and has an opening that emits image light of an image; a display that is accommodated in the housing and emits image light of an image; a magnifying glass that is accommodated in the housing and magnifies and reflects an image that is directly incident from the display; and a lens that closes the opening of the housing and magnifies the image that is incident from the magnifying glass and outputs it to the front windshield.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2006-91104 Summary of the invention

[0006] Problems to be solved by the invention

[0007] However, the vehicle head-up display device described in Patent Document 1 may be visually recognized as a double image because, for example, light propagating inside a lens is guided to the eye points of an occupant.

[0008] Therefore, the present invention has been made in view of the above circumstances, and an object of the present invention is to provide a head-up display device capable of appropriately displaying a virtual image.

[0009] Means used to solve problems

[0010] In order to solve the above-mentioned problems and achieve the purpose, the head-up display device involved in the present invention is characterized in that it has: a display unit, which is arranged in a vehicle and uses a light-transmitting reflective component to reflect display light emitted toward the reflective component toward the eye point side, thereby displaying a virtual image; and a shell, which has an opening portion opposite to the reflective component and is assembled with the display unit, and the display unit is constructed to include: a display, which is accommodated in the interior of the shell and emits the display light; a reflector, which is accommodated in the interior of the shell and reflects the magnified display light toward the reflective component via the opening, and the magnified display light is obtained by magnifying the display light emitted from the display ; and a transparent cover, the transparent cover closes the opening and transmits the amplified display light reflected by the reflector, the transparent cover having: a first surface located on one side of the reflector; and a second surface located on a side opposite to the reflector, the display light directed to the eye point includes: regular light, the regular light is directed to the eye point by passing through the transparent cover without being reflected by the first surface and the second surface of the transparent cover; and irregular light, the irregular light is directed to the eye point by passing through the transparent cover after being reflected by the first surface and the second surface of the transparent cover, the first surface of the transparent cover having an incident surface, the incident surface makes the incident angle of the irregular light be less than 65°.

[0011] Effects of the Invention

[0012] The head-up display device according to the present invention can make the brightness of the irregular light directed to the eye point smaller than the brightness of the regular light, thereby preventing the occupant from visually recognizing a virtual image formed by the irregular light. As a result, the head-up display device can prevent the virtual image formed by the irregular light from being visually recognized as a double image, and as a result, can appropriately display the virtual image formed by the regular light. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 1 is a schematic diagram showing a configuration example of a head-up display device according to an embodiment.

[0014] Figure 2 It is a perspective view showing a configuration example of a transparent cover according to an embodiment.

[0015] Figure 3 Schematic diagram showing regular light and irregular light in the embodiment. DETAILED DESCRIPTION

[0016] The mode (embodiment) for implementing the present invention is described in detail with reference to the accompanying drawings. The present invention is not limited to the contents described in the following embodiments. In addition, the constituent elements described below include elements that can be easily thought of by those skilled in the art, and substantially the same elements. Furthermore, the structures described below can be appropriately combined. In addition, various omissions, substitutions or changes in the structure can be made within the scope of the gist of the present invention.

[0017] [Example]

[0018] The head-up display device 1 of the embodiment is described with reference to the accompanying drawings. The head-up display device 1 is provided in a vehicle, and causes display light L1 emitted toward a windshield WS that can transmit light to be reflected on the windshield WS toward the eye point EP side, thereby displaying a virtual image S. Here, the windshield WS is an example of a reflective component, which is a component formed of transparent glass in a plate shape, is provided in front of the driver's seat, and blocks the wind. The head-up display device 1 can be an AR-HUD device that overlaps the virtual image S with an object in front of the vehicle (for example, a person, a sign, another vehicle, etc.) and displays it in an overlapping manner, and can also be a HUD device that displays the virtual image S without overlapping the virtual image S with the object in front of the vehicle. The head-up display device 1 is described in detail below.

[0019] Here, the direction along the vehicle width direction of the vehicle is referred to as the first direction X, the direction along the full length direction of the vehicle is referred to as the second direction Y, and the direction along the up-down direction of the vehicle is referred to as the third direction Z. The second direction Y can also be said to be a direction along the straight direction of the vehicle. The third direction Z can also be said to be a direction along the vertical direction. The first direction X, the second direction Y, and the third direction Z intersect with each other, and are typically orthogonal to each other. In addition, the first direction X and the second direction Y can also be said to be directions along a horizontal plane orthogonal to the vertical direction.

[0020] like Figure 1 As shown, the head-up display device 1 includes a housing 10 and a display unit 20 .

[0021] The housing 10 is provided in the vehicle and is used to assemble the display unit 20. The housing 10 is formed in a box shape, and a display 21 and a reflector 22 of the display unit 20 described later are housed inside the housing 10. The housing 10 has an opening 11 that communicates the inside with the outside. The opening 11 is provided opposite to the windshield WS and is a portion that allows light to pass through.

[0022] The display unit 20 reflects the display light L1 emitted toward the windshield WS toward the eye point EP side of the windshield WS, thereby displaying a virtual image S. The display unit 20 includes a display 21 , a reflective mirror 22 , and a transparent cover 23 .

[0023] The display 21 is a component that emits display light L1 containing an image, and is accommodated inside the housing 10. The display 21 is configured to include a display unit and a backlight, for example. The display unit is a component that forms an image, and is composed of, for example, a TFT-LCD (Thin Film Transistor-Liquid Crystal Display). The backlight irradiates light to the back of the display unit, and is composed of, for example, a plurality of LEDs (light-emitting diodes). The display 21 irradiates light to the display unit through the backlight, thereby emitting display light L1 containing an image from the display unit toward the reflector 22. The display 21, for example, emits the display light L1 directly to the reflector 22 without passing through other reflectors. That is, there is no optical component between the display 21 and the reflector 22.

[0024] In addition, in the display 21 of this example, a part of the display 21 is accommodated inside the housing 10, and the other part of the display 21 is exposed to the outside of the housing 10. Specifically, the emitting portion (for example, the display portion) of the display 21 that emits the display light L1 is accommodated inside the housing 10, and the portion other than the emitting portion of the display 21 (for example, the backlight) is exposed to the outside of the housing 10.

[0025] The reflector 22 totally reflects light and is accommodated inside the housing 10. The reflector 22 has a reflective surface 221 formed in a concave shape and aspherical. The reflective surface 221 is arranged opposite to the display 21 and opposite to the transparent cover 23. The reflector 22 amplifies the display light L1 (image) emitted from the display 21 through the reflective surface 221, and reflects the amplified display light L2 toward the windshield WS through the opening 11 (transparent cover 23) of the housing 10. Specifically, the reflector 22 amplifies the display light L1 directly emitted from the display 21 without passing through other reflectors through the reflective surface 221, and reflects the amplified display light L2 toward the windshield WS through the opening 11 (transparent cover 23) of the housing 10.

[0026] The transparent cover 23 is a cover that closes the opening 11 of the housing 10 and allows light to pass through. The transparent cover 23 is formed of a transparent resin in a curved plate shape and closes the opening 11. The transparent cover 23 has a curved portion 230 that is curved toward the inside of the housing 2. That is, the curved portion 230 is formed in a concave shape toward the inside of the housing 2. Figure 2 As shown, the curved portion 230 has an outer side surface portion 231 as a second side surface portion and an inner side surface portion 232 as a first side surface portion.

[0027] The outer surface portion 231 is located on the side opposite to the reflector 22 side, and is a surface portion formed by bending toward the inside of the housing 2. That is, the outer surface portion 231 is a surface portion provided on the windshield WS side. The outer surface portion 231 reflects external light toward the hem portion F. Here, the hem portion F is a light shielding member, and is provided upright on the side opposite to the eye point EP side of the opening 11. That is, the hem portion F is a wall portion extending along the third direction Z on the opposite side of the eye point EP side of the transparent cover 23. In this example, the hem portion F is provided slightly inclined toward the transparent cover 23 side. The outer surface portion 231 is formed in a shape that reflects external light incident from the outside of the housing 2 toward the hem portion F. For example, in order to cope with external light, the shape of the outer surface portion 231 is bent in the same direction as the inner surface portion 232. That is, the shape of the outer surface portion 231 is bent along the shape of the inner surface portion 232. Specifically, the XZ cross section of the outer surface portion 231 cut along the first direction X and the third direction Z is not bent but formed in a straight line. The outer surface 231 has a curved cross section along the second direction Y and the third direction Z so as to reflect external light toward the hem F. The outer surface 231 reflects external light incident from outside the housing 2 toward the hem F.

[0028] The inner side surface portion 232 is located on the reflector 22 side and is a surface portion that is curved toward the inside of the housing 2. That is, the inner side surface portion 232 is a surface portion that is provided on the opposite side to the windshield WS side. Figure 3 As shown, the inner side surface 232 has an incident surface 232b for the magnified display light L2 reflected by the reflector 22 to be incident. A free-curved surface 232a is formed on the incident surface 232b. The free-curved surface 232a is a curved surface that cannot be expressed by a simple mathematical formula like a sphere, a cylinder, etc. The free-curved surface 232a is, for example, a curved surface that is expressed by setting a plurality of intersections and curvatures in space and interpolating each intersection by a high-order polynomial. The free-curved surface 232a is formed in a shape that corrects the aberration of the virtual image S generated by the optical components including the windshield WS, etc. The free-curved surface 232a is, for example, formed in a shape that corrects the aberration of the virtual image S generated by the shape of the windshield WS. The transparent cover 23 corrects the aberration of the magnified display light L2 reflected by the reflector 22 through the free-curved surface 232a. Then, the transparent cover 23 emits the corrected magnified display light L2, which has been aberration-corrected by the free-curved surface 232a, toward the windshield WS. The corrected enlarged display light L2 emitted toward the windshield WS is reflected toward the eye point EP side by the windshield WS and guided to the eye point EP.

[0029] Here, if Figure 1As shown, the display 21 irradiates light to the display unit (e.g., TFT-LCD) through the backlight, thereby emitting display light L1 including an image from the display unit to the reflector 22. At this time, the display 21 emits light (light rays) radially from each pixel (dot) of the liquid crystal constituting the display unit. Figure 3 As shown, the display light L1 guided to the eye point EP sometimes includes regular light L1a and irregular light L1b different from the regular light L1a. Here, the regular light L1a is light that is not reflected by the inner side surface 232 and the outer side surface 231 of the transparent cover 23 and is guided to the eye point EP through the transparent cover 23. That is, the regular light L1a is light that is not reflected inside the transparent cover 23 and is guided to the eye point EP. The irregular light L1b is light emitted from the same pixel (dot) of the liquid crystal as the regular light L1a, and is light that is reflected by the inner side surface 232 and the outer side surface 231 of the transparent cover 23 and is guided to the eye point EP through the transparent cover 23. That is, the irregular light L1b is light that is emitted from the same pixel (dot) of the liquid crystal as the regular light L1a and is guided to the eye point EP after being reflected inside the transparent cover 23.

[0030] Conventionally, since the irregular light L1b is guided to the eye point EP with substantially the same brightness as the regular light L1a, the virtual image S formed by the irregular light L1b is also visually recognized at the same time as the virtual image S formed by the regular light L1a, and thus the virtual image S is visually recognized as a double image.

[0031] In contrast, the inner side surface 232 of the transparent cover 23 of the embodiment has an incident surface 232b at which the incident angle θ of the irregular light L1b is made 65° or less. That is, the inner side surface 232 of the transparent cover 23 is set so that the incident angle θ of the irregular light L1b on the incident surface 232b is 65° or less. In addition, the outer side surface 231 of the transparent cover 23 is curved along the shape of the inner side surface 232, so that the incident angle of the irregular light L1b incident on the incident surface of the outer side surface 231 is substantially the same as the incident angle θ of the inner side surface 232. The incident angle θ is an angle relative to the normal line N. Here, when the head-up display device 1 sets the incident angle θ to 65° or less, the reflectivity of the irregular light L1b reflected inside the transparent cover 23 can be relatively reduced, and as a result, the brightness of the irregular light L1b can be made 2% or less relative to the brightness of the regular light L1a. Thus, in the head-up display device 1, since the brightness of the irregular light L1b is 2% or less relative to the brightness of the regular light L1a, even when the irregular light L1b is guided to the eye point EP, it is possible to suppress the visual recognition of the virtual image formed by the irregular light L1b. In addition, when the head-up display device 1 sets the brightness of the irregular light L1b to 2% or less relative to the brightness of the regular light L1a, the material of the transparent cover 23, the reflectivity of the inner side surface 232 and the outer side surface 231, etc. are also taken into consideration.

[0032] As described above, the head-up display device 1 of the embodiment includes a display unit 20 and a housing 10. The display unit 20 is provided in a vehicle, and displays a virtual image S by reflecting the display light L1 emitted toward the windshield WS that can transmit light on the windshield WS toward the eye point EP side. The housing 10 has an opening 11 facing the windshield WS, and is assembled with the display unit 20. The display unit 20 is configured to include a display 21, a reflector 22, and a transparent cover 23. The display 21 is accommodated inside the housing 10 and emits the display light L1. The reflector 22 is accommodated inside the housing 10, and reflects the enlarged display light L2 obtained by enlarging the display light L1 emitted from the display 21 toward the windshield WS through the opening 11. The transparent cover 23 closes the opening 11, and transmits the enlarged display light L2 reflected by the reflector 22. The transparent cover 23 includes an inner side surface 232 located on the reflector 22 side and an outer side surface 231 located on the side opposite to the reflector 22 side. Here, the display light L1 guided to the eye point EP includes: the regular light L1a, which is not reflected by the inner side surface portion 232 and the outer side surface portion 231 of the transparent cover 23 and passes through the transparent cover 23 to be guided to the eye point EP; and the irregular light L1b, which is reflected by the inner side surface portion 232 and the outer side surface portion 231 of the transparent cover 23 and passes through the transparent cover 23 to be guided to the eye point EP. The inner side surface portion 232 of the transparent cover 23 has an incident surface 232b that makes the incident angle θ of the incident irregular light L1b less than 65°. In other words, the inner side surface portion 232 of the transparent cover 23 has an incident surface 232b that makes the irregular light L1b incident at an angle that makes the brightness of the irregular light L1b less than 2% relative to the brightness of the regular light L1a.

[0033] According to this configuration, the head-up display device 1 can make the brightness of the irregular light L1b guided to the eye point EP lower than the brightness of the regular light L1a, and thus can suppress the passenger from visually recognizing the virtual image S formed by the irregular light L1b. Thus, the head-up display device 1 can suppress the virtual image formed by the irregular light L1b from being visually recognized as a double image, and as a result, can appropriately display the virtual image S formed by the regular light L1a.

[0034] In the head-up display device 1, the incident surface 232b is formed with a free-form surface 232a for performing aberration correction on the magnified display light L2 reflected by the reflector 22. According to this structure, the head-up display device 1 can correct the aberration of the virtual image S generated by optical components including the windshield WS, etc., through the free-form surface 232a of the transparent cover 23. In addition, the head-up display device 1 makes the transparent cover 23 mainly responsible for the aberration correction function and the reflector 22 mainly responsible for the magnification function to perform task distribution, thereby improving the accuracy of aberration correction and improving the magnification ratio. The head-up display device 1 can reduce parameter coefficients by performing task sharing, so it can be easily manufactured, thereby reducing tolerance. In the head-up display device 1, the transparent cover 23 that closes the opening 11 of the housing 10 also has the function of aberration correction, thereby suppressing the increase in the number of components and suppressing the enlargement of the optical system. As a result, the head-up display device 1 can appropriately display the virtual image S.

[0035] In the head-up display device 1, the display 21 directly emits the display light L1 toward the reflector 22. The reflector 22 reflects the enlarged display light L2 obtained by enlarging the display light L1 directly emitted from the display 21 toward the windshield WS via the transparent cover 23. According to this structure, in the head-up display device 1, the display 21 directly emits the display light L1 toward the reflector 22 without passing through other reflectors, so that the device can be miniaturized.

[0036] In the above description, an example is described in which the incident surface 232 b is formed with the free-form curved surface 232 a for aberration correction. However, the present invention is not limited to this, and the free-form curved surface 232 a for aberration correction may not be formed.

[0037] Although the example in which the display 21 directly emits the display light L1 toward the reflector 22 without passing through other reflectors has been described, the present invention is not limited thereto, and the display light L1 may be indirectly emitted toward the reflector 22 via other reflectors.

[0038] In the above description, the free curved surface 232 a is formed on the reflector 22 side of the transparent cover 23 , that is, on the inner side surface portion 232 , but the present invention is not limited thereto and the free curved surface 232 a may be formed on the side of the transparent cover 23 opposite to the reflector 22 side.

[0039] The transparent cover 23 may have a function of amplifying the enlarged display light L2 (image) in addition to the function of correcting the aberration of the virtual image S by the free curved surface 232a. In this case, the transparent cover 23 amplifies the enlarged display light L2 (image) at a magnification smaller than that of the reflector 22. For example, the transparent cover 23 amplifies the enlarged display light L2 (image) at a magnification of about 1 / 10 of the magnification of the reflector 22.

[0040] The reflective mirror 22 may have a function of correcting the aberration of the virtual image S in addition to the function of magnifying the display light L1 (image) by the reflective surface 221. In this case, the reflective mirror 22 corrects the aberration of the virtual image S with a smaller aberration correction amount than the transparent cover 23. For example, the reflective mirror 22 corrects the aberration of the virtual image S with an aberration correction amount of about 1 / 10 of the aberration correction amount of the transparent cover 23.

[0041] In the above description, an example in which the reflecting member is the windshield WS is described, but the present invention is not limited to this, and for example, a synthesizer or the like may also be used.

[0042] Description of Reference Numerals

[0043] 10 Housing

[0044] 11 Opening

[0045] 20 Display units

[0046] 21 Display

[0047] 22 Reflector

[0048] 23 Transparent cover

[0049] 231 Lateral face (second face)

[0050] 232 medial face (first face)

[0051] 232a Free-form surface

[0052] 232b Incident surface

[0053] EP Eye Spot

[0054] L1 Display light

[0055] L2 Amplified display light

[0056] L1a Normal light

[0057] L1b irregular light

[0058] S virtual image

[0059] WS windshield (reflective parts)

Claims

1. A head-up display device, characterized in that: have: A display unit, the display unit being provided in the vehicle and reflecting display light emitted toward the reflective member toward an eye point side by using a light-transmitting reflective member, thereby displaying a virtual image; as well as a housing having an opening facing the reflective member and in which the display unit is assembled, The display unit is configured to include: a display, the display being housed inside the housing and emitting the display light; a reflector, the reflector being housed inside the housing and reflecting amplified display light toward the reflective member via the opening, the amplified display light being obtained by amplifying the display light emitted from the display; as well as a transparent cover that closes the opening and transmits the amplified display light reflected by the reflector, The transparent cover has: a first surface located on one side of the reflector; and a second surface located on a side opposite to the reflector. The display light directed to the eye point includes: regular light, the regular light is transmitted through the transparent cover without being reflected by the first surface and the second surface of the transparent cover, and is directed to the eye point; and irregular light, the irregular light being guided to the eye point through the transparent cover after being reflected by the first face portion and the second face portion of the transparent cover, The first surface portion of the transparent cover has an incident surface that allows the irregular light to be incident at an angle of 65° or less.

2. The head-up display device according to claim 1, characterized in that: The incident surface is formed with a free-form surface, and the free-form surface corrects the aberration of the magnified display light reflected by the reflecting mirror.

3. The head-up display device according to claim 1 or 2, characterized in that: The display directly emits the display light toward the reflector, The reflector reflects the amplified display light toward the reflective member via the transparent cover, and the amplified display light is obtained by amplifying the display light directly emitted from the display.

Images