Head-up display device

Abstract

In a head-up display device, a transparent cover (23) closes an opening (11) and transmits magnified display light reflected by a mirror (22). The opening part (11) is provided with a folded edge part (F) for shielding light on the side opposite to the eye point (EP) side of the opening part (11). The transparent cover (23) is configured so as to include a curved portion (230) formed in a curved shape. The curved section (230) has: an inner surface section (232) positioned on the mirror (22) side; and an outer surface section (231) that is located on the opposite side from the mirror (22) side and that converges external light on the folded edge section (F). Furthermore, the thickness between the inside surface section (232) and the outside surface section (231) in the third direction (Z) is formed so as to become thicker from the edgefold (F) side toward the eye point (EP) side in a range closer to the eye point (EP) side than the lowest point (Q2) of the transparent cover (23) in the third direction (Z).

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] Technical problem that the invention aims to solve

[0007] However, the head-up display device for a vehicle described in Patent Document 1 described above is intended to suppress, for example, external light reflected by a lens from reaching the eye point 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] Technical solutions to the problem

[0010] In order to solve the above-mentioned problems and achieve the purpose, the head-up display device involved in the present invention comprises: a display unit, which is arranged in a vehicle and displays a virtual image by reflecting the display light emitted toward the reflecting component toward the eye point side using a reflecting component that can transmit light; and a shell, which has an opening portion opposite to the reflecting component and is used for assembling 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 reflecting component via the opening, and the magnified display light is emitted from the display. light is amplified; and a transparent cover, which closes the above-mentioned opening and allows the above-mentioned amplified display light reflected by the above-mentioned reflector to pass through, the above-mentioned opening is provided with a folded edge portion for shielding light on the side of the opening opposite to the above-mentioned eye point side, the above-mentioned transparent cover is constructed to include a curved portion formed in a curved shape, the above-mentioned curved portion has: a first surface portion located on the above-mentioned reflector side, and a second surface portion located on the side opposite to the above-mentioned reflector side and focusing external light on the above-mentioned folded edge portion, the vertical thickness between the above-mentioned first surface portion and the above-mentioned second surface portion is formed to become thicker from the above-mentioned folded edge portion side toward the above-mentioned eye point side within a range closer to the above-mentioned eye point side than the lowest point of the above-mentioned vertical direction of the above-mentioned transparent cover.

[0011] Effects of the Invention

[0012] The head-up display device of the present invention can focus the external light reflected by the second face portion on the folded edge portion. In addition, the head-up display device is formed so that the thickness of the transparent cover becomes thicker from the folded edge portion side toward the eye point side, so that the reflectivity of the external light reflected by the first face portion and the second face portion can be relatively reduced. As a result, the head-up display device can make the brightness of the external light reflected inside the transparent cover relatively small, so even if the external light reflected inside the transparent cover reaches the eye point, it can be suppressed that the external light is visually recognized as a double image. As a result, the head-up display device can appropriately display a virtual image. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 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 the relationship between the reflection of external light and the eyellipse according to the embodiment.

[0016] Figure 4 It is a schematic diagram showing an example of reflection of external light in a comparative example.

[0017] Figure 5 It is a schematic diagram showing an example of reflection of external light in the embodiment. DETAILED DESCRIPTION

[0018] 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. In addition, the structures described below can be appropriately combined. In addition, various omissions, substitutions or changes of the structure can be made within the scope of the gist of the present invention.

[0019] [Example]

[0020] 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 the display light L1 emitted toward the windshield WS that can transmit light to be reflected toward the eye point EP side at the windshield WS, 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, and is provided in front of the driver's seat to block the wind. The head-up display device 1 can be an AR-HUD device that superimposes and displays the virtual image S on an object in front of the vehicle (for example, a person, a sign, another vehicle, etc.), and can also be a HUD device that displays the virtual image S without corresponding the virtual image S to the object in front of the vehicle. The head-up display device 1 is described in detail below.

[0021] 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 referred to as the direction along the straight direction of the vehicle. The third direction Z can also be referred to as the 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 referred to as the directions along the horizontal plane orthogonal to the vertical direction.

[0022] like Figure 1 As shown, the head-up display device 1 includes a housing 10 and a display unit 20 .

[0023] 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 accommodated inside the housing 10. The housing 10 has an opening 11 that connects the inside with the outside. The opening 11 is a portion that is provided opposite to the windshield WS and can transmit light.

[0024] The display unit 20 reflects the display light L1 emitted toward the windshield WS toward the eye point EP side at the windshield WS to display the virtual image S. The display unit 20 includes a display 21 , a reflective mirror 22 , and a transparent cover 23 .

[0025] The display 21 emits display light L1 including 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 forms an image, and is configured, for example, by a TFT-LCD (Thin Film Transistor-Liquid Crystal Display). The backlight irradiates light to the back of the display unit, and is configured, for example, by a plurality of LEDs (light-emitting diodes). The display 21 irradiates light to the display unit through the backlight, thereby emitting display light L1 including 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.

[0026] In addition, in this example, the display 21 is partially accommodated in 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 in the housing 10, and the portion other than the emitting portion of the display 21 (for example, the backlight source) is exposed to the outside of the housing 10.

[0027] The reflector 22 is a component that totally reflects light and is accommodated inside the housing 10. The reflector 22 has a reflective surface 221 that is formed into a concave shape and is aspherical. The reflective surface 221 is arranged opposite to the display 21 and is arranged opposite to the transparent cover 23. The reflector 22 amplifies the display light L1 (image) emitted from the display 21 by the reflective surface 221, and reflects the amplified display light L2 toward the windshield WS via the opening 11 (transparent cover 23) of the housing 10. Specifically, the reflector 22 amplifies the display light L1 that is directly emitted from the display 21 without passing through other reflectors by the reflective surface 221, and reflects the amplified display light L2 toward the windshield WS via the opening 11 (transparent cover 23) of the housing 10.

[0028] 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 formed to be curved toward the inside of the housing 2. That is, the curved portion 230 is formed to be concave toward the inside of the housing 2. Figure 2As 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.

[0029] The outer surface portion 231 is located on the side opposite to the reflector 22 side, and is a surface formed by bending toward the inside of the housing 2. That is, the outer surface portion 231 is a surface provided on the windshield WS side. The outer surface portion 231 reflects external light toward the folded edge portion F. Here, the folded edge portion F is a light shielding component, and is provided upright on the side of the opening 11 opposite to the eye point EP side. That is, the folded edge portion F is a wall portion extending along the third direction Z on the side opposite to the eye point EP side of the transparent cover 23. In this example, the folded edge 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 folded edge portion F. Specifically, the XZ cross section of the outer surface portion 231 cut along the first direction X and the third direction Z is not curved, but is formed in a straight line. In addition, the YZ cross section of the outer surface portion 231 cut along the second direction Y and the third direction Z is formed in a curved shape, and the curvature is formed in a curved shape that can reflect external light toward the folded edge portion F. The outer surface portion 231 reflects external light incident from the outside of the housing 2 toward the hem portion F. For example, Figure 3 As shown, the outer surface portion 231 reflects the external light P1a and P1b that travels toward the windshield WS from the upper end side of the eyellip EL in the third direction Z and is reflected by the windshield WS toward the transparent cover 23 side, toward the folded edge portion F. In addition, the outer surface portion 231 reflects the external light P2a and P2b that travels toward the windshield WS from the lower end side of the eyellip EL in the third direction Z and is reflected by the windshield WS toward the transparent cover 23 side, toward the folded edge portion F. The eyellip EL is a predetermined spatial region, and is a region pre-conceived as a region where the positions of the driver's eyes are distributed.

[0030] The inner side surface portion 232 is located on the side of the reflector 22 and is a face portion formed in a curved manner toward the inside of the housing 2. That is, the inner side surface portion 232 is a face portion provided on the side opposite to the windshield WS side. The inner side surface portion 232 has a free curved surface 232a. 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 into a shape that corrects the aberration of the virtual image S generated by optical components including the windshield WS, etc. The free curved surface 232a is, for example, formed into 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 enlarged display light L2 reflected by the reflector 22 through the free curved surface 232a. The transparent cover 23 emits the corrected magnified display light L2 having undergone aberration correction by the free curved surface 232a toward the windshield WS. The corrected magnified display light L2 emitted toward the windshield WS is reflected toward the eye point EP by the windshield WS and guided to the eye point EP.

[0031] Here, if Figure 4 As shown, the transparent cover 90 of the comparative example is formed such that the thickness in the third direction Z between the inner side surface 92 and the outer side surface 91 becomes thinner from the folded edge F side toward the eye point EP side within the range closer to the eye point EP side than the lowest point Q1 in the third direction Z of the transparent cover 90. Therefore, for the transparent cover 90 of the comparative example, when the external light P3 is incident on the transparent cover 90 and propagates inside the transparent cover 90, the incident angle of the external light P3 becomes relatively large. Therefore, the reflectivity of the transparent cover 90 to the external light P3 becomes large, thereby making it easy to be reflected multiple times and propagate, so that the external light P3 is easy to travel in the direction of the reflector 22. Therefore, in the comparative example, there is a tendency that after the external light P3 is reflected inside the transparent cover 90, it is transmitted through the transparent cover 90 toward the reflector 22 and reflected at a position toward the opening 11 on the upper end side of the reflector 22 in the third direction Z. Therefore, in the comparative example, there is a problem that the external light P3 is guided to the eye point EP after being reflected inside the transparent cover 23, and a double image is generated due to the external light P3.

[0032] In contrast, Figure 5 As shown, the transparent cover 23 of the embodiment is formed so that the thickness D (see FIG. 1 ) in the third direction Z between the inner side surface 232 and the outer side surface 231 is within the range closer to the eye point EP than the lowest point Q2 in the third direction Z of the transparent cover 23. Figure 2) becomes thicker from the folded edge F side toward the eye point EP side. That is, the transparent cover 23 is formed so that, in the YZ cross section cut along the second direction Y and the third direction Z, within the range closer to the eye point EP side than the lowest point Q2 of the transparent cover 23, the interval in the third direction Z between the inner side surface 232 and the outer side surface 231 gradually widens from the folded edge F side toward the eye point EP side. In addition, in this example, the lowest point Q2 of the transparent cover 23 in the third direction Z enters the lower side of the folded edge F in the third direction Z. That is, the lowest point Q2 of the transparent cover 23 overlaps with the folded edge F when viewed from the third direction Z.

[0033] According to this structure, Figure 5 As shown, in the head-up display device 1 according to the embodiment, when the external light P4 enters the transparent cover 23 and propagates inside the transparent cover 23, the incident angle of the external light P4 is smaller than that in the comparative example. Therefore, the reflectivity of the external light P4 of the head-up display device 1 becomes smaller, thereby becoming difficult to propagate, and therefore, the external light P4 is difficult to travel in the direction of the reflector 22. In addition, in the head-up display device 1, since the incident angle of the external light P4 is small, the external light P4 that passes through the transparent cover 23 and is emitted toward the reflector 22 has a tendency to be reflected toward a position different from the position of the opening 11 (for example, the display 21 side) at the lower end side of the reflector 22 in the third direction Z. As a result, the head-up display device 1 can suppress the external light P4 from being guided to the eye point EP after being reflected inside the transparent cover 23, and can suppress the occurrence of double images caused by the external light P4. In addition, the head-up display device 1 also considers a case where the external light P4 is reflected inside the transparent cover 23, then passes through the transparent cover 23, is emitted toward the reflector 22, and is reflected toward the opening 11 on the upper end side of the reflector 22 in the third direction Z. In this case, the head-up display device 1 can relatively reduce the brightness of the external light P4 because the external light P4 is reflected on the inner surface portion 232 and the outer surface portion 231 at a lower reflectivity than the external light P3 of the comparative example, thereby suppressing the occurrence of double images caused by the external light P4 even when the external light P4 is guided to the eye point EP.

[0034] 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 toward the eye point EP side at the windshield WS. The housing 10 has an opening 11 facing the windshield WS, and the display unit 20 is assembled. The display unit 20 is configured to include: a display 21, a reflector 22, and a transparent cover 23. The display 21 is accommodated in the housing 10, and emits the display light L1. The reflector 22 is accommodated in 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 opening 11 is provided with a folded edge F that shields light on the side opposite to the eye point EP side of the opening 11. The transparent cover 23 is configured to include a curved portion 230 formed in a curved shape. The curved portion 230 includes an inner side surface portion 232 located on the reflector 22 side and an outer side surface portion 231 located on the side opposite to the reflector 22 side and focusing external light on the folded edge portion F. The thickness D between the inner side surface portion 232 and the outer side surface portion 231 in the third direction Z is formed to become thicker from the folded edge portion F side toward the eye point EP side within a range closer to the eye point EP side than the lowest point Q2 in the third direction Z of the transparent cover 23.

[0035] With this structure, the head-up display device 1 can focus the external light reflected by the outer surface portion 231 on the folded edge portion F. In addition, the head-up display device 1 is formed so that the thickness D of the transparent cover 23 becomes thicker from the folded edge portion F side toward the eye point EP side, so that the reflectivity of the external light reflected by the inner surface portion 232 and the outer surface portion 231 can be relatively reduced. As a result, the head-up display device 1 can make the brightness of the external light P4 reflected inside the transparent cover 23 relatively small, so even if the external light P4 reflected inside the transparent cover 23 reaches the eye point EP, it is possible to suppress the external light P4 from being visually recognized as a double image. As a result, the head-up display device 1 can appropriately display the virtual image S.

[0036] In the head-up display device 1, the inner side surface 232 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 performs task allocation by making the transparent cover 23 mainly responsible for the aberration correction function and the reflector 22 mainly responsible for the magnification function, 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 allocation, so it can be easily manufactured, thereby reducing tolerance. The head-up display device 1 can suppress the increase in the number of components and suppress the enlargement of the optical system by making the transparent cover 23 that closes the opening 11 of the housing 10 also have the function of aberration correction. As a result, the head-up display device 1 can appropriately display the virtual image S.

[0037] 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 amplified display light L2 obtained by amplifying 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 the device can be miniaturized.

[0038] [Variation]

[0039] Next, a modification of the embodiment is described. In addition, in the modification, the same reference numerals are given to the components equivalent to those of the embodiment, and their detailed description is omitted. The reflector 22 may also be configured to reflect the external light P4 emitted toward the reflector 22 after being reflected by the inner side surface 232 and the outer side surface 231 of the transparent cover 23 and passing through the transparent cover 23 to a position different from the position of the opening 11. In this case, even if it is assumed that the external light P4 cannot be reflected by the reflector 22 to a position different from the position of the opening 11, but the external light P4 is reflected toward the opening 11 by the reflector 22, the brightness of the external light P4 can be made relatively small as described above, so that even if the external light P4 reaches the eye point EP, it is possible to suppress the external light P4 from being visually recognized as a double image. The head-up display device 1 can further suppress the external light P4 from being visually recognized as a double image by configuring the reflector 22 in a manner that reflects the external light P4 to a position different from the position of the opening 11.

[0040] In the above description, an example is described in which the display 21 directly emits the display light L1 to the reflector 22 without passing through other reflectors. However, the present invention is not limited to this, and the display light L1 may be indirectly emitted to the reflector 22 via other reflectors.

[0041] In the above description, the free curved surface 232 a is formed on the reflector 22 side of the transparent cover 23 , 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.

[0042] 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 relative to the magnification of the reflector 22.

[0043] The reflector 22 may have a function of correcting the aberration of the virtual image S in addition to the function of amplifying the display light L1 (image) by the reflective surface 221. In this case, the reflector 22 corrects the aberration of the virtual image S with a smaller aberration correction amount than the transparent cover 23. For example, the reflector 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.

[0044] In the above description, an example is described in which the reflecting member is the windshield WS, but the present invention is not limited to this, and for example, a combiner or the like may also be used.

[0045] The outer surface portion 231 and the inner surface portion 232 of the transparent cover 23 may also be in the shape of a Fresnel lens.

[0046] Explanation of symbols

[0047] 10 Housing

[0048] 11 Opening

[0049] 20 Display units

[0050] 21 Display

[0051] 22 Reflector

[0052] 23 Transparent cover

[0053] 230 Bend

[0054] 231 Lateral face (second face)

[0055] 232 medial face (first face)

[0056] 232a Free-form surface

[0057] EP Eye Spot

[0058] F Folding part

[0059] L1 Display light

[0060] L2 Amplified display light

[0061] P4 External light

[0062] S virtual image

[0063] WS windshield (reflective parts)

[0064] DThickness

[0065] Z third direction (vertical direction)

[0066] Q2 Lowest Point

Claims

1. A head-up display device, characterized in that: have: a display unit provided in the vehicle and displaying a virtual image by reflecting display light emitted toward the reflective member toward an eye point side using a reflective member capable of transmitting light; as well as a housing having an opening facing the reflective member and for assembling the display unit, The display unit is configured to include: a display, the display being received in the housing and emitting the display light; a reflector, the reflector being housed inside the housing and reflecting the 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; and a transparent cover that closes the opening and transmits the magnified display light reflected by the reflector, The opening has a folded edge portion erected on the side of the opening opposite to the eye point side for shielding light. The transparent cover is configured to include a curved portion formed in a curved shape. The bent portion includes a first surface portion located on the reflector side and a second surface portion located on the side opposite to the reflector side and focusing external light on the folded edge portion. The thickness between the first surface portion and the second surface portion in the vertical direction is formed so as to become thicker from the folded edge portion side toward the eye point side within a range closer to the eye point side than the lowest point of the transparent cover in the vertical direction.

2. The head-up display device according to claim 1, wherein: The reflector reflects external light, which is reflected by the first surface portion and the second surface portion of the transparent cover and then passes through the transparent cover and is emitted toward the reflector, to a position different from the position of the opening.

3. The head-up display device according to claim 1 or 2, wherein: The first surface portion has a free-form surface that corrects aberration of the enlarged display light reflected by the reflection mirror.

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

Images