WO2021002428A1

WO2021002428A1 - Head-up display device

Info

Publication number: WO2021002428A1
Application number: PCT/JP2020/026005
Authority: WO
Inventors: 誠秦; 俊輔佐治
Original assignee: 日本精機株式会社
Priority date: 2019-07-03
Filing date: 2020-07-02
Publication date: 2021-01-07
Also published as: JPWO2021002428A1

Abstract

The present invention provides a head-up display device having a display region formed along a road surface, and a display region inclined so as to rise from an angle along the road surface while keeping costs low.　A display surface 24 includes a display surface distant region 241 corresponding to a distant virtual image region 151, and a display surface nearby region 243 corresponding to a nearby virtual image region 153. The display surface nearby region 243 is disposed to be inclined with respect to an optical axis 40p of image light 40 traveling to a viewer such that the nearby virtual image region 153 is disposed along the longitudinal direction of a vehicle, and the display surface distant region 241 is disposed to be bent with respect to the display surface nearby region 243 such that the distant virtual image region 151 rises to the viewer side with respect to the nearby virtual image region 153.

Description

Head-up display device

The present disclosure relates to a head-up display device that is used in a vehicle and superimposes an image on the foreground of the vehicle for visual recognition.

Patent Document 1 includes a display that displays a main image facing a occupant of a vehicle, and a projector that displays a sub-image in which one end side is adjacent to the main image and the other end side is located in front of one end side. A head-up display device comprising a screen is disclosed.

Japanese Unexamined Patent Publication No. 2016-71051

In the head-up display device of Patent Document 1, there are two displays, a display for displaying an image facing the driver and a display (projector and screen) arranged along the road surface. Is required, and it is expected that parts costs will rise.

The following is a summary of the specific embodiments disclosed herein. It should be understood that these aspects are presented solely to provide the reader with an overview of these particular embodiments and do not limit the scope of this disclosure. In fact, the present disclosure may include various aspects not described below.

The outline of the present disclosure relates to providing a head-up display device having a display area along the road surface and a display area having an inclination as if rising from an angle along the road surface, while suppressing costs.

Therefore, the head-up display device of the embodiment described in the present specification is a head-up display device that allows a viewer to visually recognize a virtual image in a virtual image display area along the front-rear direction of the vehicle, and the virtual image display area is a distant virtual image. It is composed of a region and a near virtual image region closer to the distant virtual image region when viewed from the viewer, and the display surface in the display is a display surface distant region corresponding to the distant virtual image region and a display surface near the display surface corresponding to the near virtual image region. The region near the display surface, including the region, is arranged at an angle with respect to the optical axis of the image light toward the viewer so that the near virtual image region is arranged along the front-rear direction of the vehicle, and is a region far from the display surface. Is bent with respect to the display surface near region so that the distant virtual image region rises toward the viewer with respect to the near virtual image region (153).

It is a figure which shows the application example to the vehicle of the head-up display device which concerns on some embodiments. It is a figure which shows the structure of the head-up display apparatus which concerns on some embodiments. It is a figure which shows the arrangement of the relay optical system of a comparative example, and a display surface. It is a figure which shows the arrangement of the virtual image display area generated in the comparative example of FIG. 3A. It is a figure which shows the arrangement of a relay optical system and a display surface which concerns on some embodiments. It is a figure which shows the arrangement of the virtual image display area generated in the embodiment of FIG. 4A. It is a figure which shows the relationship between the position in the depth direction (Z-axis direction) of the virtual image display area, and the tilt angle which concerns on some Embodiments. It is a figure which shows the relationship between the position in the depth direction (Z-axis direction) of the virtual image display area, and the tilt angle which concerns on some Embodiments. It is a figure which shows the relationship between the position in the depth direction (Z-axis direction) of the virtual image display area, and the tilt angle which concerns on some Embodiments. It is a figure which shows the arrangement of the virtual image display area which concerns on some embodiments. It is a figure which shows the arrangement of the virtual image display area which concerns on some embodiments. It is a figure which shows the arrangement of the virtual image display area which concerns on some embodiments. It is a figure which shows the arrangement of a relay optical system and a display surface which concerns on some embodiments.

Hereinafter, FIGS. 1 and 2 provide a description of the configuration of an exemplary vehicle display system and head-up display device. Further, FIGS. 3A and 3B provide a description of a comparative example, and FIGS. 4A to 8 provide a description of the configuration of the present embodiment. The present invention is not limited to the following embodiments (including the contents of the drawings). Of course, changes (including deletion of components) can be made to the following embodiments. Further, in the following description, in order to facilitate understanding of the present invention, description of known technical matters will be omitted as appropriate.

Refer to FIG. The vehicle display system 10 includes a HUD device 20 and a display control device 30 that controls the HUD device 20. In the description of the present embodiment, the left-right direction when the viewer (driver 4) seated in the driver's seat of the vehicle 1 faces the front of the vehicle 1 is the X-axis (the left direction is the X-axis positive direction), and the top and bottom. The direction is the Y-axis (the upward direction is the Y-axis positive direction), and the front-rear direction is the Z-axis (the front direction is the Z-axis positive direction).

The HUD device 20 in the vehicle display system 10 is a head-up display (HUD: Head-Up Display) device provided in the dashboard 5 of the vehicle 1. The HUD device 20 emits the image light 40 toward the front windshield 2 (an example of the projected portion), and the image light 40 reflected by the front windshield 2 creates an eyebox (not shown) in a predetermined area. Generate. By arranging the eye point in the eye box, the driver 4 can visually recognize the entire image displayed by the HUD device 20. Here, the eye box is defined as an area where the entire image can be seen, but the present invention is not limited to this, and the area where the distortion of the image displayed by the HUD device 20 visually recognized by the viewer falls within a predetermined threshold value. This is an area where the image displayed by the HUD device 20 is visually recognized in a desired state. The image (virtual image) is visually recognized in the virtual image display area 100 on the front side (Z-axis positive direction) of the front windshield 2 (an example of the projected portion). As a result, the driver 4 can visually recognize the image (virtual image) superimposed on the foreground 300, which is the real space that is visually recognized through the front windshield 2.

The vehicle display system 10 (HUD device 20) of the present embodiment forms the virtual image display area 100 along the road surface 310 (an example of the foreground 300). Specifically, in the imaginary image display area 100 along the road surface 310, the distance 100Z in the depth direction (Z-axis direction) between the far end 110 and the near end 120 of the imaginary image display area 100 is the imaginary image display area 100. It is shown that the distance between the highest position (far end 110 in FIG. 1) and the lowest position (near end 120 in FIG. 1) in the height direction (Y-axis direction) is 20 times or longer than 100Y, and further. Preferably, it indicates that the distance 100Z in the depth direction (Z-axis direction) is 40 times or longer than the distance 100Y in the height direction (Y-axis direction). In the virtual image display area 100 of one embodiment, if it is represented by (Z coordinate [meter], Y coordinate [meter]) and the center in the height direction of the eye box is (0, 1.2), the near end 120 is (14.5, 0.0), the far end 110 (highest position) is (53.4, 1.48), and the far end 110 and the near end 120 when the driver 4 sees from the center of the eyebox. The center of is (27.3, 0.15). In this case, the distance 100Z in the depth direction (Z-axis direction) is 38.9 [meter], and the distance 100Y in the height direction (Y-axis direction) is 1. It becomes 48 [meter], and the distance 100Z in the depth direction (Z-axis direction) is 26 times the distance 100Y in the height direction (Y-axis direction). The virtual image display area 100 is a curved surface or a partially curved surface area where the image generated inside the HUD device 20 is imaged as a virtual image, and is also called an image forming surface. The virtual image display area 100 is a position where a virtual image of the display surface (screen 24) described later of the HUD device 20 is formed, that is, the virtual image display area 100 corresponds to the display surface described later of the HUD device 20 and is a virtual image. It can be said that the virtual image visually recognized in the display area 100 corresponds to the image displayed on the display surface described later of the HUD device 20. It is preferable that the virtual image display area 100 itself has low visibility to the extent that it is not actually visible to the driver 4 or is difficult to see.

FIG. 2 is a diagram showing the configuration of the HUD device 20 of the present embodiment. The HUD device 20 includes a display 21 having a display surface for displaying an image, and a relay optical system 25.

The display 21 of FIG. 2 is composed of a projector 22 (an example of an image generation unit) and a screen 24 (an example of a display surface) that receives projected light from the projector 22 and displays an image (real image). It is a projection type display. The display 21 may be a transmissive display (an example of an image generation unit) that transmits light from a backlight such as an LCD, or a self-luminous display (an example of an image generation unit). .. In these cases, the display surface is a display surface (an example of a display surface) in a transmissive display and a screen 24 (an example of a display surface) of a projection type display. The display surface is from an angle perpendicular to the optical axis 40p of the image light 40 from the display surface toward the eye box (center of the eye box) via the relay optical system 25 and the projected portion described later. It is tilted so that the virtual image display area 100 can be arranged along the road surface 310. An actuator (not shown) such as a motor controlled by the display control device 30 may be attached to the display 21 so that the display surface can be moved and / or rotated.

The display surface 24 of the present embodiment is non-planar and has a boundary (the display surface bent portion IM5 described later) in which the continuity of the flat surface or the curved surface is lost (bent), whereby the far side of the virtual image display area 100 is obtained. The far virtual image region 151 of the above is raised from the near virtual image region 153 on the side closer to the far virtual image region 151 of the virtual image display region 100. This will be described in detail later.

The relay optical system 25 is on the optical path of the light of the image from the display 21 (light from the display 21 toward the eye box) between the display 21 and the front windshield 2 (an example of the projected portion). It is composed of one or more optical members that project the light of the image from the display 21 onto the front windshield 2 outside the HUD device 20. The relay optical system 25 of FIG. 2 includes a first mirror 26 and a second mirror 28.

The first mirror 26 has a concave free curved surface shape in which the radius of curvature is substantially constant from one end to the other end. In other words, the first mirror 26 has a curved surface shape in which the optical power is substantially the same for each region, that is, the optical power applied to the image light 40 is the same according to the region (optical path) through which the image light 40 passes. is there. Specifically, the relay optical system 25 adds the first image light 41, the second image light 42, and the third image light 43 (see FIG. 2) from each region of the display surface toward the eyebox. The optical power is about the same.

The second mirror 28 is a flat mirror, but is not limited to this, and may be a curved surface having optical power instead of a flat surface.

Further, the relay optical system 25 synthesizes a plurality of mirrors having a curved surface shape in which the optical power differs for each region, so that the optical power applied according to the region (optical path) through which the image light 40 passes is substantially the same. As such, the optical power for each region of the plurality of mirrors may be set.

In the present embodiment, the relay optical system 25 includes two mirrors, but the present invention is not limited to this, and one or more refractive optics such as a lens may be added or substituted to these. A member, a diffractive optical member such as a hologram, a reflective optical member, or a combination thereof may be included.

Further, the relay optical system 25 of the present embodiment has a function of setting a distance to a position where a virtual image is formed (virtual image display area 100) by the curved surface shape (an example of optical power), and a screen 24 (an example of an optical power). It has a function to generate an enlarged virtual image of the image displayed on the display surface), but in addition to this, it has a function to suppress (correct) the distortion of the virtual image that may occur due to the curved shape of the front windshield 2. You may be doing it.

Further, the relay optical system 25 may be movable and / or rotatable to which an actuator (not shown) such as a motor controlled by the display control device 30 is attached.

Next, the arrangement of the relay optical system 25 and the non-planar display surface 24 and the arrangement of the generated virtual image display area 100 according to the present embodiment will be described. The virtual image display area 100 of the present embodiment is formed so as to have an inclination on the distant side along the road surface 310.

First, a comparative example will be described with reference to FIGS. 3A and 3B. FIG. 3A is a diagram showing an arrangement of the relay optical system 500 and the display surface 524 of the comparative example. In FIG. 3A, the focal points of the

regions

501, 502, and 503 of the relay optical system 500 are indicated by

reference numerals

501f, 502f, and 503f in order to make the difference from the present embodiment easy to understand. These

focal points

501f, 502f, It does not accurately show the distance relationship between the 503f and the relay optical system 500, and the distance relationship between the

focal points

501f, 502f, 503f and the display surface 524. In the comparative example, the display surface 524 is a flat surface. That is, the display surface 524 of the comparative example does not have the display surface bending portion IM5 described later. Further, as in the embodiment of the present invention described below, the display surface 524 is arranged at an angle α from the vertical surface 524a with the optical axis 540p of the image light directed from the display surface 524 toward the eyebox. Specifically, it is arranged at an angle α from the vertical surface 524a of the optical axis 540p of the image light 540 from the display surface 524 toward the eye box. Specifically, the display surface 524 is farther than the virtual image display neighborhood portion 603 from the region M3 on the display surface 524 corresponding to the virtual image display neighborhood portion 603 (FIG. 3B) of the virtual image display region 600 as compared with the vertical plane 524a. It is arranged so as to gradually move away from the relay optical system 500 toward the region M2 on the display surface 524 corresponding to the region 602 (FIG. 3B) of the virtual image display region 600. In other words, from the area M3 on the display surface 524 corresponding to the virtual image display neighborhood portion 603 of the virtual image display region 600 to the display surface 524 corresponding to the region 602 (FIG. 3B) of the virtual image display region 600 farther from the virtual image display neighborhood portion 603. It is arranged so as to gradually approach the focal point of the relay optical system 500 toward the region M2 (the distance between the region M2 and the focal point 502f is shorter than the distance between the region M3 and the focal point 503f). In such a case, as shown in FIG. 3B, when viewed from the left-right direction (X direction) of the vehicle 1, the cross section of the generated virtual image display area 600 is on the driver 4 side (upper side (Y-axis positive direction)). It becomes convex.

Next, this embodiment will be described with reference to FIGS. 4A and 4B. FIG. 4A is a diagram showing an arrangement of the relay optical system 25 and the display surface 24 of the present embodiment. The display surface 24 of the present embodiment includes a display surface distant region 241 corresponding to the distant virtual image region 151 and a display surface near region 243 corresponding to the near virtual image region 153, and the display surface near region 243 is the display surface 24. The image light 40 is arranged at an angle α from the vertical surface 24a with respect to the optical axis 40p of the image light 40 toward the eye box. Specifically, the display surface 24 displays a virtual image from the display surface proximity portion IM3 of the display surface 24 corresponding to the virtual image display proximity portion 103 included in the near virtual image region 153 of the virtual image display region 100 as compared with the vertical surface 24a. It is arranged so as to gradually move away from the relay optical system 25 toward the display surface bending portion IM5 of the display surface 24 corresponding to the virtual image display bending portion 105 of the region 100. In other words, from the display surface near portion IM3 of the display surface 24 corresponding to the near virtual image region 153 of the virtual image display region 100 toward the display surface bent portion IM5 of the display surface 24 corresponding to the virtual image display bent portion 105 of the virtual image display region 100. The relay optical system 25 is gradually arranged so as to approach the focal point (the distance between the display surface bending portion IM5 and the focal point 255f is made shorter than the distance between the display surface near portion IM3 and the focal point 253f).

Further, the display surface 24 of the present embodiment has a display surface bending portion IM5, and is based on an approximate inclination (dotted line in FIG. 4A) of the display surface 24 from the display surface vicinity portion IM3 to the display surface bending portion IM5. In addition, the display surface 24 is bent so that the approximate inclination of the display surface 24 from the display surface bending portion IM5 to the display surface distant portion IM1 approaches the relay optical system 25. In other words, it is arranged so as to gradually approach the focal point of the relay optical system 25 from the display surface bending portion IM3 toward the display surface bending portion IM5 (the distance between the display surface bending portion IM5 and the focal point 255f is set near the display surface. It is arranged so as to be shorter than the distance between the unit IM3 and the focal point 253f) and gradually approach the focal point of the relay optical system 25 from the display surface bending portion IM5 toward the display surface distant portion IM1 (display surface distant portion IM1). The distance between the focal point 251f and the focal point 251f is made longer than the distance between the display surface bending portion IM5 and the focal point 255f).

Here, between the distance a (> 0) between the object and the concave mirror, the distance b (> 0) between the virtual image and the concave mirror, and the focal length f (> a) of the concave mirror, The following relational expression holds. According to this relational expression, the shorter the distance between the object and the concave mirror, the shorter the distance b of the virtual image.
1 / a-1 / b = 1 / f

As described above, the display surface 24 is arranged so as to be tilted from the optical axis 40p of the image light from the display surface 24 toward the eye box so that the virtual image display area 100 is along the road surface 310 (from the vicinity). It is arranged so that the imaging distance gradually increases toward a distance). The first image light 41 projected from the display surface 24 (display surface distant region 241 (display surface distant portion IM1)) onto the first region 251 of the first mirror 26 is provided by the display surface distant region 241 (display surface distant portion IM1). Since it is close to the first region 251 when reflected by the front windshield 2, the imaging distance from the front windshield 2 is short (compared to the case where the display surface is not bent and cannot be brought close to the relay optical system). Become.

The display surface 24 of the present embodiment has an approximate inclination of the display surface 24 from the display surface near portion IM3 to the display surface bent portion IM5 in the display surface distant region 241 with the display surface bent portion IM5 as a boundary (FIG. 4A). By moving closer to the relay optical system 25 (reducing the distance between the object and the concave mirror) than (dotted line), the far virtual image region 151 (including the far end 110) of the virtual image display region 100 is along the road surface 310. It can be curved so that it rises from the inclination. The fact that the distant virtual image region 151 (including the distant end 110) is curved so as to rise from an inclination along the road surface 310 is a tangent line of the phantom image display region 100 in the distant virtual image region 151 (virtual image display distant portion 101) as shown in FIG. 4B. The tangent line of the virtual image display area 100 in the near virtual image region 153 (central portion 102) where the tilt angle θ (first tilt angle θ1) between the vehicle and the road surface 310 is closer to the driver 4 than the far virtual image region 151 and the road surface 310. It is larger than the tilt angle θ (second tilt angle θ2) between them, and the tilt angle θ continuously increases (monotonically increases) from the central portion 102 (near side) toward the distant virtual image region 151 (far side). To do).

5A to 5C are diagrams showing the relationship between the position of the virtual image display area 100 in the depth direction (Z-axis direction) and the tilt angle θ according to the embodiment. In the present embodiment, the far virtual image region 151 (far end 110) only needs to rise from the inclination along the road surface 310 from the central portion 102 near the far virtual image region 151, and as shown in FIG. 5A, the far end 110 from the near end 120 The tilt angle θ is not limited to monotonically increasing toward.

That is, in some embodiments, as shown in FIG. 5B, the rate of increase (change rate) of the tilt angle θ from the virtual image display near portion 103 to the virtual image display bent portion 105 is far from the virtual image display bent portion 105. It may be made smaller than the rate of increase (rate of change) of the tilt angle θ up to the unit 101. In this case, the display surface 24 allows the display surface bending portion IM5 and the fifth image light 45 to pass from the distance between the display surface vicinity portion IM3 and the third region 253 of the relay optical system 25 through which the third image light 43 passes. The rate of increase up to the distance between the fifth region 255 of the relay optical system 25 is displayed from the distance between the display surface bending portion IM5 and the fifth region 255 of the relay optical system 25 through which the fifth image light 45 passes. It is made smaller than the rate of increase up to the distance between the far-field IM1 and the first region 251 of the relay optical system 25 through which the first image light 41 passes. As a result, it is possible to suppress the change in the distance between the near virtual image region and the road surface as the distance increases in the depth direction.

Further, in some embodiments, as shown in FIG. 5C, the rate of change of the tilt angle θ from the near virtual image region 153 to the central portion 102 is gradually increased from a negative value to zero, and the far end from the central portion 102. The rate of increase (rate of change) of the tilt angle θ up to 110 may be larger than zero. The arrangement of the virtual image display area 100 in this case is shown in FIG. That is, the position of the virtual image display region 100 gradually decreases in the vertical direction (Y-axis direction) from the near virtual image region 153 to the central portion 102, the central portion 102 is the lowest position, and the position gradually decreases from the central portion 102 to the far end 110. The position in the vertical direction (Y-axis direction) becomes higher, and the near end 120 is set as the highest position. In this case, the inclination α of the display surface 24 is made larger than that of the above embodiment, and the display is performed from the distance between the display surface vicinity portion IM3 and the third region 253 of the relay optical system 25 through which the third image light 43 passes. The rate of increase up to the distance between the surface bending portion IM5 and the fifth region 255 of the relay optical system 25 through which the fifth image light 45 passes is shown by the relay optical system 25 through which the surface bending portion IM5 and the fifth image light 45 pass. The rate of increase is made smaller than the rate of increase from the distance between the fifth region 255 and the distance between the remote portion IM1 of the display surface and the first region 251 of the relay optical system 25 through which the first image light 41 passes. As a result, the change in the distance between the virtual image display area on the near side and the road surface can be suppressed to be small as the distance in the depth direction increases.

Further, in some embodiments, a part including the lowest position of the virtual image display area 100 is arranged below the road surface 310, and a part including the far end 110 of the virtual image display area 100 is arranged above the road surface. You may. For example, in the virtual image display area 100, as shown in FIG. 7A, the near end 120 is at the lowest position, and the part from the near end 120 to the far end 110 is arranged under the road surface 310 to the far end 110. The other part may be arranged on the road surface 310. Further, as shown in FIG. 7B, the virtual image display area 100 may have the central portion 102 between the far end 110 and the near end 120 as the lowest position. The discomfort when the virtual image is shifted to the front side with respect to the road surface when viewed from the viewer is greater than the discomfort when the image is shifted to the back side with respect to the road surface. Therefore, even if the angle of the vehicle 1 changes, it is possible to prevent the virtual image display area 100 from being arranged above the road surface 310, and the virtual image display area on the near side becomes the road surface 310 due to the change in the angle of the vehicle 1. Even when it is arranged on the upper side of the above, the distance between the image on the near side and the road surface 310 in the height direction can be suppressed to be small.

Further, in some embodiments, the display surface 24 is arranged so that the virtual image display bending portion 105 of the virtual image display area 100 is arranged at a distance of 20 meters or more in the front direction of the driver 4 (vehicle 1). The position of the display surface bending portion IM5 may be set. According to this, in the virtual image display area 100, the tilt angle θ of the tangent line of the virtual image display area 100 with respect to the front-rear direction of the vehicle 1 becomes monotonous as the vehicle 1 moves toward the far side from a distance of 20 meters or more in the front direction. It increases and rises from an angle along the road surface 310. The inventor of the present invention has recognized that the sense of distance (sense of distance) for an object 20 meters or more away from the viewer becomes dull. That is, even if the distance between the virtual image display area and the road surface is monotonically increased from a position 20 meters or more away from the viewer, it is difficult for the viewer to perceive the difference in distance between the virtual image display surface and the road surface (20 meters). (Easy to perceive as if it is displayed along the road surface like the image displayed in the virtual image display area less than), and the virtual image display area on the distant side is curved so as to rise from an angle along the road surface to the viewer side. By doing so, the virtual image display surface on the distant side seen from the viewer can be overlapped with a wide foreground (for example, a road surface) area. In other words, the area of the overlapping foreground (for example, the road surface) per unit area of the virtual image display area can be expanded, and the images can be efficiently superimposed and displayed on the wide foreground.

In the above embodiment, the first mirror 26 has a free curved surface shape in which the radius of curvature is substantially constant from one end to the other end, but the present invention is not limited to this, and the curvature may not be substantially constant. .. In particular, in the present embodiment, the display surface bent portion IM5 is provided on the display surface 24 so that the inclination of the virtual image display area 100 on the distant side rises from an angle along the road surface. By making the radius of curvature (optical power) different for each region of the mirror 26 (relay optical system 25), the inclination of the virtual image display region 100 on the distant side may be easily raised from an angle along the road surface.

Specifically, the first mirror 26 may have a free curved surface shape in which the radius of curvature gradually changes from one end to the other end. In other words, the first mirror 26 has a curved surface shape in which the optical power differs for each region, that is, even if the optical power applied to the image light 40 differs depending on the region (optical path) through which the image light 40 passes. Good. Specifically, the relay optical system 25 adds the first image light 41, the second image light 42, and the third image light 43 (see FIG. 2) from each region of the display surface toward the eyebox. The optical power is different.

The second mirror 28 may be a curved surface having optical power instead of a flat surface. That is, the relay optical system 25 is added according to the region (optical path) through which the image light 40 passes by synthesizing a plurality of mirrors (for example, the first mirror 26 and the second mirror 28 of the present embodiment). The optical power may be different.

FIG. 8 is a diagram showing the arrangement of the relay optical system 25 and the display surface 24 of the present embodiment. In FIG. 8, the focal points of each region 251,252,253 of the relay optical system 25 are indicated by

reference numerals

251f, 252f, 253f in order to make the difference from the comparative example easy to understand, but the relay optical system 25 or the display It does not accurately show the distance relationship with the surface 24. The relay optical system 25 of FIG. 8 has a different radius of curvature for each region. Specifically, the first optical of the first region (first optical path) 251 of the relay optical system 25 through which the first image light 41 that displays a virtual image in the distant virtual image region 151 of the virtual image display region 100 when viewed from the driver 4 passes. The second region (second region) of the relay optical system 25 through which the second image light 42 that displays a virtual image passes through the virtual image display bending portion 105 that is closer to the distant virtual image region 151 of the virtual image display region 100 when viewed from the driver 4. Optical path) Make it smaller than the second optical power of 252. That is, when the main optical power of the relay optical system 25 is caused by the first mirror 26 which is a concave mirror, the first radius of curvature of the first region 251 reflecting the first image light 41 (an example of the first optical power. ) Is made larger than the second radius of curvature (an example of the second optical power) of the second region 252 that reflects the second image light 42. When the first radius of curvature of the first region 251 that reflects the first image light 41 becomes large, the focal length (1/2 of the radius of curvature) of the focal length 251f of the first region 251 becomes long.

According to the above-mentioned relational expression of "1 / a-1 / b = 1 / f", the larger the radius of curvature of the concave mirror (the smaller the curvature of the mirror), the longer the focal length of the concave mirror, and the longer the focal length. The longer the distance b, the shorter the distance b of the virtual image.

By arranging the display surface 24 at an angle from the optical axis 40p of the image light from the display surface 24 toward the eye box, the virtual image display area 100 is gradually arranged along the road surface 310 (from the vicinity to the distance). (So that the imaging distance becomes longer), it is arranged. The first image light 41 projected from the display surface 24 onto the first region 251 having a large radius of curvature of the first mirror 26 has a long focal length (distance from the first region 251 to the focal length 251f), and therefore is used on the front windshield 2. When reflected, the imaging distance from the front windshield 2 becomes shorter (compared to the case where the radius of curvature is not increased).

In the relay optical system 25 of the present embodiment, the farther the virtual image displayed by the passing image light is, the smaller the optical power is gradually reduced (the radius of curvature is gradually increased), so that the virtual image display region 100 The distant virtual image region 151 (far end 110) of the can be curved so as to rise from an inclination along the road surface 310. Therefore, the display surface 24 is bent so that the distant virtual image region of the virtual image display surface rises from the road surface, and the optical power of the relay optical system 25 is similarly applied to each region so that the distant virtual image region of the virtual image display surface rises from the road surface. By combining the above, it is possible to bend the virtual image display surface more greatly, and it is also possible to improve the design freedom of the display surface 24 and the relay optical system 25.

The display surface distant portion IM1 corresponding to the distant virtual image region 151 and the display surface near portion IM3 corresponding to the near virtual image region 153 are discontinuously coupled. That is, the display surface 24 is formed so that the display surface far portion IM1 is connected to the display surface near portion IM3 not by the smooth curved surface but by the discontinuous display surface bending portion IM5.

1: Vehicle 2: Front windshield 4: Driver 5: Dashboard 10: Vehicle display system 20: HUD device 21: Display 22: Projector 24: Screen (display surface)
25: Relay optical system 26: First mirror 28: Second mirror 30: Display control device 40: Image light 40p: Optical axis 41: First image light 42: Second image light 43: Third image light 45: Fifth Image light 100: Virtual image display area 101: Virtual image display Far part 102: Central part 103: Virtual image display Near part 105: Virtual image display bent part 110: Far end 120: Near end 151: Far virtual image area 153: Near virtual image area 241: Display Surface distant area 243: Display surface vicinity area 251: First area 252: Second area 253: Third area 255: Fifth area 310: Road surface IM1: Display surface distant part IM3: Display surface near part IM5: Display surface bending part α: Angle θ: Tilt angle θ1: First tilt angle θ2: Second tilt angle

Claims

A head-up display device that allows a viewer to visually recognize a virtual image in a virtual image display area along the front-rear direction of the vehicle.
An indicator having a display surface that emits image light that is the source of the virtual image,
A relay optical system configured to relay the image light emitted by the display surface toward the projected portion is provided.
The virtual image display region is composed of a distant virtual image region and a near virtual image region closer to the distant virtual image region when viewed from the viewer.
The display surface is
A display surface distant region corresponding to the distant virtual image region and a display surface near region corresponding to the near virtual image region are included.
The display surface proximity region is arranged at an angle with respect to the optical axis of the image light toward the viewer so that the neighborhood virtual image region is arranged along the front-rear direction of the vehicle.
The display surface distant region is bent and arranged with respect to the display surface near region so that the distant virtual image region rises toward the viewer with respect to the near virtual image region.
Head-up display device.
The display surface distant region is formed so as to be connected to the display surface near region by the discontinuous display surface bending portion.
The display surface bending portion is arranged so that the virtual image display bending portion of the virtual image display surface corresponding to the display surface bending portion is arranged at a distance of 20 meters or more in the front direction of the viewer. The indicator, which is configured as
The head-up display device according to claim 1, further comprising.
The relay optical system so as to prevent the upper side of the near virtual image region from bending convexly caused by the region near the display surface being arranged at an angle with respect to the optical axis of the image light toward the viewer. The indicator, configured such that the side is formed on a concave curved surface.
The head-up display device according to claim 1, further comprising.
Virtual image display in the distant virtual image display region A first region having a first optical power through which a first image light for displaying the virtual image passes in a distant portion, and a first region.
The virtual image display bent portion has a fifth region having a fifth optical power through which a fifth image light for displaying the virtual image passes.
A relay optical system configured such that the first optical power is smaller than the fifth optical power.
The head-up display device according to claim 1, further comprising.
A third region having a third optical power through which the third image light for displaying the virtual image passes in a portion near the virtual image display closer to the bent portion of the virtual image display when viewed from the viewer is further included.
The relay optical system configured such that the rate of change of optical power from the fifth region to the first region is larger than the rate of change of optical power from the third region to the fifth region.
The head-up display device according to claim 4, further comprising.
The first region, the fifth region, and the region between them so that the angle of the tangent line of the virtual image display region with respect to the front-rear direction of the vehicle increases monotonously in a broad sense from the vicinity of the viewer toward the distance. The relay optical system that adjusts the distribution of the optical power,
The head-up display device according to claim 4, further comprising.
The virtual image display bent portion is located between the far end and the near end of the virtual image display area as seen by the viewer in the front-rear direction of the vehicle, and is arranged at the lowest position of the virtual image display area.
The head-up display device according to claim 4.
A part of the virtual image display area is arranged below the road surface, and another part including the virtual image display distant part is arranged above the road surface.
The head-up display device according to claim 4.
In the virtual image display region, a part including the virtual image display bent portion is arranged below the road surface, and another portion including the virtual image display distant portion is arranged above the road surface.
The head-up display device according to claim 8.