JP2016173583A - Projection device and head-up display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a projection device that is compact and inexpensive, has good light efficiency, and is capable of displaying a display image having a plurality of display distances.SOLUTION: A display unit 21 emits rays of projection light L which display display images M at predetermined positions. An image formation position adjustment mirror 23 receives the rays of projection light L emitted from the display unit 21, changes an image formation distance of at least a part of the incident rays of projection light L to be converted into a plurality of rays of first projection light L1 and second projection light L2 having different image formation distances and reflects the converted rays of the projection light. These first projection light L1 and second projection light L2 are made to form an image on a first screen 30 and a second screen 40 as a real image.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a projection device that projects an image on a predetermined location, and a head-up display device that projects an image projected by the projection device on a reflection / transmission surface and visually recognizes the image together with a landscape.

  A conventional head-up display device is disclosed in Patent Document 1, for example. Such a head-up display device is composed of first and second display devices and a half mirror. By projecting transmitted light and reflected light in duplicate by the half mirror, it is possible to display different display distances to the user. An image (virtual image) is visually recognized.

Japanese Patent Laid-Open No. 2003-237712

  However, since the head-up display device described in Patent Document 1 is provided with a plurality of displays, the capacity of the head-up display device may increase or the cost may increase. Moreover, since the half mirror is used, there is a possibility that the utilization efficiency of the display light emitted from the display device may be reduced.

  Therefore, the present invention has been made in view of this problem, and provides a projection device and a head-up display device capable of displaying a display image having a plurality of display distances that are compact, inexpensive, and light-efficient. is there.

In order to solve the above problem, a projection apparatus according to the first aspect of the present invention provides:
A display that emits projection light for displaying a display image at a predetermined position;
An imaging position adjusting mirror that receives the projection light emitted from the display and reflects the incident projection light by changing an imaging distance of at least a part of the projection light; and
The projection light reflected by the imaging position adjusting mirror is formed as a real image at a position where the distance from the display is different.

The head-up display device according to the second aspect of the present invention is
In a head-up display device that projects a display image on a projection surface and visually recognizes the display image as a virtual image,
A projection unit for emitting projection light;
The projection light emitted from the projection unit is received, converted into a plurality of projection lights having different imaging distances by changing the imaging distance of at least some of the incident projection light, and reflected. An imaging position adjustment mirror;
A second screen that forms projection light having a long imaging distance as a real image among the projection light;
A first screen that is disposed at a position farther from the projection surface than the second screen and forms projection light having a short imaging distance as a real image out of the projection light.

  It is possible to provide a projection device and a head-up display device that can display a display image having a plurality of display distances that are compact, inexpensive, and light-efficient.

Schematic which shows embodiment of this invention. The figure which shows the structure of the 1st screen and 2nd screen of embodiment same as the above. Schematic which shows the modification of this invention. The figure which shows the modification of the imaging position adjustment mirror of this invention.

  Hereinafter, an embodiment of a head-up display device (hereinafter referred to as a HUD device) 100 and a projection device 20 according to the present invention will be described with reference to the accompanying drawings.

  The HUD device 100 is mounted on, for example, an automobile. As shown in FIG. 1, the housing 10, the projection device 20, the first screen (first imaging unit) 30, and the second screen (first A second image forming unit) 40, a plane mirror (relay optical system) 50, a concave mirror (relay optical system) 60, and a control board (not shown). The HUD device 100 uses a plane mirror 50 and a concave mirror 60 to display a first display image M1 projected on the first screen 30 by the projection device 20 and a second display image M2 projected on the second screen 40 by the projection device 20. By reflecting toward the windshield 200 of the vehicle, the first virtual image V1 of the first display image M1 and the second virtual image V2 of the second display image M2 are displayed to the user E.

The housing 10 is made of, for example, black light-shielding synthetic resin, and houses the projection device 20, the first screen 30, the second screen 40, the plane mirror 50, and the concave mirror 60 inside, and a control board (not shown) outside. It is attached.
The housing 10 has an opening 10a that allows display light N to be described later to pass through the windshield 200. The opening 10a is covered with a translucent cover 10b.

  The projection device 20 directs the first projection light L1 indicating the first display image M1 described later and the second projection light L2 indicating the second display image M2 toward the first screen 30 and the second screen 40 described later. The first display image M1 and the second display image M2 are formed on the first screen 30 and the second screen 40. The detailed configuration of the projection device 20 will be described in detail later.

  The first screen (first imaging unit) 30 is a transmissive screen that receives the first projection light L1 emitted from the projection device 20 on the back surface and displays the first display image M1 on the front surface side. Consists of a graphic diffuser, a microlens array, a diffusion plate, and the like. When the first screen 30 displays the first display image M1, the first display light N1 indicating the first display image M1 is projected onto the windshield 200 by the plane mirror 50 and the concave mirror 60 described later, and the user E is projected by the windshield 200. Is reflected in the direction (eye box). Thereby, the user E can visually recognize the 1st virtual image V1 on the other side of the windshield 200. FIG. In the present embodiment, as shown in FIG. 2, the first screen 30 has a concave display area provided with a cutout portion 30a obtained by cutting out a part of a substantially rectangular outer edge portion into a rectangular shape. Therefore, the first virtual image V1 also has a concave display area. In addition, the 2nd projection light L2 mentioned later reaches | attains the 2nd screen 40 mentioned later through the notch part 30a of the 1st screen 30, as shown in FIG.

  The second screen (second imaging unit) 40 is formed in a rectangular shape that is substantially similar to the cutout portion 30a of the first screen 30, and receives the second projection light L2 emitted from the projection device 20 on the back surface. The transmissive screen displays the second display image M2 on the surface side, and is configured by, for example, a holographic diffuser, a microlens array, a diffusion plate, and the like, similar to the first screen 30. When the second screen 40 displays the second display image M2, the second display light N2 indicating the second display image M2 is projected onto the windshield 200 by the plane mirror 50 and the concave mirror 60, which will be described later, and viewed from the user E. The second virtual image V2 is displayed on the other side of the glass 200.

  As shown in FIG. 1, the first screen 30 is disposed closer to the projection device 20 than the second screen 40. That is, the optical path length of the first display light N1 traveling from the first screen 30 toward the user E is longer than the optical path length of the second display light N2 traveling from the second screen 40 toward the user E. Therefore, the distance (display distance) from the user E to the position where the first virtual image V1 is displayed is longer than the distance (display distance) from the user E to the position where the second virtual image V2 is displayed. The HUD device 100 according to the embodiment can display the first virtual image V1 so that it is at a position farther than the second virtual image V2. In the present embodiment, the display distance of the first virtual image V1 is 5 m, and the display distance of the second virtual image V2 is 2 m.

  In addition, the first screen 30 is arranged to have a predetermined angle (including 0 degree) with respect to the optical axis of the first display light N <b> 1 from the first screen 30 toward the user E, and the second screen 40. Similarly, they are arranged so as to have a predetermined angle (including 0 degree) with respect to the optical axis of the second display light N2 from the second screen 40 toward the user E. Note that even when the first screen 30 (second screen 40) has a predetermined angle with respect to the optical axis of the first display light N1, the first curved surface 60 of the concave mirror 60 described later can be The first virtual image V1 and the second virtual image V2 are formed so as to face each other substantially vertically. When the user E visually recognizes the first virtual image V1 (second virtual image V2), the display distance is constant in any region in the first virtual image V1 (second virtual image V2), and the user E can change the focus even if the user E does not move the focus. The entire one virtual image V1 (second virtual image V2) can be easily viewed.

  The plane mirror (relay optical system) 50 is formed by forming a reflective film on the surface of a base material made of, for example, a synthetic resin or a glass material by means of vapor deposition or the like, and is emitted from the first screen 30 and the second screen 40. The one display light N1 and the second display light N2 are reflected toward the concave mirror 60.

  The concave mirror (relay optical system) 60 is obtained by forming a reflective film on the surface of a base material made of, for example, a synthetic resin material by means such as vapor deposition, and the first display light N1 reflected by the plane mirror 30 and the second display light. It is a mirror having a concave free-form surface that further reflects N2 and emits it toward the windshield 200. The first display light N1 and the second display light N2 reflected by the concave mirror 60 pass through the translucent cover 10b provided in the opening 10a of the housing 10 and reach the windshield 200. The first display light N1 and the second display light N2 reflected by the windshield 200 form a first virtual image V1 and a second virtual image V2 at a front position of the windshield 200. Thereby, the HUD device 100 can cause the user E to visually recognize both the virtual image V (the first virtual image V1 and the second virtual image V2) and the outside scene that actually exists in front of the windshield 200. The concave mirror 60 has a function as a magnifying glass, and magnifies the display image M displayed on the projection device 20 and reflects it to the windshield 200 side. That is, the first virtual image V1 and the second virtual image V2 visually recognized by the user E are images in which the first display image M1 and the second display image M2 displayed by the projection device 20 are enlarged. The concave mirror 60 also has a function of reducing the distortion of the first virtual image V1 and the second virtual image V2 caused by the windshield 200 being a curved surface. Below, the specific structure of the projection apparatus 20 is demonstrated.

  As shown in FIG. 1, the projection apparatus 20 includes a display 21 that generates and emits first projection light L1 and second projection light L2, and first projection light L1 and second projection incident from the display 21. A first screen 30 that includes a fold mirror 22 that reflects and reflects the light L2 and an imaging position adjustment mirror 23 that adjusts the imaging distance of the light incident from the fold mirror 22, and is separated from the projection apparatus 20 by a different distance. The first projection light L1 and the second projection light L2 are imaged on the second screen 40 and the second screen 40, respectively.

  The display device 21 includes a reflective display element such as DMD (Digital MicroMirror Device) and LCOS (registered trademark: Liquid Crystal On Silicon), and a transmissive display element such as a TFT (Thin Film Transistor) liquid crystal panel, and is not illustrated. Based on the control signal from the substrate, the first projection light L1 and the second projection light L2 for displaying the first display image M1 and the second display image M2 are emitted toward the fold mirror 22. The display 21 is distorted virtual image V (first virtual image V1, first virtual image V1, first visual image V1, first visual image V1, second mirror 40, flat mirror 50, concave mirror 60, windshield 200, and the like when viewed by the user E. The display image M (first display image M1, second display image M2) distorted in advance in consideration of the optical characteristics and arrangement of the respective optical members is controlled so as not to become two virtual images V2). The

  The fold mirror 22 is obtained by forming a reflective film on the surface of a base material made of, for example, a synthetic resin or a glass material by means such as vapor deposition, and the first projection light L1 and the second projection light emitted from the display 21. This is a plane mirror that reflects L2 to an imaging position adjusting mirror 23 described later. By providing the fold mirror 22, the package of the projection device 20 can be made more compact. A plurality of fold mirrors 22 may be provided between the display 21 and the imaging position adjusting mirror 23, or the fold mirror 22 may be omitted.

  The imaging position adjusting mirror 23 is formed by forming a reflective film on the surface of a base material made of, for example, a synthetic resin material or a glass material by means such as vapor deposition, and receives the first projection light L1 on the same base material. And a second reflecting surface 232 that receives the second projection light L2. In the present embodiment, the first reflecting surface 231 is formed by a flat reflecting surface, and the received first projection light L1 is reflected on the first screen 30 without changing the imaging distance. A first display image M1 is formed on the surface side of the image. The second reflection surface 232 is formed by a free-form surface having a convex reflection surface, and the received second projection light L2 is reflected on the second screen 40 by changing the imaging distance to be longer. A second display image M2 is formed on the surface side of the image.

  That is, the imaging position adjusting mirror 23 in the present embodiment is different in the curved shape of the first reflecting surface 231 that reflects the first projection light L1 and the second reflecting surface 232 that reflects the second projection light L2. The imaging distance can be made different between the first projection light L1 and the second projection light L2 only by receiving the projection light L from one display device 21. Therefore, the first virtual image V1 and the second virtual image V2 visually recognized by the user E can be displayed at different display distances, and the information displayed as the first virtual image V1 and the information displayed as the second virtual image V2. It can be differentiated, and the identifiability of information can be improved. In addition, since the imaging distance between at least the first projection light L1 and the second projection light L2 emitted from the same display 21 can be made different, the cost can be reduced compared with the case where a plurality of displays are provided. Can do.

  Further, since the first reflecting surface 231 and the second reflecting surface 232 in the imaging position adjusting mirror 23 are formed on the same base material, the projection light L from the display 21 is applied to the imaging position adjusting mirror 23. Since at least the imaging distance between the first projection light L1 and the second projection light L2 can be made different by simply irradiating, space saving can be realized without complicating the optical path of the projection light L.

  In addition, the imaging position adjusting mirror 23 in the present embodiment includes a first reflecting surface 231 and a second reflecting surface 232 that change the imaging distance between the first projection light L1 and the second projection light L2 on the same substrate. Therefore, the relative positions of the first reflecting surface 231 and the second reflecting surface 232 are not easily shifted due to an assembly error or the like, and the first projection light L1 and the second projection light L2 are accurately transmitted to the first screen. 30 and the second screen 40.

  Further, the display 21 in the present embodiment does not project the projection light L for generating an image near the boundary between the first reflection surface 231 and the second reflection surface 232 of the imaging position adjustment mirror 23. With such a configuration, even when the projection position of the projection light L with respect to the imaging position adjusting mirror 23 is shifted due to an assembly error or vibration of the HUD device 100, the first display image M1 to be displayed on the first screen 30 is the first display image M1. It is possible to prevent the image from being displayed on the second screen 40.

  In addition, since a part of the imaging position adjustment mirror 23 (first reflection surface 231) in the present embodiment is formed as a flat surface, the projection light L projected from the display device 21 can be reflected without being distorted. . In addition, the design and manufacturing of the imaging position adjusting mirror 23 is facilitated, and the design manufacturing cost can be reduced.

  The above is the description of the HUD device 100 in the present embodiment, but the present invention is not limited to the embodiment and the drawings. Of course, changes (including deletion of components) can be added to these. An example of a modification is shown below.

  In the said embodiment, although the 1st reflective surface 231 was a plane and the 2nd reflective surface 232 demonstrated what is a convex free-form surface, the shape of the reflective surface of the 1st reflective surface 231 and the 2nd reflective surface 232 is the shape. Since the imaging distances of the first projection light L1 and the second projection light L2 need only be different from each other, the present invention is not limited to this. The imaging distance can be increased by making the reflecting surface convex, while the imaging distance can be shortened by making it concave. In addition, the 1st reflective surface 231 and the 2nd reflective surface 232 do not need to have the same curved surface shape in the whole reflective area | region, and may differ with a reflective area | region.

  In the said embodiment, the 1st screen 30 is arrange | positioned so that it may have a predetermined angle with respect to the optical axis of the 1st display light N1 which goes to the user E from the 1st screen 30, and the 2nd screen 40 is the same. Although it has been arranged to have a predetermined angle with respect to the optical axis of the second display light N2 from the second screen 40 toward the user E, the present invention is not limited to this. The first screen 30 and / or the second screen 40 may be arranged so as to be inclined at a predetermined angle or more with respect to the optical axis of the first display light N1 (second display light N2) directed toward the user E. Specifically, as shown in FIG. 3, the first screen 30 is disposed at a predetermined angle or more with respect to the optical axis of the first display light N <b> 1, and the first screen 30 and the display device 21 disposed at a tilt are arranged. In consideration of the optical path length of the first projection light L1 between them, the imaging distance of the first projection light L1 can be gradually changed by gradually changing the curved surface shape of the first reflecting surface 231. Therefore, even when the first screen 30 is tilted by a predetermined angle or more with respect to the optical axis, the first display image M1 can be formed in a wide range (including the entire area) of the first screen 30, and from the user E The first virtual image V1 that has a sense of depth and is not blurred can be visually recognized.

  Further, the inclination of the first screen 30 with respect to the optical axis of the first projection light L1 may be different from the inclination of the second screen 40 with respect to the optical axis of the second projection light L2. With such a configuration, the two virtual images (the first virtual image V1 and the second virtual image V2) can be differentiated in a three-dimensional manner, and each piece of information can be distinguished and easily recognized by the user E.

  In the above embodiment, the image forming position adjusting mirror 23 for adjusting the image forming distance of the first projection light L1 and / or the second projection light L2 emitted from the display 21 has a plurality of connections as shown in FIG. You may comprise by the image position adjustment mirror 23a and the image formation position adjustment mirror 23b.

  Moreover, in the said embodiment, although the 1st reflective surface 231 and the 2nd reflective surface 232 were arrange | positioned on the same base material, you may each arrange | position on a separate base material.

  Further, the first reflecting surface 231 and the second reflecting surface 232 may be formed of a continuous reflecting film, and the reflecting film is not formed near the boundary between the first reflecting surface 231 and the second reflecting surface 232. Also good.

  Moreover, in the said embodiment, although the 1st screen 30 and the 2nd screen 40 were made into the substantially rectangular shape, even if the shape of the 1st screen 30 and the 2nd screen 40 is polygonal shapes, such as a hexagon and an octagon, Good.

  Moreover, in the above description, in order to make an understanding of this invention easy, description of the unimportant known technical matter was abbreviate | omitted suitably.

100 HUD device (head up display device), 10 housing, 20 projection device, 21 display, 22 fold mirror, 23 imaging position adjustment mirror, 30 first screen, 40 second screen, 50 plane mirror, 60 concave mirror, L Projection light, L1 first projection light, L2 second projection light, M1 first display image, M2 second display image, N1 first display light, N2 second display light, V virtual image V1 first virtual image V2 second virtual image

Claims (16)

A display that emits projection light for displaying a display image at a predetermined position;
An imaging position adjusting mirror that receives the projection light emitted from the display and reflects the incident projection light by changing an imaging distance of at least a part of the projection light; and
The projection light reflected by the imaging position adjustment mirror is imaged as a real image at a position where the distance from the display is different.
A projection apparatus characterized by that. The imaging position adjusting mirror is configured to reflect a part of the projection light as a first projection light having a first imaging distance toward a predetermined region, and a part of the projection light. A second reflecting surface that reflects toward a region different from the first projection light as a second projection light having a second imaging distance shorter than the first imaging distance,
The projection apparatus according to claim 1. The first reflective surface or / and the second reflective surface have a convex reflective surface that increases the imaging distance of the projection light.
The projection apparatus according to claim 2. The first reflecting surface and the second reflecting surface are formed on the same substrate.
The projection apparatus according to claim 2. The indicator does not project the projection light near a boundary between the first reflecting surface and the second reflecting surface;
The projection apparatus according to claim 2. Either the first reflecting surface or the second reflecting surface is a plane,
The projection apparatus according to claim 2. The first reflective surface or / and the second reflective surface have a curved surface that gradually changes the imaging distance of the projection light according to the angle of view of the display image.
The projection apparatus according to claim 2. In a head-up display device that projects a display image on a projection surface and visually recognizes the display image as a virtual image,
A projection unit for emitting projection light;
The projection light emitted from the projection unit is received, converted into a plurality of projection lights having different imaging distances by changing the imaging distance of at least some of the incident projection light, and reflected. An imaging position adjustment mirror;
A second screen that forms projection light having a long imaging distance as a real image among the projection light;
A first screen that is arranged at a position farther from the projection surface than the second screen and forms a projection light having a short imaging distance as a real image out of the projection light,
A head-up display device. The imaging position adjusting mirror includes a first reflecting surface that reflects a part of the projection light as a first projection light having a first imaging distance toward the first screen, and a part of the projection light. A second reflecting surface that reflects toward the second screen as a second projection light having a second imaging distance shorter than the first imaging distance,
The head-up display device according to claim 8. The first reflective surface or / and the second reflective surface have a convex reflective surface that increases the imaging distance of the projection light.
The head-up display device according to claim 9. The first reflecting surface and the second reflecting surface are formed on the same substrate.
The head-up display device according to claim 9. The projection unit does not project the projection light near a boundary between the first reflection surface and the second reflection surface;
The head-up display device according to claim 9. Either the first reflecting surface or the second reflecting surface is a plane,
The head-up display device according to claim 9. The first screen or / and the second screen are arranged to be inclined with respect to the optical axis of the projection light.
The head-up display device according to claim 9. The inclination of the first screen with respect to the optical axis of the projection light is different from the inclination of the second screen with respect to the optical axis of the projection light.
The head-up display device according to claim 14. The first reflective surface or / and the second reflective surface have a curved surface that gradually changes the imaging distance of the projection light according to the angle of view of the display image.
The head-up display device according to claim 14.

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