JP2012163613A - Virtual image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a virtual image display device which can specify a position of eye with high accuracy.SOLUTION: Display light output from a projection optical system 11 is image-formed at a diffusion region 13a of a screen 13, and is reflected and magnified by a concave mirror 15 to be projected onto a windshield 21. With the windshield 21 used as a combiner, the display light arrives at an eye point 25 of a driver located at an eye-box 23. Further, the projection optical system 11 projects an infrared light onto the same optical path as an optical path (optical axis 31) of the light that arrives at the eye point 25. The projected infrared light is reflected by the eye of the driver that exists at the eye point 25 of the driver, and arrives at the screen 13 through the windshield 21 and the concave mirror 15. The light that arrives at the screen 13 is reflected to a photo-receiver 17 in a reflection region 13b that is provided at a place other than the diffusion region 13a, and is image-formed at the photo-receiver 17. The controller 19 specifies a position of eye from an imaging position of the reflected light received by the photo-receiver 17.

Description

  The present invention relates to a virtual image display device that displays a virtual image in front of a combiner provided on a moving body.

  Conventionally, a virtual image display device (head-up display) that displays various information in a virtual image in front of a combiner or windshield mounted on a vehicle has been proposed. In this virtual image display device, since a virtual image is displayed in the foreground of the vehicle that the driver is viewing, the line of sight movement and focus are compared with the case where the driver visually recognizes an instrument panel mounted on the dashboard. The load of adjustment can be reduced.

  In addition, the virtual image can be used as a superimposed display that provides information that is easy to understand for the driver by superimposing it on some foreground object (car, intersection, pedestrian, etc.) or displaying it in the vicinity thereof. .

  As such a virtual image display device, there is a virtual image display device 101 configured as shown in FIG. The image projected from the projection optical system 103 once forms an image on the screen 105 (a micromirror array or a holographic diffuser that diffuses light rays is formed).

  Further, this image is reflected and magnified by the concave mirror 107, passes through an opening cover of a device (not shown), is reflected by the combiner 109, reaches the driver's eye 113 in the eye box (viewing zone) 111, and receives a virtual image from the driver. It is visually recognized as 115. At this time, the display element of the projection optical system 103, the projected image on the screen 105, and the virtual image 115 are in a conjugate relationship. As an example of an optical system having a similar configuration, there is an optical system described in Patent Document 1.

  Note that the virtual image display device 101 has an advantage that an image can be enlarged in two stages, so that aberration can be suppressed and a clear virtual image can be formed. Furthermore, the exit pupil of the projection optical system 103 (a diaphragm image viewed from the screen side) and the eye box 111 are in a conjugate relationship. Further, when the screen 105 is configured so that the light rays emitted from the exit pupil are condensed (illuminated) over the entire eye box 111, a bright image can be efficiently obtained.

  If the virtual image display device is configured such that the position of the eye box is wide, that is, the virtual image can be viewed from a wide range, the virtual image is distorted or the virtual image becomes dark. Therefore, it is preferable that the eye box has a limited range in accordance with the position of the driver's eyes. Conventionally, there is a mechanism that incorporates a mechanism for rotating a concave mirror so that the position of the eye box can be adjusted according to the height of the driver's back (see, for example, Patent Document 2).

  The device described in the above-mentioned Patent Document 2 requires a driver to adjust the device by pressing the operation button himself, which requires troublesome operation, and displays a virtual image when the driver's posture changes and the eye position changes. In some cases, the position of the image may be shifted or invisible. In order to automatically set the concave mirror to an appropriate rotation angle, it is necessary to accurately specify the position of the driver's eyes.

  Further, in order to use the virtual image display device as the above-described superimposed display, not only the foreground object is detected by a camera or a radar, but also the position of the driver's eyes is specified, and the foreground object and the driving are identified. It is necessary to display a virtual image on (or in the vicinity of) a straight line connecting a person's eyes. In order to realize these functions, it is necessary to accurately specify the position of the driver's eyes.

On the other hand, there is an obstacle detection device for a vehicle in which an infrared camera or an infrared illumination lamp is arranged outside the instrument panel, and an eyeball is photographed to detect a line-of-sight direction (see Patent Document 3).
However, in the apparatus described in Patent Document 3, an infrared camera and an infrared illumination lamp are installed outside the instrument panel, and the design is very limited. Also, since there is no infrared camera or infrared illumination lamp in front of the driver, the driver's eyes are blocked by other parts of the face and parts of the car such as the steering wheel, resulting in poor position detection accuracy. May be.

  On the other hand, a display device for displaying a virtual image, in which a light receiving means (photographing device) for photographing a driver's eyes is arranged on the optical axis of an optical system for displaying a virtual image, and a display device for detecting a positional deviation of the eye is proposed. (See Patent Document 4).

  In this display device, since the image captured by the light receiving means can be captured from the front of the driver, it is possible to reduce the influence of the camera and illumination being shielded by other parts of the face, the handle, and the like.

JP 2003-207743 A JP 2004-347633 A JP-A-6-230132 Japanese Patent No. 3727078

In order to satisfactorily grasp the position of the eye, it is preferable that the reflected light of the infrared light reflected by the eye reaches the light receiving means with sufficient intensity.
However, in the display device disclosed in Patent Document 4, infrared light that illuminates the driver's face is arranged in a position not specifically limited in the vehicle interior or inside the optical unit. As a result, the reflected infrared light may not reach the light receiving means with sufficient intensity as a result of being irradiated near the eye box or being blocked by the handle or the driver's body. Moreover, when the light irradiated from infrared light illumination is strengthened, there is a possibility of damaging the eyes even with non-visible light such as infrared light.

As described above, in the display device disclosed in Patent Document 4, the reflected light of the infrared light cannot be obtained with sufficient intensity by the light receiving means, and thus the eye position may not be specified with high accuracy.
The present invention has been made in view of the above-described problems, and an object thereof is to provide a virtual image display device capable of specifying the position of the eye with high accuracy.

  The invention according to claim 1, which has been made to solve the above-described problem, projects display light for displaying an image, causes the projected light to reach a combiner provided in the moving body, and transmits the display light to the combiner. The present invention relates to a virtual image display device that displays an image in front of the combiner by reflecting the light with a combiner and reaching the eyes of a moving passenger, and has the following characteristics.

  This virtual image display device projects invisible light toward the passenger in an optical path that overlaps the optical path of the display light. The projected non-visible light has a light receiving means for receiving reflected light reflected by the passenger's eyes, and the position of the passenger's eyes is determined based on the position where the light receiving means has received the reflected light. Identify.

  Various optical systems can be arranged between the means for outputting the display light and the combiner to cause the display light to reach the combiner. In this virtual image display device, the display light is projected by the means for projecting the display light. A screen is disposed at the imaging position of the displayed light. The screen includes a diffusion region for diffusing the display light and a reflection region for reflecting the reflected light reflected by the passenger's eyes toward the light receiving means.

  In the virtual image display device configured as described above, the position of the occupant's eyes can be specified based on the position where the light receiving means receives the reflected light. As the light receiving means, for example, a matrix sensor such as a CCD or CMOS having sensitivity to invisible light can be employed. In this case, the position where the reflected light is received is the position of the reflected light detected by the matrix sensor as the light receiving means.

  In the virtual image display device, since the invisible light is projected toward the passenger's eyes, the light receiving means can obtain the reflected light of the invisible light satisfactorily. And since the invisible light is projected toward the occupant through an optical path that overlaps the optical path of the display light, it is projected toward the occupant from the front of the occupant without being blocked by the handle or the occupant's body. Will be. Accordingly, since the passenger's eyes can be illuminated sufficiently brightly without increasing the intensity of invisible light, the reflected light reaches the light receiving means with sufficient intensity, and the position of the eyes is specified with high accuracy. be able to. In addition, damage to the eyes can be reduced.

  In addition, the virtual image display device of the present invention is provided with a non-visible light source for specifying the position of the eye, so that it does not need to be placed in the room of the moving body, and there are few design restrictions. In addition, since an optical system for projecting display light to invisible light projection can be used, the number of optical members such as reflectors used only for invisible light projection can be reduced, and the apparatus can be miniaturized.

Moreover, since the reflected light from the eye is detected and the position of the eye is specified, a complicated process for specifying the eye from the entire face image is not necessary.
An example of invisible light is infrared light.

  Further, in the virtual image display device, a screen used for displaying a virtual image can be used as a configuration for receiving reflected light, and the virtual image display device can be reduced in size. In addition, the light reflected by the reflection area mainly reaches the light receiving means, and the reflected light that is diffused and blurred by the screen (in the diffusion area) is difficult to reach. it can.

  As the light receiving means, an imaging device (image sensor) having sensitivity to at least projected (reflected by the eye) invisible light may be used. The position where the light receiving means is arranged is not particularly limited, but it is preferable to take a picture from the front of the passenger. However, if the light receiving means is arranged in front of the occupant, the field of view is obstructed. Therefore, the light receiving means may be arranged inside the virtual image display device so that reflected light traveling in the opposite direction along the optical path of display light or invisible light can be photographed. .

  The virtual image display device may have a conjugate relationship as shown below. That is, a display surface that outputs display light, a screen diffusion region, and a virtual image have a conjugate relationship, an exit pupil of a means that outputs display light, and an eye box that is an area where a passenger can visually recognize an image. Are in a conjugate relationship, and the eye box and the light receiving means are in a conjugate relationship.

  By arranging the components so as to have such a conjugate relationship, it is possible to make the passenger see the virtual image well, and to improve the detection accuracy of the light receiving position of the reflected light by the light receiving means.

  A means for adjusting the optical paths of the display light and the invisible light may be provided so that when the eye position is specified, the eye box moves to the eye position. For example, as in the virtual image display device according to claim 3, a reflection plate that reflects display light and invisible light is provided, and a means for adjusting the angle of the reflection plate according to the position of the eye is provided. It is conceivable to provide means for adjusting the shape of the image indicated by the display light as in the virtual image display device according to claim 4.

In the virtual image display device configured as described above, the position of the eye box where the virtual image can be visually recognized can be automatically corrected or the distortion of the image can be reduced.
The means for adjusting the shape of the image described above may be, for example, a means for changing the position where the display light is actually output in the display screen that outputs the display light. In addition, it is conceivable that the image is distorted in advance so as to cancel out distortion (particularly distortion generated by changing the eye position) that occurs when the passenger visually recognizes the virtual image.

In addition, a planar mirror etc. may be used for the reflecting plate mentioned above, and a concave mirror and a convex mirror may be sufficient as it.
The diffusion region and the reflection region may have different curvatures as described in claim 5, or have optical axes in different directions as described in claim 6. May be.

  If the curvatures of the diffusion region and the reflection region are different, the imaging distance of the reflected light reflected by the reflection region can be made different from the imaging distance from the means for projecting the display light to the diffusion region. Further, if the optical axes of the diffusion region and the reflection region are different, the reflected light can be reflected while being shifted from the optical path of the display light.

  That is, by configuring the screen as described above, the degree of freedom of arrangement of the light receiving means can be increased. Also, by making the optical axes different as described above, it becomes difficult for the reflected light reflected by the diffusion region to reach the light receiving means, so that the reflected light can be prevented from becoming noise.

By the way, as a means for projecting display light, various known configurations for forming an image can be employed.
Further, as in claim 7, the means for projecting the display light and the means for projecting the invisible light are formed by one image display, and the display light and the invisible light are predetermined. It may be switched and projected at a period of

  With the virtual image display device configured as described above, it is not necessary to separately provide means for projecting display light and means for projecting invisible light, and the virtual image display device can be reduced in size. . Further, since the display light and the invisible light are output from the same display device, their optical paths can be easily overlapped.

  In addition, when projecting invisible light, the image display device may be configured to project invisible light from substantially the entire display surface of the image display device as described in claim 8. . Since the non-visible light is projected to specify the position of the occupant's eyes, the reflected light of the eyes can be detected from a wide range by projecting to the wide range, which is convenient.

  Further, the means for projecting display light and the means for projecting invisible light may be arranged separately. In that case, you may comprise as described in Claim 9. The virtual image display device according to claim 9 includes a filter that transmits display light and reflects invisible light, and is disposed on an optical path of the display light, and reflects the invisible light to the filter. Thus, the invisible light is projected so as to overlap the optical path of the display light.

  Moreover, the virtual image display device of the present invention is configured to have a wavelength selection film that is disposed on the surface of the combiner and reflects light of at least one of display light and invisible light as described in claim 10. May be.

  With the virtual image display device configured as described above, display light or non-visible light can be efficiently reflected to the passenger. Thereby, the brightness | luminance of display light can be raised or the power consumption for making a virtual image of the same brightness | luminance visually recognized can be reduced. Further, it is possible to reduce the power consumption of the invisible light projection necessary for the light receiving means to receive the reflected light of the invisible light having the same intensity.

  The virtual image display device of the present invention projects display light and invisible light onto a combiner. However, as described in claim 11, display light and invisible are displayed on a windshield of a moving body used as a combiner. If light is projected, there is no need to provide a separate combiner, which is convenient.

The side view which shows schematic structure of the virtual image display apparatus of an Example. Schematic diagram showing the internal configuration of the projection optical system Side view showing the screen Enlarged perspective view showing a micromirror array Block diagram showing the configuration of the control device Side view showing a state where a wavelength selective film is provided on the windshield Schematic diagram showing the internal configuration of a modified projection optical system Side view showing a conventional virtual image display device

Embodiments of the present invention will be described below with reference to the drawings.
[Example]
(1) Configuration A virtual image display device 1 according to the present embodiment is used by being mounted on a vehicle (moving body). As shown in FIG. 1, a projection optical system 11, a screen 13, a concave mirror 15, and a light receiving device. 17 and a control device 19. The projection optical system 11 corresponds to the display light projection means, the invisible light projection means, and the image display of the present invention, the concave mirror 15 corresponds to the reflector of the present invention, and the light receiving device 17 corresponds to the light reception means of the present invention. It corresponds to. The screen 13 and the concave mirror 15 correspond to the optical system of the present invention.

The general function of each component of the virtual image display device 1 will be described. An optical axis 31 in FIG. 1 is a schematic diagram showing the center of the optical path of the light projected from the projection optical system 11.
An image (display light) output from the projection optical system 11 forms an image in a predetermined diffusion region 13 a on the screen 13. This image is reflected and magnified by the concave mirror 15 and projected onto the windshield 21 provided in the vehicle. The windshield 21 is used as a combiner to reach the viewpoint 25 of the driver (passenger) located in the eye box 23. The driver can view the image output from the projection optical system 11 as an enlarged virtual image (virtual image display image) 27 at a point in front of the windshield 21.

  The eye box 23 is an area where the driver can visually recognize the image, and the position of the eye box 23 is adjusted by the image projected by the projection optical system 11 (display area on the image display screen) and the angle of the concave mirror 15. It is. Here, the display surface of the display element (LCOS 49) of the projection optical system 11, the image formed on the diffusion region 13a of the screen 13, and the virtual image 27 are in a conjugate relationship. Furthermore, the exit pupil of the projection optical system 11 that projects an image and the eye box 23 are in a conjugate relationship via the diffusion region 13a.

  Further, the projection optical system 11 projects infrared light (corresponding to invisible light in the present invention) on the same optical path as the display light reaching the viewpoint 25. Similarly to the display light, the infrared light is projected onto the windshield 21 via the diffusion region 13a of the screen 13 and the concave mirror 15, reflected by the windshield 21, and reaches a wide range including the eye box 23. That is, the exit pupil of the projection optical system 11 that projects infrared light and the eye box 23 are in a conjugate relationship via the diffusion region 13a.

  The projected infrared light is reflected by the driver's eyes (portions where the position of the eyes such as the retina and cornea can be determined) existing at the driver's viewpoint 25, and passes through the windshield 21 and the concave mirror 15 to the screen 13. To reach. The light that reaches the screen 13 is reflected toward the light receiving device 17 by the reflection region 13b provided at a position different from the diffusion region 13a, and forms an image on the light receiving device 17. That is, the eye box 23 and the light receiving device 17 are in a conjugate relationship via the reflection region 13b. Hereinafter, when simply referred to as reflected light, it refers to infrared light reflected by the driver's eyes.

  The control device 19 identifies the position of the eye from the imaging position of the reflected light received by the light receiving device 17. Then, the driving device 33 provided on the concave mirror 15 is operated to change the direction of light projected from the concave mirror 15 onto the windshield 21, or the position of the image output by the projection optical system 11 (display on the display screen of the image). By adjusting the area, the position of the eye box 23 is adjusted, and light is projected to a position that matches the viewpoint 25 of the driver. The control device 19 corresponds to the position specifying means in the present invention.

Next, each component of the virtual image display device 1 will be described in detail.
The projection optical system 11 outputs display light for forming an image. FIG. 2 is a schematic diagram showing the internal configuration of the projection optical system 11.

  The projection optical system 11 includes four LED elements 41a to 41d. The LED element 41a is an LED (IR-LED) that emits infrared light. Further, the LED elements 41b to 41d respectively emit light of three colors (visible light) of R (red), G (green), and B (blue) for displaying a virtual image. These LED elements 41b to 41d are light sources for forming display light.

  Light emitted from the LED elements 41 a to 41 d is collimated by a condensing lens 43 arranged for each LED element, coupled by a dichroic mirror 45, and passed through a polarization beam splitter (PBS) 47 to be LCOS (Liquid Crystal on). (Silicon) 49.

  Since the LCOS 49 can change the polarization direction and the PBS 47 is transmitted or reflected according to the polarization direction, an image can be generated by turning on / off the pixels on the LCOS 49. That is, the LCOS 49 becomes an image display screen. The light beam reflected by the LCOS 49 passes through the PBS 47 and is projected to the outside through the projection lens unit 51 including a plurality of lenses 51 a and a diaphragm 51 b, and an image on the LCOS 49 is projected on the screen 13.

  As the light source, a laser may be used instead of the LED element. When the laser is used as the light source, the image may be projected onto the screen 13 by scanning the laser using a scanner or a Bolgon mirror. Further, a transmissive LCD or DMD (Digital Micromirror Device) may be used as the display element instead of the LCOS 49.

  Visible light (LED elements 41b to 41d) and infrared light (LED element 41a) may be irradiated at different timings or simultaneously. Of course, they may be mixed.

  When irradiating at different timings, for example, it is conceivable that one cycle is R-> G-> B-> IR (infrared light) and time-division driving is performed, and this cycle is repeated. At the timing of irradiating R, G, and B, the pixels on the LCOS 49 are turned ON / OFF according to the design and color of the virtual image (image) to be displayed. At the timing of IR irradiation, all pixels (full screen) or substantially full screen on the LCOS 49 may be turned on, or only a part of the regions may be turned on.

As another example, there is a method in which the cycle of R → G → B is repeated a plurality of times, IR is irradiated once or a plurality of times, and the cycle returns to the cycle of R → G → B again.
As described above, the advantage of irradiating visible light and infrared light at different timings is that infrared light can be irradiated independently even when there is no virtual image display that is always displayed or when the design of the virtual image display is small, It is possible to detect a stable eye position.

  In the case of simultaneously irradiating visible light and infrared light, IR is irradiated in synchronism with the timing when any of R, G, and B is irradiated. IR may be irradiated in synchronization with all of R, G, and B. An advantage of these simultaneous irradiations is that the circuit configuration is simplified.

Whichever method is employed, ON / OFF of the LED elements 41 a to 41 d is controlled by the control device 19.
Note that the display image (display surface) of the LCOS 49, the projection image on the screen 13, and the virtual image 27 are in a conjugate relationship.

  As described above, the screen 13 includes the diffusion region 13a and the reflection region 13b. A side view of the screen 13 of this embodiment is shown in FIG. In this embodiment, both the diffusion region 13a and the reflection region 13b have a convex shape.

  The diffusion region 13a serves to diffuse light rays from the projection optical system 11 and to uniformly project light rays onto the driver's eye box 23. A micromirror array can be used as the diffusion region 13a.

  A micromirror array is shown in FIG. A large number of micromirrors are formed in an array on a flat or curved surface. An example of the pitch of the microarray is 10 μm to 200 μm. The curvature of the micromirror, for example, is 100 μm to 1000 μm. The pitch or curvature in the vertical and horizontal directions may be changed. Either a concave shape or a convex shape, or may be alternately arranged. The arrangement pattern may be a lattice or a hexagonal close-packed structure. These parameters are adjusted depending on the size of the driver's eye box 23.

  Other examples of the diffusion region 13a include a holographic diffuser and a diffuser in which a reflective material such as aluminum is applied to ground glass, but in order not to reduce the efficiency of light irradiation to the eye box 23, A diffuser capable of controlling directivity such as a micromirror array or a holographic diffuser is desirable.

  Returning to FIG. The reflection region 13b is formed as a gently curved surface having a smaller curvature than the diffusion region 13a, that is, a larger curvature radius. Therefore, the point at which the infrared light reflected and returned by the driver's eyes forms an image (a point on the light receiving device 17) is imaged at a shorter distance than the light beam passing through the diffusion region 13a. Further, since the optical axis 13d of the reflection region 13b is inclined with respect to the optical axis 13c of the diffusion region 13a, the direction of the reflected light is directed in a direction different from that of the diffusion region 13a. By utilizing such an action, the light receiving device 17 can be installed at a location different from the projection optical system 11.

  The concave mirror 15 is a mirror having a curved inner surface as a mirror surface and an enlarged image of an incident image, and has a known configuration. In this embodiment, the concave mirror 15 is provided with a driving device 33 so that the reflection direction of light from the diffusion region 13a can be adjusted by moving the optical axis.

  The light receiving device 17 is a matrix sensor such as a CCD or CMOS having sensitivity to infrared light, and receives the infrared light reflected by the driver's eyes and detects its imaging position. The detected position information is transmitted to the control device 19. The light receiving device 17 detects reflected light that has passed through an optical path along an optical path on which display light and infrared light are projected in the opposite direction.

  The control device 19 controls the overall operation of the virtual image display device 1 and is connected to various ECUs and sensors (not shown) mounted on the vehicle and projects various information based on output signals from them. The optical system 11 is made to output. A block diagram showing the configuration of the control device 19 is shown in FIG. The control device 19 includes a light reception processing unit 53, a projection processing unit 55, a light beam deflection processing unit 57, and the like.

  The light reception processing unit 53 can identify the position of the driver's eyes from the position information in which the infrared light reflected by the eyes forms an image on the light receiving device 17. This is because the eye box 23 and the light receiving device 17 are in a conjugate relationship, so that both eyes of the driver illuminated by infrared light become two pseudo point light sources, and these two point light sources are on the light receiving device 17. This is because an image is formed as two points. That is, if the eye position is moved, the image point on the light receiving device 17 is moved accordingly, and thus the eye position can be easily extracted. For this reason, there is an advantage that the memory capacity and the system processing speed can be reduced as compared with the method in which the entire face image is taken with a camera or the like and the eye position is extracted by a technique such as pattern matching.

  The projection processing unit 55 includes a display element processing unit 55a and a light source processing unit 55b. The display element processing unit 55a controls ON / OFF of each pixel of the LCOS 49 to form an image to be displayed. The light source processing unit 55b controls ON / OFF of the LED elements 41a to 41d. The LED elements 41a to 41d operate in synchronization with the LCOS 49.

  Further, the display element processing unit 55 a adjusts the position for displaying the image on the display screen of the LCOS 49 based on the eye position specified by the light receiving processing unit 53. Specifically, the position on the screen for displaying the image is adjusted so that the image (virtual image) can be appropriately visually recognized at the specified eye position, and the distortion of the virtual image generated at the position is offset. , An image with distortion in advance is displayed. The display element processing unit 55a that performs the operation corresponds to the image adjustment unit in the present invention.

  The beam deflection processing unit 57 sets an appropriate position of the concave mirror 15 based on the eye position specified by the light receiving processing unit 53, and operates the driving device 33 so that the concave mirror 15 moves (rotates) to that position. Let Specifically, the angle is adjusted so that the virtual image can be appropriately visually recognized at the specified eye position. The driving device 33 corresponds to the angle adjusting means in the present invention.

(2) Action and Effect of Invention In the virtual image display device 1 of the present embodiment, the position of the driver's eye (viewpoint 25) is specified based on the position where the light receiving device 17 receives the reflected light (the position of the imaging point). However, since the infrared light is projected from the front of the driver so as to overlap the optical path of the display light, it can be projected toward the driver without being blocked by the steering wheel or the driver's body. it can. Accordingly, the driver's eyes can always be sufficiently brightly illuminated without increasing the intensity of infrared light, and the position of the eyes can be grasped well.

In the virtual image display device 1, the position of the eye box 23 where the virtual image 27 can be visually recognized is automatically corrected according to the position of the eye, and image distortion can be reduced.
Further, in the virtual image display device 1, the screen 13 used for displaying the virtual image 27 can be used as a configuration for receiving reflected light, and the virtual image display device 1 can be downsized.

  The reflected light is reflected by the reflection region 13 b on the screen 13 and reaches the light receiving device 17. If the entire surface of the screen 13 is configured as a diffusion region, the light reaching the light receiving device 17 becomes blurred. However, in the virtual image display device 1 of the present embodiment, the light reflected by the reflection region 13b is received by the light receiving device. Since it reaches 17, the light is not blurred and the position of the eye can be detected with high accuracy.

  In addition, since the diffusion region 13a and the reflection region 13b in the screen 13 are different in both curvature and optical axis, the light receiving device 17 can be arranged at a position different from the projection optical system 11 as described above. The degree of freedom of arrangement can be increased. In addition, since the reflected light reflected by the diffusion region 13a is difficult to reach the light receiving device 17, it is possible to prevent the reflected light from becoming noise and lowering the accuracy of eye position specification.

  Further, in the virtual image display device 1 of the present embodiment, display light and infrared light are projected from one projection optical system 11, and the virtual image display device 1 is reduced in size. Further, since the display light and the infrared light are projected to the driver via the same optical system, it is not necessary to provide separate optical systems, and the apparatus can be miniaturized.

Further, in the virtual image display device 1 of the present embodiment, since the infrared light source and the light receiving device 17 are not arranged around the instrument panel or the like, there are few design restrictions in the vehicle compartment.
Further, since the virtual image display device 1 according to the present embodiment detects the reflected light from the eye and specifies the position of the eye, a complicated process for specifying the eye from the image of the entire face is not necessary.

[Modification]
As mentioned above, although the Example of this invention was described, it cannot be overemphasized that this invention can take a various form, as long as it belongs to the technical scope of this invention, without being limited to the said Example at all.

  For example, in the above-described embodiment, the configuration in which the reflection region 13b is provided on the screen 13 is illustrated, but a reflection plate may be provided separately from the screen 13, and the reflection plate may be used in place of the reflection region 13b.

Moreover, in the said Example, although the structure which projects from all the display surfaces of LCOS49 was illustrated when projecting infrared light, the structure which projects infrared light from only a part of display surface may be sufficient.
In addition, a wavelength selection film that reflects light having the wavelength of display light may be provided on the windshield 21. A state in which the wavelength selection film 61 is provided on the windshield 21 is shown in FIG. A rugate filter is used as the wavelength selection film 61. The rugate filter is a kind of dielectric multilayer film and has the property of increasing the reflectance only in a specific wavelength band.

  The windshield of an automobile needs to secure a foreground transmittance of 70% or more. Therefore, when the wavelength selection film 61 is not provided on the windshield 21, the reflectance of the display light projected on the windshield 21 is 30% or less, and the light use efficiency is lowered, so that the brightness of the visible virtual image is reduced or consumed. Electric power will rise.

  As described above, the rugate filter has the property of increasing the reflectance only in a specific wavelength band. If this wavelength band is made equal to the wavelength band of the LED elements 41a to 41d, which are the light sources of the projection optical system 11, and arranged as shown in FIG. 6, the reflectance of the display light used for the virtual image increases, so the brightness of the virtual image The required power consumption can be reduced. Similarly, the power of infrared light can be reduced, so that power consumption can be reduced. Furthermore, if the wavelength of infrared light contained in sunlight or the like is equal to the infrared wavelength used to identify the position of the eye, sunlight may become disturbance noise, which may reduce the accuracy of position identification. If the disturbance noise is cut using, it can be expected that the detection accuracy increases. The wavelength selection film is not limited to the rugate filter, and may be a hologram.

  Moreover, in the said Example, although the structure which both the projection optical system 11 display light and infrared light project from the projection optical system 11 was illustrated, they may be projected from a different position. .

  For example, as shown in FIG. 7, the LED element 41 a can be projected through the condenser lenses 63 and 65 and the diaphragm 67 and reflected by the filter 69. The filter 69 transmits display light and reflects infrared light, and is disposed on the optical path of the display light. By comprising in this way, infrared light can be projected so that it may overlap with the optical path of display light.

  At this time, the exit pupil of the projection lens unit 51 for virtual image display (image of the diaphragm 51b viewed from the screen 13 side) and the exit pupil of the condenser lens of the LED element 41a (image of the diaphragm 67) have the same optical path length from the screen 13. In place. Therefore, the two exit pupils are in a conjugate relationship with the eye box 23.

  In the above configuration, since the projection optical system for projecting visible light and infrared light is separate, the projection of the infrared light by the LED element 41a needs to be interlocked with the time-division driving of the LED elements 41b to 41d. There is no.

DESCRIPTION OF SYMBOLS 1 ... Virtual image display apparatus, 11 ... Projection optical system, 13 ... Screen, 13a ... Diffusion area | region, 13b ... Reflection area | region, 15 ... Concave mirror, 17 ... Light-receiving device, 19 ... Control apparatus, 21 ... Wind shield, 23 ... Eye box, 25 ... viewpoint, 27 ... virtual image, 31 ... optical axis, 33 ... drive device, 41 ... LED element, 43 ... condensing lens, 45 ... dichroic mirror, 47 ... PBS, 49 ... LCOS, 51 ... projection lens unit, 51a ... Lens, 51b ... Aperture, 53 ... Light reception processing unit, 55 ... Projection processing unit, 55a ... Display element processing unit, 55b ... Light source processing unit, 57 ... Light deflection processing unit, 61 ... Wavelength selection film, 63,65 ... Condensing light Lens: 67 ... Aperture, 69 ... Filter, 101 ... Virtual image display device, 103 ... Projection optical system, 105 ... Screen, 107 ... Concave mirror, 109 ... Combiner, 111 ... Eye box 113 ... eye, 115 ... virtual image

Claims (11)

Display light projecting means for projecting display light for displaying an image, and an optical system for causing the light projected by the display light projecting means to reach a combiner provided on a moving body, and the display light by the combiner In a virtual image display device that displays a virtual image in front of the combiner by reflecting and reaching the eyes of a passenger of the moving body,
Non-visible light projection means for projecting invisible light toward the passenger in an optical path overlapping with the optical path of the display light projected from the display light projection means,
A light receiving means for receiving the reflected light reflected by the occupant's eyes, the invisible light projected from the invisible light projecting means;
Position specifying means for specifying the position of the eyes of the occupant based on the position where the light receiving means receives the reflected light, and
The optical system includes a screen disposed at an imaging position of display light projected by the display light projection unit,
The screen includes a diffusion region for diffusing display light projected by the display light projection unit, and reflected light obtained by reflecting the invisible light projected from the non-visible light projection unit with the eyes of the occupant. A virtual image display device comprising: a reflective region that reflects toward the screen. The display surface that outputs the display light in the display light projection means, the diffusion region of the screen, and the virtual image are in a conjugate relationship,
The exit pupil of the display light projection means and the eye box that is an area where the passenger can visually recognize the image are in a conjugate relationship,
The virtual image display device according to claim 1, wherein the eye box and the light receiving unit are in a conjugate relationship. The optical system has a reflecting plate that reflects the light projected by the display light projection unit and the invisible light projection unit,
The virtual image display device according to claim 1, further comprising an angle adjusting unit that adjusts an angle of the reflecting plate in accordance with the position of the eye specified by the position specifying unit. 4. The image processing apparatus according to claim 1, further comprising an image adjusting unit that adjusts a shape of an image projected by the display light projecting unit according to the position of the eye specified by the position specifying unit. The virtual image display device according to claim 1. The virtual image display device according to any one of claims 1 to 4, wherein the diffusion region and the reflection region have different curvatures. The virtual image display device according to any one of claims 1 to 5, wherein the diffusion region and the reflection region are configured such that their optical axes are directed in different directions. The display light projection means and the invisible light projection means are one image display capable of outputting the display light and the invisible light,
The virtual image according to any one of claims 1 to 6, wherein the image display unit projects the display light and the invisible light by switching at a predetermined cycle. Display device. The virtual image display device according to claim 7, wherein the image display device projects invisible light from substantially the entire display surface of the image display device. The invisible light projection means includes a filter that transmits the display light and reflects the invisible light, and is disposed on an optical path of the display light, and reflects the invisible light to the filter. The virtual image display device according to any one of claims 1 to 8, wherein the non-visible light is projected so as to overlap an optical path of the display light. The wavelength selection film that is disposed on the surface of the combiner and reflects light of at least one wavelength of the display light and the invisible light. 10. Virtual image display device. The said display light projection means and the said invisible light projection means project the said display light and the said invisible light on the windshield of the said mobile body used as the said combiner. The virtual image display device according to any one of the above.