JPH1195144A - Video display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact and inexpensive video display device which is simple in constitution and is capable of sharing a scanning member. SOLUTION: The light beam tram a light source 1L for the meet eyes and the light beam from a light source 1R for the right eye are introduced to the eyes EL, ER under scanning with these beams in at least one direction so that the two-dimensional images may be observed by both right and left eyes. A horizontal scanning mirror 5 consists of a plane both side mirror and oscillates in such a manner that its one reflection surface deflects the light beam from the light source 1L and simultaneously the other reflection surface deflects the light beam from the light source 1R, thereby causing the simultaneous horizontal scanning of the two light beams.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display device, for example, an HMD (h) displaying a virtual image image.
The present invention relates to a scanning type video display device suitable for ead mounted display and the like.

[0002]

2. Description of the Related Art A conventional scanning type image display apparatus known in the related art has a left-eye scanning member and a right-eye scanning member so that a two-dimensional image can be observed with both the left and right eyes. Were individually provided. Therefore, there is a problem that the number of parts is large and it is difficult to reduce the cost and the size.
In order to solve this problem, an apparatus has been proposed in which one scanning member is used for both the left eye and the right eye. For example, in a video display device proposed in Japanese Patent Application Laid-Open No. 6-308408, separate scanning surfaces of one polygon mirror are used separately for the left eye and the right eye, so that one scanning operation is performed for both the left and right eyes. The members are being shared.

[0003]

However, when a polygon mirror is used as a scanning member, it is difficult to make the whole apparatus compact because the polygon mirror itself is large. Further, accurate polishing of a large number of reflecting surfaces is required for the production of a polygon mirror, but a higher working accuracy is required to synchronize left and right images.

The present invention has been made in view of such a situation, and an object of the present invention is to provide a compact and inexpensive image display device by achieving sharing of a scanning member with a simple configuration. I do.

[0005]

In order to achieve the above object, an image display apparatus according to the present invention comprises at least one light beam from a light source for a left eye and at least one light beam from a light source for a right eye.
An image display device configured to allow a two-dimensional image to be observed by both the left and right eyes by being guided to the eyes while scanning in the left and right directions. A scanning mirror that simultaneously scans the two light beams by deflecting the light beam from the light source for use and simultaneously oscillating the other reflection surface to deflect the light beam from the light source for the right eye. It is characterized by.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a video display device embodying the present invention will be described with reference to the drawings. Note that the same or corresponding portions in the embodiments are denoted by the same reference numerals, and redundant description will be appropriately omitted.

<< First Embodiment (FIGS. 1 and 2) >> FIG. 1 is a perspective view showing a schematic configuration of a video display device according to a first embodiment, and FIG. FIG. 5 is a front view showing a state viewed from the right eye ER side. This video display device
Light source 1L, 1R for left eye and right eye, collimator lens 2
L, 2R, half mirrors 3L, 3R, vertical scanning mirrors 4L, 4R, horizontal scanning mirror 5, and half mirror 6.
L, 6R and eyepiece mirrors 7L, 7R. Each of the left-eye and right-eye light sources 1L and 1R is composed of a modulatable LD (laser diode).

The vertical scanning mirrors 4L and 4R comprise a plane half mirror, and the horizontal scanning mirror 5 comprises a plane double-sided mirror. The vertical and horizontal scanning mirrors 4L and 4R;
This is a galvanometer mirror that scans a light beam by vibrating and rotating. The horizontal scanning mirror 5 oscillates and rotates so that one reflection surface deflects the light beam from the left-eye light source 1L and the other reflection surface deflects the light beam from the right-eye light source 1R. As a result, the two light beams are horizontally scanned simultaneously. The light beam from the light source 1L for the left eye and the light beam from the light source 1R for the right eye are guided to the eyes EL and ER while being scanned in the horizontal and vertical directions, respectively, as described below. Is observed as a two-dimensional image.

The light beam emitted from the left eye light source 1L is converged by the collimator lens 2L and then enters the half mirror 3L. The light beam reflected by the reflection mirror 3L is transmitted through the vertical scanning mirror 4L and then reflected by one of the reflection surfaces of the horizontal scanning mirror 5. The light beam reflected by the horizontal scanning mirror 5 is reflected by the vertical scanning mirror 4L and then reflected by the horizontal scanning mirror 5 again. At this point, the horizontal / vertical scanning of the light beam forming the two-dimensional image for the left eye is completed. The light beam reflected by the horizontal scanning mirror 5 passes through the vertical scanning mirror 4L,
After passing through L, the light enters the half mirror 6L. The light beam reflected by the half mirror 6L is reflected by the eyepiece mirror 7L formed of a concave mirror, and then passes through the half mirror 6L to reach the left eye EL. The left eye EL observes a virtual image of the two-dimensional image projected by the eyepiece mirror 7L.

The light beam emitted from the right eye light source 1R is converged by a collimator lens 2R and then enters a half mirror 3R. The light beam reflected by the reflection mirror 3R is transmitted through the vertical scanning mirror 4R and then reflected by the other reflection surface of the horizontal scanning mirror 5 (the back surface of the surface that reflects the light beam from the left-eye light source 1L). . Horizontal scanning mirror 5
Are reflected by the vertical scanning mirror 4R and then again by the horizontal scanning mirror 5. At this point, the horizontal and vertical scanning of the light beam forming the two-dimensional image for the right eye is completed. The light beam reflected by the horizontal scanning mirror 5 passes through the vertical scanning mirror 4R, and passes through the half mirror 3
After passing through R, the light enters the half mirror 6R. The light beam reflected by the half mirror 6R is reflected by the eyepiece mirror 7R formed of a concave mirror, and then passes through the half mirror 6R to reach the right eye ER. The right eye ER observes a virtual image of the two-dimensional image projected by the eyepiece mirror 7R.

The vertical scanning of each light beam is performed by a vertical scanning mirror 4.
The horizontal scanning of each light beam is performed by two reflections on the horizontal scanning mirror 5 while the reflection is performed by one reflection at L and 4R. Therefore, the deflection angle of horizontal scanning is doubled as compared with the case where a light beam is reflected by the horizontal scanning mirror 5 once, and it is possible to advantageously perform a wide viewing angle and high-speed scanning. .

Since the horizontal scanning mirror 5 composed of a double-sided mirror is used commonly for horizontal scanning of the left and right eyes, it is possible to reduce the size and cost and to easily synchronize the left and right images. Further, since the scanning of the two light beams is performed by one scanning member, there is no interference between mirrors, and thus a wide viewing angle can be achieved. In order to suppress ghost due to multiple reflections, the vertical scanning mirror 4
It is desirable to insert a polarizing plate and a cholesteric liquid crystal between the L and 4R and the horizontal scanning mirror 5. In the first embodiment, the double-sided mirror 5 is used for both horizontal scanning for the left eye and horizontal scanning for the right eye, but the double-sided mirror 5 is used for vertical scanning for the left eye and for the right eye. It may be configured to be shared with vertical scanning.

<< Second Embodiment (FIG. 3) >> FIG.
1 is a plan view illustrating a schematic configuration of a video display device according to an embodiment. This image display device includes a left-eye light source 1 and a right-eye light source 1.
L, 1R, collimator lenses 2L, 2R, horizontal scanning mirror 8, relay lenses 9L, 9R, vertical scanning mirrors 10L, 10R, and eyepiece optical systems 11L, 11R.

The horizontal scanning mirror 8 is a flat double-sided mirror,
The vertical scanning mirrors 10L and 10R are each composed of a flat one-sided mirror, and the horizontal and vertical scanning mirrors 8;
R is a galvanomirror that scans a light beam by vibrating and rotating. The horizontal scanning mirror 8 oscillates and rotates so that one reflecting surface deflects the light beam from the left-eye light source 1L and the other reflecting surface deflects the light beam from the right-eye light source 1R. As a result, the two light beams are horizontally scanned simultaneously. The general arrangement is such that the horizontal scanning mirror 8 is located at the entrance pupil of the relay lenses 9L and 9R, and the vertical scanning mirrors 10L and 10R are located at the exit pupils of the relay lenses 9L and 9R. The light beam from the light source 1L for the left eye and the light beam from the light source 1R for the right eye are guided to the eyes EL and ER while being scanned in the horizontal and vertical directions, respectively, as described below. Is observed as a two-dimensional image.

The light beam emitted from the left-eye light source 1L is converged by the collimator lens 2L and then reflected by one of the reflection surfaces of the horizontal scanning mirror 8. Horizontal scanning mirror 8
Are reflected by the relay lens 9L at the position of the vertical scanning mirror 10L, and are reflected by the vertical scanning mirror 10L. At this point, the horizontal / vertical scanning of the light beam forming the two-dimensional image for the left eye is completed. The light beam reflected by the vertical scanning mirror 10L reaches the left eye EL after passing through the eyepiece optical system 11L. The left eye EL observes a virtual image of the two-dimensional image projected by the eyepiece optical system 11L.

The light beam emitted from the right eye light source 1R is converged by the collimator lens 2R, and then the other reflection surface of the horizontal scanning mirror 8 (the back surface of the surface that reflects the light beam from the left eye light source 1L) ). The light beam reflected by the horizontal scanning mirror 8 is collected by the relay lens 9R at the position of the vertical scanning mirror 10R, and
Is reflected by At this point, the horizontal and vertical scanning of the light beam forming the two-dimensional image for the right eye is completed. The light beam reflected by the vertical scanning mirror 10R is transmitted to the eyepiece optical system 11R.
, And reaches the right eye ER. The right eye ER observes a virtual image of the two-dimensional image projected by the eyepiece optical system 11R.

Since the horizontal scanning mirror 8 composed of one double-sided mirror is used commonly for horizontal scanning of both the left and right eyes, the same effects as in the first embodiment can be obtained. Further, since the light is arranged so as to be obliquely incident on the horizontal scanning mirror 8, the optical paths of the incident light and the emitted light do not overlap, and there is also an effect that a half mirror or a mirror for bending the optical path is not required. Note that a configuration in which the double-sided mirror 8 is shared for the left and right vertical scanning may be adopted.

<< Third Embodiment (FIG. 4) >> FIG.
1 is a plan view illustrating a schematic configuration of a video display device according to an embodiment. This image display device includes a left-eye light source 1 and a right-eye light source 1.
L, 1R, collimator lenses 2L, 2R, horizontal scanning mirror 12, vertical scanning mirror 13, relay mirror 1
4L and 14R, and eyepiece optical systems 11L and 11R.

Horizontal scanning mirror 12, vertical scanning mirror 13
Both are galvano mirrors, each of which is composed of a planar double-sided mirror and scans a light beam by vibrating and rotating. The horizontal scanning mirrors 12 and 13 oscillate and rotate such that one reflecting surface deflects the light beam from the left-eye light source 1L and the other reflecting surface deflects the light beam from the right-eye light source 1R. . As a result, two light beams are simultaneously scanned horizontally and vertically. Also, the relay mirror 14L, 1
4R is composed of an eccentric reflecting mirror (elliptical mirror), the horizontal scanning mirror 12 is located at the entrance pupil of the relay mirrors 14L and 14R, and the vertical scanning mirror 13 is a relay mirror 14
The general arrangement is such that it is located at the exit pupil of L, 14R. Light beam from left eye light source 1L and right eye light source 1R
Are guided to the eyes EL and ER while being scanned in the horizontal and vertical directions, respectively, as described below, and are observed as a two-dimensional image by the left and right eyes.

The light beam emitted from the light source 1L for the left eye is converged by the collimator lens 2L and then reflected by one of the reflection surfaces of the horizontal scanning mirror 12. The light beam reflected by the horizontal scanning mirror 12 is gathered at the position of the vertical scanning mirror 13 by the relay mirror 14L, and
Is reflected by one of the reflection surfaces. At this point, 2 for the left eye
The horizontal and vertical scanning of the light beam forming the two-dimensional image is completed. The light beam reflected by the vertical scanning mirror 13 reaches the left eye EL after passing through the eyepiece optical system 11L. The left eye EL observes a virtual image of the two-dimensional image projected by the eyepiece optical system 11L.

The light beam emitted from the light source 1R for the right eye is converged by the collimator lens 2R, and then the other reflection surface of the horizontal scanning mirror 12 (the back surface of the surface for reflecting the light beam from the light source 1L for the left eye) ). The light beam reflected by the horizontal scanning mirror 12 is gathered at the position of the vertical scanning mirror 13 by the relay mirror 14R, and
3 is reflected by the other reflection surface (the back surface of the surface that reflects the light beam from the left-eye light source 1L). At this point, the horizontal and vertical scanning of the light beam forming the two-dimensional image for the right eye is completed. The light beam reflected by the vertical scanning mirror 13 is
After passing through the eyepiece optical system 11R, it reaches the right eye ER.
The right eye ER observes a virtual image of the two-dimensional image projected by the eyepiece optical system 11R.

Horizontal scanning mirror 12 and vertical scanning mirror 13
Are both composed of double-sided mirrors, and are shared by both the left and right eyes for horizontal scanning and vertical scanning. Therefore, the same effect as in the first embodiment can be obtained for both horizontal scanning and vertical scanning. Further, since the light is arranged so as to be obliquely incident on the horizontal scanning mirror 12, the optical paths of the incident light and the emitted light do not overlap, and there is also an effect that a half mirror or a mirror for bending the optical path is not required. Note that a configuration may be adopted in which the double-sided mirror 12 is shared for left and right vertical scanning and the double-sided mirror 13 is shared for left and right horizontal scanning.

The relay mirrors 14L and 14R not only have a function of bending the optical path from the horizontal scanning mirror 12 to the vertical scanning mirror 13 to relay the pupil position, but also have a function of increasing the degree of freedom of arrangement by their power. That is, the horizontal scanning mirror 12 and the vertical scanning mirror 13 are brought closer to each other, thereby contributing to achieving compactness. Also, the power of the relay mirrors 14L and 14R is
It also acts to share the power of L, 11R.

<< Fourth Embodiment (FIGS. 5 and 6) >> FIG. 5 is a perspective view showing a schematic configuration of a video display device according to a fourth embodiment, and FIG. It is a top view showing the state where optical composition was seen from the upper part. This image display device includes light sources 1L and 1R for the left and right eyes, and a collimator lens 2
L, 2R, horizontal scanning mirror 15, and vertical scanning mirror 1
6L and 16R, half mirrors 6L and 6R, and eyepiece mirrors 7L and 7R.

Horizontal scanning mirror 15, vertical scanning mirror 16
Both L and 16R are galvano mirrors which are formed of flat single-sided mirrors and scan light beams by vibrating and rotating. The horizontal scanning mirror 15 vibrates and rotates so as to deflect the left-eye light beam and the right-eye light beam in directions different from each other on the same reflection surface. As a result, the two light beams are horizontally scanned simultaneously. The light beam from the light source 1L for the left eye and the light beam from the light source 1R for the right eye are guided to the eyes EL and ER while being scanned in the horizontal and vertical directions, respectively, as described below. Is observed as a two-dimensional image.

The light beam emitted from the left-eye light source 1L proceeds obliquely downward, is converged by the collimator lens 2L, and is reflected by the reflection surface of the horizontal scanning mirror 15. The light beam reflected by the horizontal scanning mirror 15 is reflected by the vertical scanning mirror 16L. At this point, the horizontal / vertical scanning of the light beam forming the two-dimensional image for the left eye is completed. The light beam reflected by the vertical scanning mirror 16L is reflected by the half mirror 6L, and is connected to the eyepiece mirror 7 composed of a concave mirror.
After being reflected by L, the light passes through the half mirror 6L and passes through the left eye E
Reach L. The left eye EL observes a virtual image of the two-dimensional image projected by the eyepiece mirror 7L.

The light beam emitted from the right-eye light source 1R travels obliquely downward, is converged by the collimator lens 2R, and is reflected by the reflection surface of the horizontal scanning mirror 15. The light beam reflected by the horizontal scanning mirror 15 is reflected by the vertical scanning mirror 16R. At this point, the horizontal and vertical scanning of the light beam forming the two-dimensional image for the right eye is completed. The light beam reflected by the vertical scanning mirror 16R is reflected by the half mirror 6R, and is connected to the eyepiece mirror 7 composed of a concave mirror.
After being reflected by R, the light passes through the half mirror 6R and passes through the right eye E
Reach R. The right eye ER observes a virtual image of the two-dimensional image projected by the eyepiece mirror 7R.

Since one horizontal scanning mirror 15 is used for horizontal scanning of the left and right eyes, the same effect as that of the first embodiment can be obtained. Furthermore, since the light is arranged so as to be obliquely incident on the horizontal scanning mirror 15, the optical paths of the incident light and the emitted light do not overlap, and there is an effect that a half mirror or a mirror for bending the optical path is not required. Since only one reflecting surface is required, manufacture of the mirror is easy, and a mirror driving device can be arranged on the back side of the mirror. Therefore, it is possible to reduce the size of the entire scanning device including the mirror driving device. The single-sided mirror 1
A configuration in which 5 is used for both left and right vertical scanning may be adopted.

[0029]

As described above, according to the present invention, the sharing of the scanning member can be achieved with a simple configuration, so that a compact and inexpensive image display device can be realized.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing a first embodiment.

FIG. 2 is a front view schematically showing the first embodiment.

FIG. 3 is a plan view schematically showing a second embodiment.

FIG. 4 is a plan view schematically showing a third embodiment.

FIG. 5 is a perspective view schematically showing a fourth embodiment.

FIG. 6 is a plan view schematically showing a main part of a fourth embodiment.

[Explanation of symbols]

 1L, 1R Light source 4L, 4R Vertical scanning mirror 5 Horizontal scanning mirror 8 Horizontal scanning mirror 10L, 10R Vertical scanning mirror 12 Horizontal scanning mirror 13 Vertical scanning mirror 15 Horizontal scanning mirror 16L, 16R Vertical scanning Mirror EL… Left eye ER… Right eye

Claims (1)

[Claims] 1. A light beam from a light source for a left eye and a light beam from a light source for a right eye are guided to an eye while scanning in at least one direction so that a two-dimensional image can be observed by both the left and right eyes. An image display device comprising: a two-sided flat mirror; one reflecting surface deflects a light beam from the left-eye light source and the other reflecting surface simultaneously deflects light from the right-eye light source. An image display device, comprising: a scanning mirror for simultaneously scanning the two light beams by vibrating so as to deflect the beams.