JPH06235885A - Stereoscopic picture display device - Google Patents

Abstract

PURPOSE:To provide a stereoscopic picture display device adequate to being used in a virtual actuality feeling device, etc. CONSTITUTION:A picture display unit 1 or the position of an optical system 2 enlarging and image-forming a picture displayed on the unit 1 as a virtual picture is changed by a controlling and driving part 4 as the line of sight direction of both right and left eyes of an observer is changed (or eye movement), so that the position of the virtual image is aligned with a congestion position obtained from the change of the line of sight direction (or eye movement).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stereoscopic image display device suitable for use in a virtual reality device or the like, and more particularly to a stereoscopic image display device using a magnifying optical system such as an eyepiece type or a head mounted type.

[0002]

2. Description of the Related Art An example of a conventional stereoscopic image display device of this type is shown in FIG. In FIG. 4, reference numeral 1 denotes a pair of image displays, which can display a stereoscopic image based on the left and right binocular parallax images, and are arranged immediately in front of the left and right eyes for the left eye and the right eye. The image displayed on the display 1 is magnified and imaged as a virtual image on a display surface (hereinafter referred to as A surface) assumed in space by a pair of convex lenses 2 as a magnifying optical system. As a result, unlike the case where a stereoscopic image is displayed in a limited area like a movie screen, stereoscopic images are projected in the entire field of view, and it is possible to experience virtual reality. It has been used in and theme parks.

[0003]

In the conventional stereoscopic image display device described with reference to FIG. 4, a pair of image display 1 and a pair of convex lenses 2 are fixedly arranged, and the positional relations in the optical axis direction are provided. Since it is fixed, the virtual image is always A
The image is magnified on the surface.

On the other hand, the lines of sight of the left and right eyes of the observer are directed toward the target display image by the vergence movement, and the position where the lines of sight of both eyes are tolerated is the eye vergence position (hereinafter simply referred to as the vergence position).
Since this position changes in the depth direction, the perspective is judged and a three-dimensional effect is felt. Therefore, even if this convergence position is in the center of the image displayed on the display 1,
Depending on the subject to be projected, it may happen that the position is on the same A plane as the virtual image, as shown by the ● mark, or it may be at the position shown by the X mark behind this A face, depending on the contents of the displayed image. It is fixed.

Even in the real space in which we live, the perspective is determined by the position of convergence, but the focus adjustment of the eye to the point to be viewed is automatically linked with the change of the position of convergence. It is being appreciated. However, although the vergence position changes depending on the contents of the displayed image as in the conventional stereoscopic image display device, if the image forming position is fixed, it is extremely unnatural and imposes a visual burden on the observer.

In particular, in the case of a See-Through display device for optically superimposing a displayed virtual three-dimensional image (image) and an actual object, the image forming position of the image showing the same perspective and the actual object are displayed. Since the positions are different in depth, the visual burden is further increased. To solve this problem, we detect the gazing point on the screen to make it as close as possible to the state of real space to ease the visual burden, and stereoscopic image display with active image processing that blurs the image other than the target point. A device is also considered, but this method is not easy because it is necessary to analyze the depth of the displayed image.

It is an object of the present invention to provide a stereoscopic image display device capable of displaying a stereoscopic image closer to real space vision so as to reduce visual fatigue and reduce eye fatigue. .

[0008]

In order to achieve the above object, a stereoscopic image display device of the present invention is for a left eye and a right eye which are respectively arranged close to the left and right eyes of an observer to form a stereoscopic image. A pair of image display means for displaying images respectively and a pair of magnifying optical systems for magnifying and forming the images displayed on the means as virtual images in space are provided, and the left and right eyes of the observer with respect to the virtual images. In the stereoscopic image display device to generate a stereoscopic effect, a line-of-sight direction detector that detects the line-of-sight directions of the left and right eyes of the observer, and the eye convergence position based on the line-of-sight direction detected by the detector. And a control drive means for controlling and driving the pair of image display means and / or the pair of magnifying optical systems so that the virtual image is formed at the determined eye convergence position. To do.

[0009]

In order to eliminate the visual burden on the eyes of the observer, the present invention automatically adjusts the image forming position of the display image according to the change of the vergence positions of the left and right eyes, and makes the image forming position coincide with the vergence position. This will be described with reference to FIGS. 1 and 2.

FIG. 1 is a line showing a depth position and a lateral position (size) of a display image, and a convergence position and a position of a stereoscopic image when the image forming position of the display image is changed in the stereoscopic image display device of the present invention. It is a figure, and shows the position of the eye as the distance from the origin. The vergence position is z in depth
At the position indicated by ● at the position
At the same time, the image forming plane of the virtual image also coincides with the A surface, and in this case, the convergence position and the image forming position coincide with each other, so that no strain is applied to the eye. Next, from this state, it is assumed that only the vergence position is moved to the position z'in the depth direction (hereinafter referred to as the B surface) to the position indicated by the cross mark. The image plane of the virtual image is still on the A plane,
Since the vergence position and the image formation position do not coincide with each other, a burden is placed on the eye.

Therefore, with the convex lens 2 shown in the figure fixed, the image display 1 is moved from the initial position d to d ′ so that the image forming plane of the virtual image coincides with the B plane, and the convergence position and virtual image of the virtual image shown by x are formed. Try to match the positions. This eliminates strain on the eyes. At this time, if the lateral position (size) of the left and right binocular parallax images is changed from 1 to 1 ', then l' / l = z '/ z is established in relation to the depth positions z and z'.

FIG. 2 is a diagram showing the depth position and the vertical position (size) of the displayed image when the position of the image display is changed. Here, the eye position is taken as the origin and the distance from it is shown. , The same reference numerals as used in FIG. 1 are used.
As shown in the figure, if the image display 1 is changed from the position d to the position d ', the image forming point of the virtual image is changed from the A surface to the B surface as shown by the solid line and the broken line, respectively. . Assuming that the position of the eye is at the position of the focal point of the convex lens 2, h '/ h = z' / z, which matches the relationship between the depth position and the lateral position (size) derived in FIG. As for the position of the eye, it does not necessarily have to be at the focal position of the convex lens 2 because it may be at a position on the opposite side of the image display device 1 with the convex lens 2 interposed therebetween.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to actually change the position of the image display and match the position of the displayed image with the convergence position based on the principle of the present invention described above, the following procedure is performed. One embodiment of the present invention is shown in FIG.

In FIG. 3, the image display 1 and the convex lens 2 are shown.
The planes A and B showing the depth position are the same as those in FIGS. In this example, in order to automatically adjust the image forming position of the virtual image to the vergence position, a pair of left and right line-of-sight direction detectors 3 for detecting the line-of-sight directions of the left and right eyes are arranged near the eyes of the observer. The detection of the line-of-sight direction (for example, the detection of the angle θ in FIG. 1) is nothing but the detection of the eye movement which causes the vergence action.

As the line-of-sight direction detector 3, for example, for the left and right eyes, near-infrared light is applied to the eyeball and the reflected light is detected by photodetectors arranged on both sides of the black eye, and the boundary between the black eye and the white eye is detected. It is conceivable to use a device that detects changes in the amount of light and detects the direction of the line of sight or eye movement. As another method, the eyeball is irradiated with spot light and the reflected light is captured by a two-dimensional optical position detector, or the eye movement is detected by obtaining position information of the black eye using a micro television camera. You can

The convergence position is calculated based on the line-of-sight direction or eye movement detected by the line-of-sight direction detector 3, and the position for moving the position of the image display 1 based on the calculation result is the control drive shown in the figure. Part 4.

The control drive unit 4 calculates the positions d and d'of the image display device 1 corresponding to the vergence positions z and z ', but this is because the visual lines of the left and right eyes detected by the visual line direction detector 3 are calculated. If the angle of intersection, that is, the angle of convergence is θ (radian) (see FIG. 1), the following relationship is established. First, the convergence position z is

It is represented by z = I / θ, where I is the pupillary distance (about 65
mm). Along with this, when the origin is the eye position, the reference position of the image display is d, the focal length of the convex lens 2 is f, and the distance from the eye to the convex lens 2 is k, the relationship between them is

## EQU2 ## It is represented by d-k = 1 / (1 / (z-k) + 1 / f). From this point, the variable range of the position d of the image display is at most f (focal length of the convex lens 2).

With respect to the reference position d of the image display 1 and the reference position z of the vergence position expressed by the above formula, a new position d ', vergence angle θ', vergence position of the image display 1 after the position change. The relationship with z'is expressed by the following equation using the above parameters.

## EQU3 ## z '= I / .theta.' D'-k = 1 / (1 / (z'-k) + 1 / f)

In the above description, the position of the image display device 1 is changed to match the image formation position of the virtual image with the convergence position, but this is performed even if the position of the convex lens 2 is changed. Needless to say, the positions of both the image display device 1 and the convex lens 2 may be changed.

Further, instead of the convex lens, another optical system, for example, a concave mirror for magnifying an image may be used. In this case, in order to prevent the image display and the displayed image from overlapping with each other on the line of sight, For example, a semi-transparent mirror inclined 45 degrees with respect to the optical axis of the concave mirror is placed in front of the concave mirror, and the image display is arranged at a position orthogonal to the optical axis of the concave mirror.

[0021]

As described above, according to the present invention, the position of the image display 1 (or the convex lens 2) is changed in accordance with the change in the line-of-sight direction of the left and right eyes of the observer (or eye movement). By matching the image formation position of the display image with the vergence position, it is possible to match the vergence position with the virtual image position of the stereoscopic image, that is, the focus adjustment position of the eye lens while maintaining the positional relationship between the stereoscopic images. In this way, by making the image formation position of the display image coincide with the binocular vergence position and bringing it into a state close to real space vision, it is possible to obtain the effect of eliminating the visual burden such as fatigue.

[Brief description of drawings]

FIG. 1 shows a depth position and a lateral position (size) of a display image, and a convergence position and a position of a stereoscopic image when the image forming position of the display image is changed in the stereoscopic image display device of the present invention. It is a diagram.

FIG. 2 is a diagram showing a depth position and a vertical position (size) of a display image when the position of the image display is changed in the stereoscopic image display device of the present invention.

FIG. 3 is a perspective view showing an embodiment of a stereoscopic image display device of the present invention.

FIG. 4 is a perspective view showing an example of a conventional stereoscopic image display device.

[Explanation of symbols]

 1 Image display 2 Convex lens 3 Line-of-sight direction detector 4 Control drive unit

Claims (1)

[Claims] 1. A pair of image display means for displaying left-eye and right-eye images, which are respectively arranged close to the left and right eyes of an observer and constitute a stereoscopic image, and a pair of image display means respectively displayed on the means. And a pair of magnifying optical systems for magnifying and forming a virtual image in a space as a virtual image to generate a stereoscopic effect on the virtual image on both the left and right eyes of the observer. A line-of-sight direction detector that detects the line-of-sight directions of both eyes, and determines the eyeball convergence position based on the line-of-sight direction detected by the detector, so that the virtual image is formed at the determined eyeball convergence position. A stereoscopic image display device comprising: a pair of image display means and / or a control drive means for controlling and driving the pair of magnifying optical systems.