JPH11326814A - Head-mounted display device and method of producing magnified picture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a longitudinal thickness smaller while keeping the size of a generated magnified picture as it is. SOLUTION: A picture display part 1 has a height shorter than that of the aspect ratio (height to width ratio) of a picture actually shown to a user. A toric lens 2 is arranged ahead of a display screen of this picture display part 1. A toric half mirror 3 is arranged in the advancing direction of the light transmitted through the toric lens 2. The toric half mirror 3 is arranged so as to reflect the light from the picture display part 1 to ahead of the user's visual line. A concave mirror 4 is arranged in the advancing direction of the light reflected by the toric half-mirror 3. The concave mirror 4 is positively paired with the toric half mirror 3. Thus, a picture 5 displayed on the picture display part 1 is expanded in the direction of the height by an anamorphic optical system before magnified, and becomes a magnified virtual image 6 visible to the user.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a head-mounted display device used by being mounted on a head and an enlarged image generating method for generating an enlarged image to be displayed on such a head-mounted display device. In particular, the present invention relates to a head-mounted display device with improved portability and an enlarged image display method for generating an enlarged image to be displayed on the head-mounted display device with high portability.

[0002]

2. Description of the Related Art In recent years, an enlarged virtual image of an image input from a computer or a video device has been observed, and the
A head-mounted display device has been put on the market that allows the user to experience a 50-inch powerful screen m ahead. Such a head-mounted display device is basically composed of a ring and a display unit. A pad is provided on the ring, and the pad is pressed against the user's forehead, and the ring is hung on the head, so that the user can wear it as if wearing glasses.

FIG. 5 is a diagram showing a schematic configuration of a conventional head-mounted display device. A liquid crystal display panel (LCD: Liquid Crystal Display) 41 is provided on the head-mounted display device 40.
The LCD 41 displays an image sent from a video device or the like. Below the LCD 41, a half mirror 42 is provided. The half mirror 42 is LC
The light emitted from D41 is arranged so as to be reflected forward of the user's line of sight. On the optical path of the light reflected from the half mirror 42, a concave mirror 43 is provided to face the half mirror 42.

The LC of such a head mounted display device 40
When an image is displayed on D41, the image is reflected by the half mirror 42 toward the front of the user. The image reflected by the half mirror 42 is reflected by the concave mirror 43 and returned to the half mirror 42 again. By being reflected by the concave mirror 43, an enlarged virtual image of the image displayed on the LCD 41 is generated. The enlarged virtual image returned from the concave mirror 43 transmits through the half mirror 42 and forms an image on the retina of the user's eye.

By using such a head-mounted display device, a user can enjoy a large-screen image without taking up space.

[0006]

However, the conventional head mounted display has a large thickness in the front-rear direction when worn, and cannot be said to be sufficiently portable. In order to reduce the thickness of the head mounted display, it is necessary to reduce the size of the liquid crystal display panel used for the head mounted display. However, reducing the size of the liquid crystal display panel is not preferable because the size of the generated enlarged virtual image also decreases.

The present invention has been made in view of such a point, and the size of an enlarged image to be generated is not changed.
An object of the present invention is to provide a head-mounted display device capable of reducing the thickness in the front-rear direction.

Another object of the present invention is to provide an enlarged image display method for displaying an enlarged image of a thinned head-mounted display device at the same size as before the thickness reduction. That is.

[0009]

According to the present invention, in order to solve the above-mentioned problems, in a head-mounted display device used by being mounted on a head, an image display unit for displaying an image, and the image display unit A toric lens arranged in front of the surface displaying the image of the image display unit, and correcting the image size of the image display unit,
A toric half mirror arranged to reflect the light transmitted through the toric lens, and a concave mirror arranged on the optical path of the light reflected by the toric half mirror, facing the toric half mirror, There is provided a head-mounted display device having

According to such a head mounted display device,
When an image is displayed on the image display unit, light of the image is output through the toric lens. The image transmitted through the toric lens is corrected in image size and reflected by the toric half mirror. The reflected light is reflected by the concave mirror and returned to the toric half mirror. On this occasion,
An enlarged virtual image of the image whose size has been corrected is generated. The image reflected from the concave mirror is transmitted through the toric half mirror and output. The output image is a virtual image whose screen size has been corrected and enlarged.

According to another aspect of the present invention, there is provided an enlarged image generating method for generating an enlarged image to be displayed on a head mounted display used by being mounted on a head. The aspect ratio of the displayed image is corrected by a toric lens, the corrected image corrected by the toric lens is reflected by a toric half mirror, and the corrected image reflected by the toric half mirror is reflected by the concave mirror to the half mirror unit. By reflecting toward
An enlarged image generation method is provided, wherein an enlarged virtual image of the corrected image is generated. According to such an enlarged image generation method, the aspect ratio of the image displayed on the image display unit is corrected by the toric lens, and the corrected image is obtained. The corrected image is reflected by the toric half mirror. The reflected virtual image is reflected by the concave mirror to generate an enlarged virtual image. By visually recognizing the enlarged virtual image, the user can see the enlarged image whose aspect ratio has been corrected.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram illustrating the principle of the present invention.
The head-mounted display device of the present invention employs an anamorphic optical system (an optical system that generates images having different magnifications in the vertical and horizontal directions on the image plane).

The length of the image display unit 1 in the vertical direction is shorter than the aspect ratio (aspect ratio) of the image actually shown to the user (in the example of FIG. There). A toric lens (Toriclens) 2 is arranged in front of the display screen of the image display unit 1. The back surface of the toric lens 2 (the surface facing the image display unit 1 is a front surface) is an annular surface that can cause refraction such that the image displayed by the image display unit 1 is elongated in the vertical direction. In the traveling direction of the light transmitted through the toric lens 2,
A toric half mirror 3 is provided. The shape of the surface of the toric half mirror 3 (the surface facing the image display unit 1 and the toric lens 2) is an annular surface (a toric surface). The toric half mirror 3 is arranged so as to reflect light from the image display unit 1 forward of the user's line of sight. A concave mirror 4 is arranged in the traveling direction of the light reflected by the toric half mirror 3. The concave mirror 4 faces the toric half mirror 3.
The focal length of the concave mirror 4 is longer than the optical path length from the image display unit 1 to the concave mirror 4. Therefore, the image display unit 1
Is reflected by the concave mirror 4, an enlarged virtual image is generated.

According to the head mounted display device having such an optical system, the image 5 displayed on the image display unit 1 is transmitted through the toric lens 2 and reflected by the toric half mirror 3. As a result, the aspect ratio (21:40) of the image 5 that has been shortened in the vertical direction is returned to the aspect ratio (3: 4) of the image that is actually to be shown to the user. The light reflected by the toric half mirror 3 travels toward the concave lens 4 and is reflected by the concave lens 4. Thus, an enlarged virtual image 6 of the image 5 is generated. The light reflected by the concave lens 4 passes through the toric half mirror 3 and becomes emitted light. The user can visually recognize the enlarged virtual image 6 by looking at the emitted light. The enlarged image viewed by the user is longer than the image 5 displayed on the image display unit 1 in the vertical direction.

As described above, by generating the enlarged virtual image of the image display device using the toric lens, it is possible to reduce the length of the image display unit in the front-rear direction and convert the aspect ratio to generate the enlarged virtual image. it can. As a result, it is possible to use the image display unit 1 having a shorter length in the vertical direction than before, and it is possible to reduce the thickness of the head mounted display device itself. In addition, the size of the enlarged virtual image 6 visually recognized by the user remains the same.

The structure of the optical head mounted display device shown in FIG. 1 will be specifically described below. FIG.
1 is a schematic sectional view of a head-mounted display device according to the present invention. FIG.
In the head-mounted display device 10 using a toric lens of the present invention, a backlight 11 is provided to illuminate a liquid crystal display panel (LCD) 12 provided on the left and right from above. Behind LCD12, LCD12
Is provided, and a toric half mirror 14 for reflecting the display image on the LCD 12 is provided ahead of the toric lens 13. The toric half mirror 14 is arranged at an angle such that the light from the LCD 12 is reflected forward of the user's line of sight. A concave half mirror 15 is provided in the traveling direction of the light reflected by the toric half mirror 14. The concave half mirror 15 faces the toric half mirror 14. A liquid crystal shutter 16 is provided ahead of the concave half mirror 15 as viewed from the user. The transparency of the liquid crystal shutter 16 can be adjusted, and the amount of light incident from the outside of the head-mounted display device 10 can be freely changed.

In such a head-mounted display device 10, an image transmitted from a video device or the like is transmitted to the LCD 1.
2 is displayed. The LCD provided on the left side of the LCD 12 displays an image for the left eye, and the LCD provided on the right side displays an image for the right eye. Light of an image displayed on the LCD 12 irradiates a toric half mirror 14 via a toric lens 13. The image is reflected by the toric half mirror 14, further expanded and reflected by the concave half mirror 15, and reaches the user's eyes 21 again through the toric half mirror 14. Thereby, the user can visually recognize the enlarged virtual image projected on the virtual screen 22.

As described above, the user can wear the head-mounted display device and view a large-screen image displayed on the screen 22. The size of the screen 22 seen by the eyes 21 is LCD
Although the image is felt by the ratio of the viewing angle when the 12 images enter the eye 21 and the total viewing angle seen by the eyes, in this example, since the viewing angle is set to 30 °, a virtual image of 2 m is obtained. In terms of distance, you are looking at a large 52-inch screen.

FIG. 3 is a diagram showing the shape of the toric lens. As shown in the figure, the toric lens 13 is formed of an annular surface having different curvatures in the vertical and horizontal directions (the vertical curvature is “A” and the horizontal curvature is “B”). The surface shape of the toric half mirror 14 is the same. The aspherical surface (Aspherical Surface) of the toric lens 13 and the toric half mirror 14 may be a cylindrical surface, but by performing a curvature correction as shown in FIG.
Performance can be improved. The toric lens 13 and the toric half mirror 14 have a function of relatively canceling out distortion due to an aspheric surface.

Here, for example, the length of the LCD 12 in the front-rear direction is reduced to 0.7 L with respect to the conventional length L, and the length is reduced to the toric lens 13 and the toric halfler 14.
When the aspect is converted and restored, the vertical dimension of the LCD 12 can be reduced to 70% of the conventional size. In addition, the thickness of the head-mounted display device 10 itself can be reduced. In addition, the user can view the same large-screen video as before.

Next, a circuit configuration of a head mounted display device using a toric lens will be described. FIG. 4 is a block diagram illustrating a circuit configuration of the head-mounted display device. The circuit unit 17 of the head-mounted display device 10 receives an input of a video signal from a video device or the like, and based on the video signal, the LCD 1
2 is controlled. The circuit unit 17 includes a video processing unit 17a and a control unit 17b. The video processing unit 17a converts a video signal input from the outside into the LCD 12
Is converted to image information that can be displayed on the LCD 12 and sent to the LCD 12. L
The image information to be sent to the CD 12 is such that the displayed image has three primary colors (red,
Green, blue). The control unit 17b is connected to the video processing unit 17a, and generates a control signal and a timing signal necessary for displaying an image processed by the video processing unit 17a. Specifically, it is a horizontal synchronization signal or a vertical synchronization signal. These control signals are sent to the video processing unit 1 once.
7a and output to the LCD 12 together with the image information.

In such a circuit, when a video signal is input from a VTR or the like, the video processing
The data is converted into image information in a format that can be displayed in D12. At the same time, a control signal required for image display is sent to the video processing unit 17a by the control unit 17b. The video processing unit 17 a
The video information expressed in (red), G (green), and B (blue) is transmitted to the LCD 12 together with the synchronization signal transmitted from the control unit 17b. The LCD 12 displays an image on the screen based on the image information sent from the image processing unit 17a. Note that, in this example, an image conforming to the SVGA (Super Video Graphics Array) standard of 600 dots in the vertical direction and 800 dots in the horizontal direction is used.

As described above, the head mounted display using a toric lens according to the present invention has an analog toric lens that corrects the image displayed on the liquid crystal display panel and a toric mirror that reflects the image displayed on the liquid crystal display panel. A morphic optical system is formed. As a result, the length of the liquid crystal display panel in the front-rear direction can be shortened, and it can be restored by aspect conversion using a toric lens and a toric mirror. Thereby, the vertical dimension of the liquid crystal display panel can be reduced without changing the size of the image visually recognized by the user, and the thickness of the head mounted display device itself can be reduced.

[0024]

As described above, in the head-mounted display device of the present invention, the image on the image display section is radiated to the concave mirror by the toric lens and the toric half mirror, so that the image visually recognized by the user. The vertical dimension of the image display unit can be reduced without changing the size of the head-mounted display device, and the thickness of the head-mounted display device itself can be reduced. Further, according to the enlarged virtual image generation method of the present invention, the aspect ratio of the image is corrected by the toric lens, and an enlarged virtual image of the corrected image is generated. Even if it is an image, it is possible to generate an enlarged virtual image of the same size as before the reduction in thickness.

[Brief description of the drawings]

FIG. 1 is a principle diagram of the present invention.

FIG. 2 is a schematic sectional view of a head mounted display device of the present invention.

FIG. 3 is a diagram illustrating a shape of a toric lens.

FIG. 4 is a block diagram illustrating a circuit configuration of the head-mounted display device.

FIG. 5 is a diagram showing a schematic configuration of a conventional head-mounted display device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Image display part, 2 ... Toric lens, 3 ... Toric half mirror, 4 ... Concave mirror, 5 ... Image, 6 ... Enlarged virtual image

Claims (3)

[Claims] 1. A head-mounted display device used by being mounted on a head, comprising: an image display unit that displays an image; and an image display unit that is disposed in front of a surface of the image display unit that displays an image.
A toric lens for correcting the image size of the image display unit, a toric half mirror arranged to reflect the light transmitted through the toric lens, and the toric on the optical path of the light reflected by the toric half mirror. A concave mirror arranged to face the half mirror, and a head-mounted display device comprising: 2. The head-mounted display device according to claim 1, wherein the toric lens has an aspheric surface that enlarges an image displayed by the image display unit in a vertical direction. 3. An enlarged image generating method for generating an enlarged image to be displayed on a head-mounted display device used by being mounted on a head, wherein an aspect ratio of an image displayed by the image display unit is determined. Corrected by a toric lens, the corrected image corrected by the toric lens is reflected by a toric half mirror, and the corrected image reflected by the toric half mirror is reflected toward the half mirror unit by a concave mirror, An enlarged image generation method, characterized in that an enlarged virtual image of the corrected image is generated.