JPS63306417A - Method for projecting stereoscopic image - Google Patents

Abstract

PURPOSE:To enable relative easy projection of large-sized stereoscopic videos by projecting a non-linearly polarizable light beam consisting of the video signal for one scanning line of the video for viewing with the left or the video for viewing with the right eye to the respective specular faces of a prescribed rotary polyhedral mirror. CONSTITUTION:Polarizing layers 11, 12 having the axes of polarization intersecting relatively orthogonally with the specular faces 5, 6 for reflecting the signals for the left eye and the right eye are mounted to the respective specular faces of the rotary polyhedral mirror 3 consisting of alternate repetitions of the same number of the specular face 5 for reflecting the video signal for viewing with the left eye and the specular faces 6 for reflecting the video signals for viewing with the right eye. The non-linearly polarizable light beam consisting of the video signal for one scanning line of the video for viewing with the left eye or the video for viewing with the right eye is projected to the respective corresponding specular faces. The reflected light thereof is projected to an image receiving body 7 having a polarization maintaining characteristic and the directions of the axes of polarization of the resulted video 8 for viewing with the left eye and the video 9 for viewing with the right eye are matched with the directions of the axes of polarization of polarizing spectacles 10 which are worn by an observer on both the right and left eyes and have the axes of polarization intersecting orthogonally with each other. The stereoscopically viewing videos of the large image plane size re thereby relatively easily projected.

Description

[Detailed description of the invention] Industrial applications The present invention relates to an image projection method.

Especially regarding the projection method of stereoscopic vision.

2. Description of the Related Art Many attempts have been made to project stereoscopic images onto a two-dimensional image receptor.

For example, the images seen by the left and right eyes are projected onto almost the same position on the same screen through red and blue optical filters, and the viewer wears red, seven and blue optical filter glasses on each eye. There is a way to appreciate it. Similarly,
A method of using polarizing filters having polarization axes orthogonal to each other in place of the red and back optical filters is also known.

Separately, each of the left-eye and right-eye visual images is projected alternately at high speed onto a surface receptor body, and the projected left-eye and right-eye visual images,
It is also known to watch through shutter glasses that open and close alternately on the left and right in synchronization with the Eirin.

The image receptor is divided into minute sections, each section is equipped with a polarizing layer with polarization axes orthogonal to each other, and one side of the stereoscopic image is displayed on each section coated with a polarization layer with polarization axes in the same direction. A method has also been proposed in which images are projected and viewed through polarized glasses having the same polarization axis as each image.

Separately, a method of forming a stereoscopic image using a hologram is also known.

However, these methods have drawbacks such as difficulty in forming large stereoscopic images, insufficient image sharpness, difficulty in forming color images, and the need for expensive shutter glasses. was there.

Problems to be Solved by the Invention There is a need for a method for projecting large stereoscopic images using a relatively simple method.

Means for Solving the Problems The present invention provides a rotating polygon mirror consisting of the same number of right-eye video signal reflecting mirror surfaces and right-eye video signal reflecting mirror surfaces that are alternately repeated. Polarizing layers having relatively orthogonal polarization axes are attached to the mirror surface for reflecting the signal and the mirror surface for reflecting the right-eye video signal, and one scanning line of the left-eye video or the right-eye video is attached to the corresponding mirror surface. An observer can determine the direction of the polarization axis of a left-eye image and a right-eye image obtained by irradiating a non-linearly polarized light beam consisting of an image signal and projecting the reflected light onto a polarization-maintaining image receptor. Provided is a stereoscopic image projection method characterized in that the direction of the polarization axis is aligned with the direction of the polarization axis of polarized glasses having mutually orthogonal polarization axes worn on the left and right eyes.

There is no known method of modulating a strong parallel beam of light, such as a laser beam, with a video signal, scanning it horizontally and vertically using a reflective angle-changing device such as a scanning mirror, and projecting the image onto a screen or other image receptor. ing.

In addition, when a rotating polygon mirror (polygon mirror) in which plane mirrors are arranged in the shape of a regular polygonal column is rotated around its rotation axis and a light beam modulated by a video signal is irradiated onto the mirror surface, the reflected light will produce one image per mirror surface. It is also known to provide a scanned image of signals on an image receptor. In this case, by changing the angle of incidence of the light beam incident on the single-rotation polygon mirror along the rotation axis of the polygon mirror, a two-dimensional image can be obtained on the image receptor.

The present invention was completed as a result of paying attention to these facts and researching methods for obtaining stereoscopic images. A specific example of the present invention will be described below with reference to the drawings.

In FIG. 1, 1 is a light source for projection. This light source may be of any type as long as it can generate a light beam that can ensure sufficient brightness on the image receptor. For example, a beam-type halogen lamp or xenon lamp such as a searchlight may be used, but a visible light laser is also a preferable light source. Examples of visible light lasers include helium-neon lasers, argon lasers, krypton lasers, helium cadmium lasers, steel vapor lasers, ruby lasers, dye lasers, and visible light semiconductor lasers. However, if the light source is a laser that generates a linearly polarized beam, insert a depolarizing element or a phase plate (especially a quarter-wave plate) in the optical path B1t or B2 between the light source 1 and the rotating polygon mirror 3. It is necessary to make the light beam incident on the rotating polygon mirror 3 non-linearly polarized. Such devices are well known in the art.

Modulation of the beam by a video signal can be performed by blinking or increasing or decreasing the light of the light source itself, but for example, devices normally used for this purpose, such as electro-optical modulators, ultrasonic light modulators, optical switches, and optical shutters, can be used in the optical path. You can also insert it inside.

Reference numeral 2 in FIG. 1 is a scanning mirror, which is a preferred device for providing a two-dimensional image to an image receptor by scanning a beam in a direction perpendicular to the scanning direction of the single-rotation polygon mirror 5. The scanning mirror 2 may be placed in front of or behind the one-rotation polygon mirror 3 in the beam optical path. Further, instead of the scanning mirror, an ordinary rotating polygon mirror may be used with the rotation axes of the rotating polygon mirror 3 orthogonal to each other.

The rotating polygon mirror 3 consists of a group of plane mirrors that rotate around a rotation axis 4 and are parallel to the rotation axis.

In FIG. 1, the mirror surface is shown to be composed of six mirror surfaces for illustrative purposes, but the invention is not limited to this.

The number is selected mainly depending on the scanning speed, the scanning width, the rotation speed of the rotating polygon mirror 3, the distance from the one-rotation polygon mirror to the image receptor, and the image density.

The rotating polygon mirror 3 has polarizing layers attached to all its mirror surfaces. However, the direction of the polarization axis of the polarizing layer.

The mirror surface for reflecting a right-eye visual video signal and the mirror surface for reflecting a right-eye visual video signal are mounted so as to be relatively perpendicular to each other.

In FIG. 1, for illustrative purposes, the mirror surface 5 for reflecting a left-eye video signal and the mirror surface 6 for reflecting a right-eye video signal are alternately repeated one by one. It may consist of alternating repetitions of mirror groups for reflecting video signals and the same number of mirror surfaces for reflecting right-eye viewing video signals. It has been found that when a specular upper pressure polarizing layer is attached in this manner, an incident non-linearly polarized light beam is reflected as a linearly polarized beam along the polarization axis of the polarizing layer.

The polarizing layer may be an iodine-side polarizing film, an organic dye-based polarizing film, or an inorganic birefringent polarizing plate.

These polarizing layers may be attached to each mirror surface of the rotating polygon mirror using an adhesive, screws, or the like.

The rotating polygon mirror 3 is irradiated with a non-linearly polarized light beam B2 modulated by a video signal from a light source. In this case, the video signal beam irradiated onto one mirror surface of the one-rotation polygon mirror S corresponds to one scanning line of the image projected on the receiver. Then, a video signal beam of the left eye image is irradiated on the mirror surface for reflecting the left eye image signal.
The same applies to right-eye images. In the example shown in FIG. 1, after a light beam for one scanning line of the left-eye visual video signal is irradiated onto the mirror surface 5 for reflecting the left-eye visual video signal, the next mirror surface 6 for reflecting the right-eye visual video signal is irradiated.
When the video signal beam is sequentially irradiated at the irradiation angle adjusted by the scanning mirror 2 so as to irradiate one scanning line of the right eye image signal, the reflected beam from the one-rotation polygon mirror 5 is reflected from the left eye image signal. The image signal beam of the image and the image signal beam of the right-eye image are projected onto the image receptor 7 as linearly polarized beams having polarization axes orthogonal to each other. The scanning line image 8 of the left-eye image projected onto the image receptor 7 and the scanning line image 9 of the right-eye image projected onto the image receptor 7 are shown in two stages in FIG. The scanning line image 8 of the visual image and the scanning line image 9 of the right visual image may overlap on the image receptor.

In the optical path from the light source 1 to the image receptor 7, an optical system such as a lens, a prism, etc., for converging, diffusing, correcting distortion, or refracting the light beam may be inserted as necessary.

It is necessary that the image receptor 7 has a polarization-maintaining surface so that the reflected light (or transmitted light) of the projected image remains in the straight direction.

Such image receptors are, for example, glass bead coated screens, metal foil coated surfaces or microprism plates.

When viewed with the naked eye, the image obtained by the stereoscopic image projection method of the present invention is observed as an overlapping image of a left-eye image and a right-eye image. In order to view oneself stereoscopically, an observer wears polarized glasses 10 on the left and right eyes, each having polarizing layers 11 and 12 having polarization axes orthogonal to each other. The direction of each polarization axis is within the reflected (transmitted) image from the image receptor 7.

It must match those of the left eye image and right eye image, respectively. This is determined by which of the polarizing mirror surfaces 5 and 6, which have polarization axes orthogonal to each other, is to be irradiated with the left (right) visual image signal that is irradiated onto the rotating polygon mirror 3 prior to projection. In fact, if the stereo image cannot be viewed normally when viewed with polarized glasses, it can be easily corrected by shifting the phase of the left and right electric signals.

To project a color image, the red, green, and front light beams are simultaneously irradiated onto the same polarizing mirror surface of the rotating polygon mirror 3, and the optical paths are adjusted so that they are projected onto substantially the same point on the image receptor 7. It is possible.

Effects of the Invention According to the present invention, a large-screen stereoscopic image can be projected relatively easily.

[Brief explanation of drawings]

FIG. 1 shows one embodiment for explaining the projection method of the present invention. In FIG. 1, 1 is a light source, 2 is a scanning mirror, and 3 is a rotating polygon mirror. 4 is its rotation axis, 5 is a mirror surface for reflecting left-eye visual video signals, 6 is a mirror surface for reflecting right-eye visual video signals, 7 is an image receptor, 8 is a left-eye visual video signal image for one scanning line, and 9 is 1 A right-eye visual signal image of a scanning line segment, 10 denotes polarized glasses for an observer. 11 is a polarizing layer for viewing with the left eye, 12 is a polarizing layer for viewing with the right eye, and B1. B2 and B3 are shown as optical paths of the light beams. Patent applicant Nippon Kayaku Co., Ltd. Figure 1

Claims (1)

[Claims] 1. Each mirror surface of a rotating polygon mirror is made up of alternating repetitions of the same number of mirror surfaces for reflecting left-eye visual video signals and mirror surfaces for reflecting right-eye visual video signals. A polarizing layer having a polarization axis relatively orthogonal to the reflecting mirror surface is attached, and non-linearly polarized light consisting of a video signal for one scanning line of a left-eye image or a right-eye image is applied to each corresponding mirror surface. The directions of the polarization axes of the left-eye image and the right-eye image obtained by irradiating a beam and projecting the reflected light onto a polarization-maintaining image receptor are set perpendicular to each other by an observer wearing the left and right images. A stereoscopic image projection method characterized by aligning the direction of a polarization axis of polarized glasses having a polarization axis.