JP2013205602A - Three-dimensional image display method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a three-dimensional image display method that employs a transmission-type two-dimensional scan method, is not affected by aberration of a lens array, and eliminates the need of a flat display with high pixel density, with a simple light path.SOLUTION: A three-dimensional image display method includes the steps of: two-dimensionally arranging a plurality of basic units that two-dimensionally scan light beams emitted from a beam light source 9 and project the light beams in the air; and inputting a predetermined image signal 13 into the respective basic units to modulate brightness of the beam light source in accordance with the movement of the two-dimensional scan. The three-dimensional image display method employs transmission-type two-dimensional scan to simplify a configuration of an IV display device.

Description

  The present invention relates to a three-dimensional display device, and more particularly to a method for displaying a high-definition three-dimensional image with a simple configuration.

  FIG. 1 is a diagram showing a conventional IP display state.

  The size of the lenses of the micro convex lens two-dimensional array 1 and the distance between them are selected from about 0.1 mm to several tens of mm depending on the purpose.

  The flat display 2 is shown as a liquid crystal display in this figure, and is substantially in the focal plane of each lens of the micro-convex lens two-dimensional array 1, and displays a point image group G3 represented by 3a, 3b, 3c. doing.

  Light is transmitted only through the pixel portions of the point images 3a, 3b, 3c,... Displayed on the liquid crystal display 2 illuminated by the backlight 4, and the other portions block light from the backlight.

  Which pixels of the flat display 2 are to be transmitted and which pixels are to be shielded can be arbitrarily selected so that parallel light that passes through the flat display and exits through each lens of the micro-convex lens array 1 gathers at one point in space. Choose.

  Each point image (3a, 3b, 3c...) Is on the focal plane of each convex lens, and light emitted from each point image is emitted as substantially parallel light through each corresponding convex lens of the micro convex lens array 1. .

  A large number of parallel lights emitted from each convex lens are condensed at one point in the space to form an image, and diverge after being condensed.

  In this diverging cone of light, it appears as if there are nearly the same rays as when there is an actual image at the focal point.

  When an observer puts his eyes in this diverging light cone, the image is recognized at the focal point. If it is within the range, even if the observer moves his eyes or sees with both eyes, it always feels that the image is present at the original condensing point, and is displayed as a three-dimensional image 5. Will be.

  FIG. 2 is a diagram showing an example of the micro convex lens two-dimensional array 1.

  In conventional IP, a lens array is an indispensable element, but aberrations such as spherical aberration deteriorate the resolution of a three-dimensional image. In particular, if the viewing zone is to be expanded, a light beam that is inclined obliquely is handled, the aberration becomes very large, and the resolution of the three-dimensional image is greatly deteriorated.

  In addition, in order to obtain a high-resolution three-dimensional image, the flat display on the back side of the lens array needs to display a high-definition image in an area corresponding to each lens, and one minute image group that is a set thereof is displayed. In order to handle with a flat display, a flat display with super-multi-pixels and ultra-high pixel density is required. However, flat displays with super-multi-pixels and super-high pixel density are difficult in terms of current technology and are very expensive. There was a problem of becoming something.

  In order to solve the problem, the applicant stated in the previous patent application that “a plurality of basic units for two-dimensionally scanning a light beam and projecting it in the air are arranged two-dimensionally and a predetermined image is assigned to each basic unit. A “three-dimensional image display device” is proposed in which a signal is input and the beam light source is intensity-modulated in accordance with the movement of two-dimensional scanning.

  The proposal is a three-dimensional image display device in which the basic units shown in FIG. 3 are arranged in an array as shown in FIG. In FIG. 3, reference numeral 8 denotes a basic unit. The basic unit 8 includes a laser diode 9, a beam shaper 10, a fixed mirror 11, and a biaxial scanning mirror 12. A light beam emitted from the laser diode 9 is transmitted to the beam shaper 10. By passing the light, the light beam has a sharp tendency to spread in proportion to the distance, and is incident on the biaxial scanning mirror 12 via the fixed mirror 11. Reference numeral 3 'denotes an image signal input to the basic unit.

  The scanning of the biaxial scanning mirror 12 repeats the two-dimensional scanning at a speed of about 60 times or more per second, which is perceived as a continuous image without flickering by the afterimage of the human eye, for example, similar to a cathode ray tube television, Based on the image signal, the brightness of the laser diode is modulated in accordance with the movement of the biaxial scanning mirror 12 so that a predetermined grayscale image is projected into the air.

  This method makes it possible to eliminate lens aberrations that are unavoidable in integral photography using a conventional lens array.

  However, in the proposal of the application, since the two-dimensional scanning is performed by the movable mirror (the biaxial scanning mirror 12 in FIG. 3), the problem is that the optical path becomes complicated.

  In the present invention, there is provided a three-dimensional image display method using a transmissive light deflection method, which is not affected by the aberration of the lens array, and which eliminates the need for a flat display with a high pixel density, with a simple optical path.

  In order to solve the above problems, the present invention provides the following means.

  Two or more basic units that project the light beam emitted from the beam light source into the air by transmission two-dimensional scanning are arranged two-dimensionally, and a predetermined image signal is input to each basic unit to support the movement of the two-dimensional scanning Then, a three-dimensional image display method is provided, wherein the beam light source luminance modulation is performed.

  In the present invention, as is apparent from FIG. 5, the movable mirror, which has been considered indispensable in the past, can be eliminated, the optical path need not be folded back, and the configuration of the IV display can be simplified.

IP display principle explanatory diagram (in the case of one point light source image in the air) Micro convex lens two-dimensional array perspective view Example of conventional basic unit Perspective view of conventional example An embodiment of the present invention

  Hereinafter, embodiments of the present invention will be described in detail.

  As indicated by the white arrow from the left side of FIG. 5, the light beam from the laser diode 9 enters through the beam shaper 10 as a sharp light beam that tends to spread in proportion to the distance.

  The liquid crystal LQ whose refractive index changes with voltage is sealed in the gap between the two layers of the three fixed plate glasses G, and the interleaved transparent electrodes CT are arranged on the side of the plate glass G in contact with the liquid crystal, so that two orthogonal gradient electric fields ( When the horizontal scanning voltages Vh1, Vh2, Vh3 (.. vertical scanning voltages Vv1, Vv2, Vv3...) Are changed, the deflection angle of the light beam from the laser diode changes corresponding to the magnitude of the gradient electric field. Injected in the right direction of the figure.

  For example, as shown in FIG. 5, the two-axis scan is a scan similar to that of a cathode-ray tube television, and is performed at a speed of about 60 times or more per second, which can be felt as a continuous image without flickering in human eyes. Repeatingly, the luminance of the laser diode is modulated in accordance with the deflection of the transmission type biaxial deflecting unit shown in FIG. 5 based on the image signal 13 so that a predetermined grayscale image is projected in the air.

DESCRIPTION OF SYMBOLS 1 Micro convex-lens two-dimensional array 2 Planar display 3a, 3b, 3c Each point image 4 Backlight 5 Point light source image 6 Viewing area 8 Basic unit 9 Laser diode 10 Beam shaper 13 Image signal G Plate glass CT Transparent electrode LQ Refractive index with voltage Liquid crystal Vv1 in which V is changed One of the vertical scanning gradient voltages Vv2 The second vertical scanning gradient voltage Vv3 The third vertical scanning gradient voltage Vh1 One of the horizontal scanning gradient voltages Vh2 The second horizontal scanning gradient voltage Vh3 Third horizontal scan gradient voltage

Claims (1)

A plurality of basic units for two-dimensionally scanning a light beam emitted from a monochromatic or multi-color beam light source and projecting it in the air are arranged two-dimensionally,
In a three-dimensional image display device, wherein a predetermined image signal is input to each of the basic units, and the beam light source is intensity-modulated in response to a movement of two-dimensional scanning.
A substance whose refractive index changes with a voltage such as liquid crystal is sandwiched between two glass plates,
By changing the gradient of the electric field with the interdigital transparent electrode,
Two sets of one-dimensional scans of the light beam are orthogonally stacked,
A three-dimensional image display method characterized by performing two-dimensional scanning with a light beam.

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