JPH0955960A - Stereoscopic image pickup device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid overlapping of optical image by providing an optical barrier at a boundary between respective projecting lenses in the group of lenses. SOLUTION: A light-untransmitting barrier B is provided between respective projecting lenses. It is furthermore desired that the barrier B should not reflect light. The height (h) of the barrier B depends on the distance between the group of lenses and a subject/and it give with the minimum value (d) of this distance, the height (h) is obtained as the height (h) if the barrier from a main point = fd/(d-f). In the expression, (f) expresses the focal distance of a small lens and (d) expresses a minimum distance from the subvect to the group of the lenses. Light from object point 02 is cut off by the barrier B and does not form an image in the image forming area of the adjacent projecting lens. In this case, the optical barrier B may be the one formed by attaching metallic film, etc., to the side of each projecting lens by a technique such as spattering or the one provided with a metallic sleeve, etc., around it, and further may be the one installed in a groove provided at the boundary between the respective projecting lenses in the group of the lenses.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stereoscopic television, and more particularly to a stereoscopic television utilizing a lens group or a pinhole group, that is, a so-called integrated photography (IP) imaging device.

[0002]

2. Description of the Related Art As one of stereoscopic television systems which can be freely viewed from an arbitrary viewpoint, a so-called integral p using a group of convex lenses or a group of pinholes arranged in a plane.
Hotography (IP) is known. A case where this method is used with a lens group will be described below.

First, as shown in FIG. 5, a photographic film 3 is placed behind a lens group 2 composed of a plurality of convex lenses 2 ₁ , 2 ₂ , ..., 2 _n arranged on the same plane.
The subject 1 in front of is photographed. An image 3 of the subject 1 is formed on the photographic film 3 by the respective convex lenses 2 ₁ , 2 ₂ , ..., 2 _n.
1 , 3 ₂ , ..., 3 _n are imaged and photographed. Next, the photographed and developed photograph is arranged at the same position as the film when photographed on the lens group 2, and when the image on the photograph is viewed from the front of the lens group 2 in this state, a stereoscopically reproduced image can be seen.

However, with this method, it was difficult to take a moving image because the image was taken once on a film. To solve this problem, a method of directly imaging a lens group was invented by the present inventors and proposed in Japanese Patent Application No. 7-85437.
As a result, it becomes possible to capture a moving image by the IP method.

FIG. 6 shows an apparatus disclosed in Japanese Patent Application No. 7-85437, which includes a lens group 2 in which a plurality of convex lenses 2 ₁ , 2 ₂ , ..., 2 _n are arranged on one plane, a lens 8 and An image pickup device 9 is provided and a television camera 7 that takes an image of the entire lens group 2 is configured. The focal length f1 of each convex lens of the lens group 2 is a short focal length whose focus is immediately after the lens. When the subject 1 is placed at a distance sufficiently far from the focal length (the shortest distance is shown by d1 and the farthest distance is shown by d2 in the figure), the real images 11 ₁ , 11 of the subject are placed.
₂ , ..., 11 _n are produced by each lens in the vicinity of their focal point, ie in the vicinity of the focal plane 11 formed by the focal point of each lens. You can think of the real image as an object there, so if you take a picture of the entire lens group again with a television camera that is installed behind it, a film is installed at the position of the real image and the image is taken by each lens. In the same manner as described above, the individual real images formed by the lens group 2 are displayed on the image sensor 9.
By forming images 9 ₁ , 9 ₂ , ..., 9 _n , image signals (television signals) can be obtained. By displaying this television signal on a display device and seeing the display device through a lens group installed on the front surface of the display device,
The stereoscopic image is reproduced.

[0006]

However, the above-mentioned method of directly imaging the lens group also has a problem to be improved. FIG. 7 shows a state in which the vicinity of the lens group in this system is viewed from above or from the side. The image of the object point O1 is formed at the position P1 by the convex lens L _(n) of the lens group. In this case, in the image plane, the convex lens L _(n) of the lens group is within the diameter which is the imaging region. On the other hand, the image of the object point O2 is formed at the position of P2 by the same convex lens L _(n) . In this case, an image is formed within the diameter of the next convex lens L _{(n + 1)} . On the other hand, the object point O
3 is imaged at the position of P3 by the adjacent convex lens L _{(n + 1)} , and two optical images overlap and interfere with each other, causing a problem.

An object of the present invention is to provide a stereoscopic image pickup device capable of avoiding the overlapping of optical images.

[0008]

A stereoscopic image pickup apparatus according to the present invention includes a lens group composed of a plurality of convex lenses arranged on one plane, and a television camera for picking up an image of the entire lens group. In the device, an optical barrier is provided at a boundary between the convex lenses of the lens group.

Here, the optical barrier may be formed by depositing a metal film or the like on the side surface of each convex lens by a method such as sputtering, or by surrounding a metal sleeve or the like. It may be installed in a groove provided at the boundary between the convex lenses.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, an optical barrier is provided at a boundary between convex lenses of a lens group. FIG. 1 shows the operating principle of the present invention. FIG. 1 is a schematic cross-sectional view of a lens group, and a barrier B that does not transmit light is provided between each convex lens. It is further desirable that the barrier B does not reflect light.

The height of the barrier B depends on the distance between the lens group and the subject. If the minimum value of this distance is given, the height of the barrier from the principal point can be obtained as follows.

[0012]

## EQU1 ## h = fd / (df) f: focal length of small lens d: minimum distance to lens group of subject By doing so, the light at the object point O2 is blocked by the barrier, and the convex lens next to it No image is formed in the image forming area of.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 shows a plurality of circular convex lenses 2 ₁ , ..., 2
An example in which an optical barrier 13 is provided around each of _n is shown. The barrier 13 has the height h described above and is opaque so that light does not pass through and enter the adjacent convex lens. Further, it is desirable that the light be non-reflecting so that the light does not reflect and enter the lens surface. A preferred barrier material is a thin metal plate with a black coating on its surface or a black resin plate such as vinyl chloride. This is formed into a sleeve shape and is provided around the side surface of the convex lens.

FIG. 3 shows a rectangular convex lens 12 ₁ , ..., 1
An example using 2 _n is shown. The other configuration is the same as that of the example shown in FIG. 2 except for the shape of the convex lens.

FIG. 4 shows a partial schematic sectional view of still another embodiment of the present invention. On the television side of the lens group 2, a groove 14 is formed between the convex lenses 2 ₁ , ..., 2 _n forming the lens group, and an optical barrier 13 is provided in the groove 14. As the barrier 13, the metal plate or the resin plate described with reference to FIG. 2 may be inserted into the groove 14, or a light-impermeable and non-reflective resin liquid may be poured into the groove 14 to be solidified. .

[0017]

As described above, according to the present invention, I
In the method of directly capturing the P image, it is possible to avoid overlapping the optical images formed by the convex lenses of the lens group with each other and capture a good IP image.

In principle, a stereoscopic image reproduced from a signal picked up by this method can be freely viewed from an arbitrary viewpoint, which is useful as a stereoscopic television.

[Brief description of drawings]

FIG. 1 is a schematic view showing the principle of an optical barrier according to the present invention.

FIG. 2 is a schematic perspective view showing a lens group in an example of the present invention.

FIG. 3 is a schematic perspective view showing a lens group in an example of the present invention.

FIG. 4 is a schematic sectional view showing a lens group in an example of the present invention.

FIG. 5 is a diagram illustrating a conventional IP method.

FIG. 6 is a diagram illustrating an IP direct imaging method.

FIG. 7 is a diagram showing a state near a lens group in FIG.

[Explanation of symbols]

1 Object 2 Convex lens group 2 ₁ , 2 ₂ , ..., 2 _n Convex lens 3 Photographic film 3 ₁ , 3 ₂ , ..., 3 _n Image taken 7 Television camera 8 Lens 9 Image sensor 9 ₁ , 9 ₂ , ..., 9 _n Image taken 11 Focal plane 11 ₁ , 11 ₂ , ..., 11 _n Real image 12 Square convex lens 13 Optical barrier 14 Grooves L _(n) , L _{(n + 1)} convex lens B Optical barrier

Claims (1)

[Claims] 1. A stereoscopic image pickup device comprising a lens group composed of a plurality of convex lenses arranged on one plane, and a television camera for picking up an image of the entire lens group, wherein a boundary between the convex lenses of the lens group. A stereoscopic imaging device, wherein an optical barrier is provided on the.