JPH0121489B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a stereoscopic camera with a lenticular screen.

This type of stereoscopic camera has a lenticular screen consisting of a number of semi-cylindrical lens elements arranged adjacent to each other in front of the photosensitive material, and the action of this screen allows the same subject to be viewed from different angles. The images are formed in alternating striped images. This image is viewed stereoscopically by placing a lenticular screen having the same optical configuration as the lenticular screen above and viewing the image through the lenticular screen. This type of stereoscopic photography is called a direct-view stereoscopic photography because it does not require a special viewing device (viewer).

However, in this direct-view type stereoscopic photography, photography is performed using a single photographing lens system, so the image of the subject is projected onto the photosensitive material upside down and horizontally, as in the case of normal photography. Ru. Therefore, the left and right sides of the image are also reversed within the photosensitive surface divided into individual lens elements of the lenticular screen. In the image obtained in this manner, the image corresponding to the left side of the subject faces the observer's right eye through the lenticular screen, and the image corresponding to the left side of the subject faces the observer's right eye through the lenticular screen. Since the image corresponding to the right side faces the left eye through the lenticular screen, stereoscopic viewing is not possible in this state. Such an image is usually called an inverted stereoscopic image.

As a method to solve the above-mentioned problems in direct-view stereoscopic photography,
The one described in Publication No. 82333 is known.

The stereophotographic production method described in JP-A-53-82333 involves supporting a photosensitive material closely behind the flat side of a fixed lenticular screen, and supporting the photosensitive material closely behind the flat side of the lenticular screen. An image consisting of an inverted 3D image is once formed on a photosensitive material using a stereophotographic camera having a photographing lens with an effective aperture extending in the parallel direction of the lens elements, and then an image consisting of an inverted 3D image previously prepared in this way is A photosensitive material (original plate) having an image array consisting of a three-dimensional image is placed in the projection light path of an enlarger, and a set of two lenticular screens, which are placed in close contact with each other in opposite directions, is placed in close contact with this original plate and placed on photographic paper. A normal 3D image is obtained by projecting an image consisting of a 3D image obtained by converting the image arrangement.

According to the 3D photograph production method described in JP-A-53-82333, it is possible to obtain a 3D image without the need to photograph the same subject multiple times. Its use makes it possible to photograph moving objects, and it also has the advantage that it can be photographed simply with a camera equipped with a lenticular screen in front of the photosensitive material. However, when the subject distance changes, the photographing lens is moved for focusing and the distance between the photographing lens and the lenticular lens changes, so the exit angle of light from the photographing lens changes and the lenticular lens changes. This method has the disadvantage that the object image cannot be accurately formed on the photosensitive material due to the refractive effect of the curved surface of the lens element of the color screen. In other words, it has the disadvantage that only objects at a substantially constant distance can be photographed well. Therefore, in order to always obtain a good image even when the subject distance changes using the method of JP-A-53-82333, several lenticular screens with different radii of curvature of the curved surface of the lens element are prepared. The lenticular screen must be replaced every time the subject distance changes. This has the drawback of being troublesome to handle and requiring a large number of different lenticular screens to be prepared, resulting in high costs.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a stereoscopic camera that eliminates the drawbacks of the conventional stereoscopic camera and eliminates the need to replace the lenticular screen even when the subject distance changes. It is.

In order to achieve this objective, in the present invention,
With the rear part of the photographic lens fixed, the distance between the rear part of the photographic lens system and the lenticular screen is constant regardless of the subject distance, that is, the exit angle of light from this rear part is constant, and the distance between the photographic lens system and the photosensitive material is kept constant. The object image is always formed on the photosensitive material even when a lenticular screen is interposed between the two.

That is, the stereoscopic camera according to the present invention consists of a large number of semi-cylindrical lens elements arranged adjacent to each other, a fixed lenticular screen with one side having a flat surface and the other side having an uneven curved surface, and this lenticular screen. a supporting means for closely supporting a photosensitive material on the back of the flat side of the lenticular screen; a photographing lens system having an effective opening extending in the parallel direction of the lens elements at the front of the curved side of the lenticular screen; and the photographing lens. A stereoscopic photographic camera having an exposure shutter provided in an optical path of the system so as to be movable in and out, and for forming an image consisting of an inverted stereoscopic image on the photosensitive material by the photographing lens system, the photographing lens The system uses a front lens extension system consisting of a front element that can be moved back and forth and a fixed rear element, and the distance of the lens system can be adjusted by moving only the front element, regardless of the distance of the subject. The feature is that the distance between the rear part of the system and the lenticular screen is always constant.

Hereinafter, preferred embodiments of the stereoscopic camera according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a diagram schematically showing an optical system used in the stereoscopic photographic camera of the present invention. This optical system includes a fixed lenticular screen 1 consisting of a large number of semi-cylindrical lens elements arranged adjacently in parallel, and an effective opening located in front of the curved surface of the lenticular screen and extending in the parallel direction of the lens elements. The camera is comprised of a photographic lens system 2, and an exposure shutter 3, which is provided in and out of the optical path of the photographic lens system. The lenticular screen 1 may have a normal configuration,
That is, a large number of identical elongated semi-cylindrical lens elements each having a width of approximately 0.5 to 5 mm are arranged adjacently in parallel. The front curved surface of each lens element of this lenticular screen has the same radius of curvature such that the light from the taking lens system is focused at the position of the rear plane of this lenticular screen. The radius is selected. The lenses constituting the photographic lens system 2 are either ordinary circular lenses or are formed by cutting two planes that are parallel to the optical axis of the lens, equidistant from this principal axis, and parallel to each other. It could be a lens. When using the latter as the photographic lens system, the photographic lens system is arranged with the longitudinal direction of the lens oriented across the lens elements of the lenticular screen, that is, in the parallel direction of the lens elements. In the embodiment shown in the figure, the shutter 3 is placed behind the photographic lens system, but if it can be inserted into and taken out from the optical path of the photographic lens system, it may be placed in front of the photographic lens system. Of course it's good too. Further, it is desirable that the shutter 3 is a shutter that, when opened, forms a slit extending in the parallel direction of the lens elements of the lenticular screen.

The back of the lenticular screen 1 is provided with supporting means, such as a film holding frame and a pressure plate (not shown), for supporting the photosensitive material 4 in close contact with the rear plane of the lenticular screen 1. It is being

Since the optical system used in the stereoscopic camera has a configuration almost as described above, the light 5 from the subject passes through the photographic lens system 2 and reaches the lenticular screen 1 when the shutter 3 is opened. Furthermore, it passes through this and converges on the surface of the photosensitive material 4. That is, the image of the subject is accurately formed on the photosensitive material 4.

In the stereoscopic photographic camera of the present invention, the photographing lens system is of a front lens extension type consisting of a front lens 6 that is movable back and forth and a fixed rear portion 7. This front ball feeding method is also called the front ball rotating method, and the usual method is to move only the front ball forward and backward using a screw. This front lens feeding lens is
When adjusting the focus, only the front lens 6 is moved and the rear lens 7 is fixed, so the distance from the rear lens 7 to the lenticular screen 1 is always constant regardless of the subject distance (first and second lenses). (See Figure 2). That is, when the subject is at infinity, the front lens 6 is located relatively close to the rear part 7, as shown in FIG. The ball 6 is paid out in a direction away from the rear part 7. In any case,
The photographic lens 2 of the front lens extension type is characterized in that the rear part 7 is fixed, so the distance between the rear part 7 and the lenticular screen 1 is constant, and the exit angle of light from the rear part 7 is always constant. constant. For this reason, no matter how the subject distance changes,
The light from the subject that has passed through the photographic lens system 2 always enters the lenticular screen 1 under constant conditions, so that it can always be imaged at the same position using the same lenticular screen. .

Therefore, in the stereoscopic photographic camera of the present invention, which has a configuration in which a front lens extension type photographic lens system is incorporated into a conventional stereoscopic photographic camera equipped with a lenticular screen, the lenticular screen can be replaced ( That is, there is no need to replace the front surface of the lens element with a lenticular screen having a different radius of curvature, and thus the camera only needs to have one lenticular screen. For the same reason, there is no need to provide a removable lenticular screen, and it can be fixed at the same position, which simplifies the structure of the camera itself. Furthermore, since photography can be performed simply by adjusting the distance, stereoscopic photographs can be taken with the same easy operations as with a normal camera.

Since the image taken by the stereoscopic camera of the present invention is an inverted 3D image, the inverted 3D image can be inverted and made into an upright 3D image using the method described in Japanese Patent Application Laid-Open No. 53-82333. use.

[Brief explanation of drawings]

FIG. 1 is a schematic plan view showing the optical system used in the stereoscopic camera according to the present invention in the arrangement when the subject is at an infinite distance, and FIG. , is a schematic plan view showing the arrangement when the subject is at a finitely distant position. 1... Lenticular screen, 2... Photographic lens system, 3... Shutter, 4... Photosensitive material,
5...Light from the subject, 6...Front lens, 7...Rear.

Claims (1)

[Claims] 1. A fixed lenticular screen consisting of a large number of semi-cylindrical lens elements arranged adjacent to each other, supporting means for supporting a photosensitive material in close contact with the back of the lenticular screen on the flat side;
A photographic lens system is provided in front of the curved surface of the lenticular screen and has an effective opening extending in the parallel direction of the lens elements, and an exposure shutter is provided in the optical path of the photographic lens system so as to be able to move in and out. and a stereoscopic photographic camera for forming an image consisting of an inverted stereoscopic image on the photosensitive material by the photographing lens system, wherein the photographing lens system is composed of a front lens that is movable back and forth and a fixed rear part. The front element is moved forward, and the distance between the lens system is adjusted by moving only the front element, so that the distance between the rear of the lens system and the lenticular screen is always constant regardless of the distance of the subject. A three-dimensional photographic camera characterized by: