JPH06175569A - Manufacture of holographic optical element and holographic stereogram using the same - Google Patents

Abstract

PURPOSE:To improve the utilization efficiency of light and to shorten the whole synthesis time. CONSTITUTION:An original image can be reproduced by irradiating original image film 1 with a coherent light, for example, a laser beam 2. Incident light from the original image film 1 is focused on a holographic optical element 4 via a projection lens 3. Furthermore, a hologram film 5 is irradiated with the light from the holographic optical element 4. Also, the hologram film 5 is irradiated with a reference light 6. In such a case, the holographic optical element 4 has, for example, diffusivity, how-ever, it has property not being diffused on a part other than an element hologram desired to expose, and it is generated by photographing the light from a diffusion screen and a slit holographically.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a holographic stereogram produced by sequentially exposing an original image sequence on element holograms.

[0002]

2. Description of the Related Art A conventional holographic stereogram is created, for example, as shown in FIG. That is, in the figure, reference numeral 41 is an original image film, and the original image is reproduced by irradiating the original image film 41 with coherent light, for example, a laser beam 42. Reproduced light from the original image film 41 is applied to the field lens 44 and the diffusion screen 45 via the projection lens 43 so as to be focused.

Further, the light from the diffusing screen 45 is applied to the hologram film 47 through the slit 46. In addition, the slit 46 and the hologram film 4
The reference light 48 is applied to the beam 7. As a result, the light from the diffusing screen 45 is holographically imaged on a part of the hologram film 47 limited by the slit 46 (referred to as an element hologram).

Then, the holographic stereo image is formed on the hologram film 47 by sequentially exchanging the original image sequence of the original image film 41 and moving the slits 46 in the vertical direction (vertical direction in the drawing) to perform exposure. Grams are created. That is, as the original image film 41, one which can obtain a correct parallax is used, and the original image sequence of this original image film 41 is processed by the hologram film 4 by the above-described procedure.
7 is exposed.

As a result, the holographic stereogram, which is recognized as a solid when the whole is reproduced,
It is created on the hologram film 47.

However, in the method for producing such a holographic stereogram, when the diffusing screen 45 is used, light is diffused other than the element hologram to be exposed, and the light is wasted. For this reason, there is a problem that the time required for exposure increases by the amount of this wasted.

In the above manufacturing method, the field lens 44
Are provided in the vicinity of the slit 46 to efficiently collect light. However, even if such a measure is added, the light is diffused to other than the opening portion of the slit 46, and it becomes useless light.

If the number of element holograms is made small to increase the image quality of the holographic stereogram and the number thereof is increased, the amount of wasted light is further increased, and the total synthesis time of the holographic stereogram is significantly increased. I will end up. This application is made in view of such a point.

[0009]

The problem to be solved is that in the conventional manufacturing method, light is diffused in addition to the element hologram to be exposed, and the light is wasted, so that the time required for the exposure is increased. It will increase. Therefore, if the element holograms are made small to improve the image quality of the holographic stereogram, the total synthesis time will be significantly increased.

[0010]

A first feature of the present invention is that a holographic stereogram used for producing a holographic stereogram by sequentially exposing an original image sequence (original film 1) on element holograms (holographic film 5). A holographic optical element, which is a graphic optical element and is composed of a hologram film 4 having a property of diffusing the light from the original image sequence but not diffusing into other than the element hologram to be exposed. .

A second feature of the present invention is that the hologram film 4 is constructed by hologram-photographing light through the diffusing screen 21 and the slit 22 formed in a line. It is a holographic optical element as described in the first feature.

A third feature of the present invention is that the hologram film 4 is a hologram image of light that has passed through a diffusion screen and a mask having a predetermined dot shape. It is a holographic optical element.

A fourth feature of the present invention is a method for producing a holographic stereogram produced by sequentially exposing an original image sequence (original image film 1) on element holograms (hologram film 5). This is a method for producing a holographic stereogram in which the exposure is performed using a holographic optical element 4 which has a property of diffusing light but not diffusing other than the element hologram to be exposed.

A fifth feature of the present invention is that the holographic optical element 4 comprises a diffusing screen 2.
The method for producing a holographic stereogram according to the above fourth characteristic is characterized in that the light passing through 1 and the slit 22 is a hologram image.

A sixth feature of the present invention is the fourth feature characterized in that the holographic optical element is a hologram image of light passing through a diffusion screen and a mask having a predetermined dot shape. It is a method of producing a holographic stereogram.

[0016]

According to this, the field lens 44, the diffusing screen 45, and the slit 46 described above are unnecessary, so that the utilization efficiency of light is improved and the total synthesis time can be shortened. Further, even if the element hologram is made small, its spectrum is concentrated and the exposure time of one element hologram is shortened. Therefore, even when a high quality holographic stereogram is created, the increase in the composition time can be suppressed to a small extent. it can.

[0017]

EXAMPLES In FIG. 1, reference numeral 1 is an original film,
The original image film 1 is irradiated with coherent light, for example, laser light 2 to reproduce the original image. The reproduction light from the original image film 1 is emitted via a projection lens 3 so as to focus on a holographic optical element 4 described later. Further, the light from the holographic optical element 4 is reflected by the hologram film 5
Is irradiated. Further, the hologram film 5 is irradiated with the reference light 6.

As a result, the hologram film 5 restricted by the holographic optical element 4 is formed.
The light from the holographic optical element 4 is holographically captured on a part (element hologram) of the. In addition, holographic optical element 4
The incident angle and the like of the reference light 6 are determined so that the 0th-order light 7 from is not applied to the hologram film 5.

Here, the holographic optical element 4 has, for example, a diffusive property, but has a property of not diffusing other than the element hologram to be exposed. That is, such a holographic optical element 4 is produced, for example, as shown in FIG.

In FIG. 2A, the diffusion screen 21
The incident light 23 is applied to the hologram film 24 through the slit 22 and the reference light 25 is applied to the hologram film 24. This allows the diffusion screen 2
The light from 1 and the slit 22 is holographically captured.

As shown in FIG. 2 (b), the slit 22 is a line-shaped slit formed by attaching a metal film of chromium or the like to a base made of glass by vapor deposition or coating to form an opaque film. It is configured such that the metal film is not adhered only to the gap portion. The slit has a length and a width corresponding to one line in the vertical direction of the image to be recorded. The width of one line is, for example, about 0.1 to 2.0 mm, but theoretically it is desirable that the width is about 0.3 mm or less.

When the holographic optical element 24 as described above is illuminated with the light conjugate with the reference light, the slits 22 photographed as shown in FIGS.
The light is diffused in the range of, and is not diffused in other areas. In addition, A is a view seen from the lateral direction of the photographed slit 22, and B is a view seen from the vertical direction.

Therefore, when the object light from the original image film 1 is incident on the holographic optical element 4 as shown in FIG. Are diffused in the area of the slit 22 that has been photographed. As a result, the same effect as that of the light from the diffusing screen 45 of FIG. 4 irradiating the hologram film 47 through the slit 46, and the diffused object light is holographically displayed on a portion (element hologram) of the hologram film 5. To be taken.

In this case, the light is not diffused except the element hologram to be exposed, so that the light is effectively used and the time required for the exposure is shortened. Also, if the element holograms are made smaller to improve the image quality of the holographic stereogram, the concentration of light will increase accordingly, and the exposure time per element hologram will be shortened. There is no increase in the synthesis time as in the past.

Further, since the conventional slit 46 is unnecessary, the mechanism around the hologram film 5 can be simplified. Further, the viewing angle of the holographic stereogram is determined by the viewing angle from the element hologram of the diffusing screen and the viewing lens, which is advantageous for widening the viewing angle according to the above-mentioned manufacturing method.

As described above, according to the above-mentioned manufacturing method, the light utilization efficiency is improved and the total synthesis time can be shortened. Further, even if the element hologram is made small, its spectrum is concentrated and the exposure time of one element hologram is shortened. Therefore, even when a high quality holographic stereogram is created, the increase in the composition time can be suppressed to a small extent. It is possible.

In the above embodiment, the Fresnel hologram type holographic stereogram having only the lateral parallax is explained, but the manufacturing method of the present application can be applied to various other types of holographic stereograms. That is, for example, in order to add a parallax in the vertical direction, a rectangular mask as shown in FIG. 2C is used instead of the slit 22 when the holographic optical element 4 is created.

By this, the object light can be diffused in the rectangular range, and a holographic stereogram having parallax in the vertical and horizontal directions can be created by using this holographic optical element 4. It should be noted that this mask may have a size corresponding to one pixel of the video signal or a size corresponding to a plurality of pixels as long as it has a predetermined dot shape. Further, it may be configured in a shape other than a rectangle, such as a circle or a triangle.

Further, the manufacturing method of the present application is also effective for a Lippmann holographic stereogram. The present invention can also be applied to an alcove type, a cylindrical type, and a disc type holographic stereogram by arbitrarily determining the shape of the slit when the holographic optical element 4 is produced.

[0030]

According to the present invention, the utilization efficiency of light is improved and the total synthesis time can be shortened. In addition, even if the element hologram is made smaller, its spectrum is concentrated and the exposure time for one element hologram is shortened.
Even when a high quality holographic stereogram is created, the increase in composition time can be suppressed to a small level.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an example of a method for producing a holographic stereogram according to the present invention.

FIG. 2 is a diagram for explaining a holographic optical element.

FIG. 3 is a diagram for explaining the explanation.

FIG. 4 is an explanatory diagram of a conventional manufacturing method.

[Explanation of symbols]

 1 original image film 2 coherent light, for example laser light 3 projection lens 4 holographic optical element 5 hologram film 6 reference light 7 0th order light

Claims (6)

[Claims] 1. A holographic optical element for use in producing a holographic stereogram by sequentially exposing an original image sequence onto element holograms, wherein the light from the original image sequence has a diffusive property and is exposed. A holographic optical element comprising a hologram film having a property of not diffusing other than the element hologram. 2. The holographic optical element according to claim 1, wherein the hologram film is formed by taking a hologram of light that has passed through a slit formed in a line shape with a diffusion screen. 3. The holographic optical element according to claim 1, wherein the hologram film is a hologram image of light that has passed through a diffusion screen and a mask having a predetermined dot shape. 4. A method for producing a holographic stereogram, which is produced by sequentially exposing an original image sequence onto element holograms, wherein the light from the original image sequence has a diffusive property, except for the element holograms to be exposed. A method for producing a holographic stereogram in which the above exposure is performed using a holographic optical element having a non-diffusing property. 5. The method for producing a holographic stereogram according to claim 4, wherein the holographic optical element is a hologram image of light passing through a diffusion screen and a slit. 6. The method for producing a holographic stereogram according to claim 4, wherein the holographic optical element is a hologram image of light that has passed through a diffusion screen and a mask having a predetermined dot shape.