JPS59174876A - Manufacture of hologram - Google Patents

Abstract

PURPOSE:To eliminate the restriction of the designing of the shape of a mask pattern by providing the mask pattern with a magnetic body, and applying magnetic force to the magnetic body to bring the mask pattern and a photosensitive base plate into tight contact with each other. CONSTITUTION:The mask pattern 9 is provided with the magnetic body at some part or made of the magnetic body, and a magnet 11, electromagnet, or magnetized material is placed on the reverse surface of the photosensitive base plate 10 to produce a magnetic field. Thus, the mask pattern is brought into close contact with the photosensitive base plate 10. The magnetic body uses magnetic metal such as Ni, Co, and Fe. The mask pattern 9, on the other hand, is formed by an optional method such as punching, etching and plating. Thus, the restriction of the designing of the shape of the mask pattern is eliminated. Further, deflection and oscillation are prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION When exposing a hologram image on a photosensitive substrate in a pattern, the present invention does not have any restrictions on the design of the shape of a mask pattern used to provide the pattern, and a normal exposure optical system can be used. The present invention relates to an improved hologram manufacturing method that is applicable and does not cause the problem of mask pattern distortion.

Holograms are effective as a means of recording and reproducing three-dimensional images, and this property can be used to create decorations, displays,
It is used as a mark to prevent counterfeiting.

By the way, in order to make holograms more complex and precise and to increase their value in the above-mentioned fields of application, when exposing a hologram to a photosensitive substrate, the exposed areas and unexposed areas of the hologram are patterned. A mask pattern is used for the purpose of forming a mask, and a mask pattern may be used only once, or twice or more. Using a transparent sheet-like substrate with a pattern as a mask pattern is not a good idea in terms of pattern formation because it causes scattering of light when it passes through the transparent sheet-like substrate. As the mask pattern, a punched sheet made by punching out a light-shielding sheet in a pattern is suitable. However, with a cutout sheet, it is easy to create a pattern such as a circular cutout, but when creating a ring-shaped pattern, the center part cannot be held on the sheet when the cutout is removed. Since such a pattern cannot be provided and the light-shielding portion must be continuous, there are restrictions on the design of the pattern shape. Although such a mask pattern may be placed horizontally on a horizontally placed photosensitive substrate, it is impossible to apply it to a vertically placed photosensitive substrate. In addition, the optical system becomes complicated when exposing a horizontally placed photosensitive substrate.Furthermore, when using a cutout sheet as a mask pattern, it is necessary to follow the design constraints of the loaf pattern shape as described above. However, if there are many comb-cut parts or if the light-shielding part is provided with a narrow pattern, the rigidity of the mask pattern itself will be reduced, causing it to bend or vibrate easily. Such defects occur even when the photosensitive substrate is placed horizontally, but are further exacerbated when the photosensitive substrate is placed vertically.

The present invention aims to solve the above-mentioned drawbacks of the conventional technology. In a hologram manufacturing method in which a photosensitive substrate is exposed to light and then developed, a mask pattern is used during exposure, the mask pattern has a magnetic material, and a magnetic field is applied to the magnetic material. The gist of the present invention is a method for manufacturing a hologram, which is characterized by bringing a striped pattern and a photosensitive substrate into close contact with each other.

In the present invention, holograms include Fresnel holograms,
It also includes holograms such as Fourier transform holograms and Fraunhofer holograms, image bolograms, rainbow holograms, holographic stereodulums, etc. that utilize these hologram formats, and general diffraction gratings. Further, the present invention can also be applied to the case where only a single beam of light is exposed.

FIG. 1 is a schematic diagram illustrating a process of exposing a white light reproduction type image hologram to a photosensitive substrate through a mask pattern.

In FIG. 1, the light emitted from a light source 1 is divided into three beams by a half mirror 2, one beam passes through a lens 3 and is irradiated onto an object 4 to be photographed, and the obtained object light is sent to an imaging lens 5.
As a result, the light beam forms an image on the photosensitive substrate and reaches the photosensitive substrate, and the other beam passes through the mirror 7 and lens 8 and reaches the photosensitive substrate as a reference beam. Both the object beam and the reference beam interfere to form interference fringes, and these interference fringes are exposed to the photosensitive layer 10b of the photosensitive substrate 10 through the opening of the mask pattern 9,
As a result, a latent hologram image is recorded, and then development is performed depending on the material of the photosensitive layer of the photosensitive substrate.
A hologram is formed.

The light used in the above is high coherence light,
Preferably Ar laser, He-Ne laser, He
- Laser light emitted from a laser light source such as a Cd laser is used.

In order to bring the above mask pattern into close contact with the photosensitive substrate, a magnetic material is provided in a part of the mask pattern, or the mask pattern itself is formed using a magnetic material.
A magnet, an electromagnet, or a magnetized substance may be placed on the back surface 1 of the photosensitive substrate to generate a magnetic field. As the magnetic material, it is preferable to use magnetic metals such as Ni, Co, and Fe.

FIG. 2 shows how the mask pattern 9 is placed on the back surface of the photosensitive substrate 10 with a magnet 11 and the two are brought into close contact by magnetic force.

In the above, the mask pattern can be formed by any method such as punching, etching, or plating.

According to the above-described method of the present invention, there are no restrictions on the design of the shape of the mask pattern, and mask patterns with minute shapes,
Even if there are multiple mask patterns, it can be easily fixed on a photosensitive substrate, and a complex and highly decorative hologram can be obtained.
In addition, multiple exposures in which the exposed area is changed each time is easy, and the mask pattern and the photosensitive substrate are brought into uniform and complete contact with each other by the magnetic field, and the mask pattern is opened due to the lifting of the mask pattern. Diffraction patterns may also occur at the edges of the holes.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an example of the exposure step of the method of the present invention,
FIG. 2 is a schematic diagram showing a method of bringing mask patterns into close contact. ■・・・・・・・・・・・・Light source 2 ・・・・・・・・・・・・8-7Era-3, 5, 8
...Lens 7...Mirror 9...Mask pattern 10...
・・・・・・・・・Photosensitive substrate XOa・・・・・・
...Substrate] Ob......Photosensitive layer 11...Grinding stone patent applicant Atsumi Konishi, patent attorney representing Dai Nippon Printing Co., Ltd.

Claims (1)

[Claims] In a hologram manufacturing method in which a photosensitive substrate is exposed to interference light obtained by irradiating light onto an object to be photographed and interference between object light and reference light, and then development is performed, a mask pattern is formed during exposure. 1. A method for producing a hologram, characterized in that the mask pattern has a magnetic material, and the mask pattern and the photosensitive substrate are brought into close contact by applying a magnetic field to exert a magnetic force on the magnetic material. .