JP3224587B2 - Hologram recording method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hologram recording method for recording a Lippmann hologram with good stability.

[0002]

2. Description of the Related Art A conventional Lippmann hologram recording method will be described with reference to FIGS. FIG. 5 shows an ordinary method of recording a Lippmann hologram. After a coherent light 21 is split into two by a half mirror 22, the split light flux is passed through mirrors 23 and 24 and lenses 25 and 26, respectively, to the opposite side of the recording material 20. This is a method of recording by irradiating from the side and causing interference in the recording material.

FIG. 6 shows that a light beam from a light source is irradiated on a recording material 20 through a lens 31, and a transmitted light of the light beam from the recording material is reflected on a reflection surface 30 and then irradiated on the recording material again, so that the incident light and It is recorded with interference.

[0004]

In the method shown in FIG.
Since the light beam is divided into two and then irradiated onto the recording material, the optical path length to the recording material is long, and there are many reflective surfaces.
There has been a problem that the optical components are easily affected by disturbances such as vibration, convection of air, deformation of optical components due to temperature change, and wavelength variation of the light source. The method shown in FIG. 6 is excellent in stability because the optical path length is short, the number of reflecting surfaces is small, and the recording material and the reflecting surface can be fixed relatively. To select a variety of shapes, it is necessary to polish a curved surface with a complicated shape. Especially, the incidence and diffracted light of the hologram often have an angle with respect to the normal of the hologram, so it is necessary to form it in an off-axis shape. is there. This is technically difficult, and has the problem of cost and production time, and this difficulty increases especially as the size of the hologram increases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a hologram recording method capable of obtaining a desired divergence distance, having good recording stability, and reducing the size of the apparatus. The purpose is to:

[0006]

FIG. 1 is a diagram showing a basic configuration of the present invention. In the figure, 1 is a recording material, 2 and 3 are reflection surfaces, 4 is a lens, and A and B are light beams. In the recording of the Lippmann hologram according to the present invention, a light beam to the same light source is applied to the recording material 1 via the lens 4 and the light beam transmitted through the recording material 1 is reflected on, for example, the reflection surfaces 2 and 3.
And then re-enter the recording material to cause interference to form and record interference fringes. Since the transmitted light is reflected via the reflecting surfaces 2 and 3, the optical path can be lengthened,
The same operational effects as those obtained by using light from a divergent light source that is virtually distant can be obtained. As shown in FIG. 2, if a fixing member 11 on which the recording material 10 is placed and a reflecting member 12 having a surface for reflecting the light transmitted through the recording material are integrally formed to form a prismatic shape, the fixing member can be fixed. Since the member and the reflecting member are integrated, it is possible to perform stable recording that is strong against vibration and the like. In this case, the fixing member 11, the reflecting member 1
If the transparent liquid is put in the frame formed by the fixing member 11, reflection on the back surface of the fixing member 11 can be prevented. In FIG. 1 and FIG. 2, the reflecting surface is two surfaces, but the present invention is not limited to this. The reflecting surface may have three or more planes, and the reflecting surface has at least one surface.
First, if the surface is a quadratic surface, reflected light from various wavefronts can be obtained.

[0007]

According to the present invention, in a method of recording interference fringes by irradiating a recording material with light beams from opposite directions, a light beam from a light source is applied to the recording material and at least two light beams transmitted from the recording material are transmitted. By injecting the recording material again after passing through the reflection surface, the divergence distance of the incident light beam from the back surface side is lengthened, and at least one of the reflection surfaces is made flat, so that the recording apparatus can be formed at low cost. And the size of the device can be reduced. Further, the member for fixing the recording material and the member for reflecting the transmitted light are integrally formed, so that the stability against vibration and the like can be improved, and stable recording can be performed.

[0008]

FIG. 3 and FIG. 4 show an embodiment of the present invention. In this embodiment, the optical system shown in FIG. 2 is used. The distance of the divergence point 13 of the incident light beam from the center of the recording material is 30 cm, the incident angle is 60 °, and the divergence point of the reflected light beam is the center of the recording material. At a distance of 64 cm, an incident angle of 30 °,
Agfa-Gevaert 8E75H as recording material
D, and a Kr laser wavelength of 647 n as the light source 13.
m, the exposure amount is 30 mJ / cm ² , and the developer is CWC
2. PBQ2 was used as the bleaching agent. In the optical system of this embodiment, as shown in FIG. 4, the light source 13 is placed at a distance of 30 cm from the divergence point, and the light source 14 is placed at a position 64 cm away from the divergence point on the opposite side. This is equivalent to 30 °.

When a Lippmann hologram was recorded using such an optical system, a hologram having specifications could be produced with good stability.

[0010]

As described above, according to the present invention, by integrating components, it is possible to perform stable recording that is strong against vibrations and the like. In general, a transparent plate is generally used for the recording material fixing surface. In this method, so-called back surface reflection occurs at the interface between the back surface of the transparent plate and air, but as in the present invention, a transparent plate is used. By using a simple prism, reflection on the back surface can be eliminated. Further, in the combination of only plane surfaces, only divergent light and divergent light, or convergent light and convergent light can be interfered.
Since it can be a next curved surface or the like, it is possible to arbitrarily convert the positive and negative and absolute values of the curvature of the wavefront. Further, by adjusting the width of the light beam, the ratio of the irradiation energy per unit area of the two light beams to the recording material, R / O, is ideally set to 1.
It is also possible to approach zero.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a recording method of the present invention.

FIG. 2 is a diagram illustrating a hologram recording method of the present invention in which a fixing member and a reflecting member are mechanically fixed.

FIG. 3 is a diagram illustrating an embodiment of the present invention.

FIG. 4 is a diagram illustrating an embodiment of the present invention.

FIG. 5 is a diagram showing a conventional Lippman hologram recording method.

FIG. 6 is a view showing a conventional Lippmann hologram recording method.

[Explanation of symbols]

1, 10: recording material, 2, 3: reflection surface, 4: lens, 1
1 ... fixed member, 12 ... reflective member.

Claims (7)

(57) [Claims] In a Lippman hologram recording method for recording interference fringes by irradiating light onto a recording material from directions opposite to each other, a light beam from a light source is irradiated on the recording material, and the light beam is emitted from the recording material. At least 2 transmitted light
A hologram recording method , comprising: irradiating the recording material again after being reflected by two reflection surfaces, causing the light to interfere with the light beam, and recording the interference fringes . 2. The recording method according to claim 1, further comprising a fixing member for fixing the recording material, wherein the fixing member and the reflecting member having at least two reflecting surfaces are mechanically connected. A method for recording a hologram that is a feature. 3. The hologram recording method according to claim 2, wherein the fixing member and the reflecting member have a prism shape. 4. The method according to claim 3, wherein the prism is made of a transparent material, and the fixing surface of the fixing member and the reflecting surface of the reflecting member are end surfaces of the transparent material. 5. The hologram recording method according to claim 4, wherein the transparent body is a liquid contained in a solid frame. 6. The method according to claim 1, wherein at least one of the reflection surfaces is a flat surface. 7. The hologram recording method according to claim 1, wherein at least one of the reflection surfaces is a quadratic curved surface.