JPH0428107B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to an improvement in a method for manufacturing a hologram disk.

(b) Background of the technology A hologram sensitive material is formed on a transparent substrate such as a glass substrate, and a predetermined pattern of laser light is irradiated onto the hologram sensitive material to form a predetermined pattern of hologram. After cutting the glass substrate into a donut-shaped disk, the hologram disk is attached to a rotating shaft that rotates at a predetermined rotational speed, and while the hologram disk is rotated, a laser beam is irradiated onto the hologram disk to create a hologram circle. Hologram disks, which scan and read optical information stored on a board, have recently been used in POS terminals and the like because they are smaller than magnetic disk devices and can process a large amount of information at high speed.

(c) Prior Art and Problems The conventional manufacturing method of such a hologram disk will be explained using FIGS. 1 to 2.

As shown in the figure, a hologram sensitive material such as Kodak's product name (Kodak120-01) is coated on a transparent glass substrate 1, and then a spherical wave or plane wave laser is emitted from He-Ne laser light sources 2 and 3. Light is irradiated onto the hologram sensitive material through a photomask 4, and interference fringes are formed by interference of the spherical waves and plane waves, thereby forming a hologram facet 5 in a predetermined pattern.

Thereafter, the glass substrate on which the hologram facet has been formed in this manner is cut into a donut-shaped disk having a circular hole formed in the center, as shown in FIG. 2, to form a hologram disk 6.

Thereafter, the circular machined hole in the center of the hologram disk thus formed is placed on the rotation axis of a hologram disk device that rotates at high speed, and while the hologram disk is rotating at high speed, a laser beam is applied to the disk from an Ar laser light source. The optical information in the hologram disk is read out while being scanned.

By the way, the disk is installed on the rotary table of the hologram disk device so that the center position of the rotation axis matches the predetermined position of the pattern made of the hologram, and the laser beam is irradiated onto the hologram disk and emitted. It is necessary to improve the scanning position accuracy of the emitted light by regulating the position of the emitted light to a predetermined position.

Conventionally, as a method of matching the center of such a rotation axis with a predetermined position of a hologram pattern,
A hologram disk is attached to the rotating shaft, a laser beam is irradiated onto the hologram disk, the emitted light is detected, and the position of the disk plate is adjusted so that the emitted light is at a predetermined beam position. If this method is used, the disadvantage is that the adjustment takes too much time.

Furthermore, when a hologram pattern is formed on a rectangular glass substrate and the glass substrate is cut into a donut-shaped disk, the center of the circular hole cut inside the donut shape and the predetermined position of the hologram pattern are It is necessary that they match, but
In this case, a convex-shaped protruding part is provided at a predetermined position on the rotating shaft, a concave-shaped recess is provided at a predetermined position in the hole of the hollowed out disk, and the protruding part and the recess are butted together for accuracy. However, this method has the disadvantage that the processed center of the disk does not match the center position of the pattern with high accuracy.

(d) Object of the Invention The present invention eliminates the above-mentioned drawbacks and improves the center position of a hologram pattern and the center position of a processed hole in the center of a donut-shaped hologram disk, or the predetermined position of a hologram pattern and the rotation of a hologram disk. The object of the present invention is to provide a novel method for manufacturing a hologram disk in which the centers can be easily aligned.

(e) Structure of the Invention In order to achieve the above object, the method for manufacturing a hologram disk of the present invention includes depositing a material to be a hologram sensitive material on a light-transmitting substrate, and then applying a predetermined amount to the hologram sensitive material. In manufacturing a hologram disk, the transparent substrate is cut into a donut-shaped disk after irradiating a patterned laser beam to form interference fringes on the hologram sensitive material to form a hologram. After forming a hologram sensitive material on a photosensitive substrate, the substrate is placed on a rotating stage of a hologram disk device, and while rotating the substrate, the outermost periphery and the outermost circumference of the donut-shaped disk to be formed are By irradiating a hologram photosensitive material formed on the inner circumference with a predetermined pattern of laser light and exposing the photosensitive material, the center position of the rotation axis and the predetermined position of the hologram pattern can be determined. The present invention is characterized in that alignment marks are formed for matching, and the translucent substrate is cut into a donut-shaped disc using the alignment marks.

(f) Embodiment of the Invention An embodiment of the present invention will be described below in detail with reference to the drawings.

3 and 4 are perspective views for explaining the hologram manufacturing method of the present invention.

First, a hologram sensitive material made by Kodak Co., Ltd. under the trade name (Kodak 120-01) is coated on the entire surface of a transparent rectangular glass substrate 11, and then the substrate is placed on a rotation stage (not shown) of a hologram disk device.

Next, while rotating the rotary stage, the hologram sensitive material is exposed in a cross shape using a light emitting diode (not shown) as a light source through photomasks 12 and 13 that transmit light in a cross shape. At this time, the light 14 emitted through the photomask 12 is emitted at a predetermined pitch along the outer periphery of the rotation axis of the stage of the hologram disk device. Further, the light emitted through the photomask 13 is emitted at a predetermined pitch along the outer periphery of the disk of the hologram disk to be formed.

After forming a cross-shaped alignment mark in a predetermined pattern in this way, the He-Ne laser light source 1 is passed through the hologram facet forming mask pattern 15.
A hologram facet 18 having a predetermined pattern is formed by irradiating a laser beam using 6 and 17.

Next, the substrate on which the hologram facet 18 and the cross-shaped alignment mark were formed was developed and fixed using a developer and a fixer, and then tape was applied only to the area where the alignment mark was formed, and then bromine was applied. (Br ₂ ) gas is used to bleach the hologram facets. In this way, silver (Ag) is precipitated in the cross mark and stands out clearly, and silver bromide (AgBr) is precipitated in the hologram facet part, making it almost transparent.

Next, the substrate is cut into a disk shape along the cross mark formed on the outer periphery of the hologram facet.

Next, as shown in FIG. 4, the hologram disk 21 thus formed is aligned with the alignment mark 23
24 is placed on the rotating shaft 22 of the stage of the hologram disk device while being inspected with a microscope 25.

Note that the alignment marks 23 and 24 are made to correspond to each other, and a reference mark is also provided on the surface of the rotating shaft 22 in advance, and by aligning the positions of this reference mark and alignment mark 23, The center position of the processed hole provided in the substrate and the center position of the hologram pattern come to match.

(g) Effects of the Invention As described above, according to the method of the present invention, the hologram disk disk is placed on the rotating stage with the center position of the pattern and the center position of the processed hole of the hologram disk matching, The advantage is that a highly reliable hologram disk device can be obtained.

[Brief explanation of drawings]

1 and 2 are perspective views showing a conventional method for manufacturing a hologram disk, and FIGS. 3 and 4 are perspective views showing an embodiment of the method for manufacturing a hologram disk according to the present invention. In the figure, 1 and 11 are glass substrates, 2, 3, 1
6, 17 are He-Ne laser light sources, 4, 15 are masks, 5, 18 are hologram facets, 6, 21
12 and 13 are hologram disks, 12 and 13 are alignment mark forming masks, 14 is a pattern of emitted light, 22 is a rotating shaft, 23 and 24 are alignment marks, and 25 is a microscope.

Claims (1)

[Scope of Claims] 1. After a material to be a hologram sensitive material is adhered and formed on a transparent substrate, a predetermined pattern of laser light is irradiated to the hologram sensitive material to form interference fringes on the hologram sensitive material. After forming a hologram by providing a hologram, in the production of a hologram disk, the transparent substrate is cut into a donut-shaped disk, and after forming a hologram sensitive material on the transparent substrate, The substrate is placed on a rotating stage of a hologram disk device, and as the substrate is rotated, the hologram photosensitive material that has been deposited on the outermost and innermost positions of the donut-shaped disk to be formed is , by irradiating and exposing the sensitive material with a predetermined pattern of laser light, an alignment mark is formed that matches the center position of the rotation axis with a predetermined position of the hologram pattern, and the alignment mark is formed based on the alignment mark. A method for manufacturing a hologram disk, which comprises cutting a transparent substrate into a donut-shaped disk.