Hologram recording medium

Abstract

A hologram recording medium includes a stack of at least a lower transparent substrate, a recording layer made of a photocurable organic material, and an upper transparent substrate, wherein a spacer for keeping a thickness of the recording layer is dispersed and disposed in the inside of the recording layer in a direction of a principal plane of the hologram recording medium.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view to show a configuration of a first embodiment of a hologram recording medium according to an embodiment of the invention.

FIG. 2 is a sectional view to show a variation configuration (1) of the first embodiment of the hologram recording medium according to an embodiment of the invention.

FIG. 3 is a sectional view to show a variation configuration (2) of the first embodiment of the hologram recording medium according to an embodiment of the invention.

FIG. 4 is a sectional view to show a configuration of a second embodiment of a hologram recording medium according to an embodiment of the invention.

FIG. 5 is a sectional view to show a variation configuration (1) of the second embodiment of the hologram recording medium according to an embodiment of the invention.

FIG. 6 is a sectional view to show a variation configuration (2) of the second embodiment of the hologram recording medium according to an embodiment of the invention.

FIG. 7 is a sectional view to show a configuration of a third embodiment of a hologram recording medium according to an embodiment of the invention.

FIG. 8 is a sectional view to show a variation configuration of the third embodiment of the hologram recording medium according to an embodiment of the invention.

FIG. 9 is an outline view to show a configuration example of an exposure optical system of a hologram recording medium.

Claims

1. A hologram recording medium comprising a stack of at least a lower transparent substrate, a recording layer made of a photocurable organic material, and an upper transparent substrate, wherein a spacer for keeping a thickness of the recording layer is dispersed and disposed in the inside of the recording layer in a direction of a principal plane of the hologram recording medium.

2. The hologram recording medium according to claim 1, wherein the spacer is a fine particle.

3. The hologram recording medium according to claim 1, wherein the spacer is a projection provided on a surface of the lower transparent substrate and/or the upper transparent substrate.

4. The hologram recording medium according to claim 1, wherein an area occupation rate of the spacer in a region of the principal plane of the recording layer is not more than 13%.

5. The hologram recording medium according to claim 1, wherein the spacer is at least transparent against light which is used during recording or reproduction of the hologram recording medium, anda difference in refractive index between the spacer and the recording layer falls within 20%.

6. The hologram recording medium according to claim 1, wherein the spacer has a scattering of length in a thickness direction of the recording layer falling within 10%.

7. The hologram recording medium according to claim 1, wherein each of the lower substrate and the upper substrate is made of a polycarbonate or polyethylene terephthalate.