HOLOGRAM INFORMATION RECORDING MEDIUM AND HOLOGRAM INFORMATION RECORDING/REPRODUCING DEVICE

• US 20090052300A1
• Filed: 02/15/2006
• Published: 02/26/2009
• Est. Priority Date: 02/28/2005
• Status: Active Grant

• Current Assignee: Dualitas Ltd. (Envisics, LLC)
• Original Assignee: ALPS Electric Company Limited (Alps Alpine Co., Ltd.)
• Inventors: Tokuchi, Naoyuki, Someno, Yoshihiro
• Granted Patent: US 7,907,494 B2
• Time in Patent Office: Days
• US Class Current: 369/103
• CPC Class Codes: G03H 1/26 Processes or apparatus specially adapted to produce multiple sub- holograms or to obtain images from them, e.g. multicolour technique
• CPC Class Codes: G03H 1/2645 Multiplexing processes, e.g. aperture, shift, or wavefront multiplexing
• CPC Class Codes: G03H 2001/186 Swelling or shrinking the holographic record or compensation thereof, e.g. for controlling the reconstructed wavelength G03H2001/0033, G03H2250/44 take precedence
• CPC Class Codes: G03H 2001/266 Wavelength multiplexing
• CPC Class Codes: G03H 2001/306 Tiled identical sub-holograms
• CPC Class Codes: G11B 19/046 Detection or prevention or problems due to temperature
• CPC Class Codes: G11B 33/1433 by reducing the effects of the thermal expansion
• CPC Class Codes: G11B 33/144 by detection, control, regulation of the temperature
• CPC Class Codes: G11B 7/0045 Recording G11B7/006, G11B7/0065 take precedence
• CPC Class Codes: G11B 7/0065 Recording, reproducing or erasing by using optical interference patterns, e.g. holograms
• CPC Class Codes: G11B 7/00772 on record carriers storing information in the form of optical interference patterns, e.g. holograms
• CPC Class Codes: G11B 7/083 relative to record carriers storing information in the form of optical interference patterns, e.g. holograms
• CPC Class Codes: G11B 7/126 Circuits, methods or arrangements for laser control or stabilisation

Abstract

[Object] To provide a hologram information recording medium and a hologram information recording/reproducing device capable of accurately reproducing data multiplexed on the recording medium irrespective of the influence of the external environment and so forth.

[Solving Means] In one recording area 31 of a recording medium 3, a plurality of the same information groups are recorded in substantially the same area with varied multi-parameters, in consideration of the expansion and the contraction of the recording medium 3. That is, a plurality of data groups A to D are recorded in the one recording area 31 of the recording medium 3, with a laser wavelength λ varied. Specifically, the data groups A to D are recorded in one recording area as three groups: a data group G₁ including data A₁, data B₁, data C₁, and data D₁; a data group G₂ including data A₂, data B₂, data C₂, and data D₂; and a data group G₃ including data A₃, data B₃, data C₃, and data D₃.

Claims

1-5. -5. (canceled)

6. A hologram information recording medium for performing recording thereon by irradiating the recording medium with signal light and reference light while varying a multi-parameter, and for reproducing information therefrom by using reproduction light diffracted by the reference light while varying the above multi-parameter, the hologram information recording medium characterized in that a plurality of hologram information groups including the same data are recorded by different multi-parameters in substantially the same area of the hologram information recording medium so as to allow the expansion and the contraction of the hologram information recording medium according to the temperature.

7. The hologram information recording medium described in claim 6, characterized in that the multi-parameter is the wavelength of the signal light or the reference light or the angle at which the recording medium is irradiated with the signal light or the reference light.

8. The hologram information recording medium described in claim 6, characterized in that each of the plurality of hologram information groups is recorded with index information which includes condition data in the recording of the hologram information group.

9. A hologram information recording device comprising:

a light source for emitting signal light and reference light;

an optical system for irradiating an information recording medium with the signal light and the reference light; and

multi-parameter control means for controlling a multi-parameter to perform multiplex recording of information on the information recording medium, the hologram information recording device characterized in that the multi-parameter control means records hologram information groups including the same data, a plurality of times, with different multi-parameters in substantially the same area of the information recording medium so as to allow the expansion and the contraction of the information recording medium according to the temperature.

10. The hologram information recording device described in claim 9, characterized in that each of the hologram information groups includes index information which includes temperature condition data in the recording of the hologram information group.

11. The hologram information recording device described in claim 9, characterized by comprising:

temperature detection means for detecting the temperature in the vicinity of the information recording medium; and

correction means for performing correction of the above multi-parameter in information reproduction on the basis of the temperature detected by the temperature detection means.

12. The hologram information recording device described in claim 9, characterized in that the multi-parameter is the wavelength of the signal light or the reference light or the angle at which the recording medium is irradiated with the signal light or the reference light.

13. A hologram information reproducing device comprising:

a light source for emitting reference light;

an optical system for irradiating an information recording medium with the reference light; and

multi-parameter control means for controlling a multi-parameter to reproduce hologram information multiplex-recorded on the information recording medium,

the hologram information reproducing device characterized in that the information recording medium is recorded with a plurality of hologram information groups including the same data, with different multi-parameters, in substantially the same area of the information recording medium so as to allow the expansion and the contraction of the information recording medium according to the temperature, and

that the multi-parameter control means controls the multi-parameter of the reference light to correspond to one of the plurality of hologram information groups recorded with the different multi-parameters.

14. The hologram information reproducing device described in claim 13, characterized in that the plurality of hologram information groups include index information which includes temperature condition data in each of the recordings of the hologram information groups, and that the multi-parameter control means controls the multi-parameter in information reproduction on the basis of the index information.

15. The hologram information recording/reproducing device described in claim 13, characterized by comprising:

temperature detection means for detecting the temperature in the vicinity of the information recording medium; and

correction means for performing correction of the multi-parameter in information reproduction on the basis of the temperature detected by the temperature detection means.

16. The hologram information reproducing device described in claim 13, characterized in that the multi-parameter is the wavelength of the reference light or the angle at which the recording medium is irradiated with the reference light.

17. A hologram information recording method characterized by comprising:

a step of preparing an information recording medium; and

a step of recording hologram information groups including the same data, a plurality of times, in substantially the same area of the above information recording medium while varying a multi-parameter of signal light and reference light so as to allow the expansion and the contraction of the recording medium according to the temperature.