Diffractive part

Dynamic information storage or retrieval – Specific detail of information handling portion of system – Radiation beam modification of or by storage medium

Reexamination Certificate

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Details

C369S112030, C369S044280, C369S044370

Reexamination Certificate

active

07602691

ABSTRACT:
A diffractive part for an optical scanning device is described. The device is for scanning a first information layer by means of a first radiation beam having a first wavelength and a first polarisation, a second information layer by means of a second radiation beam having a second wavelength and a second polarisation, and a third information layer by means of a third radiation beam having a third wavelength and a third polarisation. The first, second and third wavelengths differ from each other. The device includes a radiation source for supplying the first, second and third radiation beams, an objective lens system for converging the radiation beams on the respective information layer, and a diffractive part arranged in the optical path of the radiation beams. The diffractive part includes a first diffractive grating structure having a series of steps of predetermined height to introduce a phase change that is an integral multiple of 27E for both the second and third wavelengths but not the first wavelength, and a second diffractive grating structure having a series of steps of predetermined height to introduce a phase change that is an integral multiple of 27π for the first and third wavelengths but not the second wavelength.

REFERENCES:
patent: 5966364 (1999-10-01), Kamatani
patent: 6304541 (2001-10-01), Chang et al.
patent: 7433290 (2008-10-01), Komma
patent: 7522508 (2009-04-01), Nishioka et al.
patent: 2002/0051247 (2002-05-01), Jutte et al.
patent: 2002/0196726 (2002-12-01), Takeda
patent: 2003/0039033 (2003-02-01), Takeuchi et al.
patent: 2003/0064295 (2003-04-01), Yasuyuki et al.
patent: 2003/0179680 (2003-09-01), Park et al.
patent: 2005/0083562 (2005-04-01), Hendriks
patent: 1430219 (2003-07-01), None
patent: 0789355 (1997-08-01), None
patent: 0789355 (1997-08-01), None
patent: 2001209966 (2001-08-01), None
patent: 03056550 (2003-07-01), None
patent: 03060891 (2003-07-01), None
E Verstegen, et al: Photo Replication of Birefringent Phase Structures, Journal of Applied Physics, vol. 43, No. 7B, Jul. 2004, pp. 4772-4776.
G. Bouwhuis, et al: Principles of Optical Disc Systems, Adam Hilger, 1985, ISBN 085274-785-3, pp. 75-80.

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