Laminated wave plate and optical pickup using the same

Details Laminated wave plate and optical pickup using the same Laminated wave plate and optical pickup using the same

2007-12-11

2010-02-16

Young, Wayne R (Department: 2627)

Dynamic information storage or retrieval

Specific detail of information handling portion of system

Radiation beam modification of or by storage medium

C369S112020, C359S483010

Reexamination Certificate

active

07664002

ABSTRACT:
A conventional broadband quarter-wave plate has not completely solved the wavelength dependence and has different efficiencies of shifting the phase by 90° depending on the wavelengths, and therefore has a problem that it cannot fulfill the strict specifications on the optical characteristics which are demanded of a wave plate from a viewpoint of the optical efficiency and the like in an optical pickup device compatible with a plurality of different wavelengths. To provide a wave plate which completely functions as a quarter-wave plate with respect to a plurality of different wavelengths and an optical pickup using that wave plate to solve the problem, the present invention provides a laminated wave plate, wherein a wave plate with a phase difference α and a wave plate with a phase difference β with respect to monochromatic light with a wavelength λ are laminated in such a way that directions of optical axes of said plates intersect each other, so that the laminated wave plate, as a whole, functions as a quarter-wave plate, and which is characterized in that a relationship between the α and the β satisfies the following formulas:in-line-formulae description="In-line Formulae" end="lead"?(3/2)×π≠α−2×π×(m−1)in-line-formulae description="In-line Formulae" end="tail"?in-line-formulae description="In-line Formulae" end="lead"?π≠β−2×π×(n−1),in-line-formulae description="In-line Formulae" end="tail"?wherein: each of m and n is a positive integer.

REFERENCES:
patent: 5327270 (1994-07-01), Miyatake
patent: 5579138 (1996-11-01), Sannohe et al.
patent: 6504811 (2003-01-01), Morimoto
patent: 6580674 (2003-06-01), Nishiyama et al.
patent: 6873588 (2005-03-01), Mizuno et al.
patent: 6917576 (2005-07-01), Nishiyama et al.
patent: 2002/0159007 (2002-10-01), Suzuki et al.
patent: 2003/0123371 (2003-07-01), Nishiyama et al.
patent: 2004/0114494 (2004-06-01), Mizuno et al.
patent: 2004/0120044 (2004-06-01), Kreuzer
patent: 2004/0165518 (2004-08-01), Horimai et al.
patent: 2004/0208111 (2004-10-01), Hayashi et al.
patent: 2004/0257961 (2004-12-01), Nishi et al.
patent: 0 916 989 (1999-05-01), None
patent: 1 126 291 (2001-08-01), None
patent: 3174367 (1993-04-01), None
patent: 10-68816 (1998-03-01), None
patent: 10-068816 (1998-03-01), None
patent: 10-177737 (1998-06-01), None
patent: 10-214431 (1998-08-01), None
patent: 2000-276766 (2000-10-01), None
patent: 2002-276766 (2000-10-01), None
patent: 2001-4841 (2001-01-01), None
patent: 2001-101700 (2001-04-01), None
patent: 2001-184695 (2001-07-01), None
patent: 2001-307368 (2001-11-01), None
patent: 2001-344800 (2001-12-01), None
patent: 2002-14228 (2002-01-01), None
patent: 2002-117571 (2002-04-01), None
patent: WO 01/16627 (2001-03-01), None
J.M. Beckers, “Achromatic Linear Retarders”, Apr. 1971,Applied Optics, vol. 10, No. 4, pp. 973-975.

Affiliated with

Also associated with

Rating

Laminated wave plate and optical pickup using the same does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Laminated wave plate and optical pickup using the same, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Laminated wave plate and optical pickup using the same will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-4229704