Optical: systems and elements – Polarization without modulation – By relatively adjustable superimposed or in series polarizers
Reexamination Certificate
2008-01-22
2008-01-22
Lavarias, Arnel (Department: 2872)
Optical: systems and elements
Polarization without modulation
By relatively adjustable superimposed or in series polarizers
C359S900000, C359S352000
Reexamination Certificate
active
07321465
ABSTRACT:
A numerical optimizing method serves to reduce harmful effects caused by intrinsic birefringence in lenses of a fluoride crystal material of cubic crystal structure in an objective, particularly a projection objective for a microlithography system. Under the optimizing method, an optimizing function which takes at least one birefringence-related image aberration into account is minimized. The birefringence-related image aberration is determined from a calculation for a light ray passing through the fluoride crystal lenses. To the extent that the birefringence-related image aberration is a function of parameters of the light ray, it depends only on geometric parameters of the light ray. The numerical optimizing method is used to produce objectives in which an optical retardation as well as an asymmetry of the optical retardation are corrected. The lenses are arranged in homogeneous groups, where each homogeneous group is corrected for the optical retardation asymmetry.
REFERENCES:
patent: 6788389 (2004-09-01), Fujishima et al.
patent: 7126765 (2006-10-01), Krahmer et al.
patent: 7145720 (2006-12-01), Krahmer et al.
patent: 2004/0070744 (2004-04-01), Ozawa
patent: 2005/0018277 (2005-01-01), Ozawa
patent: 2005/0018278 (2005-01-01), Ozawa
patent: 2005/0200966 (2005-09-01), Totzeck et al.
patent: 2006/0171020 (2006-08-01), Krahmer et al.
patent: 101 23 725 (2002-11-01), None
patent: 101 33 841 (2003-02-01), None
patent: 1 0006 373 (2000-06-01), None
patent: 1 063 684 (2000-12-01), None
patent: 01 50171 (2001-07-01), None
patent: WO 200231570 (2002-04-01), None
patent: 02 093209 (2002-11-01), None
patent: 03 077007 (2003-09-01), None
Burnett et al., “Intrinsic birefringence in calcium fluoride and barium fluoride,” Physical Review B—The American Physical Society, vol. 64, 241102(R), Nov. 29, 2001.
Burnett et al., “The trouble with calcium Fluoride,” Spie's OE Magazine—Special focus section, pp. 23-25, Mar. 2002.
Gruner Toralf
Kamenov Vladimir
Totzeck Michael
Carl Zeiss SMT AG
Fish & Richardson P.C.
Lavarias Arnel
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