The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 25, 2012
Filed:
Nov. 29, 2007
Kenichi Watatani, Itami, JP;
Keiji Fuse, Osaka, JP;
Yutaka Kobayashi, Itami, JP;
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
A condensing optical system having a condensed light spot with a small size and a large focal depth without causing a problem of a decrease in intensity of the condensed light spot or discontinuity of an intensity distribution in front and rear areas of a focal position is provided. The condensing optical system that condenses a laser beam generated by a laser source at a predetermined focal length is designed to satisfy Expressions (a) to (d), thereby producing 3rd and 5th spherical aberrations:||≧0.1λ or ||≧0.05λ,  (a)≧3 or<1,  (b)||<1.4λ, and  (c)||<0.5λ,  (d)where λ is a wavelength, Zis an 8th coefficient of coefficients of the Zernike fringe polynomial of wavefront aberration corresponding to a 3rd order spherical aberration, and Zis a 15th coefficient of the coefficients of the Zernike fringe polynomial of wavefront aberration corresponding to a 5th spherical aberration.