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:
Jan. 31, 2012
Filed:
May. 11, 2007
Tsuguhiro Korenaga, Osaka, JP;
Takamasa Ando, Osaka, JP;
Masa-aki Suzuki, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A diffractive imaging lensincludes a surface on which a diffraction grating pattern is formed. The diffraction grating pattern is formed of a plurality of steps formed concentrically with an optical axis () at a center. The diffraction grating pattern is formed such that a first portion where amounts (di) of the steps are substantially the same in a radial direction of concentric circles and a second portion, outside of the first portion, where amounts (di) of the steps decrease with distance from the optical axisare provided, or such that the amounts (di) of the steps decrease with distance from the optical axisover the entire diffraction grating pattern.