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. 31, 1996
Filed:
May. 31, 1995
Applicant:
Inventors:
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04N / ;
U.S. Cl.
CPC ...
348340 ; 359356 ; 359342 ;
Abstract
An optical low-pass filter includes an optical member formed of a material capable of absorbing light in a particular wavelength range, e.g., an infrared range. The optical member has a plurality of ridge-like portions formed on at least one surface thereof at a predetermined pitch. The ridge-like portions comprise a phase type diffraction grating which has a low-pass filtering effect with respect to bundles of optical transmission rays passing therethrough.