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:
Aug. 06, 2002
Filed:
Dec. 23, 1999
Stephen J. Borza, Ottawa, CA;
Activcard Ireland, Limited, Dublin, IE;
Abstract
An optical imaging device such as a fingerprint imager has a prism or another light transmitting element, a light source for illuminating a finger placed on the prism, and a CCD image sensor for receiving a light beam reflected from the finger-contacted surface. A modified optical lens is used to focus and redirect the reflected light beam. The lens has a relatively small reflective coating in the middle of its back surface, the reflective coating constituting an optical iris. The modified lens is effective to partly correct for peripheral aberration, perspective distortion and depth-of-field image distortion of the device and gives rise to a compact design of the device.