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:
Jun. 29, 1993
Filed:
Mar. 30, 1992
Charles J Kramer, Rochester, NY (US);
Mehdi N Araghi, Webster, NY (US);
Holotek Ltd., Rochester, NY (US);
Abstract
Laser beam scanners having a polarization sensitive beam deflecting surface (specifically a monofacet nondisc plane diffraction grating (NPDG) monofacet deflector and a dual reflection monofacet polarization sensitive deflector that incorporates a polarizing beam splitter cube) achieve essentially 100% radiometric throughput efficiency while also achieving a scan beam intensity that stays constant over the total range of scan angles by using a circularly polarized incident beam and a quarter-wave retardation plate at the entrance aperture of the scanner assembly so that the quarter-wave plate rotates with the assembly. The quarter-wave plate has its optical axis oriented with respect to the incident beam so that it converts the incident circularly polarized beam into a linearly polarized beam having a polarization direction that maximizes the radiometric throughput efficiency of the scanner assembly. The polarization direction of the converted linearly polarized beam stays constant relative to the deflecting surface, as a result of using the circularly polarized incident beam and the quarter-wave plate which rotates with the deflecting surface.