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. 24, 1991
Filed:
Dec. 07, 1990
Harold M Epstein, Columbus, OH (US);
Jeffrey L Dulaney, Hilliard, OH (US);
Battelle Memorial Institute, Columbus, OH (US);
Abstract
Apparatus 10 (FIG. 2) for providing coherent radiation 12 that is not polarized, comprises a laser pump cavity 14 for providing a beam of unpolarized coherent radiation 12 in a predetermined first direction (upward); a polarizer 15, for breaking down the radiation 12 into two linearly polarized orthogonal components, 12A,12B, transmitting one component 12A through it in the first (upward) direction, and reflecting the other component 12B from it in a second direction (upper right); mirrors 17,18,19 for reflecting the component 12A along a first closed path 15,17,18,19,15 (clockwise) that ends in directing it back to the polarizer 15 in a third direction (lower left), opposite to the second direction, and for reflecting the component 12B along a second closed path 15,19,18,17,15 (counterclockwise) opposite to the first closed path 15,17,18,19,15, that ends in directing it back to the polarizer 15 in a fourth direction (downward), opposite to the first direction; a Q-switch 16 (for pulsed radiation) or a quarter wave plate 23 (for continuous wave radiation) in the closed paths 15,19,18,17,15; 15,17,18,19,15 for retarding each component 12A,12B of the radiation by a predetermined fraction of a wavelength, so that a substantial fraction of each component 12A,12B is transformed into the opposite component 12B,12A before reaching the polarizer 15; so that each transformed component is directed from the polarizer 15 in the fourth (downward) direction to the laser pump cavity 14 to maintain oscillation therein; and so that the fraction of each component 12A,12B that remains not transformed is directed from the polarizer 15 in the third direction (lower left); and thus so that the two last mentioned components 12A,12B combine to form a beam 12T of unpolarized useful output radiation E.sub.out that is directed in the third direction (lower left).