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:
Apr. 20, 2004
Filed:
Dec. 10, 2001
Bernard P. Masterson, Louisville, CO (US);
Henrik Hofvander, Boulder, CO (US);
Melles Griot, Inc., Carlsbad, CA (US);
Abstract
A low noise laser includes a birefringent gain crystal arranged so that polarization is not constant within the gain crystal. The gain crystal and an intracavity optical element each have a nonzero polarization retardance. The total single-pass retardance is approximately equal to an odd multiple of one-half wave; for example each may provide one quarter wave retardance. In one embodiment the optical element comprises a nonlinear crystal situated within the laser cavity for Type II frequency doubling. The principal crystal axis of the gain crystal is offset from the principal axis of the nonlinear crystal at an offset angle for example about 45°. In one embodiment a gain crystal and frequency-doubling crystal are coupled together to form a monolithic laser component. An alternative embodiment is described in which the optical element comprises a quarter-wave plate and the laser output includes substantially two linear polarizations at the fundamental wavelength.