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:
Nov. 17, 1992
Filed:
Mar. 06, 1991
Daniel K Negus, La Honda, CA (US);
Bernard J Couillaud, Palo Alto, CA (US);
Coherent, Inc., Palo Alto, CA (US);
Abstract
A birefringent filter ('BRF') unit, for use in the cavity of a tunable pulsed laser generating ultrashort pulses, including means for suppressing satellite pulses resulting from surface reflections. In one preferred embodiment, the inventive BRF has substantially parallel front and back surfaces, and is cut so that its optical axis is not parallel to its front surface. For example, the inventive BRF may be a quartz crystal having a thickness of 3 mm, with its optical axis oriented at an angle substantially equal to 50 degrees from the plane of its front surface. In a second preferred embodiment, the inventive BRF includes a relatively thick, non-birefringent component coupled with index matching material to a relatively thin birefringent component. In a third preferred embodiment, the inventive BRF includes a pair of thick birefringent components designed so that the ordinary ray of the first component becomes the extraordinary ray of the second component. In this third embodiment, the two components preferably have substantially equal birefringence N, and differ in thickness by an amount W chosen so that the overall optical phase shift induced by the inventive BRF is substantially equal to the optical phase shift induced by a conventional single-component BRF having thickness W and birefringence N.