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:
Sep. 22, 1987
Filed:
Jun. 11, 1985
Robert C Harshaw, Dallas, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A tunable multiline/multiband laser includes a partial reflecting mirror, a gain control, a diffraction grating means, and a reflective mirror means. The reflective mirror means includes in a first embodiment a fabricated mirror which allows for any number of predetermined lines and combinations, which a second embodiment replaces the fabricated mirror with a material that is capable of changing its reflectivity upon changing its thermodynamic phase state. The diffraction grating means includes a grating and a lens to spatially separate initially parallel rays of different wavelengths originating from the gain cell and project the spectrum onto the surface of the mirror means. The mirror means includes a mirror constructed to normalize the round trip gain to each frequency component. The normalization is accomplished by proper choice of reflectivities at the focal point of each wavelength upon the mirror. The mirror consists of a nonreflecting substrate having either a plurality of equal size reflective areas selectively coated to vary their reflectivity or of different sizes to vary their reflectivity to equalize the round trip gain for lasing. The reflective areas can also be formed using a thin film of phase transition material and a heating means such as an electron beam gun or heating elements formed in the surface of a silicon substrate polished to optical flatness.