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. 19, 1985
Filed:
Feb. 17, 1983
William W Durand, Edina, MN (US);
Anil K Jain, New Brighton, MN (US);
Ronald E Peterson, Shoreview, MN (US);
Honeywell Inc., Minneapolis, MN (US);
Abstract
A tunable Fabry-Perot filter device including at least three low index substrates having a refractive index less than 2.4 and mounted in parallel relationship so as to present two pairs of facing sides to each other in an optical path and a high index, non-metallic or non-absorbing coating having a refractive index of at least 4.0, the high index coating being placed on the facing sides of each of said low index substrates with the thickness of the coating on at least one of the pairs of facing sides being less than the thickness of the coating on the other of the pairs of facing sides, and spacer means for mounting said low index substrates and adjusting the distance between said facing sides. Preferred substrates are potassium halides, cesium halides, and zinc selenide. High index, non-metallic or non-absorbing coatings are preferably from the group of lead telluride, bismuth telluride, germanium telluride and germanium. A high index coating normally has an optical thickness less than or equal to one-half of the minimum wavelength of light to be transmitted through the device. In a preferred embodiment, the spacer means is adapted to adjust one of said pairs of faces to pass the desired wavelength and the other of said pairs of faces is adjusted to pass a wide band width less than the separation between the multiple anharmonic bands. In another preferred embodiment, the spacer means is adapted to adjust one of said pairs to transmit a desired wavelength and the other of said pairs of faces is adjusted to transmit one of the multiple anharmonic bands at the desired wavelength such that only the desired wavelength is precisely tuned at said pairs.