Patent ID: 7155105
Filing Date: 2006-12-26
Classification: G02B,G02F

Abstract:
1. A method of controlling attenuation of an optical signal in a optical network, the method comprising: applying energy to a first heating element coupled to a first thermal gradient prism, wherein the first thermal gradient prism is made of a first thermally active medium; applying energy to a second heating element coupled to a second thermal gradient prism, wherein the second thermal gradient prism is made of a second thermally active medium; inputting the optical signal into the first thermal gradient prism; inputting the optical signal output from the first thermal gradient prism into the second thermal gradient prism; measuring strength of the optical signal output from the second thermal gradient prism; adjusting level of energy applied to the first heating element in response to the strength of the optical signal output from the second thermal gradient prism; and adjusting level of energy applied to the second heating element in response to the strength of the optical signal output from the second thermal gradient prism.