Patent ID: 6864986
Filing Date: 2005-03-08
Classification: G01M,G02F

Abstract:
1. A method of measuring the operation of an optical modulator comprising the steps of: (a) directing a light beam having a variable beam frequency upon said optical modulator; (b) causing said modulator to modulate said light beam with a modulation signal, and thereby produce a modulated light beam containing a carrier component corresponding to said variable beam frequency and a sideband component corresponding to the difference between the frequency of said carrier component and the frequency of said modulation signal; (c) simultaneously varying the frequency of said variable beam frequency light beam and the frequency of said modulation signal, in accordance with the same variation characteristic, so that said difference between the frequency of said carrier component and the frequency of said modulation signal varies in accordance with said same variation characteristic; and (d) detecting the variation in said difference between the frequency of said carrier component and the frequency of the modulation of said light beam resulting from step (c).