Patent ID: 7826502
Filing Date: 2010-11-02
Classification: G02F

Abstract:
1. A circuit for generating a low noise short wavelength optical signal, comprising: a laser for providing a first optical signal having a first wavelength longer than a second wavelength of the short wavelength signal; a frequency converting element positioned to receive the first optical signal from the laser and for converting the first optical signal into the short wavelength signal; a feedback circuit for detecting a portion of the short wavelength signal, for determining a level of noise in the detected portion of the short wavelength signal, and for adjusting temperature of the frequency converting element upward one or more temperature increments and downward one or more temperature increments continuously so as to lessen noise in the short wavelength signal, wherein said adjustments upward and downward in temperature are based on a current determined level of noise in the detected portion of the short wavelength signal; and a control circuit for maintaining the power level of the short wavelength signal to be at a constant value while the feedback circuit lessens noise in the short wavelength signal.