Patent ID: 8508841

Claim:
A light conversion module, comprising: a coupler combining two light beams to form a combined light beam; a nonlinear crystal arranged to receive the combined light beam, configured to include a plurality of poling regions for performing successive nonlinear frequency mixing processes; a first optical device configured to focus the combined light beam onto the nonlinear crystal; a first moving stage carrying the nonlinear crystal and configured for moving the nonlinear crystal for an adjustment of a focus position of the combined light beam on the nonlinear crystal; an optical detector configured for measuring a power level of a light beam from the nonlinear crystal for the adjustment of the focus position of the combined light beam on the nonlinear crystal; a splitting mirror for directing a portion of the light beam to the optical detector; a second optical device for focusing the light beam from the nonlinear crystal and a second moving stage carrying the second optical device for adjusting a focus point of the second optical device; a heating element for heating the nonlinear crystal; a temperature sensor adjacent to the nonlinear crystal for controlling the temperature of the nonlinear crystal; and a position sensor for sensing a position of the first moving stage; wherein the nonlinear crystal comprises a first poling region for a sum frequency generation process, a second poling region for a second harmonic generation process, and a third poling region for a sum frequency generation process, wherein the first, second, and third poling regions are arranged in a cascading manner.