Measurement of phase retardation of waveplate online based on laser feedback

Polarization flipping accompanying with intensity transfer between two eigenstates of one laser mode happens when waveplate is placed in external cavity. The position of polarization flipping of two eigenstates is a function of phase retardation of waveplate. Phase retardation of waveplate is measured through analyzing the position of polarization flipping of two eigenstates. The measurement accuracy of phase retardation is 0.22 degrees. A new structure of optical cement tray which can eliminate stress birefringence from optical cement process is invented. The accuracy of waveplate manufacture can be improved greatly based on the work of this article. (C) 2012 American Institute of Physics. [doi:10.1063/1.3673641]