ヌルレンズ補正法による微小レンズの2次元複屈折分布計測

抄録

A birefringence in the next generation of DVD pickup lens is one of the important factors of evaluation. A precise measurement of birefringence is required because an astigmatic aberration by birefringence distribution causes degradation of pickup signal. A purpose of this paper is to construct two- dimensional measurement of birefringence on a pickup lens. A null lens method is proposed to prevent beam expansion by sample lens. Sixteen images captured by CCD camera are adopted to analyze both retardation and principal azimuth by local-sampling phase shifting.