Full-Field Measurements in the Principal Axis and Phase Retardation of Linear Birefringent Materials in Full-Scale Range

• Main Authors: Hsu Shan, 單煦
• Other Authors: Yu-Lung Lo
• Format: Others
• Language: en_US
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/27839303098080459795

碩士 === 國立成功大學 === 機械工程學系碩博士班 === 96 === In this paper, two novel heterodyne interferometers designed for measuring the principal axis and phase retardation of the linear birefringent materials in full-field are proposed. By using a complex programmable logic device (CPLD) and a charge-coupled device (CCD), integrating buckets with multiple frames are achieved. In our first systems, we can achieve to measure the principal axis and phase retardation in full field simultaneously, but the dynamic range of phase retardation measurement is only up to 90° and that of the principal axis angle measurement is up to 180° in the full range. The second system is designed to achieve the full-scale and full-field measurement by sequentially measurement. The dynamic range of the principal axis and phase retardation of sequential measurement is both in full-scale range. In the two measurement systems, the noises induced by environmental disturbance and direct current component of the output light intensity can be reduced because of the elimination in the algorithm. Also, the method we proposed can determine the principal axis of the uni-axial material is fast axis or slow axis from the configuration arrangement.