A real-time measurement method for the retardation of an eighth-wave plate is proposed. The collimated laser beam is split using a Clan Taylor polarizer with two side escape windows. The reflected sub-beam is detected...A real-time measurement method for the retardation of an eighth-wave plate is proposed. The collimated laser beam is split using a Clan Taylor polarizer with two side escape windows. The reflected sub-beam is detected using a detector, whereas the transmitted sub-beam passes through the quarter-wave plate and the eighth-wave plate of interest. Then, it is reflected by the mirror and passes reversely through the eighth- and quarter-wave plates. Finally, it is analyzed using the Clan Taylor polarizer and detected using another detector. With two detection signals, the retardation is resolved and found to be independent of the fast-axis direction, initial intensity, and circuit parameters. In the experiment, a crystal quartz sample is measured at different fast-axis angles. The standard deviation of the retardation is 0.9°. The usefulness of the method is verified.展开更多
基金supported by the National Science and Technology Major Project of China (No. 2011ZX02402)the International Science and Technology Cooperation Program of China (No. 2011DFR10010)State Key Laboratory of Applied Optics, China (No.Y1Q03FQK06)
文摘A real-time measurement method for the retardation of an eighth-wave plate is proposed. The collimated laser beam is split using a Clan Taylor polarizer with two side escape windows. The reflected sub-beam is detected using a detector, whereas the transmitted sub-beam passes through the quarter-wave plate and the eighth-wave plate of interest. Then, it is reflected by the mirror and passes reversely through the eighth- and quarter-wave plates. Finally, it is analyzed using the Clan Taylor polarizer and detected using another detector. With two detection signals, the retardation is resolved and found to be independent of the fast-axis direction, initial intensity, and circuit parameters. In the experiment, a crystal quartz sample is measured at different fast-axis angles. The standard deviation of the retardation is 0.9°. The usefulness of the method is verified.