液晶光栅相控阵偏转波前测量方法研究

为了测试相控阵激光雷达的关键器件液晶光栅相控阵的偏转光束波前,以监控和评价雷达扫描光束的质量,采用带有光束变向功能的径向剪切干涉测量方法,进行了理论分析和实验验证,取得了口径为10mm×10mm的偏转波前测试系统与商用WYKO干涉仪的比对测试数据。两种仪器对同一块平面样板测出的波前之差的峰谷值小于λ/20,均方根值小于λ/200,还取得了实测液晶光栅相控阵不同偏转光束的波前数据。结果表明,该方法可以对液晶光栅相控阵的偏转波前进行高精度测试。

Study about deflection wavefront measurement approach of liquid-crystal grating phased array

In order to test deflection wavefront of liquid-crystal grating phased array, a key component in phased array laser radar, and monitor and evaluate the quality of radar scanning beams, a radial shearing interference measurement technology with direction changing function was adopted and theoretical analysis and experimental verification about this method were carried out. Test data were obtained with a 10mm×10mm aperture deflection wavefront tester and a commercial WYKO interferometer respectively. The difference of test results is less than λ/20 for peak-valley value and less than λ/200 for root mean square(RMS) value for the same plane optical element. Deflection wavefront of liquid-crystal grating phased array was measured. The experimental results show that this method can measure deflection wavefront of the liquid-crystal grating phased array with high precision.