摘要
为了补偿激光外差干涉纳米测量中的非线性误差,提出了一种减小非线性误差的一次谐波方法。基于全反射理论分析了镀膜实体角锥棱镜反射光偏振特性,并由此推导出角锥棱镜反射光偏振特性及测量角锥棱镜以其运动方向为轴线的轴向旋转对激光外差干涉非线性误差一次谐波的影响模型。理论分析表明,测量角锥棱镜以其运动方向为轴线的轴向旋转会减小非线性误差一次谐波,当测量角锥棱镜轴向旋转97°时,可使非线性误差一次谐波达到最小,约为原有非线性误差一次谐波分量的1/20倍。当激光器出射的两束线偏振光存在6°非正交误差时,镀膜实体测量角锥棱镜轴向旋转角度从0°增加到97°,非线性误差一次谐波由5.30 nm减小到0.30 nm。
To compensate of the nonlinearity error of heterodyne interferometers in nanometer measurement, a method for reducing the first harmonic nonlinearity is proposed. Based on the total reflection theory, polarization properties of coated corner-cube retroreflector are analyzed. Then, the effect on the first-harmonic nonlinearity by the polarization properties of reflected light of the cube-corner retroreflector and axial rotation in the motion direction of the measurement cube-corner retroreflector is derived. The simulation results show that the first harmonic nonlinearity is reduced by the axial rotation of the cube-corner retroreflector. When the axial rotation angle is 97°, the first harmonic nonlinearity is the smallest, which is about 0.05 times smaller than the original. When the nonorthogonal error of the two linearly polarized beams is 6°, and the axial orientation rotation angle increases from 0° to 97°, the first harmonic nonlinearity is reduced from 5.30 to 0.30 nm.
出处
《光学学报》
EI
CAS
CSCD
北大核心
2007年第6期1027-1030,共4页
Acta Optica Sinica
关键词
光电子学
外差干涉
非线性误差
角锥棱镜
一次谐波
optoelectronics
heterodyne interference, nonlinear error
cube-corner retroreflector
first harmonic
