高精密滚转角测量干涉仪

现有的各种激光干涉仪可以方便地测量围绕垂直于直线位移方向的两个转角偏移，但是对于围绕运动轴的滚转角偏移，特别是对于大行程运动，缺乏有效的测量方法。针对各种高精密直线运动定位装置，设计一个新型的差分平面干涉仪，并采用一个楔面棱镜和楔面反射镜，组合成为一个几何空间对称四光路系统，构成新型的高精密滚转角激光干涉测量仪。它不需要与行程同长的大反射参考镜，但同样能实现高分辨率，而且简便实用，可以直接溯源米定义。试验证明，几何空间对称四光路滚转角干涉测量仪能够有效地排除其他自由度运动的干扰，利用它可以快速高效地测量各种精密直线位移运动的滚转角。使用普通的2π/360细分相位计，测量分辨率为1.1″，若使用2π/36 000的高精密细分相位计，滚转角的测量分辨率可达到0.01″。

High Precision Roll Angle Interferometer

Using of existing laser interferometer the two angular deviations, i.e. the rotations around the axes vertical to the displacement movement direction, can be already easily measured. But the rotation around the displacement movement axis(roll angle) , especially for large range movement, there has been no effective measurement method. Toward to high precision positioning stages, we have developed a high precision micro roll measurement interferometer, which uses a special differential plane mirror interferometer combining a wedge prism and a wedge reflector assembly. It does not need a large reference mirror, but it can quickly and efficiently measure the roll angle of each kind of precision linear positioning stages and achieve both high measurement resolution and practicability. Also it can be directly traced to meter definition without calibration. Experimental results show that the roll angle interferometer with such four optical symmetry paths can effectively eliminate the influences of other DOF motion. By using of normal phase meter with 2π/360 subdivision, the roll angle measurement resolution is about 1". By using of high precision phase meter with 2π/36 000 subdivision, the roll angle measurement resolution will reach 0.01".