【摘要】 为便捷地定量检测大口径光学元件面形,运用数字刀口检测技术,把传统刀口仪与CCD图像采集处理、计算机辅助计算相结合,构成数字刀口仪。采用图像处理来确定阈值对应的刀口位置,引入PSD来描述频域信息。对125mm和150mm口径的球面镜进行检测,实现了传统刀口仪不能完成的定量检测,获得了面形分布,检测精度P-V值达到0.12λ(λ=532nm)。通过与干涉仪测得P-V值0.057λ相比较,验证了数字刀口检测的可行性,而且得到的数据还可进一步进行像差分析,为镜面误差的加工修正提供依据。更多还原

【Abstract】 In order to conveniently and quantitatively test the surface shape of large aperture optics, a digital knife-edge tester is integrated with a traditional knife-edge tester, CCD image processing and a computer aid calculation. The knife-edge position corresponding to the threshold is determined by image processing technique and the frequency spectrum is described by introduction of parameter PSD. Test for spherical mirrors with apertures of 125mm and 150mm shows that the integrated tester can implement quantitative test that the traditional knife-edge tester fails to do. The tester obtains the surface shape distributions of optics with a test accuracy up to 0.12λ(λ=532nm). Compared with the P-V value of 0.057λ obtained by an interferometer, the digital knife-edge tester is feasible. The obtained data can be further used for aberration analysis which provides a basis to update surface error during mirror manufacturing.更多还原