Surface-cleanliness inspection apparatus for optical component based on machine vision

In high-power laser systems, such as NIF and SG-III, the contamination existing on the optical surfaces will reduce the performance of load and even lead damage to optical components. It is important to acquire the cleanliness level for obtaining ideal functionality. The existing methods are usually low efficiency or low accuracy or high cost in inspection process. A new inspection system based on machine vision has been introduced in this paper. We design three-dimensional control platform and clamp, choosing step motors and grating to implement high-precision control, using linear CCD with pixel 10μm*10μm as the image acquisition, adopting halogen lamp as light source and employing image processing technology to gain the characteristic parameters. Through the calibration experiments, the detection error is within ± 10%. Experiment of optical element with size 400mm*400mm shows that, the apparatus can complete the single face scan and analysis in 16 minutes. It can greatly improve the examine efficiency.