Structured Laser Illumination Planar Imaging method for Filtering Stray Light applied to Temperature Sensitive Paints measurement

摘要

Stray light is the main noise source for planar imaging measurement technique, which can affect the accuracy ofresults directly. A method of Structured Laser Illumination Planar Imaging (SLIPI) was used to solve this issue. The keyof SLIPI is periodic modulation of laser spatial intensity and implementation of post filtering algorithm. In this paper,cylindrical micro lens array was used to modulate the spatial intensity of laser periodically, which was compared withRonchi ruling. The post filtering algorithm adopts phase-locked detection method. The signal results can be separatedfrom the noisy image using only one measurement image by this method. SLIPI method has been used in TemperatureSensitive Paints measurement experiments. A diagnostic optical path combining cylindrical micro lens array andcylindrical mirror was designed for the need of surface light source irradiation. The results show that the method ofSLIPI can be applied to most planar imaging measurement techniques, and the accuracy of two-dimensional parametermeasurement can be further improved.