Research On Cavity Ringdown Simultaneous Measurement Technology Of Multi-surface Parameters Of Laser Components

Nowadays,optical components with high reflectivity which's reflectance are higher than 99.9% are actually more and more widely used in fields,such as position guidance field,aerospace exploration field,nuclear field and so on.The surface parameters of high reflectivity laser components have a significant impact on the performance improvement and product quality control of these systems.Therefore,the research on the accurate detection method of multi-parameters on the surface of high-precision optical components has made great progress in the field of optical inspection.At present,the only way to accurately detect ultra-high reflectivity is the cavity ring-down technique,which has the advantages of absolute measurement,no light fluctuation,and extremely low measurement error.The current research has only been developed to simultaneously detect the reflectance and transmittance of the surface of highly reflective optics,and there is no single system that can simultaneously detect the reflectivity,transmittance,and scattering of the surface of a highly reflective laser element.The optical feedback technology based on cavity ring-down is a common method for detecting high-reflective optical components due to its simple device,low cost and high measurement accuracy.Based on the optical feedback cavity ring down technique,this paper studies the technology of simultaneously detecting the reflectivity,transmittance and scattering of the surface of highly reflective laser components,including:(1)Based on the theory of optical surface scattering,the distribution of surface scattering of laser optical components is explored.Compared with the traditional optical surface light scattering measurement method,the optical surface scattering measurement method based on cavity ring-down method is explored.(2)A technique based on cavity ring-down theory for simultaneously imaging or measuring the surface scattering,transmittance and reflectivity of high-reflection laser elements or high-transmission laser elements is proposed.A complete measurement system was built and two high reflectivity samples and two high transmittance samples were tested for two-dimensional scanning imaging and measurement of reflectance,transmittance and surface scattering.(3)Based on the Labview platform,the data automation acquisition system was designed and improved.The three-channel signal single-point data acquisition pro-gram of reflectivity,transmittance and surface scattering was programmed.The three-channel scanning two-dimensional scanning program for reflectivity,transmittance,and surface scattering was improved.(4)A data processing program based on MATLAB was written,and the experimental data was fitted and analyzed.The relationship between the imaged data and the surface defects of optical components was explored.