Research On Image Quality Measurement Technology Of Ultraviolet Optical System Based On OTF

The quick development of ultraviolet electrical system calls for an accurate image quality evaluation. Using digital Fourier analysis method, the ultraviolet (260nm-400nm) OTF (Optical Transfer Function) measurement technology was researched.Firstly, measurement equipment was set up with the OTF theory. The simulation software was compiled with langue of Labview and the nuclear arithmetic was analyzed. The frequency superposition and barrier effect which are aroused by Fourier transformation were discussed.Secondly, in order to measure the ultraviolet weak signal, the target radiant intensity was amplified, the lamp-house was modulated, the lock-phases magnify technology was used and high sensitive detector was chosen. At last, a simulation with Labview was established, which account for the validity the above means.Thirdly, a group of measurement on focus and defocus were made. Three kinds of different LSF data processing methods were put forward, and their applicable situation was discussed. The FWHM was researched; the shortage of tradition calculation method was analyzed. A new method, which called line interpolation, can improve the measurement accuracy.Finally, the influences of assistant optical system, slot width and detector to measure-ment results were discussed, and the revising method were put forward respectively. The equipment uncertainty measurement of MTF was evaluated, and the results are on-axis 0.03 and off-axis 0.05.