As the development of high powered laser system, the measuring accuracy of optic’s transmissivity need to be improved in order to guarantee all the optics’ quality. This paper analyses all the factors which largely influence the testing accuracy of optics transmissivity when using the spectralphotometer. Experiments are carried out to verify all the deduced results. The results show that the accuracy of wavelength, error of incident angle and divergence of measuring beam would influence the testing result of transmissivity, and the divergence of measuring beam would contrubite to the largest error. Therefore, the testing accuracy could be greatly increased by decreasing the divergence angle of measuring beam.
Three-flat test can separate the reference surface error from the test part surface in the surface measurement by interferometry. The solution based on mirror symmetry of three-flat test is compact and highly accurate. In practice, the error will be introduced when the position of three flats are misalignment or the relative rotation angle are not accurate. The influence of rotation angle error are simulated and discussed. Then the experiment was carried out on three reference flats and the flat surface profiles were derived by mirror symmetry method. The experiment results show good agreement and the difference is in a nanometer level.
We experimentally demonstrated that the microsphere on the top surface of the sample can enhance the imaging
capability of microscope, and possible to arrive a resolution below the conventional diffractive limit. The principle of the
super-resolution was discussed, and mainly due to the transformation of surface wave to propagation wave. The
mechanism of super-resolution and the corresponding phenomenon are presented in the paper.