Optical projection microlithography for fabricating fine line and optical data storage technique ave extended into submicron region. But many new technical problems will be appeared in transferring such exacting structure by optical method. One of the important subjects is the investigation of the light energy distribution on focal plane. this paper described the experimental results using an automatic focusing system which was produced by Tsinghua Univ. within +0.1u accurasy. Those have been colipared with the calculating results of perfect lens and residual aberration system,and the relation of them was also discussed.
"Study Of Image Structure In The Focal Plane In Microphotolithography System.", Proc. SPIE 0538, Optical Microlithography IV, (23 July 1985); doi: 10.1117/12.947769; https://doi.org/10.1117/12.947769