Ion thermal diffusion theory was applied to analyze the influence on numerical aperture and focal length of planar square aperture microlens array (PMLA). Moreover, numerical aperture and focal length with different ion-exchanging time but the same size of mask aperture were measured experimentally. Then, we measured the longitudinal and transverse spherical aberration by the method of parallel light incidence and emergent light pupil and improved the aberration of square-aperture PMLA by annealing treatment. Experiment results show that the spherical aberration is decreased obviously after annealing process. Meanwhile, imaging resolution is also improved more greatly. PMLA optical system with continuously adjustable focal length was proposed, which was made up of two pieces of square aperture PMLA and an aspherical lens and focal length can be adjusted continuously just by precisely adjusting the distance between the two pieces of square aperture PMLA.

Date Published: 8 September 2011
PDF: 7 pages
Proc. SPIE 8191, International Symposium on Photoelectronic Detection and Imaging 2011: Sensor and Micromachined Optical Device Technologies, 819124 (8 September 2011); doi: 10.1117/12.901031

Published in SPIE Proceedings Vol. 8191:
International Symposium on Photoelectronic Detection and Imaging 2011: Sensor and Micromachined Optical Device Technologies
Yuelin Wang; Huikai Xie; Yufeng Jin, Editor(s)