Numerical Analysis of Tightly Focused Spot for Confocal Microscopy Illumination by a Real Lens System
Portland, 8 August, 2019, M&M 2019 – Microscopy and Microanalysis
Confocal microscopy is widely used in both materials science and life sciences. It has good imaging performance due to the filtering of background noise. The illumination by a high numerical aperture condenser is essential for good image quality. It is studied quite intensively using the Debye-Wolf integral, which often assumes an aplanatic lens system . However, the aberration of the misaligned system often affects the quality of the focal spot in experiments. In this work, we perform the physical-optics modeling of the real condenser lens system with inclusion of full vectorial effects. The schematic of the illumination part of the confocal microscopy is shown in Fig. 1 (a). The Gaussian wave source is generated in a fiber with a relative low divergence. It is collimated by a collimating lens (Edmund Optics: 49664) and then focused by a high numerical aperture condenser lens (Patent: US04384765; NA=0.95) to illuminate the sample.