The effects of defocus and primary spherical aberration on the images of a straight edge in a confocal microscope are investigated. When the aberrations are small, the sharpness of the edge image may be enhanced. But the images are degraded if the aberrations become strong in the system. In the latter case, one can improve the quality of the edge images, particularly the sharpness, by slightly reducing the aperture size of the objective and the collection lenses. This result is qualitatively verified by experimental results.
© 1994 Optical Society of America
Original Manuscript: March 1, 1993
Revised Manuscript: July 2, 1993
Published: February 1, 1994
Min Gu and Colin J. R. Sheppard, "Effects of defocus and primary spherical aberration on images of a straight edge in confocal microscopy," Appl. Opt. 33, 625-630 (1994)