A method for evaluating microscope objectives to optimize performance of confocal systems

Abstract
SUMMARY: A method for evaluating the performance of microscope objectives on two types of confocal scanning optical microscope is presented. Of these two confocal microscope types, off‐axis beam‐scanning systems are found to require microscope objectives which have been corrected for flatness of field as well as for spherical aberration and astigmatism in order to obtain maximum axial and laterial resolution. In the case of on‐axis specimen‐scanning microscopes, less highly corrected objective lenses (not corrected for flatness of field) may in practice prove to have superior resolving properties.