Some optical principles of the clinical specular microscope.

The clinical specular microscope is used to examine and photograph human endothelial cells in vivo. An optical analysis is presented here in simple form to aid the ophthalmologist or visual scientist in understanding how this instrument can be used in a quantitative manner to measure the size of the magnified endothelial cells and the thickness of the overlying cornea. An error analysis is discussed in order to demonstrate some aspects of the precision of the determination.