• A photographic technique improved the quality of anterior segment photography by using one polarizer in the illumination path and another polarizer that was perpendicularly oriented to the first in front of the camera film back. A significant improvement was noted by impartial masked observers who assessed standard photographs of the iris, conjunctiva, and sclera. A crosslike artifact, observed in photographs using cross-polarizers, was present and originated from corneal birefringence. The significance of the artifact and its possible diagnostic applications were determined.
Fariza E, O'Day T, Jalkh AE, Medina A. Use of Cross-Polarized Light in Anterior Segment Photography. Arch Ophthalmol. 1989;107(4):608–610. doi:10.1001/archopht.1989.01070010622044