Pseudo-Isochromatic Plates for Testing Color Perception

An extraordinary piece of medical and scientific history. This is the American Optical Company's eighteen-plate selection of color blindness test charts, approved by the Inter-Society Color Council Subcommittee on ISCC Problem 11: Color Blindness Studies, and engraved and printed by Beck Engraving Co., Inc., Philadelphia and New York.

The plates correspond to the Hardy, Rand, and Rittler standards from the Institute of Ophthalmology, New York. Housed in its original cloth-covered slipcase, which shows heavy wear with fraying at corners and edges. The spiral-bound test book itself is in good condition with all eighteen plates present and colors vivid.

Exceptionally rare: stamped on the interior with the inventory seal of the New York University Post Graduate Medical School, Dept. of Medicine, dated February 23, 1950, and numbered No. 18. A genuine artifact of mid-century medical practice and visual science.