Although visual acuity is of chief concern to the optometrist from the professional standpoint, the physicist should be no less concerned from the standpoint of its applications to work in optics and illumination. Visual acuity is indeed difficult to measure and many types of acuity tests have been devised. The Clason acuity meter and the Snellen chart are the accepted standards used by optometrists. Another test for measuring acuity, which is administered on the stereoscope, is one of many visual tests that has been developed by Betts, Director of Teacher Education, State Normal School, Oswego, N. Y., who worked jointly with the Keystone View Company of Meadville, Penna.
Proceedings of the Iowa Academy of Science
©1938 Iowa Academy of Science, Inc.
Schepler, H. C.
"Psycho-Physical Analysis of the Betts Visual Acuity Test,"
Proceedings of the Iowa Academy of Science, 45(1), 191-194.
Available at: https://scholarworks.uni.edu/pias/vol45/iss1/43