MEASURE OF VISUAL ACUITY BY MEANS OF EYE MOVEMENTS

Subjective and objective tests of visual acuity were given using the same target, with the same luminance and at the same distance. Objective measurements were obtained by a method based on evoking and arresting a pendular eye movement in response to a grating moved sinusoidally to and fro. Eye movements were recorded by a very precise electronic apparatus including the CAT Computer. Objective and subjective measurements of acuity were found to be highly correlated. The absolute value of acuity was always higher when measured subjectively than when the objective measures were used. The correlation between the objective and subjective measurements are in good agreement with other investigations which differ greatly in method.