Motion and vision. I. Stabilized images of stationary gratings.

To demonstrate that eye movements have profound effects on the sine-wave contrast threshold, the author uses a new method of stabilizing the retinal image, in which the Purkinje reflections from the eye move the stimulus pattern displayed on a CRT screen. Calibration of this compensatory motion is very critical; a gain error greater than 1% may produce significant destablization. Under optimum conditions, image stabilization elevates the subject's contrast threshold by a factor of about 20; it also produces after-images with resolution greater than 12 c/deg. These results compare favorably with those obtained by other methods.