PROBLEMS IN THE PHYSIOLOGY OF VISUAL ACUITY

CONTENTS

The Light Sense

1. The Minimum Visible

2. Influence of Aberrations on the Minimum Visible

3. Influence of Sensory Adaptation on the Minimum Visible

4. Gradations of the Light Sense, with Changes in Intensity

The Color Sense

The Form Sense

1. The Minimum Separable

2. Measurements of the Minimum Separable

3. The Alining Power of the Eye

4. Differences Between the Minimum Separable and the Alining Power of the Eye

Visual Acuity as Measured by the Snellen Charts

Summary

In the routine examination of patients the ability of the eye to see is tested with the well known Snellen letter charts, and the results of this test are recorded as the patient's visual acuity. It is generally understood that these charts test the optical perfection of the refracting systems of the eye, the functional capacity of the retina, at least of its foveal portion, and the conducting power of the macular fibers of the optic nerve and