dark focus

Quick Reference

A stable resting accommodation (1) of the eye's crystalline lens, usually corresponding to a focal distance of about one metre, that the eye assumes when confronted with a stimulus lacking any features on which to focus, such as a completely enveloping blank screen resembling the inside of a giant ping-pong ball, or a blank screen viewed through a lens that makes it appear too close to focus on, or an isoluminant stimulus, or complete darkness. It produces a temporary condition of anomalous myopia.

Subjects: Psychology.

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