Apparatus and method for testing the motion contrast visual sensitivity of an individual
AssigneeVistech Consultants, Inc.
InventorsArthur P. Ginsburg, David A. Ginsburg, Robert P. Ginsburg
Life of this patent
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Abstract
The motion contrast visual sensitivity of an individual is tested by means of a target having thereon patches each composed of alternating light and dark bars, with individual patches varying in contrast and spatial frequency, and also in orientation. The target is viewed by way of a slot through a housing positioned in front of the individual under test, and a shutter rotating within the housing at a controlled speed periodically blocks the slot at a rate sufficiently slow, e.g. 30 cycles per second, for the observer to detect the resulting conditions of flicker.
Claims12
Apparatus for testing subjectively the visual motion contrast sensitivity of an individual, comprising:
- (a) means for presenting a series of targets at a predetermined location,
- (b) means establishing a viewing position for an individual to be tested having a limited line of sight to said target location,
- (c) each of said targets consisting of light and dark areas with said dark areas on each said target being of the same value but differing in value from said dark areas on other said targets to provide said targets with correspondingly different levels of contrast, and
- (d) means for selectively blocking and unblocking said line of sight at a rate which will cause the human eye to detect flicker, and thereby promoting determination of the levels of contrast in said targets which are detected by the individual at said viewing position under such conditions of flicker.
Apparatus for testing the visual motion contrast sensitivity of an individual, comprising
- (a) a housing having a viewing opening therethrough,
- (b) means projecting from one side of said housing for holding a target having thereon alternating light and dark areas arranged for testing the visual contrast sensitivity of an observer,
- (c) means projecting from the other side of said housing for establishing a viewing position from which an observer can view said target only through said viewing opening, and
- (d) means for imparting to said target an apparent flickering movement with respect to said viewing position.
The method of testing the visual motion contrast sensitivity of an individual which comprises the steps of
- (a) locating an eye of an observer to be tested at a predetermined viewing position relative to a target having thereon multiple alternating light and dark areas which vary in contrast and/or spatial frequency,
- (b) imparting to said target an apparent flickering movement with respect to said viewing position, and
- (c) determining the ability of such eye to detect the differences between said flickering target areas.
Dependencies are inferred from the claim text.