发明名称 |
Method and apparatus for objective determination of visual contrast sensitivity functions |
摘要 |
A method and apparatus for objectively determining the visual contrast sensitivity function of a human subject involves subjecting the vision of the human subject to a plurality of sine wave gratings differing in spatial frequency and contrast levels. As the subject views the grating patterns on a video monitor, the brain wave activity of the subject is detected and steady state Fourier spectra of the activity are recorded. In each spectrum corresponding to a grating pattern of a particular spatial frequency, a visual evoked potential component may be distinguished from noise by adjusting the contrast level of the grating pattern. A contrast threshold used in deriving the visual contrast sensitivity function is identified for each grating pattern of a particular spatial frequency by pinpointing the contrast level at which the visual evoked potential component becomes indistinguishable from noise in the spectrum.
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申请公布号 |
US4493539(A) |
申请公布日期 |
1985.01.15 |
申请号 |
US19820394040 |
申请日期 |
1982.06.30 |
申请人 |
THE UNITED STATES OF AMERICA AS REPRESENTED BY THE SECRETARY OF THE AIR FORCE |
发明人 |
CANNON, JR., MARK W. |
分类号 |
A61B3/06;A61B3/09;A61B5/0484;(IPC1-7):A61B3/10;A61B3/02 |
主分类号 |
A61B3/06 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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