发明授权
US5216458A Apparatus and method for testing visual accuity and contrast sensitivity
失效
用于测试视觉敏感性和对比度敏感度的装置和方法
- 专利标题: Apparatus and method for testing visual accuity and contrast sensitivity
- 专利标题(中): 用于测试视觉敏感性和对比度敏感度的装置和方法
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申请号: US701491申请日: 1991-05-16
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公开(公告)号: US5216458A公开(公告)日: 1993-06-01
- 发明人: Joseph F. Andera , Pete Kaldis , Richard J. Unger
- 申请人: Joseph F. Andera , Pete Kaldis , Richard J. Unger
- 申请人地址: IL Chicago
- 专利权人: Stereo Optical Company, Inc.
- 当前专利权人: Stereo Optical Company, Inc.
- 当前专利权人地址: IL Chicago
- 主分类号: A61B3/02
- IPC分类号: A61B3/02
摘要:
A vision testing apparatus and a method for testing vision in terms of contrast sensitivity and spatial frequency response are provided. The apparatus and method utilize a plurality light-polarizing optotypes which are provided on sheets of an oriented polymeric material. The optotypes are presented one at a time to a patient in conjunction with a polarizing filter such that rotation of the filter relative to the optotype will cause the contrast of the optotype to vary from a first condition wherein the pattern of the optotype is indistinguishable from its background to a second condition wherein the optotype is seen at a maximum level of contrast. The patient will indicate the point at which he or she first sees the optotype. The sequential presentation of a series of optotypes having patterns which vary in their spatial frequencies will provide a measure of both contrast sensitivity and spatial frequency response for each patient tested.
公开/授权文献
- US5762163A Step stool 公开/授权日:1998-06-09
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