发明授权
- 专利标题: Apparatus for eye examination
- 专利标题(中): 眼睛检查装置
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申请号: US736072申请日: 1985-05-20
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公开(公告)号: US4679921A公开(公告)日: 1987-07-14
- 发明人: Kenji Yamada
- 申请人: Kenji Yamada
- 申请人地址: JPX Tokyo
- 专利权人: Nippon Kogaku K. K.
- 当前专利权人: Nippon Kogaku K. K.
- 当前专利权人地址: JPX Tokyo
- 优先权: JPX59-107308 19840526
- 主分类号: A61B3/02
- IPC分类号: A61B3/02 ; A61B3/103 ; A61B3/10
摘要:
An eye-examining apparatus comprises a first positive lens unit, a negative lens unit, a second positive lens unit, a third positive lens unit and a target mark arranged in the named order from the side of the examined eye. The third positive lens unit is mounted movably along the optical axis. Between the first and second positive lens units there is interposed on astigmatic system rotatable about the optical axis. The negative lens unit, the second positive lens unit and the third positive lens unit are so arranged as to form an image of the mark at a position near the focal point on the target mark side of the first lens unit. The focal point on the examined eye of the composite system composed of the negative lens unit, the second positive lens unit and the third positive lens unit is approximately coincident with the position conjugate with the pupil of the examined eye relative to the first positive lens unit. The diopter of the apparatus is changed by moving the third positive lens unit and the change of the axis and degree of astigmatism are achieved by rotating the astigmatism system.
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