发明名称 |
Optical magnifier |
摘要 |
An optical magnifier, preferably having only two elements and including a rear negative surface associated with an object to be viewed, which is aspheric. The aspheric surface follows a formula having a sag which is positive to help effect correction for field curvature, astigmatism and distortion. Preferably the lens has at least one other aspheric surface and a diffractive surface. The diffractive surface is preferably on a curved surface to assist in improving the quality of the magnifier with a limited number of elements.
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申请公布号 |
US5703721(A) |
申请公布日期 |
1997.12.30 |
申请号 |
US19950562666 |
申请日期 |
1995.11.27 |
申请人 |
EASTMAN KODAK COMPANY |
发明人 |
BIETRY, JOSEPH R.;ESTELLE, LEE R.;LUDINGTON, PAUL D. |
分类号 |
G02B3/02;G02B25/00;G02B27/00;(IPC1-7):G02B25/00;G02B13/18;G02B27/42 |
主分类号 |
G02B3/02 |
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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