Patent US5177637A successfully refreshed from Google Patents.
US5177637A
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Focusing screen including different height microlenses arranged in a cyclical pattern
Assignee: Nikon Corp
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Filing: 1991-09-06
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Granted: 1993-01-05
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Expires: 2011-09-06
Abstract
Abstract In a focusing screen having a large number of microlenses regularly arranged thereon, heights of microlenses are n different values. The microlenses having the same height are cyclically arranged. In another aspect, the heights of the microlenses in a similar focusing screen are randomly distributed over ranges centered on n central values, and the microlenses having the same central value are cyclically arranged. In still another aspect, in a method of manufacturing a focusing screen having micropatterned projections by a so-called proximity exposure method, dimensions of the micropatterns of the mask vary centered on the n different values, and the micropatterns having the same central values are cyclically arranged.
Inventors
- 👤 Shinichi Tsukada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:37
CPC Classifications
G; G03; G03B; G03B13/00; G03B13/18; G03B13/24; G03B2217/00; G03B2217/005
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
63 words
In a focusing screen having a large number of microlenses regularly distributed in an array, the improvement wherein said microlenses are substantially uniformly cross-dimensioned and arranged as a plurality of intermingled groups, with the microlenses of each group having a predetermined height different from that of the microlenses of each other group and occupying a respective cyclical pattern of positions within said array.
Claim 2
Dependent Claim
63 words
In a focusing screen having a large number of microlenses regularly distributed in an array, the improvement wherein said microlenses are substantially uniformly cross-dimensioned and arranged as a plurality of intermingled groups, with the microlenses of each group having a predetermined height different from that of the microlenses of each other group and occupying a respective cyclical pattern of positions within said array.
Claim 3
Dependent Claim
75 words
In a focusing screen having a large number of microlenses regularly distributed in an array, the improvement wherein said microlenses are arranged as a plurality of intermingled groups, with the microlenses of each group having heights which are randomly distributed within a predetermined range about a predetermined central height value, the central height value being different for each group, and the microlenses of each group occupying a respective cyclical pattern of positions within said array.
Claim 4
Dependent Claim
75 words
In a focusing screen having a large number of microlenses regularly distributed in an array, the improvement wherein said microlenses are arranged as a plurality of intermingled groups, with the microlenses of each group having heights which are randomly distributed within a predetermined range about a predetermined central height value, the central height value being different for each group, and the microlenses of each group occupying a respective cyclical pattern of positions within said array.
Claim 5
Dependent Claim
17 words
A focusing screen according to claim 2, wherein the microlenses of said array are substantially uniformly cross-dimensioned.
Claim 6
Dependent Claim
21 words
A focusing screen according to claim 2, wherein a width of said predetermined range is the same for each said group.
Claim 7
Dependent Claim
17 words
A focusing screen according to claim 4, wherein the microlenses of said array are substantially uniformly cross-dimensioned.
Claim 8
Dependent Claim
45 words
A focusing screen according to claim 2, wherein for each said group, a width R of said predetermined range is defined as follows: 0<R<1.5Q/(n-1) where Q is the difference between the maximum and minimum central height values and n is the number of said groups.
Claim 9
Dependent Claim
21 words
A focusing screen according to claim 6, wherein the width of said predetermined range is the same for each said group.
Claim 10
Dependent Claim
17 words
A focusing screen according to claim 7, wherein the microlenses of said array are substantially uniformly cross-dimensioned.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-01-05 | 1996-07-06 | 1997-01-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-01-05 | 2000-07-06 | 2001-01-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-01-05 | 2004-07-06 | 2005-01-05 | $7700.00 | Window Closed / Lapsed |