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USH76H
Expired / Lapsed
US
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Instructional polariscope
Assignee: United States Department of the Army
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Filing: 1983-02-10
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Granted: 1986-07-01
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Expires: 2003-02-10
Abstract
Abstract An instructional polariscope which is easily disassembled, reassembled, cbrated and operated in the classroom by individual students for the purposes of teaching and demonstrating the interoperation of components of a polariscope and the principles of photoelasticity. This polariscope can be assembled for use as either a plane or a circular polariscope and employs a reflector which allows use of an external light source.
Inventors
- 👤 Bruce W. Cotterman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 16:35
CPC Classifications
G; G09; G09B; G09B23/00; G09B23/06
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
280 words
A dismountable instructional polariscope for analyzing stresses in a birefingent specimen, said polariscope being adapted to be dismounted without tools, comprising: a base having a viewing end and a light-source end opposite said viewing end, a load cell fixedly mounted on said base for holding said specimen, means associated with said load cell for creating stresses in said specimen, a polarizer comprising a first annular frame formed with a first peripheral groove and having a first hole at the center of said first annular frame, and a lens of polarizing material attached to said first annular frame for covering said first hole, an analyzer comprising a second annular frame formed with a second peripheral groove and having a second hole at the center of said second annular frame, and a lens of polarizing material attached to said second annular frame for covering said second hole, a first support, fixed to said base intermediate said light-source end and said load cell, and formed with a concave surface to slidably and detachably receive said first peripheral groove of said polarizer for rotation thereon solely by hand, and to support said polarizer thereon solely by gravity, a second support, fixed to said base intermediate said viewing end and said load cell, and formed with a concave surface to slidably and detachably receive said second groove of said analyzer for rotation thereon solely by hand, and to support said analyzer thereon solely by gravity, said base, said load cell, said annular frames, and said supports comprising wood, and a light reflector, detachably disposed solely by gravity adjacent said light-source end of said base, for directing light through said polarizer, said specimen, and said analyzer.
Claim 2
Dependent Claim
280 words
A dismountable instructional polariscope for analyzing stresses in a birefingent specimen, said polariscope being adapted to be dismounted without tools, comprising: a base having a viewing end and a light-source end opposite said viewing end, a load cell fixedly mounted on said base for holding said specimen, means associated with said load cell for creating stresses in said specimen, a polarizer comprising a first annular frame formed with a first peripheral groove and having a first hole at the center of said first annular frame, and a lens of polarizing material attached to said first annular frame for covering said first hole, an analyzer comprising a second annular frame formed with a second peripheral groove and having a second hole at the center of said second annular frame, and a lens of polarizing material attached to said second annular frame for covering said second hole, a first support, fixed to said base intermediate said light-source end and said load cell, and formed with a concave surface to slidably and detachably receive said first peripheral groove of said polarizer for rotation thereon solely by hand, and to support said polarizer thereon solely by gravity, a second support, fixed to said base intermediate said viewing end and said load cell, and formed with a concave surface to slidably and detachably receive said second groove of said analyzer for rotation thereon solely by hand, and to support said analyzer thereon solely by gravity, said base, said load cell, said annular frames, and said supports comprising wood, and a light reflector, detachably disposed solely by gravity adjacent said light-source end of said base, for directing light through said polarizer, said specimen, and said analyzer.
Claim 3
Dependent Claim
227 words
A dismountable instructional polariscope as claimed in claim 1 further comprising: a polarizer quarter-wave plate comprising a third annular frame formed with a third peripheral groove and having a third hole at the center of said third annular frame, and a lens of wave-plate material attached to said third annular frame and covering said third hole, an analyzer quarter-wave plate comprising a fourth annular frame formed with a fourth peripheral groove and having a fourth hole at the center of said fourth annular frame, and a lens of wave-plate material attached to said fourth frame for covering said fourth hole, a third support, fixed to said base intermediate said polarizer and said load cell, and formed with a concave surface to slidably and detachably receive said third peripheral groove of said polarizer quarter-wave plate for rotation thereon solely by hand, and to support said polarizer quarter-wave plate thereon solely by gravity, a fourth support, fixed to said base intermediate said analyzer and said load cell, and formed with a concave surface to slidably and detachably receive said fourth peripheral groove of said analyzer quarter-wave plate for rotation thereon solely by hand, and to support said analyzer quarter-wave plate thereon solely by gravity, and said polarizer quarter-wave plate and said analyzer quarter-wave plate receiving light from said light source when disposed on said third and fourth supports, respectively.
Claim 4
Dependent Claim
33 words
A dismountable instructional polariscope as claimed in claim 1 wherein: said light reflector, when disposed on said base, is disposed to receive light from a source external to, and unsupported by, said polariscope.
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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) | 1989-06-30 | 1989-12-30 | 1990-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-06-30 | 1993-12-30 | 1994-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-06-30 | 1997-12-30 | 1998-07-01 | $7700.00 | Window Closed / Lapsed |