US4659112A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Identification system comprising a partially reflective retardation device
Assignee: Optical Devices Inc
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Filing: 1984-12-03
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Granted: 1987-04-21
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Expires: 2004-12-03
Abstract
Abstract There is disclosed a tamper-free identification system, such as an ID card, comprising an information-bearing substrate made of a flexible but substantially rigid material, a partial light reflector superposed over said substrate which produces a substantially nondepolarizing light reflection, and a substantially transparent 90° retarder superposed over said reflector. Said identification card can be manufactured at low cost using techniques known in the art, and with the aid of a simple and inexpensive analyzer such as a linear light polarizer, fraudulent alternations of the identification card can readily be detected.
Inventors
- 👤 Daniel T. Reiner
- 👤 Lawrence Bolt
- 👤 Philip W. Morlan, Jr.
- 👤 Ali Tavasolian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:04
CPC Classifications
B; B42; B42D; B42D25/00; B42D25/20; B42D25/22; G; G06; G06K; G06K19/00; G06K19/06; G06K19/08; G06K19/10; G06K19/14; B42D25/30; B42D25/36; B42D25/373; B42D25/40; B42D25/405; B42D25/425; B42D2033/04; B42D2033/10; B42D2033/18; B42D2033/20; B42D2033/30; B42D2033/32; B42D2035/02; B42D2035/06; B42D2035/20; B42D25/324; B42D25/378; B42D25/391; B42D25/45; B42D25/465; B42D25/47; Y; Y10; Y10S; Y10S283/00; Y10S283/904
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
47 words
A tamper-free identification system comprising an information-bearing substrate made of a flexible but substantially rigid material, a partially transparent partial light reflector superposed over said substrate and a substantially transparent 90° retarder superposed over said reflector, said reflector being adapted to produce a substantially nondepolarizing light reflection.
Claim 2
Dependent Claim
47 words
A tamper-free identification system comprising an information-bearing substrate made of a flexible but substantially rigid material, a partially transparent partial light reflector superposed over said substrate and a substantially transparent 90° retarder superposed over said reflector, said reflector being adapted to produce a substantially nondepolarizing light reflection.
Claim 3
Dependent Claim
21 words
The identification card as defined in claim 1, wherein said reflector comprises a plastic layer having a metal layer deposited thereon.
Claim 4
Dependent Claim
16 words
The identification card as defined in claim 2, wherein said plastic layer consists essentially of poly(ethyleneterephthalate).
Claim 5
Dependent Claim
17 words
The identification card as defined in claim 2, wherein said plastic layer consists essentially of poly(vinyl chloride).
Claim 6
Dependent Claim
21 words
The identification card as defined in claim 1, wherein said retarder comprises an oriented plastic material stained with a dichroic material.
Claim 7
Dependent Claim
18 words
The identification card as defined in claim 5, wherein said oriented plastic material consists essentially of poly(vinyl alcohol).
Claim 8
Dependent Claim
18 words
The identification card as defined in claim 6, wherein the dichroic material consists essentially of a dichroic dye.
Claim 9
Dependent Claim
58 words
The identification card as defined in claim 1, wherein said retarder carries a mark which is substantially invisible when the identification card is viewed without the aid of an analyzer but is clearly visible when the identification card is viewed through an analyzer, said mark having been prepared by substantially destroying the 90° light-retardation effect of said retarder.
Claim 10
Dependent Claim
21 words
The identification card as defined in claim 8, wherein said retarder comprises an oriented plastic material stained with a dichroic material.
Claim 11
Dependent Claim
18 words
The identification card as defined in claim 10, wherein said oriented plastic material consists essentially of poly(vinyl alcohol).
Claim 12
Dependent Claim
18 words
The identification card as defined in claim 10, wherein the dichroic material consists essentially of a dichroic dye.
Claim 13
Dependent Claim
20 words
The identification card as defined in claim 8, which further comprises a portective layer superposed over the 90° retarder layer.
Claim 14
Dependent Claim
24 words
The identification card as defined in claim 8, wherein a light retardation of substantially 90° is produced at an operative wavelength of 540 nm.
Claim 15
Dependent Claim
21 words
The identification card as defined in claim 8, wherein said reflector comprises a plastic layer having a metal layer deposited thereon.
Claim 16
Dependent Claim
16 words
The identification card as defined in claim 14, wherein said plastic layer consists essentially of poly(ethyleneterephthalate).
Claim 17
Dependent Claim
17 words
The indentification card as defined in claim 14, wherein said plastic layer consists essentially of poly(vinyl chloride).
Claim 18
Dependent Claim
20 words
The identification card as defined in claim 1, which further comprises a protective layer superposed over the 90° retarder layer.
Claim 19
Dependent Claim
24 words
The identification card as defined in claim 1, wherein a light retardation of substantially 90° is produced at an operative wavelength of 540 nm.
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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) | 1990-04-20 | 1990-10-20 | 1991-04-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-20 | 1994-10-20 | 1995-04-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-20 | 1998-10-20 | 1999-04-21 | $7700.00 | Window Closed / Lapsed |