Patent US4308459A successfully refreshed from Google Patents.
US4308459A
Expired / Lapsed
US
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Ultraviolet radiation detection device
Assignee: Xytronyx Inc
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Filing: 1980-05-22
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Granted: 1981-12-29
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Expires: 2000-05-22
Abstract
Abstract An ultraviolet dosimeter, which indicates dose accumulation by the multicolored change of a sensitized element. The indicated doses are readily observed in bright sunlight by direct comparison with standards.
Inventors
- 👤 Gwyn P. Williams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:38
CPC Classifications
G; G01; G01J; G01J1/00; G01J1/48; G01J1/50; G01T; G01T1/00; G01T1/02; G01T1/06
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
87 words
An ultraviolet dosimeter comprising: (a) an element coated with an ultraviolet sensitive film which changes through a plurality of colors, the color being produced is dependant on the duration of the exposure to ultraviolet radiation in the wavelength range (290-400 nm) which is known to cause enythema and melanogenesis, and (b) a set of comparison colors adjacent to the sensitized element to place the sensitized element in a position where it may be readily compared with the comparison colors to measure the dose of ultraviolet radiation accurately.
Claim 2
Dependent Claim
87 words
An ultraviolet dosimeter comprising: (a) an element coated with an ultraviolet sensitive film which changes through a plurality of colors, the color being produced is dependant on the duration of the exposure to ultraviolet radiation in the wavelength range (290-400 nm) which is known to cause enythema and melanogenesis, and (b) a set of comparison colors adjacent to the sensitized element to place the sensitized element in a position where it may be readily compared with the comparison colors to measure the dose of ultraviolet radiation accurately.
Claim 3
Dependent Claim
33 words
A device as claimed in claim 1, further comprising a plurality of sensitized element, a protective cover and means for advancing unexposed element to position of exposure for successive use of the device.
Claim 4
Dependent Claim
22 words
A device as claimed in claim 1, in which the spectral response of the sensitized element closely matches that of human skin.
Claim 5
Dependent Claim
66 words
A device as claimed in claim 1, in which the sensitized element comprises a plurality of acid sensitive dyes in contact with a halogen containing material in aqueous emulsion said halogen is released and combined with hydrogen from the water contained in the emulsion to make the film acidic upon receiving ultraviolet radiation said dyes changing through multiple colors in response to the degree of acidity.
Claim 6
Dependent Claim
36 words
A device as claimed in claim 1, in which the sensitized element is capable (without a filter) of responding to a dynamic range of from 0.1 to 10,000 millijoules per square centimeter at a 3000 A.
Claim 7
Dependent Claim
23 words
A device as claimed in claim 1, in which the sensitized element is exposed through an aperture which forms part of the device.
Claim 8
Dependent Claim
29 words
A device as claimed in claim 1, in which the sensitized element is exposed through a filter to compensate for differences between artificial and natural forms of ultraviolet radiation.
Claim 9
Dependent Claim
36 words
A device as claimed in claim 4, in which methylene blue and dimethyl yellow dyes are mixed to produce an initially green film which progresses through brown, purple and red upon continued exposure to ultraviolet radiation.
Claim 10
Dependent Claim
28 words
A device as claimed in claim 1, in which the sensitized element is surrounded by the standard comparison color to provide for accurate dose measurement in strong sunlight.
Claim 11
Dependent Claim
75 words
A process for fabricating an ultraviolet dosimeter comprising the steps of: (a) providing a paper substrate, (b) printing sensitized portions on said paper by application of a latex emulsion containing multiple acid sensitive dyes to produce variable colors upon continuing exposure to ultraviolet radiation, and (c) printing on said substrate about said sensitized portions comparison colors corresponding to the colors produced during continued exposure of the sensitized portions to indicate the dose of radiation received.
Claim 12
Dependent Claim
75 words
A process for fabricating an ultraviolet dosimeter comprising the steps of: (a) providing a paper substrate, (b) printing sensitized portions on said paper by application of a latex emulsion containing multiple acid sensitive dyes to produce variable colors upon continuing exposure to ultraviolet radiation, and (c) printing on said substrate about said sensitized portions comparison colors corresponding to the colors produced during continued exposure of the sensitized portions to indicate the dose of radiation received.
References Cited (Backward Citations)
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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) | 1984-12-28 | 1985-06-29 | 1985-12-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-12-28 | 1989-06-29 | 1989-12-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-12-28 | 1993-06-29 | 1993-12-29 | $7700.00 | Window Closed / Lapsed |