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US4677008A Expired / Lapsed US ⏱️ 0.0 years remaining

Safe and efficient self-luminous microspheres

Assignee: Individual
•
Filing: 1985-08-19
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Granted: 1987-06-30
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Expires: 2005-08-19
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Abstract

Abstract This invention relates to a means for more efficiently and more safely providing self-luminous lighting devices for use in signs, markers, indicators and the like. Said invention provides self luminosity by means of a plurality of glass microspheres containing both a light emitting phosphor and a radioactive gas. The "soft" emission of electrons from the beta emitting gas can not penetrate the glass wall of the microspheres, thereby constituting no radiation hazard. The containment of the self-luminous system within an envelope which does not pass any radiation prevents the deterioration of nearby organic materials. A further advantage of said invention is that the plurality of individual containment envelopes minimize the escape of radioactive gas in the event of any physical damage to an assembly of such envelopes. A still further advantage of my invention is that the radioactive gas completely surrounds the phosphor particles, thus causing light emission from 100 percent of the surface of said particles.

Inventors

  • 👤 Robert D. Webb

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 17:41
CPC Classifications
G; G08; G08B; G08B5/00; C; C09; C09K; C09K11/00; C09K11/04; G09; G09F; G09F13/00; G09F13/42; H; H01; H01J; H01J65/00; H01J65/08; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/131; Y10T428/25; Y10T428/252; Y10T428/29; Y10T428/2982

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 55 words
A self-luminous microsphere comprising: (a) a gas tight envelope; (b) a radio-active gas confined within the envelope; and (c) at least one phosphor particle disposed within the envelope and responsive to the radiation from said gas to become luminous, characterized by said particle being loose within the envelope to thereby receive radiation on all sides.
Claim 2
Dependent Claim 55 words
A self-luminous microsphere comprising: (a) a gas tight envelope; (b) a radio-active gas confined within the envelope; and (c) at least one phosphor particle disposed within the envelope and responsive to the radiation from said gas to become luminous, characterized by said particle being loose within the envelope to thereby receive radiation on all sides.
Claim 3
Dependent Claim 14 words
A self-luminous microsphere as set forth in claim 1 wherein the gas is tritium.
Claim 4
Dependent Claim 20 words
A self-luminous microsphere as set forth in claim 1, wherein the gas is at a pressure greater than atmospheric pressure.
Claim 5
Dependent Claim 20 words
A plurality of microspheres as set forth in claim 1 disposed on a flat surface to act as a sign.
Claim 6
Dependent Claim 20 words
A plurality of microspheres as set forth in claim 1 disposed in a transparent binder to form a luminous paint.
Claim 7
Dependent Claim 46 words
A self-luminous microsphere comprising: (a) a gas tight envelope; (b) a radio-active gas confined within the envelope; and (c) at least one phosphor particle disposed within the envelope and free to move within the envelope, and responsive to radiation from said radio-active gas to become luminous.
Claim 8
Dependent Claim 46 words
A self-luminous microsphere comprising: (a) a gas tight envelope; (b) a radio-active gas confined within the envelope; and (c) at least one phosphor particle disposed within the envelope and free to move within the envelope, and responsive to radiation from said radio-active gas to become luminous.

References Cited (Backward Citations)

US4020203A Cited
US4383382A Cited
US4452861A Cited
US4491620A Cited
US4574102A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-06-29 1990-12-29 1991-06-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-06-29 1994-12-29 1995-06-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-06-29 1998-12-29 1999-06-30 $7700.00 Window Closed / Lapsed

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