US3675004A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photoflash lamp and multiple flashlamp system
Assignee: Philips North America LLC
•
Filing: 1970-06-15
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Granted: 1972-07-04
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Expires: 1990-06-15
Abstract
Abstract An improved combustible photoflash lamp is described which produces an increased peak and integrated lumen output per unit lamp volume, and an improved color temperature of light output. The combustible comprises shredded foil substantially comprised of hafnium metal which is burned in a super pressure oxygen atmosphere. The shredded foil cross-sectional area can be varied to further vary the color temperature of the light output. The lamp envelope including the protective lacquer coating on the exterior thereof is substantially transmissive of all visible radiations generated upon operation of the lamp. This lamp eliminates the need for a light-absorbing, color-correcting blue lacquer coating in order to achieve a high color temperature of light output. The lamp is conveniently utilized in an improved multiple flashlamp system.
Inventors
- 👤 Earl A Gulbrasen
- 👤 Richard L Tallman
- 👤 Kenneth F Andrew
- 👤 Bruce T Buzalski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 08:00
CPC Classifications
F; F21; F21K; F21K5/00; F21K5/02
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
64 words
The lamp as specified in claim 1 wherein; said combustible foil consists essentially of hafnium that contains about three percent by weight of zirconium, and the color temperature of the light output is varied from about 4,600* to 5,000* K by varying the cross-sectional area of said shredded foil from approximately 1.2 X 10 6 square inch to 1.9 X 10 6 square inch.
Claim 2
Dependent Claim
64 words
The lamp as specified in claim 1 wherein; said envelope has a volume less than one cubic centimeter, said combustible shredded foil is present in an amount of about 4 X 10 4 gram-atom per cubic centimeter of lamp volume, and said oxygen atmosphere is about 8 atmospheres pressure, with the peak lumen output being about 0.6 megalumens per cubic centimeter of lamp volume.
Claim 3
Dependent Claim
20 words
The lamp as specified in claim 1 wherein said combustible shredded foil contains up to about 10 weight percent zirconium.
Claim 4
Dependent Claim
97 words
In a multiple-flashlamp system comprising a plurality of flashlamps, an integral reflector about each lamp, and a plastic enclosure structure about said lamps, the improvement comprising a hermetically sealed envelope which is substantially transmissive of visible radiations, ignition means to initiate combustion, a predetermined oxygen atmosphere, and combustible shredded foil substantially comprising hafnium, with said plastic enclosure structure being substantially transmissive of visible radiations, and the light output from said system upon flashing of an individual lamp having a color temperature, at the time of peak lumen output, which is at least greater than about 4,600* K.
Claim 5
Dependent Claim
82 words
The improvement set forth in claim 5 wherein; said envelope has a volume of about 0.6 cubic centimeter, said combustible shredded foil is present in an amount of about 4 X 10 4 gram-atom per cubic centimeter of lamp volume, and said oxygen atmosphere is about eight atmospheres, to produce light output with an average value of about 650 zonal lumen seconds in 25 milliseconds, with a peak lumen output of about 0.1 peak zonal megalumens per cubic centimeter of lamp volume.
Claim 6
Dependent Claim
83 words
In a photoflash lamp, the combination of; a sealed glass envelope that has a protective coating of clear plastic thereon and contains oxygen at super-atmospheric pressure, a combustible material within said envelope consisting essentially of reactor grade hafnium foil in shredded form, and means for igniting said shredded hafnium foil, the thickness and width of the hafnium foil shreds being so correlated that the lamp, when ignited, produces a flash of light that has a color temperature of at least about 4,600* K.
Claim 7
Dependent Claim
48 words
The combination of claim 7 wherein; said envelope Has a volume less than 5 cubic centimeters and contains several atmospheres of oxygen, and the cross-sectional area of the hafnium foil shreds is within a range of approximately 1.2 X 10 6 to 1.9 X 10 6 square inch.
Claim 8
Dependent Claim
41 words
The combination of claim 8 wherein; said envelope has a volume of about 0.6 cubic centimeter and contains about 8 atmospheres of oxygen, and the hafnium foil shreds are about 0.0009 inch thick and from about 0.0013 to 0.0021 inch wide.
Claim 9
Dependent Claim
34 words
The combination of claim 9 wherein; said envelope contains about 44 milligrams of shredded hafnium foil, and the hafnium foil shreds have a thickness of about 0.0009 inch and a width of about 0.0013.
Claim 10
Dependent Claim
35 words
The combination of claim 9 wherein; said envelope contains about 44 milligrams of shredded hafnium foil, and the hafnium foil shreds have a thickness of about 0.0009 inch and a width of about 0.0021 inch.
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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) | 1975-07-04 | 1976-01-03 | 1976-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-04 | 1980-01-03 | 1980-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-04 | 1984-01-03 | 1984-07-04 | $7700.00 | Window Closed / Lapsed |