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US4705986A Expired / Lapsed US ⏱️ 0.0 years remaining

High color rendering fluorescent lamp

Assignee: Panasonic Holdings Corp
•
Filing: 1987-01-22
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Granted: 1987-11-10
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Expires: 2007-01-22
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Abstract

Abstract A high color rendering fluorescent lamp having two-layered phosphor coating, wherein a first layer is formed immediately on the inner face of glass tube containing phosphors of alkaline earth halophosphate activated by antimony manganese or of alkaline earth holophosphate activated by antimony or both, and a second layer (an overriding layer) is formed on the first layer containing a phosphor having peak wavelength of emission at 470 nm-500 nm and absorbing line spectrum of mercury in visible short wavelength range, at least one of a phosphor of (Sr, Mg) 3 (PO 4 ) 2 :Sn and a phosphor of (Sr, Ba) 3 (PO 4 ) 2 :Sn.

Inventors

  • 👤 Katsuaki Iwama
  • 👤 Mutsuo Takahashi
  • 👤 Haruo Shibata

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 03:45
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/74; C09K11/75; C09K11/76; C09K11/70; C09K11/71; C09K11/77; C09K11/7728; C09K11/7734; C09K11/774; H; H01; H01J; H01J61/00; H01J61/02; H01J61/38; H01J61/42; H01J61/48

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 176 words
A high color rendering fluorescent lamp having: a transparent enclosure containing means for generating ultraviolet light, a first phosphor layer which is provided on the inner face of said transparent enclosure and contains at least one of a phosphor of an alkaline earth metal halophosphate activated by antimony-manganese and a phosphor of alkaline earth metal halophosphate activated by antimony, and a second phoshor layer which is provided further on said first phosphor layer and contains at least a phosphor of strontium-aluminate activated by divalent europium indicated by the general formula Sr 4-x Eu x Al 14 O 25 , wherein 0.02≦x≦0.80, having a peak wavelength of emission at 470 nm-500 nm and absorbing the bright line spectrum of mercury in the visible short wavelength range, and at least one member selected from the group consisting of a phosphor of strontium-magnesium phosphate activated by tin having the formula (Sr, Mg) 3 (PO 4 ) 2 :Sn and a phosphor of strontium-barium-magnesium phosphate activated by tin having the formula (Sr, Ba, Mg) 3 (PO 4 ) 2 :Sn.
Claim 2
Dependent Claim 176 words
A high color rendering fluorescent lamp having: a transparent enclosure containing means for generating ultraviolet light, a first phosphor layer which is provided on the inner face of said transparent enclosure and contains at least one of a phosphor of an alkaline earth metal halophosphate activated by antimony-manganese and a phosphor of alkaline earth metal halophosphate activated by antimony, and a second phoshor layer which is provided further on said first phosphor layer and contains at least a phosphor of strontium-aluminate activated by divalent europium indicated by the general formula Sr 4-x Eu x Al 14 O 25 , wherein 0.02≦x≦0.80, having a peak wavelength of emission at 470 nm-500 nm and absorbing the bright line spectrum of mercury in the visible short wavelength range, and at least one member selected from the group consisting of a phosphor of strontium-magnesium phosphate activated by tin having the formula (Sr, Mg) 3 (PO 4 ) 2 :Sn and a phosphor of strontium-barium-magnesium phosphate activated by tin having the formula (Sr, Ba, Mg) 3 (PO 4 ) 2 :Sn.
Claim 3
Dependent Claim 52 words
A high color rendering flourescent lamp in accordance with claim 1, wherein said phosphors in said first phosphor layer consist of at least one selected from the group consisting of a phosphor of an alkaline earth metal halophosphate activated by antimony-manganese and a phosphor of alkaline earth metal halophosphate activated by antimony.
Claim 4
Dependent Claim 44 words
A high color rendering fluorescent lamp in accordance with claim 1, wherein said phosphors in said first phosphor layer consists of a phosphor of an alkaline earth metal halophosphate activated by antimony-manganese and a phosphor of a barium-magnesium aluminate activated by a divalent europium.

References Cited (Backward Citations)

US3569764A Cited
US4088923A Cited
US4267485A Cited
US4431942A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-11-09 1991-05-11 1991-11-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-11-09 1995-05-11 1995-11-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-11-09 1999-05-11 1999-11-10 $7700.00 Window Closed / Lapsed

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