Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
  • H01J61/00—Gas-discharge or vapour-discharge lamps
  • H01J61/02—Details
  • H01J61/38—Devices for influencing the colour or wavelength of the light
  • H01J61/42—Devices for influencing the colour or wavelength of the light by transforming the wavelength of the light by luminescence
  • H01J61/44—Devices characterised by the luminescent material
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
  • C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
  • C09K11/74—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing arsenic, antimony or bismuth
  • C09K11/75—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing arsenic, antimony or bismuth containing antimony
  • C09K11/76—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing arsenic, antimony or bismuth containing antimony also containing phosphorus and halogen, e.g. halophosphates
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
  • C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
  • C09K11/77—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals
  • C09K11/7728—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals containing europium
  • C09K11/7737—Phosphates
  • C09K11/7738—Phosphates with alkaline earth metals
  • C09K11/7739—Phosphates with alkaline earth metals with halogens
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
  • H01J61/00—Gas-discharge or vapour-discharge lamps
  • H01J61/02—Details
  • H01J61/38—Devices for influencing the colour or wavelength of the light

Definitions

• This invention relates to daylight fluorescent lamps and the two phosphor components incorporated therein. More particularly, it relates to lamps containing two phosphor components that yield higher lumens per watt with a suitable color rendition than prior standard day ⁇ light lamp.
• the color characteristics of light emitted from a fluorescent lamp depends on the choice of phosphors used to coat the internal walls of lamp envelope. Emission spectra of luminescence centers in most phosphors consist of a single band peak at one particular wavelength. Therefore, in order to have white light it is necessary to * either apply a mixture of phosphors or use a single phosphor containing more than one kind of luminescent center (such as the alkaline earth halophosphates) . It is not enough to obtain the desired chromaticity coordi ⁇ nates and there are an infinite number of possible combi ⁇ nations of bands that would result in the same set of coordinates. It is also necessary that the lamp produce
• OMPI wip ⁇ ⁇ an acceptable luminous flux (brightness) and satisfactory optimum color rendition for all regions of the visible spectrum.
• lamps are equiva ⁇ lent to the prior daylight lamps in chromaticity use less energy to yield comparable brightness and having a suit ⁇ able color rendition are achieved by uitlizing specific two-component phosphor systems that consist essentially of a first component having a specific peak emission in the yellow region and a specific bandwidth, and a second component having a specific peak emission in the blue region with a specific bandwidth.
• specific two-component phosphor systems consist essentially of a first component having a specific peak emission in the yellow region and a specific bandwidth, and a second component having a specific peak emission in the blue region with a specific bandwidth.
• Figure 1 is a fluorescent lamp having the phosphor system of this invention deposited as a coating on the internal surfaces of the lamp envelope.
• Figure 2 is a portion of the CIE chromaticity dia ⁇ gram containing information helpful in explaining the present invention.
• Figure 3 is a reproduction of the complete CIE chromaticity diagram.
• the blue emitting component has a relatively narrow bandwidth and a peak emission in the range of from about 440 to 450 nanometers. A broader band emitter would cause a loss in visible light and a shift in peak emission.
• Alkaline earth halophosphates activated with europium are preferred. These materials are represented by the formula, Sr-._ _ Ba Eu Cl(PO.)-, wherein x is from about 0.5 to about 3.0, y is from about 0.005 to about 0.15 and the europium is in the divalent state. Chlorine is the preferred halogen.
• the yellow emitting phosphor composition useful in this invention can be represented by the formula
• the materials have a peak wavelength of from about 540 to about 570 nanometers and a 50% bandwidth of from about 60 to about 100 nanometers.
• Line B represents the chromaticity coordinates for compositions having the formula
• Line C represents the chromaticity coordinates for compositions having the formula
• the emission from the mercury has to be considered in the overall chromaticity of emis- sion of the lamp.
• the mercury emission is considered the effective chromaticity of the yellow emission cause the emissions falling along line B and C to shift to those falling along lines D and E respectively.
• the sealed glass envelope 1 has the lead-in wires 2, 3, sealed through one of its ends and corresponding lead-in wires sealed through the other end.
• the usual coiled- coil 4 of tungsten wire is supported between, and elec ⁇ trically connected to, the pair of lead-in wires 2, 3, and a similar coil is supported by and connected to the lead-in wires at the other end of the envelope 1.
• the tungsten coils carry the usual electron-emitting coating of alkaline earth oxides, generally including also a small percentage of zirconium dioxide.
• the lamp has the usual stem press 14 and sealed exhaust tube 15.
• a layer 13 of the two component phosphor system described herein On the inside surface of the envelope, is a layer 13 of the two component phosphor system described herein. Under present lamp manufacturing methods it is preferred to use a relatively uniform blend of the two component system, however, the present invention is not so limited. It is merely necessary that each of the phosphors be uniformly distributed over the internal surface of the glass envelope.
• OMP - V/IF ponents chosen.
• the amount of each * component would be inversely proportional to the dis ⁇ tances each of the phosphors are from the aforementioned daylight target.
• corrections must be made for the relative quantum efficiencies of the individual phosphors.
• the individual phosphors can be applied to the envelope as separate layers in which case due to the inner layer being exposed to the more intense ultra- violet radiation the amount of the phosphor chosen as the inner layer is reduced from that required in a blend.
• the amount can be about 10% of that required in when a uniform blend is used. Therefore in the case where the blue com ⁇ ponent is used as the inner layer from about 3% to about 30% of the total phosphor component would be the blue emit ⁇ ting phosphor.
• from about 3% to about 96% of the total phosphor content is the blue emitting phosphor and the balance is yellow emitting phosphor depending upon the method used to deposit the phosphors.
• the present invention is directed to a fluorescent lamp having desirable properties for providing suitable illumination.

Landscapes

• Chemical & Material Sciences (AREA)
• Inorganic Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Organic Chemistry (AREA)
• Vessels And Coating Films For Discharge Lamps (AREA)
• Luminescent Compositions (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=21970467

Family Applications (1)

Country Status (6)

Cited By (3)

Families Citing this family (8)

Citations (2)

Family Cites Families (11)

• 1979
  • 1979-06-22 US US06/051,305 patent/US4458176A/en not_active Expired - Lifetime
• 1980
  • 1980-05-16 JP JP55501459A patent/JPH023837B2/ja not_active Expired
  • 1980-05-16 DE DE8080901241T patent/DE3063757D1/de not_active Expired
  • 1980-05-16 WO PCT/US1980/000589 patent/WO1981000028A1/en not_active Ceased
  • 1980-06-18 CA CA000354245A patent/CA1148207A/en not_active Expired
• 1981
  • 1981-01-12 EP EP80901241A patent/EP0030956B1/en not_active Expired

Patent Citations (2)

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