Title:
LOW PRESSURE MERCURY VAPOR DISCHARGE LAMP
Document Type and Number:
Japanese Patent JPS5942758
Kind Code:
A
Abstract:
A low-pressure mercury vapor discharge lamp having a satisfactory color rendition (Ra>/=80), a color temperature of 2800 DEG K. or higher and a color point on or near the Planckian locus. The lamp is provided with a luminescent layer (4) which comprises a. a luminescent rare earth metal metaborate activated by Ce and Mn and having a fundamental lattice Ln(Mg,Zn,Cd)B5O10, where Ln represents the elements Y, La and/or Gd, which borate exhibits red Mn emission, b. a luminescent material activated by Tb3+ and having green Tb3+ emission, c. at least one luminescent halophosphate of the group which comprises the calcium halophosphates emitting white light, activated by Sb3+ and Mn2+ and having a color temperature of at least 2900 DEG K. and blue-luminescing calcium halophosphate activated by Sb3+. The lamps yield a satisfactory rendition of deep red colors (R9>/=60) and have a high luminous flux and a high maintenance of the luminous flux during the life.
Inventors:
YOHANNESU TEODORUSU UIRUHERUMU
YOHANNESU TORUDO KOONERISU FUA
EBERUHARUDASU FURADASU BERUNSU
YOHANNESU TORUDO KOONERISU FUA
EBERUHARUDASU FURADASU BERUNSU
Application Number:
JP13599983A
Publication Date:
March 09, 1984
Filing Date:
July 27, 1983
Export Citation:
Assignee:
PHILIPS NV
International Classes:
C09K11/08; H01J61/38; H01J61/44; (IPC1-7): H01J61/38
Domestic Patent References:
| JPS5628282A | 1981-03-19 | |||
| JPS5674174A | 1981-06-19 |
Attorney, Agent or Firm:
Akihide Sugimura