Title:
LIGHT EMITTING DEVICE AND ILLUMINATION DEVICE
Document Type and Number:
WIPO Patent Application WO/2008/020541
Kind Code:
A1
Abstract:
Provided is a white LED of a high color rendering characteristic having an average
color rendering evaluation value exceeding 90 by using a blue LED element. The
white LED includes a semiconductor light emitting element emitting a blue light
or blue-violet light and a fluorescent material absorbing a part or whole of the
light emitted from the semiconductor light emitting element and emitting a fluorescent
light of a wavelength different from the light. The fluorescent material is
a mixed fluorescent material obtained by mixing a first fluorescent material
emitting a blue-green light or a green light, a second fluorescent material having
a light emitting peak wavelength longer than the first fluorescent material
and emitting a green light or a yellow-green light, a third fluorescent material
having a light emitting peak wavelength longer than the second fluorescent material
and emitting a yellow-green light, a yellow light, or a yellow-red light, and
a fourth fluorescent material having a light emitting peak wavelength longer
than the third fluorescent material and emitting a yellow-red light or a red light.
Inventors:
KIMURA NAOKI (JP)
SUZUKI RYUJI (JP)
SAKUMA KEN (JP)
HIROSAKI NAOTO (JP)
SUZUKI RYUJI (JP)
SAKUMA KEN (JP)
HIROSAKI NAOTO (JP)
Application Number:
PCT/JP2007/064861
Publication Date:
February 21, 2008
Filing Date:
July 30, 2007
Export Citation:
Assignee:
FUJIKURA LTD (JP)
NAT INST FOR MATERIALS SCIENCE (JP)
KIMURA NAOKI (JP)
SUZUKI RYUJI (JP)
SAKUMA KEN (JP)
HIROSAKI NAOTO (JP)
NAT INST FOR MATERIALS SCIENCE (JP)
KIMURA NAOKI (JP)
SUZUKI RYUJI (JP)
SAKUMA KEN (JP)
HIROSAKI NAOTO (JP)
International Classes:
C09K11/08; C09K11/59; C09K11/64; H01L33/50
Domestic Patent References:
| WO2001089001A2 | 2001-11-22 | |||
| WO2005087896A1 | 2005-09-22 |
Foreign References:
| JP2006080443A | 2006-03-23 | |||
| JP2005285800A | 2005-10-13 | |||
| JP2006176546A | 2006-07-06 | |||
| EP1630220A2 | 2006-03-01 | |||
| EP1278250A2 | 2003-01-22 | |||
| JP2007180377A | 2007-07-12 | |||
| JP2006221062A | 2006-08-24 | |||
| JP2900928B2 | 1999-06-02 | |||
| JP2927279B2 | 1999-07-28 | |||
| JP2003273409A | 2003-09-26 | |||
| JP2003321675A | 2003-11-14 | |||
| JPH10163535A | 1998-06-19 | |||
| JP2000509912A | 2000-08-02 | |||
| JP2002363554A | 2002-12-18 |
Other References:
K. BANDO ET AL.: "Development of High-bright and Pure-white LED Lamps", J. LIGHT & VIS. ENV., vol. 22, no. 1, 1998, pages 2 - 5
M. YAMADA ET AL.: "Red-Enhanced White-Light-Emitting Diode Using a New Red Phosphor", JPN. J. APPL. PHYS., vol. 42, 2003, pages L20 - L23, XP001191982, DOI: doi:10.1143/JJAP.42.L20
PAUL S. MARTIN: "Performance, Thermal, Cost & Reliability challenges for Solid State Lighting", OIDA CONFERENCE, 30 May 2002 (2002-05-30)
R. J. XIE ET AL.: "Eu2+-doped Ca-a SiAlON: A yellow phosphor for white light-emitting diodes", APPL. PHYS. LETT., vol. 84, 2004, pages 5404 - 5406, XP012073129, DOI: doi:10.1063/1.1767596
K. SAKUMA ET AL.: "Warm-white light-emitting diode with yellowish orange SiAlON ceramic phosphor", OPT. LETT., vol. 29, 2004, pages 2001 - 2003, XP002596937, DOI: doi:10.1364/OL.29.002001
See also references of EP 2056366A4
M. YAMADA ET AL.: "Red-Enhanced White-Light-Emitting Diode Using a New Red Phosphor", JPN. J. APPL. PHYS., vol. 42, 2003, pages L20 - L23, XP001191982, DOI: doi:10.1143/JJAP.42.L20
PAUL S. MARTIN: "Performance, Thermal, Cost & Reliability challenges for Solid State Lighting", OIDA CONFERENCE, 30 May 2002 (2002-05-30)
R. J. XIE ET AL.: "Eu2+-doped Ca-a SiAlON: A yellow phosphor for white light-emitting diodes", APPL. PHYS. LETT., vol. 84, 2004, pages 5404 - 5406, XP012073129, DOI: doi:10.1063/1.1767596
K. SAKUMA ET AL.: "Warm-white light-emitting diode with yellowish orange SiAlON ceramic phosphor", OPT. LETT., vol. 29, 2004, pages 2001 - 2003, XP002596937, DOI: doi:10.1364/OL.29.002001
See also references of EP 2056366A4
Attorney, Agent or Firm:
SHIGA, Masatake et al. (Yaesu Chuo-k, Tokyo 53, JP)
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