| US 7,611,780 B2 | ||
| Lighting device, image pickup apparatus and portable terminal unit | ||
| Hiroki Iwanaga, Yokohama (Japan); Akio Amano, Kawasaki (Japan); Kenji Shimomura, Kawasaki (Japan); and Kazuaki Otsuka, Yokosuka (Japan) | ||
| Assigned to Kabushiki Kaisha Toshiba, Tokyo (Japan) | ||
| Filed on Feb. 07, 2006, as Appl. No. 11/348,412. | ||
| Claims priority of application No. 2005-092289 (JP), filed on Mar. 28, 2005. | ||
| Prior Publication US 2006/0214578 A1, Sep. 28, 2006 | ||
| Int. Cl. B32B 9/00 (2006.01) | ||
| U.S. Cl. 428—690 [345/83; 257/100] | 19 Claims |
| 1. A lighting device comprising:
a supporting member;
a plurality of light emitting element disposed on the supporting member, and each emitting light from an upper and side surfaces
thereof;
a first fluorescent layer containing an organic phosphor and disposed on the supporting member; and
a second fluorescent layer containing only an inorganic phosphor and disposed on the upper surface of the supporting member;
wherein the second fluorescent layer is disposed to cover the upper and side surfaces of the light emitting element, and the
first fluorescent layer is disposed on at least side surface of the light emitting element with the second fluorescent layer
being interposed between the light emitting element and the first fluorescent layer,
wherein the organic phosphor is a trivalent europium complex,
wherein the europium complex has a structure represented by the following formula (2):
 wherein R1-R7 are individually selected from the group consisting of a linear or branched alkyl or alkoxy group each having not more than
20 carbon atoms, phenyl group, biphenyl group, naphthyl group, heterocyclic group, substitution products of foregoing groups,
hydrogen atom and deuterium atom with a proviso that all of R1-R4 are not the same with each other; and n is an integer of 2 or more.
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