US5841177A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multicolor light emitting device
Assignee: Toshiba Corp
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Filing: 1997-07-10
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Granted: 1998-11-24
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Expires: 2017-07-10
Abstract
Abstract A semiconductor light emitting device includes at least two semiconductor light emitting elements which emit different colors of light to each other. The device further includes a lead frame for supporting the light emitting elements and a resin molding for sealing these elements. The external form of this resin molding is an ellipsoid or a part of an ellipsoid in which the curvature in the perpendicular direction to the element row is designed to be smaller than that in the parallel direction to the row. As a result, the device has a widely spread mixed color range especially in the perpendicular direction to the element row and high luminous intensity especially in the parallel direction to the element row. So, a multicolor light emitting device having a high ability of color mixture as well as high luminous intensity can be obtained.
Inventors
- 👤 Satoshi Komoto
- 👤 Toshiaki Tanaka
- 👤 Norio Fujimura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 21:47
CPC Classifications
H; H10; H10W; H10W90/00; H10H; H10H20/00; H10H20/80; H10H20/85; H10H20/852; H10H20/853; H10W72/00; H10W72/50; H10W72/551; H10W72/552; H10W72/5522; H10W74/00; H10W90/701; H10W90/751; H10W90/756
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
175 words
A light emitting device, comprising: a plurality of semiconductor light emitting elements aligned in a row for emitting at least two different colors of light; a lead frame connected with said semiconductor light emitting elements for supplying electric energy to said semiconductor light emitting elements; and a transparent molding for sealing said semiconductor light emitting elements and providing an exterior convex ellipsoidal surface through which the light rays of said at least two different colors are passed, a cross section of said molding containing said light emitting elements being an ellipse having a major axis parallel to said row of semiconductor elements and a minor axis perpendicular to said row of elements, said exterior convex ellipsoidal surface having a long radius of exterior surface curvature in the direction of the major axis and a short radius in the direction of the minor axis, thereby to provide a region of enhanced color mixture of the light rays passed through the exterior convex ellipsoidal surface corresponding to a ratio of the long radius to the short radius.
Claim 2
Dependent Claim
175 words
A light emitting device, comprising: a plurality of semiconductor light emitting elements aligned in a row for emitting at least two different colors of light; a lead frame connected with said semiconductor light emitting elements for supplying electric energy to said semiconductor light emitting elements; and a transparent molding for sealing said semiconductor light emitting elements and providing an exterior convex ellipsoidal surface through which the light rays of said at least two different colors are passed, a cross section of said molding containing said light emitting elements being an ellipse having a major axis parallel to said row of semiconductor elements and a minor axis perpendicular to said row of elements, said exterior convex ellipsoidal surface having a long radius of exterior surface curvature in the direction of the major axis and a short radius in the direction of the minor axis, thereby to provide a region of enhanced color mixture of the light rays passed through the exterior convex ellipsoidal surface corresponding to a ratio of the long radius to the short radius.
Claim 3
Dependent Claim
41 words
The multicolor light emitting device as claimed in claim 1, including at least three spaced and aligned semiconductor light emitting elements, one of which emits red light, another of which emits green light, and the other of which emits blue light.
Claim 4
Dependent Claim
51 words
The multicolor light emitting device as claimed in claim 1, wherein said resin molding is so formed that the ratio of the long radius of exterior surface curvature in the direction parallel to the major axis, to the short radius in the direction of the minor axis, is more than 1.2.
Claim 5
Dependent Claim
52 words
The multicolor light emitting device as claimed in claim 3, wherein said at least three semiconductor light emitting elements include a GaAlAs or GaAsP light emitting diode for generating red light, a GaP or InGaAlP light emitting diode for generating green light, and a SiC light emitting diode for generating blue light.
References Cited (Backward Citations)
JPS5882581A
Cited
JPS61163673A
Cited
JPH03171681A
Cited
JPH03179787A
Cited
JPH04137772A
Cited
US5266817A
Cited
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| 3.5 Years (Year 4) | 2001-11-23 | 2002-05-25 | 2002-11-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-11-23 | 2006-05-25 | 2006-11-24 | $3760.00 | Window Closed / Lapsed |
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