LED lamp for light source of a headlamp

• US 20040251469A1
• Filed: 09/16/2003
• Published: 12/16/2004
• Est. Priority Date: 06/13/2003
• Status: Active Grant

• Current Assignee: Stanley Electric Company Limited
• Original Assignee: Stanley Electric Company Limited
• Inventors: Owada, Ryotaro, Yatsuda, Yasushi, Koike, Teruo, Ohno, Masafumi, Kushimoto, Takuya, Futami, Takashi, Ebisutani, Takashi
• Granted Patent: US 7,019,334 B2
• Time in Patent Office: Days
• US Class Current: 257/100
• CPC Class Codes: F21K 9/00 Light sources using semiconductor devices as light-generating elements, e.g. using light-emitting diodes [LED] or lasers
• CPC Class Codes: F21S 41/141 Light emitting diodes [LED]
• CPC Class Codes: F21S 41/16 Laser light sources
• CPC Class Codes: F21S 41/43 characterised by the shape thereof
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/19107 off-chip wires
• CPC Class Codes: H01L 2924/3025 Electromagnetic shielding
• CPC Class Codes: H01L 33/52 Encapsulations
• CPC Class Codes: H01L 33/58 Optical field-shaping elements
• CPC Class Codes: H01L 33/60 Reflective elements

Abstract

Whereas incandescent light bulbs and other similar light sources known in the prior art emit light in all directions, LED lamps emit light in a single direction only, and this is manifested in the problem of being unable to achieve light distribution characteristics satisfied by conventional headlamp designs. The present invention realizes an LED lamp for a light source of a headlamp disposing an LED chip 2 in the vicinity of the focus of a projection means and providing a shielding member 6 covering a portion of the LED chip 2 in a formation allowing a light distribution characteristic suitable for a vehicle front-illumination light to be obtained when light from the LED chip 2 is magnified and projected in an illumination direction by a projection lens 10 or the like constituting the projection means; accordingly, accurate light distribution characteristics can be obtained in a simple manner by projecting in the illumination direction using the projection lens 10.

Claims

1. An LED lamp for a light source of a headlamp, characterized in that an LED chip or a white LED light emission portion having an LED lamp and fluorophor is disposed in the vicinity of the focus of a projection means, and a shielding member covering a portion of said white LED light emission portion is provided in a shape allowing a light distribution characteristic suitable for a headlamp of a vehicle to be obtained when light from said white LED light emission portion is magnified and projected in an illumination direction by said projection means.

2. The LED lamp for the light source of the headlamp of claim 1, further characterized in that said shielding member is disposed to form a gap of 2 mm or less from said white LED light emission portion.

3. The LED lamp for the light source of the headlamp of claim 1 or 2, further characterized in that a mirror finish is applied on the surface of said shielding member opposing white LED light emission portion said white LED light emission portion.

4. The LED lamp for the light source of the headlamp of claim 3, further characterized in that the surface on the side of said shielding member on which the mirror finish is applied provides inclines for reflecting light in the direction of non-shielding of said white LED light emission portion.

5. The LED lamp for the light source of the headlamp of any one of claims 1 to 4, further characterized in that said shielding member performs shielding by the portion of said white LED light emission portion in which highest intensity occurs or of an edge passing in the vicinity thereof.

6. The LED lamp for the light source of the headlamp of any one of claims 1 to 5, further characterized in that a wavelength conversion member is interposed between said white LED light emission portion and said shielding member.

7. The LED lamp for the light source of the headlamp of any one of claims 1 to 6, further characterized in that:

said shielding member is integrated with a lens member or window glass member covering said white LED light emission portion.