Light source unit

• US 20050023551A1
• Filed: 07/30/2004
• Published: 02/03/2005
• Est. Priority Date: 08/01/2003
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Inventors: Mizuyoshi, Akira
• Granted Patent: US 7,021,799 B2
• Time in Patent Office: Days
• US Class Current: 257/99
• CPC Class Codes: B41J 2/45 using light-emitting diode [LED] or laser arrays
• CPC Class Codes: F21V 29/67 characterised by the arrangement of fans
• CPC Class Codes: F21V 29/677 the fans being used for discharging
• CPC Class Codes: F21V 29/76 with essentially identical parallel planar fins or blades, e.g. with comb-like cross-section
• CPC Class Codes: F21V 29/763 the planes containing the fins or blades having the direction of the light emitting axis
• CPC Class Codes: F21Y 2105/10 comprising a two-dimensional array of point-like light-generating elements
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/49107 on the semiconductor or solid-state body
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• 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 2924/00014 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 2924/3025 Electromagnetic shielding
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H01L 33/642 characterized by the shape

Abstract

Light-emitting element arrays having aligned LEDs are fixed to a stand integrally formed with a heat sink. An attachment surface of the stand is formed with V-shaped grooves working as reflection planes for improving irradiation efficiency. The arrays are separated from printed-circuit boards to be bonded therewith by wires. The array is placed at the bottom of the groove. The printed-circuit board is placed on a step formed at a wall of the groove. Since the array is separated from the resinous printed-circuit board having inferior heat conductance, high efficiency of heat radiation is obtained. Further, since the array is disposed close to the wall, unevenness of intensity distribution of the LEDs is prevented from being enlarged.

Claims

1. A light source unit comprising:

at least one light-emitting element array having a plurality of light-emitting elements arranged in line;

a printed-circuit board provided separately from said light-emitting element array, and having a printed circuit pattern to be bonded with said light-emitting element array by wires; and

an attachment stand to which said light-emitting element array and said printed-circuit board are fixed, said attachment stand being formed with a substantially V-shaped groove for placing said light-emitting element array, and a side wall of said groove being disposed as a reflection plane in a longitudinal direction of said light-emitting element array,

wherein said light-emitting element array is placed on a bottom surface of said groove, and said printed-circuit board is placed on a step formed at a part of said side wall of said groove.

2. A light source unit according to claim 1, wherein said light-emitting element array has one of a plate and a sheet for fixing said light-emitting elements, and said light-emitting element array is fixed to said attachment stand via one of said plate and said sheet.

3. A light source unit according to claim 1, wherein said light-emitting element is directly attached to said bottom surface of said groove.

4. A light source unit according to claim 1, wherein said groove is covered with a reflection coating formed from a metal and a dielectric.

5. A light source unit according to claim 1, wherein said light-emitting element is a chip-type element substantially having a parallelepiped shape, and the respective light-emitting elements are disposed so as to prevent lateral surfaces of the adjacent light-emitting elements from confronting each other.

6. A light source unit according to claim 1, wherein said attachment stand is integrally formed with a heat sink.

7. A light-source unit according to claim 6, wherein a fun is fixed to said heat sink.

8. A light source unit according to claim 1, wherein at least two kinds of said light-emitting element arrays are provided to radiate rays having different wavelengths.

9. A light source unit according to claim 1, wherein said light-emitting element array is sealed with a transparent resin infused into said groove.

10. A light source unit according to claim 1, wherein said light-emitting element is a light-emitting diode.

11. A light source unit according to claim 1, further comprising:

an air intake fan for sending air to said groove, said air intake fan being fixed to one side plate of said attachment stand in said longitudinal direction; and

an exhaust port formed in the other side plate of said attachment stand in said longitudinal direction.