Illumination device and method for manufacturing the same

• US 7,804,102 B2
• Filed: 10/29/2008
• Issued: 09/28/2010
• Est. Priority Date: 10/29/2007
• Status: Expired due to Fees

• Current Assignee: Citizen Electronics Company Limited
• Original Assignee: Citizen Electronics Company Limited
• Inventors: Fukasawa, Koichi, Kadotani, Norikazu, Ishii, Hirohiko
• Primary Examiner(s): Ngo; Ngan
• Application Number:
  US12/260,918
• Publication Number:
  US 20090108283A1
• Time in Patent Office: 699 Days
• Field of Search: 257/98, 257/99, 257/100, 257/E33.059, 257/E33.061, 257/E33.072
• US Class Current: 257/98
• 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: F21K 9/61 using light guides
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 6/0023 provided by one optical element, or plurality thereof, placed between the light guide and the light source, or around the light source
• CPC Class Codes: G02B 6/0055 Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0065 Manufacturing aspects; Material aspects
• CPC Class Codes: G02B 6/0078 Side-by-side arrangements, e.g. for large area displays
• CPC Class Codes: G02B 6/0083 Details of electrical connections of light sources to drivers, circuit boards, or the like
• CPC Class Codes: H01L 2224/48091 Arched
• 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 33/60 Reflective elements

Abstract

An illumination device includes a circuit board (11), an LED element (12) mounted on the circuit board, a light-transmitting sealing resin (16) covering the LED element and containing a fluorescent material, a light reflector (14) covering the light-transmitting sealing resin and reflecting light emitted from the LED element, and a light-guiding part (13) comprising a light-transmitting plate connected to the light-transmitting sealing resin, the light-guiding part guiding the light emitted from the LED element and including a light emission surface (13a) configured to emit the light.

Claims

1. An illumination device, comprising:

a circuit board having a mount surface;

at least one light-emitting diode element mounted on the mount surface of the circuit board;

a light-transmitting sealing resin mounted on the mount surface, covering the light-emitting diode element and containing at least one kind of fluorescent material, the light-transmitting sealing resin having peripheral surfaces, and a light-emitting surface that faces the mount surface of the circuit board and;

a light reflector layered on and covering the peripheral surfaces of the light-transmitting sealing resin except the light-emitting surface, and the light reflector configured to reflect light thereon, after the light emitted from the light-emitting diode element in the light-transmitting sealing resin; and

a light-transmitting plate connected to light-emitting surface of the light-transmitting sealing resin,

the light-transmitting plate including at least one light emission surface, and the light-transmitting plate that receives light through the light-emitting surface of the light-transmitting sealing resin.

2. The illumination device according to claim 1, further comprising;

the light reflector defined as a first light reflector;

the light emission surface of the light-transmitting plate being disposed substantially perpendicular to the mount surface on which the light-emitting diode element is mounted, and

a second light reflector being layered on surfaces of the light-transmitting plate except the light emission surface and a surface contacting the light-emitting surface of the light-transmitting sealing resin.

3. The illumination device according to claim 1, further comprising;

the light reflector defined as a first light reflector;

the light emission surface of the light-transmitting plate being substantially perpendicular to the mount surface of the circuit board, the mount surface on which the light-emitting diode element is mounted, and

a second light reflector is disposed on surfaces of the light-transmitting plate except the light emission surface.

4. The illumination device according to claim 2,

each of the first light reflector and the second light reflector includes one selected from a metallic layer and a light-reflecting resin layer.

5. The illumination device according to claim 2,

further comprising a mother board disposed perpendicularly to the mount surface of the circuit board,

at least one of a light-reflecting layer and a colored layer provided on a surface of the mother board, the surface facing the light-transmitting plate.

6. The illumination device according to claim 5,

wherein the colored layer comprises a light sensitive material.

7. The illumination device according to claim 5,

wherein the light-reflecting layer is one of a metallic film and a light-reflecting resin film.

8. An illumination device, comprising:

a circuit board having a mount surface and electrodes;

at least one light-emitting diode element mounted on the mount surface of the circuit board and electrically connected to the electrodes;

a light-transmitting sealing resin provided on the mount surface and sealing the light-emitting diode element and including a light-emitting surface opposing to the mount surface, a contact surface in contact with the mount surface and peripheral surfaces disposed between the light-emitting surface and the contact surface;

a first light reflector layered on the peripheral surfaces of the light-transmitting sealing resin;

a light-transmitting plate coupled to the light-emitting surface of the light-transmitting sealing resin and including a coupled surface coupled to the light-transmitting sealing resin, an opposing surface that opposes the coupled surface and peripheral surfaces disposed between the coupled surface and the opposing surface;

a light-emitting surface provided on at least one of the opposing surface and the peripheral surfaces of the light-transmitting plate; and

a second light reflector configured to cover the opposing surface and the peripheral surfaces of the light-guiding plate other than the light-emitting surface.

9. The illumination device according to claim 8,

further comprising a mother board disposed perpendicularly to the mount surface of the circuit board and facing one of the peripheral surfaces of the light-guiding plate,

at least one of a light-reflecting layer and a colored layer provided on a surface of the mother board, the surface facing one of the peripheral surfaces of the light-transmitting plate as at least one of the second light reflector.

10. The illumination device according to claim 9,

wherein the colored layer has light sensitivity.

11. The illumination device according to claim 8,

wherein at least one of the first light reflector and the second light reflector comprises one selected from a metallic film and a light-reflecting white-colored film.