Safe light emitting device

• US 6,505,954 B2
• Filed: 06/18/2001
• Issued: 01/14/2003
• Est. Priority Date: 06/18/2001
• Status: Expired due to Fees

• Current Assignee: Excellence Opto. Inc (Excellence Optoelectronics Inc.)
• Original Assignee: Excellence Opto. Inc (Excellence Optoelectronics Inc.)
• Inventors: Chen, Yen-Cheng
• Primary Examiner(s): O'Shea, Sandra
• Assistant Examiner(s): Sawhney, Hargobind S.
• Application Number:
  US09/881,704
• Publication Number:
  US 20020191393A1
• Time in Patent Office: 575 Days
• Field of Search: 362/21, 362/276, 362/234, 362/227, 362/800, 315/119, 315/193, 315/120, 315/121, 315/122, 315/123, 315/125, 315/126, 315/185.S, 315/185.R
• US Class Current: 362/234
• CPC Class Codes: F21S 4/10 with light sources attached to loose electric cables, e.g. Christmas tree lights
• CPC Class Codes: F21V 25/04 breaking the electric circuit
• CPC Class Codes: F21V 25/10 coming into action when lighting device is overloaded, e.g. thermal switch
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 25/167 comprising optoelectronic devices, e.g. LED, photodiodes
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/3011 Impedance
• CPC Class Codes: H05B 45/30 Driver circuits
• CPC Class Codes: H05B 45/40 Details of LED load circuits
• CPC Class Codes: H05B 45/54 in a series array of LEDs
• CPC Class Codes: H05B 45/56 involving measures to prevent abnormal temperature of the LEDs
• CPC Class Codes: H05B 47/23 of two or more light sources connected in series
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

The present invention provides a safe light emitting device that can avoid danger of explosion and fire whenever over current or over voltage occurs. The light emitting device includes a plurality of light emitting diode lamps in series. At least one of the light emitting diode lamps is a safe light emitting diode lamp. The safe light emitting diode lamp results in a broken circuit when either over current or over voltage in the light emitting device occurs. Through the incorporation of the safe light emitting diode lamp, the series light emitting device will automatically fail whenever over current or over voltage occurs and thus be prevented from explosion and fire.

Claims

1. A light emitting device including a plurality of light emitting diode lamps in series;

wherein at least one of the light emitting diode lamps is a safe light emitting diode lamp, said safe light emitting diode lamp comprising;

a light emitting diode chip;

a lead frame; and

a chip type resistor, said chip type resistor being disposed between said light emitting diode chip and said lead frame;

whereby said safe light emitting diode lamp is configured to provide a broken circuit when either over current or over voltage in said light emitting device occurs.

2. The light emitting device of claim 1, wherein the chip type resistor results in a broken circuit when either over voltage or over current in the light emitting device occurs.

3. The light emitting device of claim 1, wherein the safe light emitting diode lamp further comprises a bonding wire between the light emitting diode chip and type resistor.

4. The light emitting device of claim 1, wherein said chip type resistor is configured to withstand a voltage drop to said light emitting device to provide surge protection.

5. The light emitting device of claim 1, wherein said chip type resistor is configured to restrict the temperature of said chip type resistor by a tolerance temperature limit.

6. A light emitting device including a plurality of light emitting diode lamps in series;

wherein at least one of the light emitting diode lamps is a safe light emitting diode lamp, said safe light emitting diode lamp comprising;

a light emitting diode chip;

a lead frame;

a chip type resistor, said chip type resistor being disposed between said light emitting diode chip and said lead frame; and

a bonding wire between said light emitting diode chip and said chip type resistor, said chip type resistor being connected to said light emitting diode chip via said bonding wire;

whereby said safe light emitting diode lamp is configured to provide a broken circuit when either over current or over voltage in said light emitting device occurs.

7. The light emitting device of claim 6, wherein said chip type resistor is configured to provide a broken circuit when either over voltage or over current in the light emitting device occurs.

8. The light emitting device of claim 6, wherein said chip type resistor is configured to withstand a voltage drop to said light emitting device to provide surge protection.