ALTERNATIVE CURRENT LIGHT-EMITTING SYSTEMS

• US 20110074305A1
• Filed: 12/09/2010
• Published: 03/31/2011
• Est. Priority Date: 05/13/2005
• Status: Active Grant

• Current Assignee: Epistar Corporation
• Original Assignee: Epistar Corporation, Industrial Technology Research Institute
• Inventors: Yeh, Wen-Yung, Yu, Yu-Chen, Lin, Jui-Ying, Yen, Hsi-Hsuan
• Granted Patent: US 9,490,234 B2
• Time in Patent Office: Days
• US Class Current: 315/253
• 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: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 25/167 comprising optoelectronic devices, e.g. LED, photodiodes
• CPC Class Codes: H01L 27/15 including semiconductor components having potential barriers, specially adapted for light emission
• 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 33/36 characterised by the electrodes
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls

Abstract

A light-emitting system is introduced herein. The light-emitting system includes a substrate and a plurality of light-emitting units electrically-connected on the substrate. Each of the plurality of light-emitting units includes a plurality of light-emitting diodes arranged as a bridge rectifier. A first part of the plurality of light-emitting diodes emits light during positive half cycles of an AC power signal. A second part of the plurality of light-emitting diodes emits light during negative half cycles of the AC power signal. The third part of the plurality of light-emitting diodes comprising at least one light-emitting diode emits light during both the positive half cycles and the negative half cycles of the AC power signal.

Claims

1. A light-emitting system, comprising:

a substrate; and

a plurality of light-emitting units electrically-connected on the substrate, wherein each of the plurality of light-emitting units comprises a plurality of light-emitting diodes arranged as a bridge rectifier comprising

a first part of the plurality of light-emitting diodes emit light during positive half cycles of an AC power signal;

a second part of the plurality of light-emitting diodes emit light during negative half cycles of the AC power signal; and

a third part of the plurality of light-emitting diodes comprising at least one light-emitting diode emits light during both the positive half cycles and the negative half cycles of the AC power signal.

2. The light-emitting system of claim 1, wherein the light-emitting units are electrically connected in series.

3. The light-emitting system of claim 1, wherein the total number of the first part of the plurality of light-emitting diodes and the second part of the plurality of light-emitting diodes are approximately 1 to 2.5 times of the number of the third part of the light emitting diodes.

4. The light-emitting system of claim 1, wherein the effective size of the light emitting diodes in the first part or in the second part is approximately 0.5 to 1.5 times of the effective size of the light emitting diodes in the third part.

5. The light-emitting system of claim 1, wherein at least one of the plurality of light-emitting units comprises at least one Schottky diode.

6. The light-emitting system of claim 1, wherein the at least one of the plurality of light-emitting diodes comprises more than one active layer.

7. The light-emitting system of claim 6, wherein each of the active layers of the light emitting diodes emits light of identical wavelength.

8. The light-emitting system of claim 1, wherein the plurality of light-emitting diodes in the third part comprises at least two light-emitting active layers coupled in at least one of a series connection and a parallel connection.

9. The light-emitting system of claim 8, wherein the at least two light-emitting active layers emit lights of different wavelengths.

18. The light-emitting system of claim 1, wherein the plurality of light-emitting units is in a chip.

10. A light-emitting system, comprising:

a substrate; and

a plurality of light-emitting units formed on the substrate, each of the plurality of light-emitting units comprising a plurality of light emitting diodes, wherein

a first part and a third part of the plurality of light-emitting units are coupled to a first current path, and a second part and the third part of the plurality of light-emitting units are coupled to a second current path, thereby the plurality of light-emitting diodes in the first part and the third part and the plurality of light-emitting diodes in the second part and the third part emit light alternatively when an AC power signal is applied to the light-emitting system.

11. The light-emitting system of claim 10, wherein the plurality of light-emitting units are electrically connected in series.

12. The light-emitting system of claim 10, wherein the total number of the first part and the second part of the plurality of light-emitting diodes are approximately 1 to 2.5 times of the number of the third part of the plurality of light emitting diodes.

13. The light-emitting system of claim 10, wherein the effective size of the plurality of light emitting diodes in the first part or in the second part is approximately 0.5 to 1.5 times of the effective size of the plurality of light emitting diodes in the third part.

14. The light-emitting system of claim 10, wherein at least one of the plurality of light-emitting units comprises at least one Schottky diode.

15. The light-emitting system of claim 10, wherein the at least one of the plurality of light-emitting diodes comprises more than one active layers.

16. The light-emitting system of claim 15, wherein each of the active layers of the at least one of the plurality of light emitting diodes emits light of identical wavelength.

17. The light-emitting system of claim 15, wherein the more than one active layers emit lights of different wavelengths.

19. The light-emitting system of claim 10, wherein the plurality of light-emitting units is in a chip.