LIGHT-EMITTING SYSTEMS

• US 20090096386A1
• Filed: 10/07/2008
• Published: 04/16/2009
• Est. Priority Date: 05/13/2005
• Status: Active Grant

• Current Assignee: Epistar Corporation
• Original Assignee: Industrial Technology Research Institute
• Inventors: Yeh, Wen-Yung, Yu, Yu-Chen, Lin, Jui-Ying, Yen, Hsi-Hsuan
• Granted Patent: US 8,704,241 B2
• Time in Patent Office: Days
• US Class Current: 315/294
• 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 includes a first power input terminal and a second power input terminal and five rectifying devices coupled between the two power input terminals. The first and second power input terminals may receive an external power input. The first rectifying device is coupled between the first power input terminal and a first intermediate contact. The second rectifying device is coupled between the second power input terminal and the first intermediate contact. The third rectifying device is coupled between a second intermediate contact and the second power input terminal. The fourth rectifying device is coupled between the second intermediate contact and the first power input terminal. The fifth rectifying device is coupled between the first intermediate contact and the second intermediate contact. The fifth rectifying device is configured to allow a current flow from the first intermediate contact to the second intermediate contact and to emit light in response to the current flow. One or more of the first, second, third, and fourth rectifying devices may include one or more light-emitting diodes, one or more Schottky diode(s), or a combination of both types of diodes.

Claims

1. A light-emitting system comprising:

a first power input terminal and a second power input terminal for receiving an external power input;

a first rectifying device coupled between the first power input terminal and a first intermediate contact, the first rectifying device being configured to allow a current flow from the first power input terminal to the first intermediate contact;

a second rectifying device coupled between the second power input terminal and the first intermediate contact, the second rectifying device being configured to allow a current flow from the second power input terminal to the first intermediate contact;

a third rectifying device coupled between a second intermediate contact and the second power input terminal, the third rectifying device being configured to allow a current flow from the second intermediate contact to the second power input terminal;

a fourth rectifying device coupled between the second intermediate contact and the first power input terminal, the fourth rectifying device being configured to allow a current flow from the second intermediate contact to the first power input terminal; and

a fifth rectifying device coupled between the first intermediate contact and the second intermediate contact, the fifth rectifying device comprising at least one light-emitting micro diode and being configured to allow a current flow from the first intermediate contact to the second intermediate contact and to emit light in response to the current flow, wherein at least one of the first, second, third, and fourth rectifying devices comprises at least one of at least one light-emitting micro diode and at least one Schottky diode.

2. The light-emitting system of claim 1, wherein the total number of the at least one light-emitting micro diode in the first, second, third, and fourth rectifying device is approximately 1 to 2.5 times of the number of the at least one light-emitting micro diode in the fifth rectifying device.

3. The light-emitting system of claim 1, wherein the effective size of the at least one light-emitting micro diode in at least one of the first, second, third, and fourth rectifying devices is approximately 0.5 to 1.5 times of the effective size of the at least one light-emitting micro diode in the fifth rectifying device.

4. The light-emitting system of claim 1, wherein the total number of the at least one Schottky diode in the first, second, third, and fourth rectifying devices is approximately 0.125 to 1 time of the number of the at least one light-emitting micro diode in the fifth rectifying device.

5. The light-emitting system of claim 1, wherein the effective size of the at least one Schottky diode in at least one of the first, second, third, and fourth rectifying devices is approximately 0.1 to 0.4 time of the effective size of the at least one light-emitting micro diode in the fifth rectifying device.

6. The light-emitting system of claim 1, further comprising at least one Zener diode coupled between the first or the second power input terminal and ground.

7. The light-emitting system of claim 1, wherein at least one of the light-emitting micro diodes has at least one active layer.

8. The light-emitting system of claim 7, wherein the fifth rectifying device 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 1, wherein the fifth rectifying device comprises at least two light-emitting micro diodes coupled in at least one of a series connection and a parallel connection.

10. The light-emitting system of claim 1, wherein the light-emitting system comprises at least one capacitor coupled between the first and second power input terminals.

11. The light-emitting system of claim 1 further comprising a first substrate having at least a portion of the first, second, third, fourth, or fifth rectifying device formed over the first substrate and a second substrate having conductive paths formed over the second substrate, the conductive paths being configured to provide conductive couplings to at least one of the first, second, third, fourth, and fifth rectifying devices.

12. The light-emitting system of claim 1, wherein the first and second power input terminals are configured to receive an alternating-current input.

13. The light-emitting system of claim 1, wherein a first input current flowing from the first power input terminal to the second power input terminal flows through the first, fifth, and third rectifying devices, and a second input current flowing from the second power input terminal to the first power input terminal flows through the second, fifth, and fourth rectifying devices to allow the light-emitting system to emit light in response to both the first and second input currents.

14. The light-emitting system of claim 1, wherein numbers of the at least one light-emitting micro diodes or the at least one Schottky diodes in the first, second, third, and fourth rectifying devices are different.

15. A light-emitting system, comprising:

a substrate;

a bridge-circuit connection having at least four branches and being provided over the substrate, each branch having two terminals; and

at least one light-emitting micro diode coupled between the two terminals of each branch, the bridge circuit connection being configured to receive an alternating current input, to enable at least a first group of the light-emitting micro diodes to emit light during positive cycles of the alternating current input, and to enable at least a second group of the light-emitting micro diodes to emit light during negative cycles of the alternating current input; and

wherein the bridge-circuit connection has a central branch having at least one light-emitting micro diode, the central branch being coupled between a first intermediate contact between a first branch and a second branch and a second intermediate contact between a third branch and a fourth branch and being configured to allow a current flow from the first intermediate contact to the second intermediate contact and to emit light in response to the current flow.

16. The light-emitting system of claim 15, wherein at least one Schottky diode in at least one of the at least four branches and being coupled a forward serial coupling with the at least one light-emitting micro diode in the at least one branch,

17. The light-emitting system of claim 16, wherein the total number of the at least one Schottky diode in the first, second, third, and fourth branches is approximately 0.125 to 1 time of the number of the at least one light-emitting micro diode in the central branch.

18. The light-emitting system of claim 16, wherein the effective size of the at least one Schottky diode in at least one of the first, second, third, and fourth branches is approximately 0.1 to 0.4 time of the effective size of the at least one light-emitting micro diode in the central branch.

19. The light-emitting system of claim 15, wherein the total number of the at least one light-emitting micro diode in the first, second, third, and fourth branches is approximately 1 to 2.5 times of the number of the at least one light-emitting micro diode in the central branch.

20. The light-emitting system of claim 15, wherein the effective size of the at least one light-emitting micro diode in at least one of the first, second, third, and fourth branches is approximately 0.5 to 1.5 times of the effective size of the at least one light-emitting micro diode in the central branch.

21. The light-emitting system of claim 15, wherein the at least one light-emitting micro diode in the central branch has two active layers.

22. The light-emitting system of claim 15, wherein the light-emitting system comprises at least one resistor coupled between two power input terminals of the bridge-circuit connection.

23. A light-emitting system, comprising:

a substrate;

a bridge-circuit connection having at least four branches and being provided over the substrate, each branch having two terminals;

at least one light-emitting micro diode coupled between the two terminals of each branch, the bridge circuit connection being configured to receive an alternating current input, to enable at least a first group of the light-emitting micro diodes to emit light during positive cycles of the alternating current input, and to enable at least a second group of the light-emitting micro diodes to emit light during negative cycles of the alternating current input; and

at least one Zener diode in at least one of the at least four branches and being coupled in at least one or a serial and parallel coupling with the at least one light-emitting micro diode in the at least one branch.

24. The light-emitting system of claim 23, wherein the bridge-circuit connection has a central branch having at least one light-emitting micro diode, the central branch being coupled between a first intermediate contact between a first and a second branches and a second intermediate contact between a third and fourth branches and being configured to allow a current flow from the first intermediate contact to the second intermediate contact and to emit light in response to the current flow.

25. The light-emitting system of claim 23, wherein the at least one Zener diode comprises at least one reversely-coupled Zener diode.

26. The light-emitting system of claim 23, wherein the at least one Zener diode comprises at least one forward-coupled Zener diode coupled in series with at least one reversely-coupled Zener diode.

27. A light-emitting system comprising:

a first power input terminal and a second power input terminal for receiving an external power input;

a first rectifying device coupled between the first power input terminal and a first intermediate contact, the first rectifying device being configured to allow a current flow from the first power input terminal to the first intermediate contact;

a second rectifying device coupled between the second power input terminal and the first intermediate contact, the second rectifying device being configured to allow a current flow from the second power input terminal to the first intermediate contact;

a third rectifying device coupled between a second intermediate contact and the second power input terminal, the third rectifying device being configured to allow a current flow from the second intermediate contact to the second power input terminal;

a fourth rectifying device coupled between the second intermediate contact and the first power input terminal, the fourth rectifying device being configured to allow a current flow from the second intermediate contact to the first power input terminal; and

a fifth rectifying device coupled between the first intermediate contact and the second intermediate contact, the fifth rectifying device being configured to allow a current flow from the first intermediate contact to the second intermediate contact.

28. The light-emitting system of claim 27, wherein the fifth rectifying device comprises a plurality of light-emitting micro diodes to emit light in response to the current flow

29. The light-emitting system of claim 27, wherein the first, second, third, and fourth rectifying devices comprises a plurality of light-emitting micro diode.

30. The light-emitting system of claim 27, wherein the first, second, third, and fourth rectifying devices comprises at least one at least one Schottky diode.