Electrical compensation and fault tolerant structure for light emitting device array
First Claim
Patent Images
1. An apparatus comprisinga plurality of light emitting elements grouped in at least a string and connected in series wherein;
- each said light emitting element comprising a first end and a second end;
each of said light emitting element operating to emit light at or above a first onset voltage by conducting an electrical current;
wherein said apparatus further comprises at least a voltage control devices;
wherein said voltage control device operates in a low impedance state or a high impedance state according to the terminal voltage difference between said first end and second end of at least one said light emitting element;
wherein said voltage control device operates in a high impedance state when said voltage difference is between zero and a first breakover voltage, and operates in a low impedance state when said terminal voltage difference reaches or exceeds said first breakover voltage;
wherein said voltage control device conducts negligible amount of current in said high impedance state compared to the current in said light emitting element;
wherein said voltage control device provides at least a current path parallel to at least a said light emitting device when in its low impedance state.
1 Assignment
0 Petitions
Accused Products
Abstract
Light emitting device arrays comprising alternate current routes that redirect supplied current in the event of open circuit due to a damaged light emitting element are provided. Furthermore, passive light emitting device arrays that provide current compensation for lost light output are provided.
-
Citations
28 Claims
-
1. An apparatus comprising
a plurality of light emitting elements grouped in at least a string and connected in series wherein; - each said light emitting element comprising a first end and a second end;
each of said light emitting element operating to emit light at or above a first onset voltage by conducting an electrical current; wherein said apparatus further comprises at least a voltage control devices;
wherein said voltage control device operates in a low impedance state or a high impedance state according to the terminal voltage difference between said first end and second end of at least one said light emitting element;
wherein said voltage control device operates in a high impedance state when said voltage difference is between zero and a first breakover voltage, and operates in a low impedance state when said terminal voltage difference reaches or exceeds said first breakover voltage;wherein said voltage control device conducts negligible amount of current in said high impedance state compared to the current in said light emitting element; wherein said voltage control device provides at least a current path parallel to at least a said light emitting device when in its low impedance state. - View Dependent Claims (2, 3, 4, 5, 6, 7)
- each said light emitting element comprising a first end and a second end;
-
8. An apparatus comprising
a plurality of light emitting elements each comprising a first end and a second end; -
each of said light emitting element operating to emit light at or above a first onset voltage by conducting an electrical current; wherein said apparatus further comprises at least a voltage control devices;
wherein said voltage control device operates in a low impedance state or in a high impedance state according to the terminal voltage difference between the first end of a first said light emitting device and the first end of a second said light emitting device;wherein said voltage control device operates in a high impedance state when said terminal voltage difference is between zero and a first breakover voltage, and operates in a low impedance state when said terminal voltage reaches or exceeds said first breakover voltage; wherein said voltage control device conducts negligible amount of current in said high impedance state compared to the current in said light emitting element; wherein said voltage control device provides at least a current path across said two light emitting devices when in its low impedance state. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24)
-
-
25. A driving electronic circuit comprising:
-
a current source comprising a first terminal;
wherein said current source directs a current via said first terminal;a voltage adaptive circuit comprising a second and a third terminals; wherein when said third terminal is connected to a reference voltage and said first terminal and said second terminal connected to a load, said current is directed from said first terminal to said second terminal via said load; wherein said second terminal voltage varies between said reference voltage and said first terminal voltage according to the current. - View Dependent Claims (26, 27)
-
-
28. A three terminal device comprising, a light emitting device having a first end and a second end, a diac-like device, wherein one end of diac is connected to said first end of said light emitting device.
Specification