LED luminaire with improved life and operation management

• US 8,111,011 B1
• Filed: 01/10/2008
• Issued: 02/07/2012
• Est. Priority Date: 01/11/2007
• Status: Expired due to Fees

• Current Assignee: Leotek Electronics Corp (Lite-On Technology Corporation)
• Original Assignee: Leotek Electronics Corp (Lite-On Technology Corporation)
• Inventors: Tu, Chin-Wang, Wu, Chen-Ho, Wang, Shih Chang
• Primary Examiner(s): Le, Tung X
• Application Number:
  US11/972,561
• Time in Patent Office: 1,489 Days
• Field of Search: 315/117, 315/149, 315/291, 315/297, 315307-309, 315/312, 315/360
• US Class Current: 315/307
• CPC Class Codes: H05B 45/20 Controlling the colour of the light

Abstract

A method and apparatus for adjusting the drive signal of an LED luminaire is provided and includes an LED light source assembly, an ambient sensor circuit, a comparator circuit, and a driver circuit. The ambient sensor circuit provides an ambient signal to the LED light source assembly, which is a function of the ambient (such as temperature, humidity or air visibility) proximate to the LED light source assembly. The comparator circuit provides a bidirectional ambient adjustment signal to the driver circuit, which is a function of the ambient signal and a reference signal. And the driver circuit provides an adjustable drive signal to the LED light source assembly, which is a function of the bidirectional ambient adjustment signal.

Claims

1. An LED luminaire apparatus, comprising:

an LED light source assembly for producing an optical output;

a humidity sensor circuit coupled to the LED light source assembly, wherein the humidity sensor circuit provides a humidity signal, and wherein the humidity signal is a function of humidity proximate to the LED light source assembly; and

a driver circuit coupled to the LED light source assembly, wherein the driver circuit provides an adjustable drive signal to the LED light source assembly that dictates a yellow color content of the optical output generated by the LED light source assembly, and wherein the driver circuit is configured to adjust the drive signal to increase the yellow color content as the humidity proximate the LED light source assembly increases, and to decrease the yellow color content as the humidity proximate the LED light source decreases; and

a comparator circuit coupled to the humidity sensor circuit and the driver circuit, wherein the comparator circuit provides a bidirectional amber adjustment signal which is a function of a comparison between the humidity signal and a reference signal of known value, and wherein the bidirectional amber adjustment signal is received by the driver circuit.

2. The apparatus of claim 1 further comprising:

a time counter circuit for monitoring the adjustable drive signal so as to provide a temporal signal that is a function of a total length of time the adjustable drive signal has been provided to the LED light source assembly.

3. The apparatus of claim 1, wherein the LED light source assembly comprises a plurality of red, green, and blue LEDs, and wherein a combination of red, green and blue intensities therefrom forms the optical output and is adjusted in response to changes in the drive signal to increase and decrease the yellow content thereof.

4. The apparatus of claim 3 further comprising:

an RGB controller, wherein the adjustable drive signal is routed to the plurality of red, green, and blue LEDS via the RGB controller.

5. The apparatus of claim 1, wherein the LED light source assembly comprises a plurality of amber LEDs for providing an increased yellow color in the optical output in response to the drive signal as the humidity proximate the LED light source assembly increases, and a decreased yellow color in the optical output in response to the drive signal as the humidity proximate the LED light source decreases.

6. A method of managing a drive signal to an LED luminaire, comprising:

sensing humidity proximate to an LED light source assembly using a humidity sensor circuit;

generating a humidity signal that is a function of the sensed humidity proximate to the LED light source assembly using a comparator circuit that provides a bidirectional amber adjustment signal which is a function of a comparison between the humidity signal and a reference signal of known value;

generating an adjustable drive signal that dictates a yellow color content of an optical output of the LED light source assembly; and

adjusting the drive signal in response to changes in the humidity signal to increase the yellow color content as the humidity proximate the LED light source assembly increases, and to decrease the yellow color content as the humidity proximate the LED light source decreases.

7. The method of claim 6, wherein the LED light source assembly comprises a plurality of red, green, and blue LEDs, and wherein the increasing and decreasing of the adjustable drive signal changes the yellow color content of the optical output from the LED light source assembly.

8. The method of claim 6, wherein the LED light source assembly comprises a plurality of amber LEDs, and wherein the increasing and decreasing of the adjustable drive signal changes the luminosity of the amber LEDs.