Hybrid gas discharge lamp-LED lighting system

• US 8,102,127 B2
• Filed: 06/24/2007
• Issued: 01/24/2012
• Est. Priority Date: 06/24/2007
• Status: Expired due to Fees

• Current Assignee: Philips Lighting BV (Koninklijke Philips N.V.)
• Original Assignee: Cirrus Logic Incorporated
• Inventors: Melanson, John L.
• Primary Examiner(s): TRAN, THUY V
• Application Number:
  US11/767,523
• Publication Number:
  US 20080315791A1
• Time in Patent Office: 1,675 Days
• Field of Search: 315/178, 315/246, 315/247, 315/250, 315/291, 315/307, 315/312, 315/324, 315/360
• US Class Current: 315/178
• CPC Class Codes: F21Y 2113/00 Combination of light sources
• CPC Class Codes: F21Y 2113/20 of different form
• CPC Class Codes: H05B 35/00 Electric light sources using a combination of different types of light generation

Abstract

A lighting system and method combine at least one LED and at least one gas discharge lamp within a common housing. The lighting system includes a control system to dependently operate each LED and each gas discharge lamp during overlapping, non-identical periods of time. In at least one embodiment, the control system can provide light output by activating LEDs during gas discharge preheating operations and thus extend the useful life of each gas discharge lamp. When dimming the lighting system, the control system can reduce current to the gas discharge lamps and one or more gas discharge lamps can be phased out as dimming levels decrease. As dimming levels decrease, one or more of the LEDs can be activated or groups of LEDs can be phased in to replace the light output of the dimmed gas discharge lamps. Thus, the lighting system can reduce power consumption at low dimming levels.

Claims

1. A hybrid gas discharge lamp-light emitting diode (LED) lighting system comprising:

a housing;

an LED retained by the housing;

multiple gas discharge lamps retained by the housing; and

a control system coupled to the LED and the gas discharge lamps to dependently operate the LED and at least one of the gas discharge lamps during overlapping, non-identical periods of time, wherein the control system is further configured to (i) coordinate current level adjustment to the LED and the gas discharge lamps to dim the lighting system, (ii) dim the LED and each gas discharge lamp to a first light output level, and (iii) further dim only a subset of the gas discharge lamps to a second light output level, wherein the first light output level is greater than the second light output level.

2. The lighting system of claim 1 wherein the control system is further configured to (i) preheat filaments of the gas discharge lamp for a first period of time prior to causing an arc within the gas discharge lamp, (ii) activate the LED during the first period of time, and (iii) cause an arc within at least one of the gas discharge lamps during a second period of time.

3. The lighting system of claim 2 wherein the control system is further configured to deactivate the LED during at least a portion of the second period of time.

4. The lighting system of claim 1 further comprising:

multiple LEDs retained by the housing; and

wherein the control system is further configured to (i) dim each LED and each gas discharge lamp to a first light output level and (ii) further dim only a subset of the gas discharge lamps to a second light output level, wherein the first light output level is greater than the second light output level.

5. The lighting system of claim 1 wherein the second light output level is zero.

6. The lighting system of claim 1 wherein the subset is a proper subset.

7. The lighting system of claim 1 further comprising:

multiple LEDs retained by the housing;

wherein the control system is further configured to decrease current to each gas discharge lamp and increase current to each LED.

8. The lighting system of claim 7 wherein the control system is further configured to decrease current to each gas discharge lamp and, with no more than an insubstantial delay, increase current to each LED and the insubstantial delay is no more than 3 seconds.

9. The lighting system of claim 1 wherein at least one of the gas discharge lamps includes a gas chamber to contain a gas and the LED is contained within the gas chamber.

10. The lighting system of claim 1 wherein at least one of the gas discharge lamps and the LED are coupled separately to the housing.

11. The lighting system of claim 1 wherein at least one of the gas discharge lamps is a fluorescent lamp.

12. The lighting system of claim 1 further comprising:

a power factor correction circuit; and

a light source driver coupled to the LED, the gas discharge lamps, the power factor correction circuit, and the control system.

13. A lighting system control system to control a hybrid gas discharge lamp-light emitting diode (LED) lighting system, the control system comprising:

a first output to provide an LED control signal;

a second output to provide a gas discharge lamp control signal;

circuitry to dependently operate at least one LED and multiple gas discharge lamps during overlapping, non-identical periods of time; and

an input to receive a dimming signal, wherein the circuitry is further configured to respond to the dimming signal and (i) dim each LED and each gas discharge lamp to a first light output level and (ii) further dim only a subset of the gas discharge lamps to a second light output level, wherein the first light output level is greater than the second light output level.

14. The control system of claim 13 wherein the control system is further configured to (i) warm filaments of the gas discharge lamp for a first period of time prior to causing an arc within the gas discharge lamp, (ii) activate the LED during the first period of time, and (iii) cause an arc within the gas discharge lamp during a second period of time.

15. The control system of claim 14 wherein the control system is further configured to deactivate the LED during at least a portion of the second period of time.

16. The control system of claim 13 further comprising:

an input to receive a dimming signal, wherein the control system is further configured to coordinate current level adjustment to the LED and the gas discharge lamp to dim the lighting system in accordance with the dimming signal.

17. A method of controlling a hybrid gas discharge lamp-light emitting diode (LED), the method comprising:

supplying a control signal to a control system configured to control operation of an LED and gas discharge lamps retained by a housing;

operating the LED and at least one of the gas discharge lamps dependently during overlapping, non-identical periods of time;

coordinating current level adjustment to the LED and the gas discharge lamps to dim the lighting system;

dimming the LED and each gas discharge lamp to a first light output level; and

further dimming only a subset of the gas discharge lamps to a second light output level, wherein the first light output level is greater than the second light output level.

18. The method of claim 17 further comprising:

preheating filaments of at least one of the gas discharge lamps for a first period of time prior to causing an arc within at least one of the gas discharge lamps;

activating the LED during the first period of time; and

causing an arc within at least one of the gas discharge lamps during a second period of time.

19. The method of claim 18 further comprising:

deactivating the LED during at least a portion of the second period of time.

20. The method of claim 17 further comprising:

coordinating current level adjustment to the LED and at least one of the gas discharge lamps to dim the lighting system.

21. The method of claim 20 wherein the housing further retains multiple LEDs, the method further comprising:

dimming each LED and each gas discharge lamp to the first light output level.

22. The method of claim 20 wherein the housing further retains multiple LEDs and multiple gas discharge lamps, the method further comprising:

decreasing current to each gas discharge lamp and increasing current to each LED.

23. The method of claim 22 further comprising:

decreasing current to each gas discharge lamp and, with no more than an insubstantial delay, increase current to each LED wherein the insubstantial delay is no more than 3 seconds.

24. A hybrid gas discharge lamp-light emitting diode (LED) lighting system comprising:

a housing;

an LED retained by the housing;

a gas discharge lamp retained by the housing; and

a control system coupled to the LED and the gas discharge lamp to dependently operate the LED and gas discharge lamp during overlapping, non-identical periods of time, wherein the control system is further configured to (i) preheat filaments of the gas discharge lamp for a first period of time prior to causing an arc within the gas discharge lamp, (ii) activate the LED during the first period of time, and (iii) cause an arc within the gas discharge lamp during a second period of time.

25. The lighting system of claim 24 wherein the control system is further configured to deactivate the LED during at least a portion of the second period of time.

26. A lighting system control system to control a hybrid gas discharge lamp-light emitting diode (LED) lighting system, the control system comprising:

a first output to provide an LED control signal;

a second output to provide a gas discharge lamp control signal; and

circuitry to dependently operate at least one LED and at least one gas discharge lamp during overlapping, non-identical periods of time, wherein the circuitry is further configured to (i) warm filaments of the gas discharge lamp for a first period of time prior to causing an arc within the gas discharge lamp, (ii) activate the LED during the first period of time, and (iii) cause an arc within the gas discharge lamp during a second period of time.

27. The control system of claim 26 wherein the circuitry is further configured to deactivate the LED during at least a portion of the second period of time.

28. A method of controlling a hybrid gas discharge lamp-light emitting diode (LED), the method comprising:

supplying a control signal to a control system configured to control operation of an LED and a gas discharge lamp retained by a housing;

operating the LED and gas discharge lamp dependently during overlapping, non-identical periods of time;

preheating filaments of the gas discharge lamp for a first period of time prior to causing an arc within the gas discharge lamp;

activating the LED during the first period of time; and

causing an arc within the gas discharge lamp during a second period of time.

29. The method of claim 28 further comprising:

deactivating the LED during at least a portion of the second period of time.

30. A method of controlling a hybrid gas discharge lamp-light emitting diode (LED), wherein a housing retains multiple LEDs and multiple gas discharge lamps, the method comprising:

supplying a control signal to a control system configured to control operation of at least one of the LEDs and at least one of the gas discharge lamps retained by a housing;

operating the LED and at least one of the gas discharge lamps dependently during overlapping, non-identical periods of time;

coordinating current level adjustment to the LED and at least one of the gas discharge lamps to dim the lighting system; and

decreasing current to each gas discharge lamp and, with no more than an insubstantial delay, increasing current to each LED wherein the insubstantial delay is no more than 3 seconds.