LED EMULATION OF INCANDESCENT BULB BRIGHTNESS AND COLOR RESPONSE TO VARYING POWER INPUT AND DIMMER CIRCUIT THEREFOR

• US 20110031890A1
• Filed: 10/18/2010
• Published: 02/10/2011
• Est. Priority Date: 05/28/2009
• Status: Active Grant

• Current Assignee: Thomas E. Stack
• Original Assignee: Thomas E. Stack
• Inventors: Stack, Thomas E.
• Granted Patent: US 8,890,419 B2
• Time in Patent Office: Days
• US Class Current: 315/228
• CPC Class Codes: H05B 31/50 specially adapted for ac
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/42 Antiparallel configurations
• CPC Class Codes: H05B 45/50 responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits
• CPC Class Codes: H05B 47/24 Circuit arrangements for protecting against overvoltage

Abstract

A lighting system is disclosed. The lighting system includes a first lighting module and a second lighting module connected parallel to the first lighting module. The first lighting module generates light at a first color temperature and the second lighting module generates light at a second color temperature. The first lighting module has a first activation voltage and the second lighting module has a second activation voltage. The two lighting modules generate light when the current flow through them. When input voltage is changed, not only does the amount of current flowing through the two modules change, but also ratio of the amount of current flowing through the two lighting modules changes. The change in the ratio changes the color temperature of the light produced by the lighting system which is a combination of the light produced by the two modules.

Claims

1. A lighting system comprising:

a first lighting module including at least one light emitting element, the light emitting element of said first lighting module generating, when power is applied, light at a first color temperature;

wherein said first lighting module having a first activation voltage;

a second lighting module including at least one light emitting element, the light emitting element of said second lighting module generating, when power is applied, light at a second color temperature; and

wherein said second lighting module having a second activation voltage.

2. The lighting system recited in claim 1 wherein said first lighting module including at least one pair of lighting elements, each pair including a first lighting element connected in a first electrical direction and a second lighting element connected in a second electrical direction, the second electrical direction opposite the first electrical direction.

3. The lighting system recited in claim 2 wherein the lighting elements are light emitting diodes.

4. The lighting system recited in claim 1 wherein said second lighting module is electrically connected in parallel to said first lighting module.

5. The lighting system recited in claim 1 further comprising:

a first capacitor connected in series with said first lighting module, said first capacitor connected in parallel to said second lighting module;

a second capacitor connected in series with both said first lighting module and said second lighting module;

wherein, said second lighting module is electrically connected in parallel to said first lighting module; and

wherein, when electrical power is applied to the lighting system, said first lighting module conducts electrical current during a first conduction period within each power cycle and said second lighting module conducts electrical current during a second conduction period within each power cycle.

6. The lighting system recited in claim 5 wherein the second conduction period occurs within the first conduction period.

7. The lighting system recited in claim 5 wherein a portion of the first conduction period overlaps a portion of the second conduction period.

8. The lighting system recited in claim 1 further comprising:

a first rectifier connected to said first lighting module;

a second rectifier connected to said second lighting module;

a third capacitor connected in parallel to said first lighting module;

a fourth capacitor connected in parallel to said second lighting module;

wherein said first lighting module comprises a plurality of light emitting elements connected in series; and

wherein said second lighting module comprises a plurality of light emitting elements connected in series.

9. The lighting system recited in claim 1 further comprising supporting circuit, said supporting circuit comprising at least one from a group consisting of a thermistor, a spark gap, and a transient voltage suppressor.

10. The lighting system recited in claim 1 wherein said first lighting module includes a first predetermined number of LEDs and said second lighting module includes a second predetermined number of LEDs wherein the first predetermined number is less than the second predetermined number.

11. A method of generating light, the method comprising:

applying electrical energy;

activating a first lighting module at a first activation voltage;

activating a second lighting module at a second activation voltage;

wherein the first lighting module including at least one light emitting element, the light emitting element of the first lighting module, when activated, generating light at a first range of color temperature; and

wherein the second lighting module including at least one light emitting element, the light emitting element of the second lighting module, when activated, generating light at a second range of color temperature.

12. The method recited in claim 11 wherein said first lighting module includes at least one pair of lighting elements, each pair including a first lighting element connected in a first electrical direction and a second lighting element connected in a second electrical direction, the second electrical direction opposite the first electrical direction.

13. The method recited in claim 12 wherein the lighting elements are light emitting diodes.

14. The method recited in claim 11 wherein said second lighting module is electrically connected in parallel to said first lighting module.

15. The method recited in claim 11 wherein the first lighting module conducts electrical current during a first conduction period within each power cycle and the second lighting module conducts electrical current during a second conduction period within each power cycle.

16. The method recited in claim 15 wherein the second conduction period occurs within the first conduction period.

17. The method recited in claim 15 wherein a portion of the first conduction period overlaps a portion of the second conduction period.

18. A lighting system adapted to connect to an electrical power source providing alternating current (AC) electrical power, the electrical power having power cycles and adapted to provide variable level of voltage, the lighting system comprising:

a first current path including at least one light emitting element, the light emitting element of said first current path generating, when power is applied, light at a first color temperature;

wherein said first current path has a first activation voltage;

a second current path including at least one light emitting element, the light emitting element of said second current path generating, when power is applied, light at a second color temperature; and

wherein said second current path has a second activation voltage.