Illumination system having at least two light sources, and a method for operating such an illumination system

• US 7,288,900 B2
• Filed: 09/06/2005
• Issued: 10/30/2007
• Est. Priority Date: 09/20/2004
• Status: Expired due to Fees

• Current Assignee: Patent-Treuhand-Gesellschaft Fur Elektrische Gluhlampen mbH (Ams-Osram AG)
• Original Assignee: Patent-Treuhand-Gesellschaft Fur Elektrische Gluhlampen mbH (Ams-Osram AG)
• Inventors: Hirschmann, Gunther, Hackenbuchner, Stefan, Biebl, Alois, Weitzel, Reinhard
• Primary Examiner(s): Owens; Douglas W.
• Assistant Examiner(s): VU, JIMMY T
• Application Number:
  US11/218,624
• Publication Number:
  US 20060061300A1
• Time in Patent Office: 784 Days
• Field of Search: 315/224, 315/291, 315/307, 315/312, 315/360, 315/225, 315/293, 315/294
• US Class Current: 315/291
• CPC Class Codes: H05B 35/00 Electric light sources using a combination of different types of light generation
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/22 using optical feedback

Abstract

An illumination system has at least two light sources of which at least one light source includes an LED, and a driver device designed to operate at least the one LED with a DC signal; a sensor device for determining at least one feature of the light output; an actual value storage device connected to the sensor device for storing an actual value of the feature; a setpoint selection device for storing a setpoint of the feature; and a control device connected on the input side to the actual value storage device for of transmitting the actual value, and to the setpoint selection device for transmitting the setpoint, and which provides the driver device with a control signal that changes a characteristic of the DC signal used for driving the LED such that the actual value approaches the setpoint.

Claims

1. An illumination system having at least two light sources of which at least one light source comprises an LED (11), characterized in that it furthermore comprises:

a driver device (22) that is designed to operate at least the one LED (11) with a DC signal;

a sensor device (12) with the aid of which at least one feature of the light output by the illumination system can be determined;

an actual value storage device (14) that is connected to the sensor device (12) and in which an actual value of the at least one feature can be stored;

a setpoint selection device (18) in which a setpoint of the at least one feature can be stored; and

a control device (16) that is connected on the input side to the actual value storage device for the purpose of transmitting the actual value of the at least one feature, and to the setpoint selection device (18) for the purpose of transmitting the setpoint of the at least one feature, and which is designed to provide the driver device (22) at its output with a control signal in such a way that the driver device changes a characteristic of the DC signal used for driving the at least one LED (11) in such a way that the actual value approaches the setpoint.

2. The illumination system as claimed in claim 1, characterized in that the characteristic of the DC signal is its amplitude.

3. The illumination system as claimed in claim 1, characterized in that the sensor device (12) comprises at least one voltage frequency converter (26).

4. The illumination system as claimed in claim 3, characterized in that the at least one voltage frequency converter (26) is connected to at least one filter device (24) for the purpose of determining the actual value of the at least one feature of the light output by the illumination system.

5. The illumination system as claimed in claim 3, characterized in that the sensor device (12) comprises a microprocessor that is connected to the output of the at least one voltage frequency converter (26), in particular for the purpose of counting the pulses in the output signal of the at least one voltage frequency converter (26).

6. The illumination system as claimed in claim 1, characterized in that, in addition to the at least one light source that comprises at least one LED (11), at least one further light source is present that is of the following type:

LED;

fluorescent lamp;

halogen incandescent lamp;

high pressure discharge lamp.

7. The illumination system as claimed in claim 1, characterized in that the features of the light output by the illumination system is the color temperature and/or the brightness and/or the color locus.

8. The illumination system as claimed in claim 1, characterized in that the illumination system comprises at least two LEDs that output light of different color.

9. The illumination system as claimed in claim 1, characterized in that the setpoint selection device (18) has an interface (20) into which at least one setpoint can be input by an operator, or at least one setpoint can be selected from a number of setpoints already stored in the setpoint selection device (18).

10. The illumination system as claimed in claim 1, characterized in that the driver device (22) is designed to operate all the light sources of the illumination system.

11. The illumination system as claimed in claim 10, characterized in that parameters for operating the light sources are stored in the driver device (22) for the case in which the sensor device (12) and/or the actual value storage device (14) and/or the setpoint selection device (18) fails.

12. The illumination system as claimed in claim 1, characterized in that the components of the illumination system are designed for operating in a motor vehicle, in particular the supply voltage required for operating the components, the quality of the light output by the illumination system.

13. The illumination system as claimed in claim 12, characterized in that one setpoint corresponds to a dimming position of the illumination system.

14. The illumination system in claim 2, characterized in that the sensor device (12) comprises at least one voltage frequency converter (26).