Brightness Controlled Light Source

• US 20090309500A1
• Filed: 06/12/2008
• Published: 12/17/2009
• Est. Priority Date: 06/12/2008
• Status: Active Grant

• Current Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Original Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Inventors: Reisch, Juergen
• Granted Patent: US 8,212,483 B2
• Time in Patent Office: Days
• US Class Current: 315/158
• CPC Class Codes: B60Q 1/1423 Automatic dimming circuits, i.e. switching between high beam and low beam due to change of ambient light or light level in road traffic
• CPC Class Codes: H05B 47/11 by determining the brightness or colour temperature of ambient light
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection

Abstract

A method and system is provided for automatic brightness control of a light source. The system includes at least one light sensor that operates in a different range of the light spectrum than the light spectrum generated by the controlled light source.

Claims

1. A light control system for controlling a light source that generates light in a first range of the light spectrum, the system comprising:

a light sensor that operates in a second range of the light spectrum, the second range different than the first range; and

control logic coupled to the light sensor, the light sensor providing information to the control logic to control a brightness of the light source.

2. The system according to claim 1, wherein the second range of the light spectrum is substantially non-overlapping with the first range of the light spectrum.

3. The system according to claim 1, wherein the light sensor provides information to control the brightness of the light source as a function of daylight intensity sensed by the light sensor.

4. The system according to claim 1, wherein the light sensor operates in the ultraviolet range of light spectrum such that the controlled brightness of the light source depends substantially on daylight incidence or on sunlight in the vicinity of the light source.

5. The system according to claim 1, wherein the light sensor causes the light intensity of the light source to be regulated within a range from 0 to maximum and/or from the switched off status of the controlled light source to the maximum light emission of the light source.

6. The system according to claim 1, wherein the light sensor comprises an opto-electronic sensor.

7. The system according to claim 1, wherein the light sensor detects an ultraviolet portion of the light spectrum, the light sensor comprising active electronic elements that amplify a current generated in the light sensor.

8. The system according to claim 1, wherein the light sensor comprises an electronic wavelength filter that electronically selects the ultraviolet portion of the light spectrum.

9. The system according to claim 1, wherein the light control system comprises a programmable brightness control system.

10. The system according to claim 9, wherein the programmable brightness control system is programmable to regulate the brightness of the light source as a function of ambient brightness of light in the second range in the vicinity of the controlled light source.

11. The system according to claim 1, wherein the light sensor and the control logic are implemented in a single integrated circuit.

12. The system according to claim 1, wherein the integrated circuit includes functionality implemented in CoolMos technology.

13. The system according to claim 11, wherein the integrated circuit is integrated in the light source, in a socket of the light source, in a casing of the light source and/or in a glass bulb of the light source.

14. The system according to claim 1, further comprising the light source, the light source coupled to the control logic.

15. The system according to claim 14, further comprising an AC/DC rectifier or transformer, a control logic and/or a voltage converter coupled between the light sensor and the light source.

16. The system according to claim 14, further comprising an insulated gate bipolar transistor element for controlling or regulating current in a proportionate manner to the light power to be emitted from the light source, the insulated gate bipolar transistor element being coupled between the light sensor and the light source.

17. The system according to claim 14, wherein a current supply for the light control system is provided by an interface parallel or coupled to a socket connection of the light source.

18. The system according to claim 14, wherein the light control system is capable of implementing a power-saving mode and/or a low standby current mode.

19. The system according to claim 14, wherein the light sensor is arranged with an orientation to ambient light such that the light sensor substantially detects brightness of natural light in the vicinity of the light source as a basis for the regulation of the brightness of the controlled light source.

20. The system according to claim 14, wherein the light source comprises a bulb, a light emitting diode, a fluorescent lamp, a quartz lamp, a low-energy light bulb or a dimmable energy saving lamp.

21. The system according to claim 14, wherein the light source comprises a car headlight.

22. The system according to claim 14, wherein the light source comprises a plurality of light sources.

23. A method for automatic brightness control of a light source, the method comprising:

detecting brightness or intensity of light near a controlled light source by means of at least one light sensor that operates in a different range of the light spectrum than the light spectrum generated by the controlled light source; and

regulating the brightness of the controlled light source based on the detected brightness or intensity of light detected near the controlled light source.

24. The method according to claim 23, wherein detecting brightness or intensity near the controlled light source is performed by means of at least one light sensor that is substantially insensitive to light generated by the controlled light source.

25. The method according to claim 23, wherein the brightness or intensity of the controlled light source is regulated substantially dependent on daylight incidence or on sunlight in the vicinity of the controlled light source.

26. The method according to claim 23, wherein invisible light in the ultraviolet range of the light spectrum is detected by the at least one light sensor and utilized to regulate the brightness of the controlled light source.

27. The method according to claim 23, wherein regulating the brightness comprises varying light intensity of the controlled light source within a range from 0 to maximum and/or from a switched off status of the controlled light source to a maximum light emission power of the controlled light source.

28. The method according to claim 23, wherein the brightness generated by the controlled light source is regulated substantially independent of self-generated ambient brightness and/or room brightness and independent of light generated by artificial light sources.

29. The method according to claim 23, wherein the light sensor operates in the range of 200 nm to 500 nm wavelength.

30. The method according to claim 23, wherein the brightness of the controlled light source is regulated on a linearly and/or on a logarithmically basis.

31. The method according to claim 23, wherein, the controlled light source requires alternating current and wherein opto-electronical sampling of the light sensor being performed during a voltage zero-crossing of the current supply to the controlled light source.

32. An integrated circuit comprising components of a control and/or regulatory system, the integrated circuit being arranged and adapted such that it can be used as a control and/or regulatory device for performing the method according to claim 23.