LIGHT SOURCE WITH LIGHT SENSOR

• US 20100301755A1
• Filed: 06/01/2009
• Published: 12/02/2010
• Est. Priority Date: 06/01/2009
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Slack, Brandon Dean, Kerr, Duncan, Pance, Aleksandar, Bilbrey, Brett
• Granted Patent: US 9,247,611 B2
• Time in Patent Office: Days
• US Class Current: 315/149
• CPC Class Codes: H05B 45/22 using optical feedback
• 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

There are provided systems, devices and methods for operating a light source with a light sensor to provide a desired light output. In particular, in one embodiment, there is provided a light control system. The light control system includes a light source and a light sensor that share a common light pathway. Additionally, the light control system includes a controller electrically coupled to the light source and the light sensor. The controller operates the light source and the light sensor alternatively during a periodic cycle having a frequency of approximately 60 Hz or greater to achieve a desired visual effect based on ambient lighting conditions.

Claims

1. A light control system comprising:

a light source;

a light sensor configured to sense ambient light levels, wherein the light sensor and the light source share a common light pathway;

a controller communicatively coupled to the light source and the light sensor, wherein the controller operates the light source and the light sensor alternatively during a periodic cycle having a frequency greater than or equal to 60 Hz.

2. The light control system of claim 1 wherein the controller dynamically adjusts the output of the light source based on the determined ambient light level.

3. The light control system of claim 2 wherein the controller adjusts the brightness of the light source by reducing the length of time the light source is actuated.

4. The light control system of claim 3 wherein the controller adjusts the brightness of the light source to match the determined level of ambient light.

5. The light control system of claim 1 wherein the light source comprises top-firing LED.

6. The light control system of claim 1 wherein the light source is a side firing LED and the light sensor and light source are located in along different axes relative to a longitudinal axis of light pathway.

7. The light control system of claim 2 wherein the controller adjusts the brightness of the light source so that the surface of the light source appears painted in the sensed ambient light conditions.

8. The light control system of claim 1 wherein the light source comprises a multicolored LED.

9. The light control system of claim 1 wherein the light source comprises one or more LEDs and wherein the one or more LEDs function as the light sensor.

10. The light control system of claim 1 wherein the light sensor comprises one of a photodiode, a phototransistor, and photodiode and an amplifier.

11. The light control system of claim 1 wherein the light sensor comprises one or more narrowband photosensitive devices.

12. The light control system of claim 1 wherein the light sensor comprises a broadband photosensitive device.

13. The light control system of claim 1 comprising a master controller, wherein the master controller is configured to provide control signals to the controller.

14. The light control system of claim 1 wherein the light source and light sensor are component parts of a single package.

15. A method of operating a lighting system comprising:

providing a periodic control signal having a frequency equal to or exceeding 60 Hz;

actuating a light source during a first portion of the control signal;

actuating a light sensor during a second portion of the control signal to determine lighting conditions, the light source and the light sensor sharing a common light pathway; and

dynamically adjusting an output of the light source based on the determined lighting conditions.

16. The method of claim 15 comprising pulse width modulating the actuation of the light source during the first portion of the control signal to adjust the brightness of the light output by the light source.

17. The method of claim 15 wherein actuation of the light sensor generates an analog signal correlative to the amount of ambient light, the method comprising converting the analog signal to a digital signal for determination of the amount of ambient light and actuating the light source to correspond with the determined amount of ambient light.

18. The method of claim 15 comprising determining a color of the ambient light and actuating the light source to match the color of the ambient light.

19. A method of manufacture comprising:

measuring ambient light conditions;

adjusting a light output by one or more light sources to provide a desired visual effect for the corresponding measured ambient light conditions;

recording the measured ambient light conditions and the corresponding adjusted light output; and

programming a device to;

determine ambient light conditions; and

actuate the light sources to provide a light output that corresponds to the determined ambient light conditions based on the recorded data.

20. The method of claim 19 wherein adjusting the light output comprises pulse width modulating the one or more light sources to obtain a desired color and brightness output that corresponds to the ambient light conditions.