Calibrated LED light module
First Claim
1. A light source comprising:
- a substrate;
a plurality of LEDs mounted on said substrate and encapsulated in a transparent cap, each LED emitting light having a different spectrum from said other LEDs, each LED generating light of an average intensity that is determined by a drive signal connected to that LED;
a sensor that generates a plurality of signals, each signal being characterized by a sensor value that is indicative of the intensity of light emitted by a corresponding one of said LEDs and independent of the intensity of light emitted by any other LED in said light source, said sensor comprising at least one photodetector that is encapsulated in said transparent cap; and
a controller that generates said drive signals and stores a current target value for each LED, wherein said light source operates in a calibration phase and an operation phase, wherein during said operation phase said controller generates said drive signals for each of said LEDs such that said sensor value for that LED matches said stored current target value for that LED, and wherein during said calibration phase, said controller stores said current target values.
6 Assignments
0 Petitions
Accused Products
Abstract
A light source and method for making the same are disclosed. The light source includes a plurality of LEDs mounted on a substrate and a sensor for measuring light from the LEDs. Each LED emits light having a different spectrum from the other LEDs, the average intensity of light from that LED being determined by a drive signal coupled to that LED. The sensor generates a plurality of signals, each signal being characterized by a sensor value that is proportional to the intensity of light emitted by a corresponding one of the LEDs. A controller generates the drive signals and stores a current target value for each LED. The drive signals for each of the LEDs is generated such that the sensor value for that LED matches the stored current target value for that LED.
-
Citations
10 Claims
-
1. A light source comprising:
-
a substrate;
a plurality of LEDs mounted on said substrate and encapsulated in a transparent cap, each LED emitting light having a different spectrum from said other LEDs, each LED generating light of an average intensity that is determined by a drive signal connected to that LED;
a sensor that generates a plurality of signals, each signal being characterized by a sensor value that is indicative of the intensity of light emitted by a corresponding one of said LEDs and independent of the intensity of light emitted by any other LED in said light source, said sensor comprising at least one photodetector that is encapsulated in said transparent cap; and
a controller that generates said drive signals and stores a current target value for each LED, wherein said light source operates in a calibration phase and an operation phase, wherein during said operation phase said controller generates said drive signals for each of said LEDs such that said sensor value for that LED matches said stored current target value for that LED, and wherein during said calibration phase, said controller stores said current target values. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A method for fabricating a light source, said method comprising:
-
attaching a plurality of LEDs to a substrate, each LED emitting light having a different spectrum from said other LEDs, each LED generating light of an average intensity that is determined by a drive signal connected to that LED; and
providing a sensor that generates a plurality of signals, each signal being characterized by a sensor value that is indicative of the intensity of light emitted by a corresponding one of said LEDs and independent of the intensity of light emitted by any other LED in said light source;
encapsulating said LEDs and said sensor in a transparent cap;
attaching a controller to said substrate, said controller being connected to said LEDs and said sensor, said controller generating said drive signals and storing a current target value for each LED wherein said light source operates in a calibration phase and an operation phase, wherein during said operation phase said controller generates said drive signals for each of said LEDs such that said sensor value for that LED matches said stored current target value for that LED, and wherein during said calibration phase, said controller stores said current target values;
causing said LEDs to generate light corresponding to a predetermined color point during said operation phase;
causing said controller to store said sensor values as said target values when said LEDs generate light of said predetermined color point during said calibration phase. - View Dependent Claims (9, 10)
-
Specification