CPC G01J 1/0252 (2013.01) [G01J 1/32 (2013.01); G01J 3/0286 (2013.01); G01J 3/465 (2013.01); G01J 3/502 (2013.01); G01J 3/505 (2013.01); H05B 45/20 (2020.01); H05B 45/46 (2020.01); H05B 47/19 (2020.01); G01J 2001/4252 (2013.01); G01J 2001/444 (2013.01); H05B 47/195 (2020.01)] | 20 Claims |
1. An illumination device, comprising:
a substrate having a first surface and a second surface transversely opposed to first surface across a thickness of substrate, wherein the substrate includes material having a first thermal conductivity;
a light-emitting diode (LED) array disposed on the first side of substrate, the LED array including a plurality of LEDs, each of the plurality of LEDs having a different emission spectrum;
at least one photodetector disposed proximate the LED array on the first side of the substrate;
a thermally transmissive layer disposed on the second side of substrate, the thermally transmissive layer including a material having a second thermal conductivity greater than the first thermal conductivity;
a plurality of thermally conductive pathways thermally conductively coupling each of the plurality of LEDs to the thermally transmissive layer—each of the thermally conductive pathways including a material having a third thermal conductivity greater than the first thermal conductivity; and
control circuitry coupled to the plurality of LEDs, the control circuitry to:
for each of the plurality of LEDs, at each of a plurality of ambient temperatures:
apply a plurality of different level drive currents to the respective LED while applying a non-operative drive current to the remaining plurality of LEDs;
measure a luminous output of the respective LED using the at least one photodetector; and
generate a luminous output curve as a function of drive current.
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