Abstract: Techniques are described to allow a low-cost light fixture to produce light with a relatively high color rendering index (CRI) across a range of color temperatures. A rectified AC voltage may be provided to multiple groups of light-emitting diodes (LEDs) having characteristics related to a range of color temperatures and a target CRI level. The multiple groups of LEDs may be controlled based on a received control signal, such that the combined groups of LEDs produce combined light having a produced color temperature within the range of color temperatures, and having a produced CRI level that is approximately the target CRI level. In some implementations, the received control signal is modified by a modification circuit, and the multiple groups of LEDs may be controlled based on the modified control signal.
Type:
Grant
Filed:
December 9, 2016
Date of Patent:
December 12, 2017
Assignee:
ALB IP HOLDING LLC
Inventors:
Towfiq Chowdhury, Michael Z. Gielniewski, Feng Chen, Alejandro Lopez