Color temperature adjustable, LED based, white light source

摘要

Assemblies of temperature monitored, semiconductor light emitting diodes (LEDs) are disclosed that produce color temperature adjustable white light sources. Warm-white LEDs are combined with green and blue LEDs to produce light have continuous spectrum spanning the wavelength range of 400 to 700 nm with a white light point located at a selectable Planckian locus location and a color rendering index greater than 80. The circuitry includes LED temperature monitoring used to adjust LEDs spectral and luminosity output. Alternate arrangements combine warm-white LEDs with green, blue and red LEDs; warm-white and cool-white LEDs with green, blue and red LEDs; warm-white and cool-white LEDs with green LEDs; and a warm-white and cool-white LEDs with green-white LEDs.