Knowledge Can RGB LEDs Produce White Light?

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Knowledge Can RGB LEDs Produce White Light?


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Yes, but it's rarely practical to produce white light using RGB LEDs. An RGB LED contains diodes capable of producing visible light of three primary colors of (red, green, and blue). Using these colors for additive color mixing can create any desired color inside the gamut of RGB color space where the whitest colors sit near the center. Color-mixed LEDs are theoretically the most efficient architecture because additive color mixing does not suffer from the energy loss associated with phosphor down-conversion (referred to as Stokes loss). In addition the narrow emission spectrum of monochromatic colors allows for a high luminous efficacy of radiation (LER). These, however, are only in theory.

In practice, the quantum efficiency of green LEDs is far below that of blue and red LEDs, leading to a white LED efficacy that is significantly lower than phosphor-converted LEDs. White light emitted by RGB LEDs has a poor color rendering because of the uneven spread of radiant power across the visible spectrum. The narrow full width at half maximum (FWHM) values of the green and red LEDs (in the range of from about 15 nm to about 30 nm) result in spectral gaps in the light spectrum. Another disadvantage is that the requirement for accurate dimming control of individual LED channels demands the use of complex electronics. This adds to the cost of using light sources.