A tunable white downlight is a spectrally adjustable luminaire that allows users to modulate the color temperature of white light. Tunable white lighting adds a new dimension to dynamic lighting. It is designed to optimize the spectral composition of white light such that the right amount of energy is emitted at the desired wavelengths of the visible spectrum. The spectral power distribution (SPD) of a light source determines its color characteristics which affect the color of light and color of objects.
The color appearance of white light is indicated by its color temperature or correlated color temperature (CCT) which is intended to characterize the color of light emitted by light sources other than incandescent radiators. This color metric system is designed to provide intuitive information about the perceptual effect of white light in the mind of the viewer. The lower the color temperature, the warmer the white light appears; the higher the color temperature, the cooler the white light appears. Whether the light is warm or cool in appearance is inherently dictated by its SPD. Warm white light is heavily laden with energy at red and orange wavelengths. Blue-enriched light appears cooler. Neutral white light has a balanced ratio between blue and red light in its spectrum.
at the Open Lighting Product Directory (OLPD)
