Patent attributes
A lighting apparatus includes a combination of LED dice that emit light of a first color and a wavelength-shifting material (e.g., phosphor) that converts light of the first color to light of a second color. An appropriate combination of light of the first color and light of the second color can be used to produce light of a target color. In an embodiment, LED dice in the lighting apparatus are divided into two groups. Each LED die in the first group is combined with less wavelength-shifting material than needed to produce light of the target color, while each LED die in the second group is combined with more wavelength-shifting material than needed to produce light of the target color. As a result, the two groups produce light having colors on opposite sides of the target color in the International Commission on Illumination (CIE) chromaticity diagram. In some embodiments, the target color and color variations of both groups are on one straight line in the CIE chromaticity diagram, although it is to be understood that there might be small scattering within the groups. By adjusting the relative brightness of the two groups, the target color can be obtained.
