In publication 20110069511, we find a technique for separating LEDs based upon their white points, then ordering them during assembly such that the overall backlighting for the display produces a desirable average white point.
The end result? Apple can presumably maintain a tighter tolerance on overall display white point while accepting a lower tolerance on the individual LED backlights. The looser tolerance would likely lower the cost of the component LEDs.
1. An LED backlight method for display systems comprising:
receiving a plurality of light emitting diodes categorized into a plurality of bins, wherein each bin references a separate range of white point colors; and
determining an optimal order for mounting the plurality of light emitting diodes at spatially distributed positions, the plurality of light emitting diodes comprising white point colors associated with separate bins,
wherein the optimal order of the plurality of light emitting diodes produces a light of a desired white point color when the light outputs of the plurality of light emitting diodes are mixed.