An optically addressable display includes a plurality of receptor and
emitter pairs where each pair is for receiving optical display
information and for generating light indicative of the display
information. Each individual receptor and emitter pair is coupled
electrically by an associated control circuit that facilitates driving
the emitter so it generates either the received display information or
annotation information generated by a light wand that is capable of being
optically coupled to individual ones of the plurality of receptors. Each
control circuit has a pulse density capture circuit that receives a pulse
train signal indicative of a desired brightness or hue levels and drives
an individual one of the emitters on and off at a determined duty cycle
to produce the desired brightness or hue levels. In another embodiment
sets of receptor and emitter pairs are grouped in cells, where each cell
is capable of generating N of shades of different colors.