In one embodiment of an optical pointing device, an illumination system
includes a plurality of light sources. Each light source is characterized
by a unique set of illumination characteristics. Illumination
characteristics include impinging angle, light wavelength, light
homogeneity, and the like. A sensor receives electromagnetic energy
originating at the light source to scan an imaged area. The sensor
measures performance indexes associated with the light sources, which
depend on the illumination characteristics. The sensor includes an
imaging module, which may include passive filters, and control logic,
which includes at least a DSP module and a light sensor selection module.
Another embodiment includes additional signaling light sources that do
not interfere with the illumination system and are for signaling to the
user. A method to select the most adequate light source for any given
surface is based on measured performance indices.