Patent ID: 7229202

Claim:
An illumination apparatus for a surgical microscope, the illumination apparatus comprising: an LED arrangement including a plurality of light-emitting diodes (LEDs) each emitting non-white light; a multi-arm light guide located after the LED arrangement, the multi-arm light guide including a coupler defining a single light exit end, wherein the multi-arm light guide includes one light guide arm associated with each of the plurality of LEDs, each of the light guide arms having a light-accepting end arranged to receive light from the associated LED, whereby light leaving the light guide through the light exit end is mixed to provide white illuminating light for the surgical microscope; a plurality of filters arranged one between each of the light guide arms and the LED associated therewith; a light-sensitive measurement sensor; at least one additional light guide arm arranged to direct light from the coupler to the measurement sensor, wherein the light from the coupler includes light reflected from an observed specimen; and a signal processing unit connected to the measurement sensor and to the plurality of LEDs and the plurality of filters, wherein the intensity and spectral composition of the light of the individual light-emitting diodes and the filters, are controlled by the signal processing unit.