Patent ID: 8520303

Claim:
A surgical microscope comprising: a viewing optic for enabling a viewer to view a magnified representation of a region of an object in a viewing area; said viewing optic defining a viewing beam path and including a continuously adjustable magnification system arranged in said viewing beam path; a viewing-optic adjusting unit assigned to said magnification system; an adjustable illuminating system for making illuminating light available for illuminating the object region in an adjustable illuminated area thereof with said illuminating light; said illuminating system including: a light source for supplying said illuminating light a unit for adjusting an illuminating luminous flux of said illuminating light from said light source; and, an optic component assembly for adjusting the size of said illuminated area; an illuminating-system control unit connected to said viewing-optic adjusting unit and being adapted to receive information as to the adjusted magnification of said viewing optic; said illuminating-system control unit being operatively connected to said illuminating system for adjusting said illuminating system to adapt the size of said illuminated area to the size of said viewing area; and, said illuminating-system control unit controlling said illuminating system in dependence upon the adjusted magnification of said viewing optic so as to adapt, in a first magnification range, wherein a transmission of said viewing optic is substantially constant, the size of said illuminated area in said object region while a constant irradiation intensity of said illuminating light is maintained and to adapt, in a second magnification range lying above said first magnification range, wherein the transmission of said viewing optic in said second magnification range decreases with increasing magnification, the size of said illuminated area while said irradiation intensity is simultaneously changed, so that the brightness impression of viewed images for the viewer is constant over said first magnification range and over said second magnification range.