The present invention relates to an illuminating device for an operation microscope, having a main objective for two stereoscopic observation ray paths and a source of light which includes a light guide for delivery of the light.
In operations in the fields of otorhinolaryngology, neurology and gynecology, operation microscopes must permit adjustment of both large and very small illuminated fields.
Federal Republic of Germany G 8,713,356.3 discloses an illuminating device for operation microscopes whereby it is possible to obtain different diameters of illuminated field with an invariable optical system. This known illuminating device has the disadvantage that its expansion factor does not fully satisfy the requirements specific to operations of the character indicated.