Abstract: A device for controlling the brightness of an optical signal overlaid on a specimen image includes: a main light source configured to illuminate a specimen with a main light source illumination; a main objective, configured to generate the specimen image in a viewer beam path; and a beam splitter configured to reflect the optical signal into the viewer beam path, where the optical signal is generated by a display, and an illumination of the display is selectable among the main light source illumination, a secondary light source illumination, and both, and where the secondary light source illumination is adjustable as a function of the main light source illumination. The device may be a surgical microscope. The illumination of the display by the main light source illumination may be indirect, where the display is illuminated substantially by light reflections of the main light source illumination from the specimen.

Abstract: A stereo microscope comprises: a main objective; a main observation output configured so that a left-hand beam path and a right-hand beam path are formed between the main objective and the main observation output; at least one input reflection beam splitter in each of the left-hand and right-hand beam paths configured to reflect additional information into its corresponding beam path; at least one output reflection beam splitter in at least one of the left-hand and right-hand beam paths; at least one first switchable shutter associated with at least one of the left-hand and right-hand beam paths, located in front of a corresponding input reflection beam splitter; and at least one second switchable shutter associated with at least one of the left-hand and right-hand beam paths, located between the main observation output and a corresponding output reflection beam splitter.

Abstract: A stereo microscope comprises: a main objective; a main observation output configured so that a left-hand beam path and a right-hand beam path are formed between the main objective and the main observation output; at least one input reflection beam splitter in each of the left-hand and right-hand beam paths configured to reflect additional information into its corresponding beam path; at least one output reflection beam splitter in at least one of the left-hand and right-hand beam paths; at least one first switchable shutter associated with at least one of the left-hand and right-hand beam paths, located in front of a corresponding input reflection beam splitter; and at least one second switchable shutter associated with at least one of the left-hand and right-hand beam paths, located between the main observation output and a corresponding output reflection beam splitter.

Abstract: An optical viewing device in which image data are reflected in, for example a surgical (stereo)microscope, such that the brightness or color (temperature) of the overlaid information can be adapted to the needs of the viewer by means of a controllable reflected-in image illumination system (18). The additional light source can be used, simultaneously with and/or alternatively to the main light source (11), as illumination for a transmitted-light display (21). Alternatively, the light (2, 6) reflected from the specimen (13) can also be used as a light source for the display (21). This makes possible automatic regulation of the brightness of the reflected-in image for each portion of the overlaid image. Instead of a transmitted-light display (21), an incident-light display, for example a D-ILA, can also be used for the reflected-in image.