Jaeger W, Merté H J, Reiner J, Kratzer B
Klin Monbl Augenheilkd. 1979 Jul;175(1):1-11.
The previous magnifying spectacles and telescopic spectacles designed on the principle of the Galilean telescope have a magnification of only 2.5 x to 3 x for good image quality. New magnifying systems from Zeiss based on the Kepler telescope principle offer 3 x to 8 x magnification and thus cover the range between magnifying spectacles and operation microscopes and even come into the latter range. The following versions are available for ocular surgery: 1. Mounted on headband. 2. Fastened to the frame in front of the lenses. 3. Cemented into drilled holes in the lenses with additional horizontal connection of the magnifying systems. 4. Cemented into drilled holes in the lenses without horizontal connection. These versions offer different advantages and are selected according to the particular field of application and the refraction of the surgeon. With these compact and easily transportable stereomicroscopic systems the surgeon has complete freedom of movement being able to select the most convenient position at any stage of the examination or operation. Further applications of such stereomicroscopic spectacles beyond the field of ophthalmic surgery are mentioned.