Device for preventing clouding of an observing window

摘要

The present invention discloses a device for preventing clouding of an observing window, utilizing heat rays of a light source. A converter is provided near the observing window for changing light into heat and the light is guided to said converter from light transmitting optic bundles. Then, a part of the light is changed into heat by this converter and the observing window is warmed by the heat in order to prevent the clouding.