LIGHT SOURCE UNIT FOR EXPOSURE

摘要

A light source unit for using exposure in a photomechanical process provided with a light emitting tube (1) insulated against cooling liquid and having a light transmissive jacket tube (2) fixed surrounding the light emitting tube (1) and letting to light of wavelength desirable for exposure of the objects to be irradiated pass through it by absorbing light component of undesirable wavelength where the energy of absorbed light is removed by cooling liquid passing through therein. The unit also has a circuit for preventing a danger of electric shock by interrupting electric current of the electric source owing to the action of leak current detector by the action of current leaked from the terminals and others of said light emitting tube.