摘要 |
A source of radiant energy is combined with spaced apart reflecting surfaces which are sections of paraboloids of revolution and which have a common focal point but differing focal lengths. Radiant energy is reflected in substantially parallel rays and passed through radiation transmitting means which include radiation controls zones. The reflecting surfaces and the radiation transmitting means are mounted for rotary displacement of one relative to the other to vary the distribution pattern, intensity, color, and other characteristics of the reflected radiant energy in a unique manner. Radiation output from the source of radiant energy may be instantly tailored to a task at hand such as may arise, for example in theatrical lighting, mine lighting, police and surveillance work, military operations, fire fighting, sports activity, illumination of recreational areas and the like. By means of the unique construction and arrangement of the reflecting and transmitting components, it becomes possible to achieve a relatively high degree of efficiency and operating life in a range of luminaire sizes which can be manufactured on a commercially feasible basis. |