New xenon compact- arc projection lamps for horizontal operation

Xenon compact arc lamps are used increasingly instead of carbon arcs in motion- picture theater projectors and studio- lighting equipment. Such lamps have to perform with great reliability and must operate in horizontal position in order to be economic and efficient in up- to- date optical systems. The properties of four new lamps types are described that meet these requirements. Three of these lamps are in the medium wattage range between 2000 and 4500 w and have conventional radiation- cooled electrodes. The fourth type can be operated reliabily with inputs from 10 to 25 kw and has liquid- cooled electrodes.