a lamp in which electric current arcs across two electrodes, providing an intense light source for illuminating both transparent copy (negatives, colour transparencies) and reflective copy (flat original art), and for burning-in plates
see gas discharge lamp) - a gas discharge lamp in which light is produced by the passage of electricity, through a gas, across two electrodes enclosed in a quartz envelope; high-pressure arc lights (such as mercury vapor lamps, high-pressure sodium arc lamps, and metal-halide arc lamps) produce light in a physically small bulb of high-pressure gases; low-pressure arc lights (such as fluorescent lights, germicidal ultraviolet lamps, and neon sign lamps) employ a physically big tube of low-pressure gas plasma.
Often used as a light source on a microscope, an electric light in which a current traverses a gas between two incandescent electrodes and generates an arc that produces light. Arc lamps have a limited lifetime. Also called an arc light.
An arc lamp is the general term for a class of lamps that produce light by an electric arc (or voltaic arc). The lamp consists of two electrodes typically made of tungsten which are separated by a gas. The type of lamp is often named by the gas contained in the bulb; including neon, argon, xenon, krypton, sodium, metal halide, and mercury.