Chapter 1 - Ultraviolet Light

Abstract

Ultraviolet (UV) light has become important as the various technologies that are necessary to provide practical UV laser imaging and beam delivery systems have progressed, especially the light sources. UV light has been available only from low power lamps, thereby restricting the usefulness of the technology. The discovery and development of the excimer laser made possible the availability of intense ultraviolet light. Researchers explored and uncovered the unique properties of this new light source. As various phenomena involving UV energy and material interactions were discovered and optimized, practical applications emerged. This chapter discusses the UV spectrum, early UV lamp sources, laser physics and operating principles, and development leading to the discovery of the UV laser. UV light is available from a variety of sources, including naturally occurring UV light, UV lamps, and UV lasers. UV light from the sun is abundant, but cannot be easily or economically harnessed for the applications that have practical value. To a lesser degree, UV lamps have the same problem: they supply rich amounts of the ultraviolet wavelengths, but by the time the energy is collected and transmitted through an optical system, little energy is left to meet the demands of most commercial applications.