1 - Introduction

Abstract

This chapter discusses tunable sources of coherent radiation and their performance. Tunable sources of coherent radiation are suitable for a wide range of applications in science, technology, and industry. The spectral coverage available from pulsed broadly tunable sources of coherent radiation is presented in the chapter. To determine an appropriate laser for a given application, the simplest and most efficient means to yield the required energy or average power in a specified spectral region should be identified. The selection of a particular pulsed laser should include parameters such as spectral region, pulse energy, average power, cost, and environment. The detection and assessment of the surface defects are accomplished using interferometry that applies tunable narrow-linewidth CW lasers. The surface treatment requires the use of pulsed lasers operating in a high pulse repetition frequency (PRF) regime. The subject of tunable semiconductor lasers is treated with emphasis on external cavity and wavelength tuning techniques.