DEVELOPMENT OF LONG PULSED ND:YAG LASER SYSTEM

Abstract

The Nd:YAG laser with long pulse duration can be produce by using an appropriate pumping scheme. The purpose of this study is to construct a high voltage power supply for laser system. In this attempt multiple-mesh pulse forming technique was performed to obtain electrical pump pulses with a more rectangular shape and long normal-mode laser pulses at constant power. The flashlamp driver was designed with variable input energy. The developed flashlamp driver composes of five major electronic circuits. There are comprised of signal controller device, simmer power supply (SPS), trigger pulse ignition circuit, capacitor charging power supply (CCPS) and multiple-mesh LC pulse forming network (MPFN). The construction of the flashlamp driver is started by designing a signal controller. The controller generated a small voltage to activate the electronic components such as silicon controlled rectified (SCR) and transistor. The ignition circuit was used to ignite xenon gases which responsible to form ionized spark streamer between the two electrodes of flashlamp. A Low dc current was induced by the simmer power supply to sustain the flashlamp in simmering mode. The capacitor charging power supply was used to supply electrical power to capacitor bank within specific time. Nd:YAG laser oscillator was aligned and pumping by the new developed flashlamp radiation. As a result Nd:YAG laser beam was generated having fundamental wavelength of 1064 nm and 650 microsecond of pulse duration with maximum output energy of 250 mJ.