Embedded Control System for Flash Lamp Pumped Solid-State Nd:Glass LASER Power Supply

Abstract

High-power solid state Nd:glass lasers find applications in diverse fields of industry and technology[1]. These lasers are pumped by flash lamps of different sizes. Flash lamps are intense source of wideband light ranging from infrared to ultraviolet. Nd: glass absorption band lies within the emission band of Xenon flash lamps[2]. This paper reports the development of a closed loop standalone embedded control system and the Graphical User Interface (GUI) for flash lamp power supply. The GUI is developed using the Processing software, which is an open-source Java-based software. The microcontroller-based control system continuously monitors and controls the charging process of the energy storage capacitor banks. After the user defined energy is stored on the capacitor banks, the control system generates trigger signals to couple the stored energy to flash lamp load and thereby convert the electrical energy into intense light pulse for pumping of the laser medium. The control system is tested for ruggedness and reliable operation under high EMI generated by switching of several power electronics devices and electromechanical relays. The Graphical User Interface allows a user to interact with the system through visual indicators and buttons. It also displays the time domain characteristics of Flash Lamp current, which is measured with the help of a current transformer. The control system design, product cycle and test results are discussed in this paper.