Flexible optical pulse generation for laser micromachining using FPGA board with integrated high-speed DAC

Vol. 1 No. 2

Year: 2013

Issue: Apr-Jun

Title : Flexible optical pulse generation for laser micromachining using FPGA board with integrated high-speed DAC

Author Name : Chu En Ong, Dr. Teh Peh Chiong , Yeap Kim Ho , Dr. Lee Sheng Chyan

Synopsis :

This paper describes the novel approach of using a custom Field Programmable Gate Array (FPGA) board to generate digital arbitrary waveforms which is subsequently converted into analog waveforms via a high speed Digital-to-Analog Converter (DAC) IC. The FPGA codes are designed and optimized to generate very fast rise/fall times waveforms with the flexibility to vary both the pulse duration and pulse frequency in real time through a microcontroller with serial interface. These custom defined waveforms are then used to generate high intensity laser pulses when connected to a 1064nm fiber laser source. These pulsed laser sources have potential industrial applications in precision laser micromachining, where the high thermal intensity of the laser pulses can be used to perform ablation, cutting, drilling or annealing of processed materials. By able to tailor the shape of the delivered laser pulses, this will lead to reduction in processing time, improves the efficiency of material removal and the quality of the end product. Our custom board can generate arbitrary tailored pulses as short as 10ns and the longest pulse is 150ns. The pulse repetition rate can be tuned from 100kHz to 10MHz.