Fuzzy Logic Boosts Laser Performance

A team of researchers at Nanyang Technological University in Singapore has demonstrated that lasers controlled with fuzzy logic systems offer more stable output than optimized open-loop devices or those incorporating proportional integral derivative controllers.

In the February issue of Optical Engineering, the researchers reported that their pulsed nitrogen laser with a fuzzy logic controller displayed a pulse energy stability of 1.46 percent rms and a pulse width stability of 4.24 percent rms over 4000 shots.

They modeled the laser as a two-input, two-output system with Matlab Fuzzy Logic Toolbox software from The MathWorks Inc. of Natick, Mass., and defined the desired pulse energy and pulse width as 0.25 mJ and 1.9 ns, respectively. They suggest that the addition of a learning scheme, such as a neuro-fuzzy control algorithm, will further boost the laser's performance.