With a simple trick, it is possible to boost the activity of copper vapour laser, widely used in cutting materials for delicate structures in micro-fabrications. The trick is to minimise divergence of the laser beam thereby enhancing the power generated from it1.
To increase the efficiency of copper vapour laser, the researchers resorted to a special type of resonator. The enhanced copper laser vapour generated a maximum power of about 80 W (watt). On using this CAT-EYE resonator, the divergence of the laser beam was reduced to about 0.22 milliradians (mrad). This is around 20-fold reduction as compared to conventional plane–plane cavity. With unstable resonator, the researchers were able to reduce beam divergence to about 0.13 mrad with an output power of about 28 W.
The research is very significant as laser cutting is usually very narrow and can be controlled to less than one micron per laser pulse. This new ploy with the resonator seems effective in improving and controlling the laser beam divergence for copper vapour laser, the researchers say.
