Study on the maximum electric power supplied to copper bromide vapor lasers

Copper and copper-compound vapor lasers are most powerful in the visible spectrum with output power over 100 W. They offer unique properties including a laser beam with high coherence and convergence and high average output powers with relatively small dimensions. Recently, these lasers, and in particular the copper bromide (CuBr) laser, have been widely used as radiation sources and vapor brightness amplifiers in a new type of laser active optical systems, designed for the visual monitoring and control of fast processes shielded by intense background lighting. However, new problems arise with the development of such optical systems, related to the laser technology and the optimization of their operating parameters. Important operating characteristics of copper lasers include the input electric power and the gas temperature of the discharge. The upper limit of the laser power that can be supplied to the gas discharge is studied herein by considering the permissible thermal population thresholds of the lower level of the λ = 510.6 nm laser line. The application of enhanced analytical models based on a steady-state heat conduction equation and computer simulations enables the development of a methodology to determine the maximum possible electric power that can be supplied to the gas discharge, taking into account its radial distribution across the tube cross-section. This methodology is then applied to the case of an actual small-bore CuBr laser used as a brightness amplifier.