A simple dye laser for demonstrations

A simple scheme is described for demonstrating laser generation of ($\lambda$ = 570 nm) in an ethanol solution of rhodamin 6G excited by a small N$_2$ laser LGI-21 ($P$ = 3kW, $\lambda$ = 337 nm). The solution is placed into a cell of 4–5 mm thickness with a silver or aluminum mirror and a quartz window at the ends. Excitation is produced by a beam focused by a spherical lens through the quartz window. Radiation from the dye laser leaves the cell at a small angle in the direction opposite to the exciting beam through the same lens and this produces collimated radiation which is then aimed in the desired direction by deflecting mirrors.