Continuous dye laser yields tunable output

If you want to make an organic dye laser operate continuously, just mix the dye with a little soapy water. That recipe worked for Otis G. Peterson, Sam A. Tuccio and Benjamin B. Snavely of the Eastman Kodak Research Laboratories. Since the group reported making a cw laser (Appl. Phys. Lett. 17, 245, 1970) it has managed to make it tunable in the range 5500–6500 Å and hopes soon to extend the work to other parts of the visible spectrum. Snavely says the dye laser should be tunable over the entire visible region. Although cw semiconductor lasers are tunable in the infrared, Snavely noted that the Kodak laser is the first cw tunable source in the visible range.