Lasing efficiency and tuning range of lasers with dynamic distributed feedback

A study was made of a dye laser with dynamic distributed feedback. The choice of the material and vertex angle of an isosceles prism, through whose symmetrical faces excitation by an <i>s</i> -polarized wave took place, reduced the losses at the three interfaces to 2% over the whole range of lasing wavelengths 400-1000 nm. The lasing efficiency and tuning range of the laser were measured experimentally as a function of the contrast of the interference pattern of the pump field. It was found that in the nonlinear region of the dependence of the laser output energy on the pump energy the tuning range was constant while the lasing efficiency increased with decreasing contrast. In the linear region, there was narrowing of the tuning range at a constant lasing efficiency. The experimental results were obtained using polymethine dyes and a ruby laser.