The effect of incident angle of pumping light to cholesteric liquid crystal

Optical characteristics research was carried out for the tunable laser of dye doped cholesteric liquid crystal. Based on the characteristic that pitch of the dye doped cholesteric liquid crystal varyed with the incident angle of pumping light, emission characteristics of the tunable laser of dye doped cholesteric liquid crystal were studied. Taking the mixture of laser dye and nematic liquid crystal and left-handed chiral additive as the layer of gain medium, wavelength tunable laser was prepared. The laser sample pumped by 532nm Nd : YAG pulse laser has the following optical characteristics: the wavelength of the emission laser was tuning from 647.38 to 658.11nm with the incident angle of pumping light, reaching 10.73nm.