Optical characteristics of TlBr crystals grown in various ambient

The present growth technology of TlBr detector crystals cannot provide the required quality. Its further development requires considerable studies of characteristics of the crystals, grown in various conditions, including optical methods. Optical characteristics were measured for TlBr crystals grown by the Bridgman technique in various ambient atmospheres: vacuum, Ar and air. The growth atmosphere had a profound influence on short-wave edge spectral transmission and on light scattering at a wave length of 0.63 μm. The measurements prove that the least abrupt border short-wave transmission and the greatest light dissemination are characteristic of crystals which have been grown in vacuum. Crystals received in air have the best optical characteristics. A model of the influence of the atmosphere on the optical characteristics of crystals is presented.