Calculation of the optical density and relaxation time in BSO crystal

The change of optical density in a pure bismuth silicate oxide crystal that exposed to the radiations with wavelengths (510, 530, 540 and 560nm) are studied. It was shown that the change of optical density in the crystal increase with decreased incident wavelengths. The effect of the intensity of the incident radiations on the change optical density is studied. The relaxation time of this crystal has been discussed.