PIEZO-OPTICAL SURFACES

We present a method of construction of piezo-optical surfaces (POS) which consists in the finding of the difference of position vectors of the optical indicatrix perturbed by a mechanical stress and a nonperturbed one. It is proved that the method of construction of the indicative surfaces (IS) of the longitudinal and transversal piezo-optical effects (POE) is a partial case of the offered method. The examples of POS are adduced for cubic crystals BaF2 and KBr which concern to the symmetry class m3m. It is shown that the transformation law of components of the tensor of piezo-optical coefficients (POC) upon a rotation of the coordinate system is identical to the difference of position vectors of the optical indicatrix perturbed by the tensor of POCs and those of a nonperturbed one. This statement is spread on other physical effects induced in crystals by external fields.