On the wave field in the small neighbourhood of the point of incidence of the limiting ray

The plane scalar problem of refrecting highfrequency wave defined by its ray expansion by a curvilinear interface is considered. It is assumed that the velocity in the medium where the refracted wave propagates is greater than the velocity where the incident wave propagates. It is assumed also that a point on the interface exist such as on one side of it the ordinary refraction takes place and the complete internal reflection of the incident wave on another side of the point takes place. It is deduced an analutical formula for the wave field in a small neighbourhood of this point.