An important contribution to the development of the rapid crystal growth methods from solutions was made by O.M. Ansheles, V.B. Tatarski, and A.A. Shtenberg (1945). One of the new rapid methods was suggested for growth of oriented KDP crystals in form of wafers of the specified size . A seed device was designed in such a way that the shaped crystal grew between two disks placed at a given distance one over another. The structure of the grown crystals was investigated by the methods of X-ray topography, anomalous birefringence, selective etching, spectrophotometry. The sectorial and zonal inhomogeneities produced by some defects with a density of about 104 cm-2 were revealed. The origin of these defects is still under determination. The growth sectors of a bipyramidal face appear to be the most inhomogeneous in this regard. The material of the growth sectors of a bipyramidal face has the highest UV transmission coefficient, similarly to the results reported in . The samples have a low value of anomalous biaxiality (less than 20Т) and uniformly oriented along z-cut planes of optical axis.