Bi₁₂GeO₂₀（BGO）crystals have fortunate combi-nation of photorefractive, electrooptic and other properties making it promising materials for optoelectronics. Bi12GeO20 single crystal is the most popular photorefractive crystal. This prop-erty makes it possible to create spatial distribu-tion of refractive index in the crystal and can be used in wide variety of devices including spatial light modulators, optical memory, holography, phase conjugation etc. The Bi12GeO20 crystals are also piezoelectric, show strong electro-opti-cal and acousto-optical effects, and find limited use in the field of crystal oscillators and SAW devices.