Acousto-optic k-space filtering for multifrequency laser beam shaping

One of emerging applications of acousto-optic tunable filters (AOTFs) is spatial filtering of optical beams. A noncollinear AOTF has a tunable ring-shaped transfer function determined by geometry of the refractive index surface in a uniaxial crystal. We rigorously derive the geometrical parameters of the AOTF's elliptic transfer function under noncritical phase matching condition in uniaxial crystals. This basic family of transfer functions can be used for synthesis of axially symmetric transfer functions with the help of multifrequency ultrasonic signals. A two-color tunable optical trap configuration is proposed based on a single AOTF used for laser beam shaping.