I want to steer laser beam in 2D plane , but I do not want to use mechanical steering for its enormous problems and disadvantages.
An alternative to an acoustic-optic modulator is the electroptic deflector. There are a few types but the readily available type uses a quadrupole electric field on a lithium niobate crystal. This generates a linear refractive index gradient in one plane that can be adjusted on a ultra fast time scale. This gives the ability to change the deflection angle of a suitably polarised beam propagating down the quadrupole axis. With fast pulse generators the deflection speed can be good enough to achieve deflection by several diffraction angles in perhaps 10 ps.
Optical streak cameras have been made using this technology. In practice the amount of information hat can be put through such a streak camera is significantly less than a standard image convertor camera.
The effectiveness always comes down to the electro-optic coefficients of the material and this limits their usefulness.
The advantage over a non resonant acoustic-optic modulator is that the deflection is immediate. There is no acoustic delay and the deflection speed can be very high. The disadvantage is the high voltage needed.
Look for papers by Clive Ireland. The device is made by Leysop.
There are other types. Some work at Souhampton university involving poled material gave promising results but in the end the numbers were no better.
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