Bragg Cell on TeO2 for 2-D Deflector with Reduced Drive Power: Analysis, Design, and Experimental Examination

Abstract : The objective of this work is to study the mechanisms limiting the bandwidth of 2-D Acoustoptic Deflector (AOD) and to examine such a deflector experimentally. The work consists of three parts: (1) The construction of 2-D AOD was considered. The frequency characteristic was analyzed using the physical model of the plane light wave, interacting with the divergent sound beam inside the TeO2 crystal. The entire frequency characteristic has been calculated, taking into account the change of the light polarization. The dependence of the frequency characteristic on the acoustic power and constructive parameters of the acousto-optical element have been analyzed. (2) A technique for wide band matching of the high frequency LiNbO3 transducers that allows the exclusion of the impedance transformer has been described and used to match the acousto-optical element on TeO2. The calculated network was practically constructed and examined experimentally. (3) The 5.5 deg and 7.9 deg acousto-optical deflections were investigated experimentally. The frequency characteristics at various adjustment angles and drive powers have been measured and analyzed.