Research Of Bulk-Wave Acousto-Electro-Optical Effects

Theory and experiments of bulk-wave Acousto-Electro-Optical (AEO) device, involving one-dimension and multi-dimension, are systematically studied. The thesis includes the following contents: coupled-wave equation theory of AEO interaction, determination of the optimum operating mode of AEO device, geometrical relationships of the anisotropic Acousto-optic interaction, design and experiment of the AEO device. Finally, the optimum design of AO device with beam steering theory is also studied.Based on Acousto-optical coupled wave equation,the momentum mismatch is modified and Acousto-Electro-Optical coupled-wave equations are founded. For one-dimension Acousto- Electro-Optical effects, the momentum mismatch caused by ultrasonic wave is replaced by the summation of mismatch caused by ultrasonic wave and mismatch caused by electric field. For multi-dimension Acousto-Electro-Optical effect, the momentum mismatch is solely replaced by mismatch caused by electric field. Based on this, one-dimension Acousto- Electro-Optical coupled wave equation and multi-dimension Acousto- Electro-Optical coupled wave equation are founded and their diffractive efficiency formulas are also deduced respectively.Operating modes of LN one-dimension anisotropic AEO device and KDP two-dimension isotropic and anisotropic AEO device are determined. The principle to determine Electro-Optic operating mode is that the difference of two intrinsic diffractive index doesn't contain nature birefringence and the acousto-optic operating mode should achieve a higher acousto-optic merit value to improve the efficiency. Based on this, the optimum operating mode of LN anisotropic one-dimension AEO device is determined as: light promulgates along z axis, ultrasonic wave promulgates along x axis, and direct current electric field is loaded along y axis. The optimum operating mode of KDP two-dimension AEO device is: the light promulgates along z axis, direct current electric field is loaded along z axis too, a pair of slow wave promulgates in xoy plane, which are vertical to each other. The waves should be sheared waves for the anisotropic AEO device and longitudinal waves for the isotropic AEO device.Geometrical relationships of Anisotropic Acousto-Optic effect in LN crystal and KDP crystals are studied by tangent - match condition. Curves of incident angle vs. abaxial angle, diffractive angle vs. abaxial angle, extreme frequency vs. abaxial angle and acousto-optic merit vs. incident angle vs. abaxial angle are systematically gained and the design parameters are also calculated.LN one-dimension anisotropic AEO device and KDP two-dimension anisotropic AEO device are designed and made. The design job includes determination of optimum metal-plating structure of piezoelectric transducer and thickness of every metal-plating, calculation of length, width and thickness of piezoelectric transducer and acousto-electro-optic crystal.The central frequency and bandwidth of LN one-dimension anisotropic AEO device are determined by experiment. The changing rate of central frequency of LN...