With wide applications of the near infrared acousto-optic tunable Filter（NIR-AOTF）spectral imaging analyzer in the infrared spectrum of a plurality of spectral region, it has put forward higher request on the spectral bandwidth, diffraction efficiency and power efficiency of NIR-AOTF. As the core component of NIR-AOTF, the 3 dBbandwidth of the ultrasonic transducer determines the diffraction spectrum range of NIR-AOTF, so the operating bandwidth of 3 dB loss can be improved by changing the lithium niobate film thickness of each transducer.Through the ultrasound transducer frequency characteristic analysis, the transducer loss and impedance frequency characteristics have been obtained. The matching network was designed and optimized to improve the spectral diffraction efficiency.