For the different consideration of the TeO2 acousto-optic material, there are several theories of the noncollinear acousto-optic tunable filter (AOTF) design. Three relationships of noncollinear acousto-optic interaction are analyzed in this paper. The results indicate that the P. A. Gass′ theory can describe the relationship of AOTF parameters, and the correlative equations are simple. On the basis of P. A. Gass′ theory, the optimization design method of the incident polar angle, the dispersion elimination and the geometry parameters are discussed. The theoretic index of the designed 0.8~2.0 μm noncollinear AOTF are better, indicating the applicability of P. A. Gass′ theory. The study is meaningful for pushing the widely applications of noncollinear AOTF.