介绍了一种采用氧化碲晶体做声光介质材料的大孔径中波(3~4.5 μm)声光可调滤光器。通过优化设计, 其通光孔径可达20 mm×20 mm, 与常用声光可调滤光器(光孔径10 mm×10 mm)相比, 其光通量提高了3倍。这种声光可调滤光器是针对入射o光进行设计的, 其采用单片换能器结构。结果表明, 通过优化设计, 该大孔径中波声光可调滤光器实现了滤光范围为3.0~4.5 μm, 分离角为5.25°, 衍射效率大于60%, 光谱分辨率小于45 nm。

In this paper, a large aperture medium-wave (3~4.5 μm) acousto-optic tunable filter using tellurium oxide crystal as acousto-optic medium material is introduced in this paper. Through optimizing the design,its clear aperture has reached 20 mm×20 mm,and its luminous flux has increased by 3 times compared with the commonly used acousto-optic tunable filters (optical aperture 10 mm×10 mm).This acousto-optic tunable filter is designed for the incident o-light, which adopts a single-chip transducer structure. The results show that through design optimization, the filter achieves a filter range of 3.0~4.5 μm,a separation angle of 5.25°,a diffraction efficiency of greater than 60%,and a spectral resolution of less than 45 nm.