声光可调谐滤波器是一种利用反常声光作用原理研制的分光元件, 它在众多领域中广泛应用。光谱分辨率是评价声光可调谐滤波器性能的主要指标之一。系统分析了影响光谱分辨率的诸多因素, 指出通过优化单一的声光可调谐滤波器的参数设计在光谱分辨率提高方面受到制约。提出一种能够有效地提高光谱分辨率的新方法——二次滤波法。通过阐述二次滤波法的基本原理以及讨论利用二次滤波法来实现光谱分辨率提高的关键技术环节, 说明了利用该方法提高声光可调谐滤波器光谱分辨率的可行性和优越性。二次滤波法为声光可调谐滤波器光谱分辨率的提高开辟了新思路。

The acousto-optic tunable filter (AOTF) is one kind of prismatic elements which is developed by the abnormal acousto-optic interaction principle, it has wide applications in many fields. The spectral resolution is one of the key index for evaluating the performance of the acousto-optic tunable filter. We have analyzed the factors that were connected with the spectral resolution. And we have pointed out that the improvement of the spectral resolution was limited through optimizing the design parameters of a single AOTF. A new method called “double filtering” that can effectively enhance the spectral resolution is presented. The principle of double filtering method is described. The main technology of improving the spectral resolution by double filtering method is discussed. The feasibility and the advantage of this method on the spectral resolution improvement are confirmed. The double filtering method provides a new idea for the improvement of the spectral resolution.