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可调谐声光滤光器（简称ＡＯＴＦ）的优点是具有很高的集光能力，不仅可用来分析光源的光谱成分，而且可立即得到彩色图像的分色像。近来，国外正兴起用ＡＯＴＦ来制造光谱分析仪；利用ＡＯＴＦ的电调谐分光作用，辅以计算机控制，完成信息的实时处理。本文将通过对ＡＯＴＦ参数的计算，讨论声光滤光器各参数对光谱仪性能的影响。由于氧化碲晶体的慢切变波具有较大的声光优值，目前声光滤光器的制造基本上都用氧化碲晶体。下面讨论用氧化碲晶体制造的１．６°、１１．９°、１２．９°切向这三种常用的ＡＯＴＦ参数。１三种切向ＡＯＴＦ调谐性能的比较计算公式：ｆ＝Δｎｂ（λ）ｖ（α）／λ［］·ｓｉｎ２θｉ／ｓｉｎ（θｉ－ｘ）［］其中Δｎｂ是由于双折射引起的折射率差，ｖ是超声波在晶体中的声速，θｉ为光入射角，α为切向角，λ为光波长。计算发现，对１．６°切的ＡＯＴＦ来说在λ＝４００．０～７００．０ｎｍ时ｆ＝１００～４５ＭＨｚ；随光波长变长调谐频率降低，当它在长波长时要达到一定的分辨率时其调谐频率间隔也越窄，因而从驱动电源制作的难易程度来说１．６°切的ＡＯＴＦ只适合用于可见光范围。而１２．９°切ＡＯＴＦ，λ＝１～２．５μｍ时，ｆ＝９２～３５ＭＨｚ；１１．９°?
The advantage of tunable acousto-optic filters (AOTFs) is that they have a high light-gathering capability and can be used not only to analyze the spectral components of a light source, but also to obtain color separations of color images immediately. Recently, foreign countries are starting to use AOTF to manufacture spectrum analyzers. By using AOTF’s electrical tuning spectroscopy and computer control, it realizes the real-time processing of information. In this paper, the AOTF parameters will be calculated to discuss the parameters of the acousto-optic filter on the performance of the spectrometer. As the slow-shear wave of tellurium oxide crystal has a larger acousto-optic excellent value, the present acousto-optic filter is basically made of tellurium oxide crystal. The following three commonly used AOTF parameters of 1.6 °, 11.9 °, 12.9 ° tangents made with tellurium oxide crystals are discussed below. 1 tangential AOTF tuning performance comparison formula: f = Δnb (λ) v (α) / λ [] · sin2θi / sin (θi-x) [] where Δnb is the refractive index difference due to birefringence, v is the speed of sound in the crystal, θi is the angle of incidence of light, α is the tangential angle, and λ is the wavelength of light. It is found that f = 100 ~ 45MHz for λ = 400.0 ~ 700.0nm for AOTF of 1.6 °; tuning frequency decreases as the wavelength of light becomes longer, and when it reaches a certain wavelength The narrower the tuned frequency spacing is, so the 1.6 ° cut AOTF is only suitable for the visible range from the ease of making the drive power. While 12.9 ° cut AOTF, λ = 1 ~ 2.5μm, f = 92 ~ 35MHz; 11.9 °?