基于双波长强度调制的法布里-珀罗滤光器中心波长定标  

Center Wavelength Calibration of Fabry‒Perot Filter Based on Dual-Wavelength Intensity Modulation

作　　者：朱瑾 马琳[1,2] 金振宇 穆恒宇[1,2] Zhu Jin;Ma Lin;Jin Zhengyu;Mu Hengyu(Yunnan Observatories,Chinese Academy of Sciences,Kunming 650216,Yunnan,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院云南天文台,云南昆明650216 [2]中国科学院大学,北京100049

出　　处：《光学学报》2024年第24期177-184,共8页Acta Optica Sinica

基　　金：国家自然科学基金(12073074,11833010);国家重点研发计划(202103AD50013);云南省科技计划项目(202105AB160001);云南省科技人才与平台计划(202305AH340002);云南省兴滇英才人才培养计划(202305AS350029)。

摘　　要：法布里-珀罗(F-P)滤光器是太阳二维成像光谱观测系统的重要组成部分,为了实现高精度太阳二维成像光谱观测,要求F-P滤光器必须具有准确的中心波长。由于滤光器只能提供控制器数值,无法直接获取波长信息,提出一种基于双波长强度调制的定标方法,利用F-P滤光器强度调制的周期性和双波长强度调制的差异性,建立控制器数值和滤光器腔长及波长的对应关系,实现波长精确定标。在实验室开展F-P滤光器定标测试,测试结果表明,对于Hα谱线,滤光器的波长定标精度达到0.0093A,满足1 m新真空太阳望远镜(NVST)下一代二维成像光谱观测系统的指标要求。Objective The Fabry‒Perot(F-P)filter,with the advantages of narrow bandwidth,high transmittance,and large aperture,is an essential component in solar twodimensional imaging spectrometers.It is also a crucial optical element in the nextgeneration twodimensional imaging spectrometer for the New Vacuum Solar Telescope(NVST).To achieve highprecision solar spectrum observation,the F-P filter must have an accurate center wavelength.However,in practical applications,the filter can only provide controller values and cannot obtain wavelength information directly.Additionally,the accuracy and stability of cavity length are affected by material defects,component fatigue,and environmental changes,resulting in center wavelength drift.Therefore,the center wavelength of the filter must be calibrated.Traditional calibration methods require a stable continuous spectrum light source and a spectrometer or interferometer with a resolution higher than that of the filter,which are large and expensive.Currently,the common calibration method uses the sun as a standard light source,but this is limited by variations in the solar spectrum.We propose a novel method for calibrating the center wavelength of the F-P filter.This method is simple in structure and does not require additional spectrometers or interferometers,avoiding the problem of singlewavelength 2πentanglement and overcoming the limitations of solar spectral calibration.The calibration accuracy is better than 0.01Å,fully meeting the requirements of the NVST twodimensional imaging spectrometer.Methods Our method for calibrating the center wavelength of the F-P filter is based on the periodicity of the intensity modulation curve of the F-P filter.First,we measure the unit step of the controller using the adjacent peaks of the singlewavelength intensity modulation curve.The 2πentanglement problem is then solved using the dualwavelength intensity modulation curve,and the corresponding relationship between cavity length and the controller value is established according to the p

关 键 词：Fabry‒Perot滤光器 定标 腔长 中心波长 双波长强度调制 

分 类 号：P111[天文地球—天文学]