摘要
多层膜光学元件的设计是基于理想的单色光进行的,然而光源发出的光束均存在光谱线宽,在非单色光条件下工作,元件的光学特性会偏离理论值。为了分析光束线宽对多层膜光学元件的光学特性影响,首先,基于薄膜辐射特性的部分相干理论,提出了准单色光束入射条件下多层膜光学特性计算方法;其次,通过数值模拟实验研究了光束线宽对窄带滤光片光学特性的影响。研究结果表明:随着线宽增大,滤光片透射通带的矩形度逐渐降低,半高全宽先降低后增大,其在滤光片的理论半高全宽附近取得最小值;光谱线型主要改变透射通带的透射率,对于透射谱线的矩形度以及半高全宽影响较小;为了保证窄带滤光片的通带形状,入射光束的线宽应当小于滤光片透射谱线的理论半高全宽的一半,光谱线型应当趋近于矩形线型函数。
Objective Multilayer films are critical optical elements for beam energy control in optical systems,and their quality directly influences optical system performance.Ideal monochromatic light serves as the foundation for the design of multilayer optical elements.But there is spectral linewidth in the actual beam.The optical characteristics of the element will differ from the theoretical value and may even result in total failure when operating in nonmonochromatic light.In the established convolution model,the calculation technique utilizes monochromatic light conditions to determine the interference superposition of beams in the film,hence disregarding the quasimonochromatic light interference effect.Based on this,the author proposes a calculation method for the optical properties of multilayer films under quasi-monochromatic light conditions and uses partial coherence theory to calculate the interference superposition of quasi-monochromatic beams.Methods A technique for estimating the optical characteristics of multilayer films in quasi-monochromatic lighting is proposed as a solution to this issue.To quantitatively quantify the linewidth and spectrum distribution of quasi-monochromatic light beams,the normalized power spectral density function is developed.Additionally,partial coherence theory is used to determine the irradiance of quasi-monochromatic light fields at the film interface.This study presents the design of a narrow-band filter with a passband ripple without collapse,a bandwidth of 4.29 nm,a center wavelength of 1064 nm,and a Rectangle degree of 0.66(Fig.2).Numerical simulation experiments are used to discuss how substrate thickness,spectral line-shape profile,and beam linewidth affect the optical characteristics of narrow-band filters.Results and Discussions As illustrated in Figure 4,for Gaussian,Lorentz,and rectangular line-shape,the Full Width at Half Maximum(FWHM)drops initially and subsequently increases as linewidth increases.The corresponding lowest values are 3.85 nm,4.08 nm,and 3.74 nm.And
作者
杨仕琪
曹袁睿
杨霄
白金林
孟阳
刘华松
Yang Shiqi;Cao Yuanrui;Yang Xiao;Bai Jinlin;Meng Yang;Liu Huasong(Tianjin Key Laboratory of Optical Thin Film,Tianjin Jinhang Institute of Technical Physics,Tianjin 300308,China;School of Astronautics,Harbin Institute of Technology,Harbin 150001,China;College of Materials Science and Technology,Nanjing University of Aeronautics and Astronautics,Nanjing 210000,China)
出处
《红外与激光工程》
EI
CSCD
北大核心
2023年第12期255-263,共9页
Infrared and Laser Engineering
基金
国家自然科学基金项目(61975150)。
关键词
窄带滤光片
功率谱密度函数
光谱线型
光学特性计算
数值模拟
narrow-band filter
power spectral density function
spectral line-shape profile
optical characteristics calculation
numerical simulation
