摘要
由于具有较高的衍射效率,较强的布拉格波长选择性和角度选择性,反射型体布拉格光栅在光谱滤波与空间滤波领域得到了广泛应用。本文基于Kogelnik耦合波理论,得到了非倾斜反射型体布拉格光栅中描述折射率调制度、光栅厚度与布拉格条件下衍射效率之间关系的简化公式,研究了反射型体光栅的窄带滤波特性与角度滤波特性,分析了体光栅参数(光栅厚度、栅距与折射率调制度等)对光栅衍射效率,光谱带宽与角度选择特性的影响。结果表明,增大光栅厚度能提高光栅衍射效率,减小折射率调制度能减小窄带滤波器的滤波带宽与角度滤波器的角度选择范围。给出了滤波器设计中各光栅参数的计算方法,该研究结果为反射型体光栅滤波器的设计提供了理论依据。
Due to its high diffraction efficiency, strong wavelength selectivity and angular selectivity, reflecting volume Bragg gratings have been widely used in spectral and spatial filtering. Based on Kogelnik' s coupled wave theo? ry, a simplified formula describing the relationship between refractive index modulation, grating thickness and diffrac- tion efficiency in non-slanted reflection gratings is obtained. The narrow-band filtering characteristics and angular fil tering characteristics of reflecting uniform Bragg gratings were studied. The influences of volume grating parameters on diffraction efficiency such as grating thickness, grating period, refractive index modulation and more, the spectral bandwidth and angular selectivity were analyzed. The results show that the increase of grating thickness can improve diffraction efficiency of the gratings. And the decrease of refractive index modulation can reduce the filtering bandwidth of the spectral filters and the angle selection range of the angular filters. The calculation method of each grating parame ter in filter design is given. The research results provide a theoretical basis for the design of reflecting volume grating filters.
作者
郭立萍
葛筱璐
刘晓娟
GUO Liping;GE Xiaolu;LIU Xiaojuan(School of Physicsand Optoelectronic Engineering, Shandong University of Technology, Zibo Shandong 255000, China)
出处
《激光杂志》
北大核心
2019年第7期52-55,共4页
Laser Journal
基金
淄博市校城融合发展计划(No.2018ZBXC052)
国家自然科学基金(No.11704226)
山东省自然科学基金(No.ZR2017MA051)
关键词
布拉格衍射
耦合波理论
体光栅
滤波
Bragg diffraction
coupled wave theory
volumegratings
filtering
