Chen Xinwei, Zeng Lijiang
Opt Express. 2019 Feb 4;27(3):3294-3304. doi: 10.1364/OE.27.003294.
We propose a new recording system that employs a spherical wave and a toroidal wave to holographically record an aberration-reduced Rowland-circle spherical grating. Two more variables in this recording system are available for the design compared with a conventional symmetric dual-plane-wave recording system, which allows both the astigmatism and sagittal coma of the grating to be corrected to minimum. We derive the aberration coefficients of such grating and give the universal design principles for the recording system. An aberration-reduced grating used in a spectrometer equipped with linear array CCDs is then specifically designed and fabricated. The performances of the aberration-reduced grating and that of the conventional grating recorded by dual plane waves are compared in terms of the ray-tracing spot diagrams, and the photographed spectral images. The experimental results show that the spectral intensity of the aberration-reduced grating is about 4.5 times that of the conventional grating, while the resolution of the aberration-reduced grating is close to that of the conventional grating.
我们提出了一种新的记录系统，该系统采用球面波和环形波以全息方式记录像差减小的罗兰圆球面光栅。与传统的对称双平面波记录系统相比，此记录系统中有两个更多的变量可用于设计，这使得光栅的像散和弧矢彗差都能被校正到最小。我们推导了这种光栅的像差系数，并给出了记录系统的通用设计原则。然后专门设计并制作了一种用于配备线性阵列电荷耦合器件（CCD）的光谱仪中的像差减小光栅。根据光线追迹光斑图和拍摄的光谱图像，比较了像差减小光栅和双平面波记录的传统光栅的性能。实验结果表明，像差减小光栅的光谱强度约为传统光栅的4.5倍，而像差减小光栅的分辨率与传统光栅相近。
