摘要
设计了离轴全球面成像光谱仪和离轴校正透镜棱镜分光成像光谱仪两种光学系统.在离轴全球面成像光谱仪的基础上,提出了改进型离轴校正透镜光谱仪,仅采用一个色散棱镜,避免了大口径同心透镜;有效校正了大视场像差,色散非线性修正效果显著.通过调节离轴角和光谱仪的焦距控制了畸变,补偿了与波长相关的狭缝弯曲,减小了残余像差,并降低了整个光谱仪工程实施的难度.从工程合理性、加工可实现性和光学性能等方面比较了两个系统的特点,推导和给出了光谱分辨率和狭缝弯曲的计算结果.从设计结果看,改进型离轴校正透镜光谱仪的传递函数最小值大于75%,而离轴全球面成像光谱仪的最小值只大于60%.从加工难易程度看,离轴全球面成像光谱仪采用一个接近Φ200mm的石英透镜,其透射材料远不如改进型离轴校正透镜光谱仪透镜材料的均匀性和面形准确度高,而且大口径透镜大大增加了制备难度和成本.从工程布局看,改进型离轴校正透镜光谱仪充分考虑了与机械结构的匹配,狭缝与第一面反射镜的轴向距离较合理.从光谱特性看,两个光学系统的光谱分辨率结果基本接近,离轴全球面成像光谱仪光谱弯曲结果略好于离轴校正透镜结构.因此,综合比较得出离轴校正透镜光谱仪是最佳的选择方案,该系统可应用在短波红外波段的光谱成像的遥感探测.
The optical configurations of off-axis spherical lens and off-axis correcting lens imaging spectrometer are designed.Based on the optical system of off-axis spherical lens imaging spectrometer,the spectrometer with off-axis lens is designed.This system adopts an off-axis lens in order to adjust large field aberration and avoids large diameter concentric lens.One prism corrects nonlinear dispersion and meets the request of spectral resolution.Distortion is controlled through adjusting off-axis angle and mirrors＇ focus,which compensate spectral curve and decrease residual aberration.It is easy to reduce production difficulty.The characteristic of two systems is discussed from the aspects of engineering layout,production difficulty and image quality.And the result of spectral nonlinear and slit curve is shown.The minimum modulated transfer of off-axis spherical lens system is 75 percent better than the value 60 percent of off-axis correcting lens.The front system uses a silica lens which diameter is larger than 200 mm.The material uniformity and surface precision of the latter system is far better than the front system,and the production difficulty is decreased.The latter system considers the matching with mechanical structure,and it is more feasible for the distance between slit and the first mirror of latter system.The spectral resolution of front system is close to the latter,and the slit curve of the front system is slightly better than the latter system.The comparison shows that the latter is optimal optical layout,and it can be applied to remote sensing working at short wavelength.
出处
《光子学报》
EI
CAS
CSCD
北大核心
2010年第7期1334-1339,共6页
Acta Photonica Sinica
基金
国家高技术研究发展计划项目资助
关键词
棱镜分光光谱仪
离轴校正透镜
色散非线性
狭缝弯曲
Imaging spectrometer with dispersion prism
Off-axis correction lens
Spectral nonlinear
Slit curve
