为解决传统Dyson成像光谱系统结构过于紧凑而难于实际应用的缺点, 通过减薄半球透镜厚度和偏置狭缝位置的办法, 将狭缝、像面与半球透镜之间拉开了足够的轴上距离和垂轴距离; 结合光程进行分析, 获得了改进后Dyson系统的消像散条件; 在半球透镜和凹面光栅之间增加两个球面透镜, 对轴上距离带来的额外球差和色差进行校正.结合改进的Dyson成像光谱仪和Schwarzschild双反射镜系统, 设计了宽波段、小F数高光谱成像仪光学系统.对一工作波段为320~1 000 nm的实例设计结果进行分析可知, F数为1.8的全系统像差得到充分校正, 全视场全波段调制传递函数值在0.5以上, 光谱分辨率达到3.6 nm.该系统可用于沿海环境的高光谱观测.

To solve the problems that the structure is too close to mounting the optomechanism for the engineering application, the bias slit and the thinned hemisphere lens were supplied to move enough lateral and axial air spaces between the slit, the imaging plane and the hemisphere lens. The stigmatic condition for the advanced Dyson system was obtained by the geometric optical path analysis. Another two spherical lenses were introduced between the hemisphere lens and the concave grating to eliminate extra spherical aberrations and chromatic aberrations brought by the axial air spaces. The optical system of the imaging spectrometer with small F number in a broadband was designed by the advanced Dyson spectrometer and Schwarzschild two mirrors system. An example operating in 320~1 000 nm with F number 1.8 was built. The results demonstrate that aberrations are totally corrected, the modulation transfer functions of all fields of view are larger than 0.5 in the waveband, and the spectral resolution is 3.6 nm. The proposed system can be used for the coastal ocean hyper-spectrum observation.