为实现大气层外太阳光谱辐照度(SSI)变化的长期例行监测,设计了一种星载宽光谱太阳光谱仪结构。全系统仅使用单片折反式曲面棱镜实现太阳光谱250～2500nm的分光,并通过棱镜转动实现谱平面上多探测器的同步扫描探测;同时基于Huygens子波点扩展函数(PSF)仿真了光谱仪的光谱响应函数(SRF)和光谱分辨率。分光棱镜在±2.5°扫描转角内的全谱段子午像差小于8μm;光谱分辨率在紫外谱段(250～400nm)为0.7～3.5nm,可见/近红外谱段(400～1000nm)为3.5～35.0nm,短波红外谱段(1000～2500nm)内为28.5～41.2nm。整个系统结构简单紧凑,性能稳定可靠,分光和像差校正能力满足大气层外太阳光谱辐照度长期监测需求。 In order to realize long-term routine monitoring of changes in atmospheric spectral irradiance (SSI) outside the atmosphere, a structure of a spaceborne broad-spectrum spectrometer was designed. The whole system only uses the monolithic transflective curved prism to realize the spectral resolution of 250-2500 nm in the solar spectrum and realize the synchronous scanning detection of multi-detectors on the spectrum plane by rotating the prism. At the same time, the spectrometer was simulated based on the Huygens wavelet expansion function (PSF) Spectral response function (SRF) and spectral resolution. The full-spectrum radial differential of the dichroic prism at a scan angle of ± 2.5 ° is less than 8μm; the spectral resolution is 0.7-3.5nm in the ultraviolet (250-400nm) range and 3.5-3.5nm in the visible / near infrared (400-1000nm) ~ 35.0nm, the shortwave infrared spectrum (1000 ~ 2500nm) within 28.5 ~ 41.2nm. The whole system has the advantages of simple and compact structure, stable and reliable performance, and the ability of spectroscopic and aberration correction to meet the long-term monitoring needs of solar spectral irradiance outside the atmosphere.