全息凹面光栅光谱仪具有平谱面、小型化、大孔径、高分辨率等优点。首先从信息光学的角度推导了全息凹面光栅的成像公式,在垂直于狭缝和平行于狭缝的平面上系统分析了全息凹面光栅光谱仪的成像性能;在垂直于狭缝的平面上,全息凹面光栅光谱仪具有良好的平谱面性;在平行于狭缝的平面上,全息凹面光栅光谱仪克服了传统平面光栅的谱线弯曲和色畸变,实现了谱线平直成像;此外指出全息凹面光栅光谱仪固有的弧矢场曲对视场扩展的限制。然后根据理论分析结果提出了结构对称消场曲的全息凹面光栅光谱仪的设计思想,利用ZEMAX软件优化设计了像差补偿型全息凹面光栅光谱仪。在保证相对孔径F#=3、光谱分辨率为20 nm/mm、空间分辨率小于25 μm等技术指标不变的前提下,设计了狭缝长度为0.4 mm的传统单球面镜全息凹面光栅光谱仪和狭缝长度为8 mm的像差补偿型全息凹面光栅光谱仪。结果表明,改进后的像差补偿型全息凹面光栅光谱仪成功地将视场扩大为单球面镜全息凹面光栅光谱仪的20倍。

Holographic concave grating (HCG) spectrometer has many advantages, such as flat-spectrum, miniaturization, large aperture and high resolution. Firstly,the imaging formula of HCG is deduced based on information optics and its imaging characteristics are analyzed in both perpendicular plane to the slit and parallel plane to the slit. In the perpendicular plane, HCG spectrometer has good flat-spectrum; in the parallel plane, HCG spectrometer overcomes the spectral line bending and chromatic distortion of the traditional plane grating and realizes the straight spectral line imaging. In addition, the restriction of the intrinsic sagittal field curvature of HCG spectrometer to the field of view expanding is pointed out. According to the theoretical analysis results, it is proposed that symmetrical structure eliminates field curvature of HCG spectrometer. Then the aberration compensation spectrometer is designed and optimized with the utilization of ZEMAX software. Both traditional single-spherical-mirror HCG spectrometer with 0.4 mm slit length and aberration compensation HCG spectrometer with 8 mm slit length are designed with the same relative aperture F# of 3, spectral resolution of 20 nm/mm and spatial resolution of less than 25 μm. The results show that the field of view of the aberration compensation HCG spectrometer is successfully expanded 20 times larger than that of single-spherical-mirror HCG spectrometer.