The Design Of Miniature Multispectral Camer System

Since it's inception,imaging spectrometers have been used in the field of space remote sensing.With the gradual miniaturization of the platform,such as small satellites,unmanned aerial vehicles and other small platforms,as well as the needs of field applications,the demand of miniature imaging spectrometer is more and more prominent in agriculture,military,medicine,scientific research and other areas.In this paper,the system parameters and spectral mode of the miniaturized spectral camera are calculated and analyzed.Taking into account the high energy transmission,wide spectral width,simple structure and stable performance of the prism,the prism are used as beam splitting component.In order to solve the problem of nonlinear dispersion,we choose to use double Amisi prism.The vertex angle and the material of the double Amisi prism are calculated,and it's smile,keystone and angular dispersion rate are simulated and analyzed in Zemax software.The spectral camera consists of three parts: front telescopic system,collimating system and collection system,each of them is designed separately.According to the technical requirements,the technical parameters of the front telescopic objective are determined.And the technical parameters of the collimation system and the collection system are determined based on the field and aperture matching principle.The double-Gaussian structure is chosen as the initial structure for the front telescopic system,and two patent structures are selected for the collection system and the collimation system after the parameter analysis.The wave band of the designed system is 400 nm to1000nm,and focal length is 34.51 mm,the F number is 3.47.And the spectral resolution is4nm@400nm and 18nm@1000nm,and the MTF curve of each band is basically greater than0.3 at 90lp/mm,which satisfies the requirement of the system.To meet the miniaturization requirement,The total length of the system is 294 mm.In the process of tolerance analysis,the effects of component processing and actual material error on the spectral image quality of the spectrometer are discussed respectively.