科學界普遍透過月球表面的近紅外波段光譜識別礦物，由於每種礦物都具有獨特的光譜特徵，因此礦物很容易被分辨。高光譜儀亦可通過探測月球表面礦物和岩石反射的可見光至近紅外波段光譜資訊，來獲取物質組成和分佈情況，並藉由高光譜影像提供的精確光譜資訊更清楚地表徵和識別目標。
本文探討光譜儀的系統中，利用光柵方程式將入射光分光後，會形成一階及二階以上的光波，其中線性漸變濾波片(Linear Variable Filter, LVF)功能為保留光譜儀系統中光柵分光後之一階光波，而濾除二階及以上波長之光斑，用以探討二階線性漸變濾波器的穿透頻譜圖模擬設計。
本實驗元件應用於短波紅外光波段光譜儀，使用於業界廣泛使用的光學鍍膜設計軟體TF-Calc，以對稱膜堆設計並優化並分析高通濾波以及低通濾波線性漸變濾波片之線性變化，得知臨界波長λc對應之位置，求得相關係數R以確保線性度的可能性。為了達到帶通濾波線性漸變之效果，模擬高通濾波線性漸變濾波片需與低通濾波線性漸變濾波片重疊，針對不同高低通濾波之膜堆設計，能呈現不同半高全寬(Full Width at Half Maximum, FWHM)之大小與帶通濾波最高穿透率之波長位置，並分析帶通濾波片光譜分辨力(Resolving Power)解析度。
於高光譜儀成像系統上，本文使用光學模擬軟體TracePro進行高光譜儀之感測器能量接收模擬，並Ansys Fluent熱流動力學工程模擬軟體分析高光譜儀之熱能分佈與材料選用，用以驗證本研究開發之可行性與完整性。

The grating equations split the incident light and generate first-order and the above of the second-order wavelengths in a spectrometer system. Previously the development of a linear variable filter (LVF) was mainly designed high pass filtering. In order to reserve a first-order after the grating split it eliminates second-order and the above of second-order wavelengths in a spectrometer system.
This experimental component is applied to the shortwave infrared light band spectrometer, and its optical coating is designed with TF-Calc. The symmetrical membrane stack is designed, optimized and analyzed for high-pass filtering and low-pass filtering linear gradient filters. The linear change of the critical wavelength λc is known, and we can calculate the R-squared value to ensure the linearity. To achieve the effect of the band-pass filter, the analog high-pass linear variable filter needs to overlap with the low-pass linear variable filter. The membrane stack design for different high and low pass filters can present different size of Full Width at Half Maximum (FWHM) and the wavelength which position of the band-pass filter have the highest transmittance to analyze the resolution of the band-pass filter's spectral resolution (resolving power).
On the spectrometer imaging system, this paper proposes an optical simulation method, selects a suitable detector according to the width and band of the linear area of the film stack, establishes the detector coordinate system and simulate the ideal spectral response. Analyze the effect of different optical parameters and system assembly errors on the actual spectral response. The influence of the actual spectral response can be considered when the system is assembled, and the appropriate system parameters can be selected.

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