空间光谱耦合型多光谱相机的辐射定标  

Radiometric Calibration of Spatial⁃Spectral Coupling Multispectral Camera

作　　者：吴旋 杨斌 李先峰[1,3] 张军强 卢天姣[1,2] Wu Xuan;Yang Bin;Li Xianfeng;Zhang Junqiang;Lu Tianjiao(Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences,Changchun 130033,Jilin,China;University of Chinese Academy of Sciences,Beijing 100049,China;Changguang Yuchen Information Technology and Equipment(Qingdao)Co.,Ltd.,Qingdao 201713,Shandong,China)

机构地区：[1]中国科学院长春光学精密机械与物理研究所,吉林长春130033 [2]中国科学院大学,北京100049 [3]长光禹辰信息技术与装备(青岛)有限公司,山东青岛201713

出　　处：《光学学报》2024年第23期76-85,共10页Acta Optica Sinica

基　　金：国家重点研发计划(2022YFF1302000);吉林省科技发展计划项目(20230201036GX);青岛产业领军人才项目;泰山产业创新领军人才项目。

摘　　要：为了实现空间光谱耦合型多光谱相机的高精度光谱辐射测量,构建辐射响应模型并提出了一种辐射定标方法。通过研究空间光谱耦合型多光谱相机的分光原理和成像过程,根据辐射传输理论推导建立其完整的辐射响应模型。基于所构建的辐射响应模型,提出采用多光源组合的实验室辐射定标方法,实现光源在光谱与辐射两个维度的同时变化,从而建立关于辐射响应的超定方程组,通过全链路光谱辐射传输计算辐射响应系数的初值,并采用梯度下降法解算辐射响应系数的最优解。分别从实验室和外场验证了辐射响应定标系数的准确性。针对空间光谱耦合型多光谱相机,构建的辐射响应模型及提出的辐射定标方法消除了不同波段辐射响应重叠带来的影响,以保证该类型多光谱相机的光谱辐射测量精度。Objective Spatial-spectral coupling multispectral imaging is an innovative technology that integrates spatial and spectral information using color filter array sensors and multi-bandpass narrowband filters.This approach allows each pixel to capture data from multiple spectral bands.Due to the inherent coupling of spatial and spectral data,traditional radiometric calibration methods are insufficient for accurately determining radiometric response coefficients.Research on the calibration of such multispectral cameras remains limited.Current methods often focus solely on spectral response,using theoretical energy contribution ratios for each band as decomposition coefficients.However,these methods lack a well-defined radiometric response model and have not undergone sufficient experimental validation,leading to inaccuracies.Therefore,further research is needed to develop precise calibration methods and to solve for accurate radiometric response coefficients in this multi-band spatial-spectral coupled imaging system.Improving the radiometric accuracy of these systems will ensure reliable data for a wide range of applications.Methods In this study,we use a four-channel multispectral camera to construct a radiometric response model based on radiative transfer theory,describing the complete spectral radiative transfer process.A laboratory radiometric calibration method using a combination of multiple light sources is proposed,enabling variation in both the spectral and radiometric dimensions.This approach generates an overdetermined system of equations for the radiometric response coefficients.By calculating the energy contribution ratios for each band from the spectral response and converting these ratios into initial estimates of the radiometric response coefficients,the method avoids incorrect local optima when solving the overdetermined equations.The gradient descent method is then applied to compute the optimal radiometric response coefficients,ensuring practical physical relevance.This approach,which integrates th

关 键 词：多光谱 耦合 辐射响应模型 辐射定标 梯度下降法 

分 类 号：O432[机械工程—光学工程]