量子点光谱成像技术与重建仿真

摘要

为满足机载星载平台对光谱成像系统紧凑型和轻量化的需求,克服当前光谱成像技术分光系统结构复杂、成本高的不足,提出了基于量子点材料的光谱成像技术方案.将条带状的量子点阵列片放置于前置镜焦面前,利用量子点材料对光谱的吸收特性对探测目标的入射光谱进行调制,使用最小二乘法建立探测目标的光谱重建模型,采用推扫的方式获取数据并进行光谱重建可以获得目标光谱和空间信息.量子点光谱成像技术具有光谱分辨率高、能量利用率高、体积小、光谱范围宽和成本低等优势.分析了不同光谱谱段间隔和噪声等因素对重建光谱分辨率的影响,以及对重建光谱准确性或者失真度的影响.分析得出谱段间隔越低,光谱分辨率越高;重建的准确性和分辨率随着噪声水平的增大而降低;适当的提高谱段间隔,可以提高重建的准确性.将已知数据立方体和它的仿真结果进行对比,可以看出还原得到的量子点光谱图像质量较好,验证了该技术的可行性.量子点材料为光谱成像技术提供了新的途径,在航空航天等小型化光谱遥感领域具有极大的应用潜力.%In order to meet the requirement of compact type and lightweight for spectral imaging system in airborne and satellite platform,and to overcome the limitations of optical splitting system in current spectral imaging technology such as complex structure and high cost,for the first time we present the design of spectral imaging based on quantum dots.In this method,a strip of quantum dots array is placed in front of the focal plane of telescope lens and absorption properties of quantum dots mate-rials is applied to modulate the incident spectrum of the target,then least square method is applied to establish the spectral recon-struction model of the target.Finally,the spectral and spatial information of the target is obtained with the method of push broom and spectral reconstruction.The quantum dots spectral imaging technology has the advantages of high spectral resolution, high energy availability,small size,wide spectral range and low cost.More important,the effects of different spectral intervals and noises on the reconstructed spectral resolution and their impact on the accuracy or distortion of the reconstructed spectra are analyzed.The results show that the spectral resolution increases with the decrease of the spectral interval,and the accuracy and resolution of the reconstructed spectrum are reduced with the increase of the noise level.What's more,the accuracy of recon-struction can be improved by appropriately increasing the spectral interval.With a comparison of the simulation results with the known data cube,the feasibility of the technology is verified,and the results show that the quantum dots spectral imaging pos-sesses higher quality.In conclusion,quantum dots provide a new approach for spectral imaging technology,which has wide ap-plications in the field of aerospace and other miniature spectral remote sensing.