基于无透镜散斑图像编码的集成式光谱检测  

Integrated spectral detection based on lensless speckle image coding

作　　者：周天彪 黄思远 文龙 陈沁 Zhou Tianbiao;Huang Siyuan;Wen Long;Chen Qin(Guangdong Provincial Key Laboratory of Nanophotonic Manipulation,Institute of Nanophotonics,College of Physics&Optoelectronic Engineering,Jinan University,Guangzhou 511443,China)

机构地区：[1]暨南大学物理与光电工程学院纳米光子学研究院广东省纳米光学操控重点实验室,广东广州511443

出　　处：《红外与激光工程》2024年第3期175-183,共9页Infrared and Laser Engineering

基　　金：国家自然科学基金项目(62220106001)。

摘　　要：近年来,片上光谱检测技术由于其优异的集成特性在各种应用中引起了广泛的关注。得益于集成在各类便携式平台的低成本图像传感器,与波长相关的图像编码技术成为一种新兴的集成式光谱检测方法。为了准确地对图像中的光谱信息进行解码,通常需要物镜和较大的工作距离,这些都不可避免地增加了光学系统的复杂性和整个检测系统的尺寸。文中提出了一种基于卷积神经网络算法的新型散斑图像编码技术,通过将纳米散射结构直接集成到图像传感器表面进行散斑成像,实现了无需光学镜头的片上集成式光谱检测功能。这种高集成、低成本的光谱检测方法和器件利用先进算法克服了有限硬件资源造成的弱光谱检测能力,有望在现场快检和分布式传感网络等领域得到应用。Objective In recent years,on-chip spectroscopy has garnered considerable interests across multiple applications,primarily owing to its exceptional integration capabilities.Benefiting from mature image sensors with millions of pixels,wavelength-dependent image coding technology has emerged as a promising integrated spectroscopy method.However,achieving accurate decoding of spectral information in the images typically requires objective lenses and larger working distances,thereby increasing both the complexity of the optical system and the overall size of the inspection system.This limits its use in portable platforms such as mobiles.The aim of this work is to develop a lens-free image encoding method for on-chip spectroscopy and to address how to extract accurate spectral information from encoded images with high correlation.Methods A lens-free speckle image encoding method was developed for on-chip spectroscopy,where a PVP film embedded with Au nanorods was intimately integrated on an image sensor with a mm3 scale(Fig.1).The speckle of each signal wavelength was recorded to construct a responsive matrix for image encoding in advance.Although the image correlation is high in such a compact configuration(Fig.3),a convolutional neural network algorithm was applied to decode the image-spectrum relation by classifying the images with multilayer perceptron to extract high-level features(Fig.2).Once the calibration of image encoding is finished,the real-time spectral reconstruction takes only 1 s.Results and Discussions Spectral information was encoded in the speckle patterns generated by the Au nanorods.Conventional compressive sensing algorithm failed to reconstruct the original spectra due to the large image correlation in such a compact configuration(Fig.4).A convolution neutral network algorithm was developed to extract spectral features from low-contrast images and demonstrated accurate spectral reconstruction.For monochromatic light at 610 nm,630 nm,650 nm,670 nm,and 690 nm,the deviation of the peak wavelength is

关 键 词：显微光谱仪 图像编码 散射 深度学习 

分 类 号：TG502.33[金属学及工艺—金属切削加工及机床]