Design Of Far Infrared Light Field Imaging System And 3D Reconstruction

As one of the research directions of computational photography,light field imaging can obtain four-dimensional plenoptic information of the target by improving the traditional imaging system and processing with computer software algorithm.The acquisition of plenoptic information increases the dimensionality of information collecting,overcomes many limitations of traditional optical imaging,and can realize applications such as refocusing imaging,all-focusing imaging,synthetic-aperture imaging,and three-dimensional imaging.At present,light field imaging is concentrated in the field of visible light,and applications in other wavelength bands are relatively rare.The band of 8-12um is called far infrared band.Since the radiation emitted by human body is within this range,it is also called thermal imaging band.It had important applications in the military and industry.This paper combines the light field imaging system with the far infrared imaging system.Starting from the principle of light field imaging and the characteristics of infrared imaging,we seriously study the structure design of the infrared light field imaging system.According to the focused light field image obtained by the designed far infrared light field imaging system,the depth estimation algorithm and three-dimensional reconstruction method of the focused light field camera are further studied.The specific research contents are as follows:(1)Studying the structure design method of focused light field imaging system.Combining with the analysis of depth resolution,we propose a system structure design method to obtain the best imaging conditions.Based on this design method,a far infrared light field imaging system is designed.The simulated light field image is obtained through the Zemax bitmap image simulation.Next,the two-dimensional sub-aperture image is rendered using the traditional focused light field image rendering algorithm.(2)We build the far infrared light field imaging system based on the pinhole array.Through the adjustment of the system structure,it breaks through the many limitations of far infrared imaging,obtains the far infrared light field image,and verifies the feasibility of the combination of the two systems and the validity of the theoretical design.(3)We design and build the far infrared light field imaging system based on the infrared microlens.And we simulate the infrared microlens array by using the single infrared microlens with the precision electric sliding table.Through the light field imaging system,we obtain far infrared light field images in a real scene and two-dimensional sub-aperture images of infrared light field images by using the rendering algorithm.(4)We research and implement the depth estimation algorithm of the focused light field imaging system.Through the obtained original light field disparity map,the focused light field rendering algorithm is used to calculate the original light field sub-aperture map and its disparity map.Therefore,the depth of the original scene is obtained.The three-dimensional surface structure of the scene is reconstructed by combining with point cloud reconstruction.Through simulations and experiments,this paper proves that the far infrared light field imaging system can passively acquire the depth information of the infrared scene and greatly enhance the application prospects of the infrared system.