| With the increasing demand of infrared imaging technology,the application of infrared imaging technology is limited due to the cost and technological level.In order to realize the imaging of weak infrared radiation,save the cost and improve the detail resolution of imaging,a method of combining optical tomography technology with frequency modulation disk imaging technology is proposed to realize an imaging system with higher resolution and high signal-to-noise ratio at low cost.The experimental results show that the technology can ensure the stability of the imaging even if the infrared focal plane array can not image.The main research work and achievements of this thesis include:1.Based on the Fourier central slice theorem in tomography,the imaging principle of frequency modulation disk is deeply studied.It is proposed that the projection information of each angle can be modulated by frequency modulation disk,and the signal-to-noise ratio of the whole system can be greatly improved by means of spatial filtering characteristics of modulation disk.2.Build the hardware system of tomography,which is composed of the precise bezhan prism group,high-precision turntable,cylindrical mirror and other optical elements,design the optical path of the imaging system,and use the optical simulation software to simulate the optical path.The simulation results show that the optical path designed in this experiment can fully meet the experimental requirements.3.A new data processing scheme is proposed to solve the problem of slow reconstruction speed of serial image reconstruction algorithm.By analyzing the characteristics of filtered back projection algorithm,a parallel data processing program based on GPU is designed.Compared with the traditional serial reconstruction program,this program can improve the reconstruction speed by more than 10 times. |
