Research On Three-dimensional Optical Scanning Holography And Key Techniques

Optical scanning holography is different from the conventional digital holographic recording methods,the three-dimensional or multi-slice target objects are scanned by using two-dimensional lateral scanning with fixed interference fringes,this technique has strong antiinterference capability,no twin image noise,and can be used in large size object recording and fluorescence or microscopic imaging.In this dissertation,the key factors of imaging quality and related technical problems in three-dimensional optical scanning holographic imaging are systematically researched and studied.However,there are still many problems in the existing three-dimensional imaging of optical scanning holography,such as incomplete theoretical basis,low imaging quality,high noise of reconstructed image and so on,which seriously restrict the applications of optical scanning holography.The purpose of this dissertation is to solve some key issues both in principles and practical application of three-dimensional holographic imaging,such as deformation problem,and to improve the quality of three-dimensional imaging.The main research work and contributions are summarized as the following aspects:(1)Systematically analyze the parameter indexes and technical details related to the imaging quality of three-dimensional optical scanning holography,and provide the detail principles and data support.Besides,the related experimental verification is also carried out,including the selection of the best imaging region,the tradeoff of numerical aperture and resolution limit,the influence of laser Gaussian distribution,the choose of scanning interference fringes,the resolution limit,sampling rate and so on,which lay a theoretical foundation for high-resolution and high-quality optical scanning holography and its applications;(2)For the first time that optical scanning holography has different lateral magnification rate from conventional digital holography in three-dimensional imaging is found and the reasons are analyzed.The X-Y scanning mirrors has an influence at scanning interference fringes and it is analyzed,and both the related theoretical analysis and experimental verification are provided,resulted in one lateral magnification rate equation.This issue is of great significance for the application of three-dimensional optical scanning holography imaging;(3)A new reconstruction method of three-dimensional optical scanning holography is proposed.The three-dimensional or multi-section object and pinhole target are recorded by the same optical scanning holography system,and then utilize the uniqueness of recorded pinhole hologram.It firstly is filtered and pro-processed in different versions,and then these are used to reconstruct the different section object respectively.The reconstruction results can greatly improve the image quality of different section object and reduce the effect of system optical noise.Moreover,it has a better robustness property;(4)An algorithm with adaptive correction capability of nonuniformity noise on infrared focal plane arrays is proposed based on the conventional infrared holographic recording.This algorithm uses the image registration method to calculate the global displacement between the inter-frame image sequence.The overlapping regions are subsequently obtained by bidirectional registration,and then the overlapping region of the two frames in image sequence is corrected,with eliminating the ghost artifacts.It can greatly improve the effect of the nonuniformity noise correction on infrared focal plane arrays,and has strong adaptability for various dynamic scenes;(5)A novel high resolution near infrared holographic recording method is proposed for the first time.Using near infrared interference pattern fringes to excite vanadium dioxide thin film to generate photoinduced phase transition,and the visible light transmittance of vanadium dioxide thin film is changed.Then visible laser light can be used to read the near infrared interference fringes,so that the visible light CMOS device with lower pixel pitch and higher image resolution can be used to record the readout near infrared interference fringes,and the spatial resolution of the near infrared holography can be highly improved.Although the whole optical system is complicated,this method provides a new though of near-infrared holography,and improves the quality of hologram recording.