Study On Scene Fusion And Scaling In Digital Holographic Dynamic Three Dimensional Display

Holographic 3d display technology can reproduce the amplitude and phase information of object light wave completely.With the rapid development of computer technology and optoelectronic imaging devices,the traditional optical holography can be digitized.In recent years,virtual reality(VR)and augmented reality(AR)have become the focus of people’s research.In holographic display,many hybrid scene display schemes based on digital holographic recording of real objects and computational holographic generation of virtual objects have been put forward,which have achieved good display effects,but mostly remain in static display.According to the demand of real-time dynamic display in VR and AR,this paper studies the fusion and scaling method of virtual and real scenes in digital holographic real-time dynamic 3d display.The optical reconstruction system was built and the holographic dynamic 3d display of mixed scenes is verified.The main contents of this paper are as follows :(1)the development of various 3d display technologies is summarized,and the research background of digital holographic display is mainly introduced.(2)the basic theory of digital holography is introduced.(3)the problem of digital holographic scene fusion is analyzed.A hologram fusion method is proposed to realize scene fusion for real-time dynamic holographic 3d display.The problems of sampling rate transformation and diffraction efficiency improvement in hologram fusion are analyzed.It is concluded that the diffraction efficiency of the fused hologram can be effectively improved by applying high-pass filtering to the digital hologram,filtering the zero-order term and then adding it to the computed hologram withbipolar strength calculation.(4)the reproduction image scaling problem in real-time dynamic holographic 3d display is studied.Two digital scaling methods based on spatial processing and frequency processing are proposed,both of which do not reduce the parallax Angle of the hologram,and the method based on frequency processing of the hologram can realize the scaling and translation of the reconstructed image of the specified object in the information recorded by the original hologram.(5)an optical reproduction system with three LCOS as the core is built to verify the correctness of the proposed method,and the color dynamic 3d display of mixed scene is preliminarily realized.Paper innovation points are mainly:(1)the proposed filtering processing of digital hologram first filter zero order item,again with a bipolar strength calculation of hologram superposition method to implement digital hologram fusion,so as to improve the diffraction efficiency of hologram,reach and integration scenarios taken directly or computing hologram diffraction efficiency of the same.(2)two digital scaling methods based on hologram spatial processing and frequency domain processing without changing hologram perspective are proposed to achieve rapid scaling of reconstructed image.