| Holographic technology has been widely concerned, because it can simultaneously show amplitude and phase information of three-dimensional objects. With the appearance of spatial light modulator (SLM) and CCD (or CMOS) as the image sensor, the incoherent digital holographic technology has been rapid development, which overcomes two problems at the coherence limitation and inseparable twin image in the conventional optical holography. It has proposed a number of different spectroscopic methods of the incoherent digital holography, such as triangular holographic interferometer, Michelson interferometer, a Mach-Zehnder interferometer etc, according to the recording mode of the hologram. Joseph first proposed a incoherent on-axis digital holography in 2007 (namely Fresnel Incoherent Correlation Holography, FINCH) based on SLM.FINCH system is characteristic of a incoherent on-axis interferometer as the core, which is composed of SLM and CCD. SLM has the function of split beam and phase shift. CCD has been used to record holograms. This system has the advantages of simple operation, recording speed, without scanning the object in either space or in time. The biggest advantage of the FINCH system is that it can be matched with any standard optical imaging technology, which can realize microscopy imaging, telescopic imaging and spectroscopic imaging etc based on incoherent digital holographic, and has important application prospect in remote sensing, astronomy, microscopy, material analysis.In the first chapter, the recording and reconstruction principle of the traditional optical holography and digital holography are introduced.The second chapter, we mainly introduce the principle and classification of spatial light modulator, and the application of SLM in laser digital holography and on-axial incoherent digital holography.The third chapter, we mainly introduce the recording and reconstruction principle of the Fresnel incoherent correlation holography system, deduce the system point spread function, transverse magnification, reconstructed distance and other parameters from the perspective of wave optics, analog reconstruction of collimating lens distance different from three-letter "Z" and "W" or "F" reconstruction based on Fresnel incoherent correlation holography system, and verified theoretically imaging characteristic of Fresnel incoherent correlation holography system.The fourth chapter, we mainly discuss the imaging characteristics of Fresnel incoherent correlation holography system:the reconstruction images of the resolution plate and the real dice are given, which have verified experimentally that Fresnel incoherent correlation holography system can realize the true reconstruction of a three dimensional object. The questions of the imaging quality of FINCH system have been discussed from the following aspects. First, using the polarization characteristics of SLM, there is an discussion whether or not the polarizer has an effect on reconstruction image background noise through compared experiment; second, through the comparison of the optical path difference, the reason of the difference between the quality of the reconstructed image is analyzed, when SLM loading single-lens and dual-lens models; third, by changing the phase multiplexing mode of SLM, the effects of different phase masks on the quality of the reconstructed image are analyzed.The fifth chapter, we mainly discuss the feasibility of Fresnel incoherent correlation holography for spectral imaging, the parameters of the point spread function, the transverse magnification and the reconstructed distance of the system are analyzed, it is concluded that both the lateral magnification and the reconstructed distance are functions of the imaging wavelength, by imaging the resolution plate and dice, the imaging properties of the system are has been verified.The last part of the paper is a summary of the full text. |
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