| Recent years, the ultra-broadband optical parametric amplification of image andthe corresponding fields are the projects of international advanced scale and therehave focused more people’s attention. The coherence white continuum imaging isrealized by the ultra-broadband optical parametric amplification of image; the opticaltemporal gating and the exposure speed of the ultra-speed imaging can up to the levelof femto-second while using the femto-second laser as the source of imaging, whichcan be used to the ultra-speed temporal resolved imaging of through highly scatteringmedia, ultra-speed fluorescence dynamics and the imaging of fluorescence lifetimeand so on. The quantum imaging of super-limitation of quantum noise is achieved viathe noiseless optical parametric amplification of image. Furthermore, the opticalparametric amplification of image can be also applied in the fields of thesynchronization of high accuracy time, the accuracy spatial location, the micro-imageenhancement of super-resolved3-D, and high speed imaging and so on. In this thesis,the ultra-broadband phase-sensitive optical parametric amplification of image in aBBO nonlinear crystal with type I phase-matching are numerically simulated andanalyzed. Furthermore the generation of the super-continuum is studiedexperimentally. The mainly contents are concluded as following:1. The basic analysis: By the Maxwell’ equations, the three waves couplingequations are derived. The analytical solution of un-depleted pump and thenumerical solution of high gain are represented. The effects of the phase matching,the group velocity matching, and the walk-off in parametric process based onBBO nonlinear crystal are discussed in detail. The relations of input-output of theoptical image in Fourier domain and space domain are derived from opticaltransfer function. At the last, the phase sensitive gain and the phase insensitivegain are discussed detailedly.2. The ultra-broadband optical parametric amplification based on the prior chirpedcontrol: A the first, the type-I collinear phase matching of broadband pump inBBO nonlinear crystal is represented. The delay time between the zero dispersion wavelength and the wings of the continuum is calculated by modeling the curve ofthe dispersion in photonics crystal fiber (PCF). Therefore, the pulse duration ofthe chirped pump is obtained which is required in the parametric process. Bytuning the delay time of the chirped pump, the every components of the pump issynchronous with the components of the signal which satisfy the condition of thephase matching. Finally, the ultra-broadband optical parametric amplification isrealized.3. The simulation of ultra-broadband optical parametric amplification of image: Apseudo color image imprinted a “plane” is used as the input image. By recording aseries of monochromatic image, and inserting into the RGB table, the amplifiedpseudo color image is obtained, and the gain is displayed by the3-D image. Inorder to observe the resolution of the amplified polychromatic image, a pseudocolor letter pattern and a resolved pattern are used as the input images. The effectsof the initial phase of the input image and the mismatching in the broadband phasesensitive amplification and de-amplification are numerically simulated andanalyzed. At the last, the resolution of the ultra-broadband optical parametricamplification of image is calculated by estimating the spatial frequency bandwidthof the amplifier and by the inverse Fourier transform of the optical transferfunction (OTF) of the phase sensitive amplification, respectively. The resultsbased on the different ways are almost equal, which are close to the classicaldiffraction limit.4. The experimental investigation of the super-continuum: The fundamental laser isgenerated in an Yb-doped fiber amplifier pumped by semiconductor laser at976nm. The fundamental laser is lunched into the photonic crystal fiber (PCF) togenerate the super-continuum by fusing the output end of the fundamental laserwith the tail fiber of the PCF. |
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