| Summary: | 碩士 === 國立成功大學 === 工程科學系碩博士班 === 100 === Due to the restriction of the diffraction limit in conventional optical microscopes, the axial and lateral spatial resolutions are hard to be achieved to a nanometer scale. Although an aperture near-field scanning optical microscope (NSOM) has been developed for breaking the diffraction limit, the spatial resolution is still limited in the range of 50 nm. To improve the current lateral spatial resolution, an apertureless near-field scanning optical microscope (aNSOM) has been developed. Furthermore, the aNSOM is applied to measure near-field fluorescence signal. The two major drawbacks of the near-field fluorescence detection which are fluorescence quenching by the metallic tip and background signals from the far-field fluorescence signal. Silicon tips and two-photon excitation allow us for quenching free detection and background suppression, respectively. In this thesis, a tip-enhanced two-photon excited fluorescence microscopy based on a commercial atomic force microscope (AFM) combined with commercially silicon tip, optical, mechanical and the FPGA module in data acquisition card of the control system has been developed to attempt to achieve a better spatial resolution. To test the performance of the system, a near-field fluorescent image from fluorescence molecules is grabbed. The interaction between the fluorescence signal and the tip is studied to assist how to obtain the fluorescent signal more efficiency. Eventually, the system could play a key role in biomolecular field, and provide fluorescence images with a molecule-scale resolution.
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