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In many laser processing applications ultrashort pulse laser have certain advantages, relative to picosecond and longer laser pulses. Many applications of femtosecond (fs) laser in precision micro-processing and micro-structuring of a wide variety of materials including transparent dielectrics, semiconductors, and metals have been demonstrated. In this dissertation, several preliminary results of fs laser induced microstructures both in the interior and on the surface for some materials of glasses,crystals and metal films have been achieved. These researches can be split into three parts.1. Fs laser induced refractive index change and optical functional microstrctures inside transparent materials, fluoride crystals, scintillating crystals and noble metal ions-doped silicate and phosphate glasses(1) Fabrication of microstructures inside crystal materialsFabrication of internal diffraction gratings in LiF, CaF2 and GSO:Ce crystals by a focused fs laser was demonstrated. The temperature-dependence of fs laser induced refractive index change in these crystals indicates that the formation of color centers and the permanent structural changes contribute to the refractive index change.Controllable refractive index change can be achieved by adjusting fs laser irradiation parameters and subsequent annealing conditions. By this way, one can induce refractive index change for these crystals to fabricate internal diffraction grating or optical waveguide, etc. for three-dimensional integrated optical devices. In addition,the overlapped gratings were fabricated in GSO:Ce crystal by taking advantage of the birefringence of fs laser beam in anisotropic materials.(2) Mechanisms of the refractive index change in the Au<3+>-doped silicate glassesThe mechanisms of the refractive index change in the Au<3+>-doped silicate glasses by irradiation of the fs laser and further heat treatment at various temperatures are clarified. The formation of color centers and the precipitation of gold nanoparticles contributed to the refractive index change, and the structural change such as local densification, only played a little role in the present silicate glass system. Controllable refractive index change could be achieved by fs laser induced formation of color centers and precipitation of gold nanoparticles. We can induce refractive index change with no or less structural dislocation in materials, which is important for fabrication photonic devices with fine structures.(3) Manipulation of silver nanoparticles in Ag<+>-doped phosphate glassesA controllable process of precipitation and dissolution of silver nanoparticles in fs laser irradiated Ag<+>-doped phosphate glass are demonstrated. A mechanism that combines the formation and decoloration of color centers, precipitation and dissolution of silver nanoparticles in ultrafast laser pulses irradiated Ag<+>-doped phosphate glass is discussed. The process can be controlled by adjusting the laser irradiation parameters and annealing parameters.2. Preparation of diffractive optical elementsDirect writing computer generated-holograms on metal film by fs laser is demonstrated. Computer generated-holograms have been fabricated on metal film by fs laser point-by-point writing. The computer generated-hologram can work as both transmission and reflection modes. The fabrication process requires no mask, no preor post-treatment of the substrate.3. Formation of periodic microstructures by multi-beam interference of fs laser pulsesThe fabrication of periodic microstructures by multi-beam interfering fs laser pulses is presented. The formation of micrometer order periodic structures on silicon wafer, metal film and metal foil was achieved by direct five-beam fs laser interference.In addition, a new technique of transfer of periodic microstructures of metal film from a supporting substrate to a receivingsubstrate has been developed. By adjusting laser energy, angle of the beams, focal length, irradiation time, laser wavelength, etc. the fabricated structures can be changed in period and shape. The present technique allows one-step, large-area, micrometer processing of materials for potential industrial applications.