Fabrication Of Microoptical Elements With Femtosecond Laser

In the domain of laser micromachining, femtosecond laser processing has attracted the scientific researcher extensively attention. In this thesis, we study the fabrication of microoptical elements with femtosecond laser. Femtosecond laser direct writing in transparent materials and the two-photon photopolymerization technology are used to fabricate the phase-gratings and Dammann grating. The main contents are classified as follows.1. The simulated annealing algorithm is used to design the Dammann grating. Many kinds of Dammann grating were designed. According to designs the result, the simulation diffraction result were present. The diffraction result proved that the result we designed have the extremely high quality, this has laid the foundation for the next work.2. We study the relations between the laser energy, the translating speed and the refractive index changed size in glass; then, the Dammann grating was fabricated inside glass by femtosecond laser amplifier successfully. According to the preliminary manufacture result, the errors were analyzed on detail.3. Researches on the two-photon photopolymerization technology by femtosecond laser oscillator were processed. The relations between the feature size and the exposure time, the laser power, the processing speed were researched firstly, after that, we fabricated the phase grating and unidimensional Dammann grating. Through adjustment the thickness of the photoresist, the better manufacture result was obtained. The result has shown that the two-photon photopolymerization technology has the extremely good prospect in the manufacture of microoptical elements domain.