The Preparation Of Micro-hole Processed By Femtosecond Laser And Its Simulation

Femtosecond laser focus higher energy on processed areas to get to "cold" processing by inputting peal value power in super fast processing time. Femtosecond laser produce very litter thermal shock, so the plasma generated by gasification will not transfer energy to the adjacent material. Therefore the heat injury during machining process can be avoided, which can reduce energy loss and improve material's machining quality. Compared to the traditional long pulse laser, femtosecond laser have some advantages such as high precision and low energy. So it is very important to study the machining process of femtosecond laser.Firstly the characteristics and micro-machining application of femtosecond were introduced in this paper. Combining the research status of domestic and foreign, we proposed the relationship in between process parameters and material size. It is not clear to the process of machining optical fiber with femtosecond laser and there is no scholar study on field of simulate machining process. Through simulating the process, we can forecast the result of process and provide the parameters to the selection of experiment. In the third chapter, we establish proper mathematial model and compile program using Visual Basic. When changing process parameters, it will generate image automatically with VB and MATLAB. Through simulating the relationship between laser parameters and material size, we can guide the subsequent experiment and provide the basis of theory. Femtosecond laser can grate fiber and etch F-P cavity. This microstructure optical fiber sensor can improve existing sensor of machine properties and optical properties and contribute to the development of new sensors. In fourth chapter, we firstly introduced the hardware and software of the femtosecond micro-processing system and then we discussed the machining method of mirror image. Through this machining method, we can get higher quality holes. The machining method of mirror image is based on the theory of pinhole imaging. The original beam is apertured section by diaphragm, and then through the objective arrived material surfaces. Because the aperture has regular shape, so the imaging plane has distributed energy. In the coming practical processing, we only design different aperture shape and can get corresponding shape.