Theoretical Analysis of Laser Optics for the Rapid Prototyping

Abstract

The fabrication of three dimensional models using rapid prototyping system has been operated to make test parts not only in industry but also in medical fields in which a physical model needs to he realized from data stored in a computer. This process is paid much attention, as it is able to create a physical shape easily independent of the complexity of the model. Although the process is easier than the conventional machining, the strong demand is in the improvement of part's accuracy. The distribution of power density is one of the main factors that defines elemental unit shape of the model, and consequently it affects part's accuracy. This paper analyzes the laser optics with single and longitudinal multimodes lasers. According to this analysis, it reveals that, in the case of longitudinal multimodes laser, a difference occurs between each wave length beam waist, and the power density distribution results in the mixture of two wave length beams. This paper discusses the method to obtain the precise power distribution of a conventional system, and an optical system design is also proposed to minimize the difference of two beam waists.