Abstract
Mold of micro lens array can be finished with indentation tools that indent and transcribe lens cavities. In the process, ultrasonic vibration applied on tools can improve surface roughness of the cavities. This process requires establishment of rational design of ultrasonic tools. Then, the design method based on FEM analyses are examined for round bar cantilever tools. Since vibration modes and natural frequencies are theoretically determined corresponding with diameter and length of tool, the effects of change in length and diameter on vibration characteristics are examined with FEM analysis. The tool shape for aimed vibration mode can be determined from the natural frequency distributions and additional analysis based on bisection method. The rational design is proposed with description of the algorithm.
