Nano accuracy elevation of ultra-precision machining using optical fiber laser encoder system

Abstract

The ultra-precision products which recently experienced high in demands had included the large areas of most updated technologies, for example, the semiconductor, the computer, the aerospace, the media information, the precision machining. For early 21st century, it was expected that the ultra-precision technologies would be distributed more throughout the market and required securing more nation-wise advancements. Furthermore, there seemed to be increasing in demand of the single crystal diamond tool which was capable of the ultra-precision machining for parts requiring a high degree of complicated details which were more than just simple wrapping and policing. Moreover, the highest degree of precision is currently at 50 nm for some precision parts but not in all. The machining system and technology should be at very high performed level in order to accomplish this degree of the ultra-precision. It was known that the products requiring the ultra-precision machining technology were applied only in some advance countries until 10 year ago as measuring instrument, satellite observing systems, airplane observing system, and national defense weapon system and other special areas which all included precision optics. In 70s, the aspheric lens were required their presence in limited areas, thus the products were manufactured individually by experienced engineers. However, there were increasing demands in the aspheric optic technology since there were dynamic developments in the electronics and the optics and increasing preferences in lightweight. There should be the improvement in machining technology since the degree of precision in the aspheric lens increased as the optical wavelength had shortened. The technological manipulation of the piezo electric actuator could compensate for the errors of the machining precision during the process of machining which lead to an elevation and enhancement in overall precisions. This manipulation is a very convenient method to advance the precision for nations without the solid knowledge of the ultra-precision machining technology. Moreover, there is an increasing demand of the highly responsive ultra precision positioning control technology based on the piezo electric actuator for the non-axis symmetrical mirror machining as well as the delicate control of infeed rate application such as the ductile mode machining of the hardened-brittle materials. Due to the facts mentioned above, the ultra precision positioning technology being manipulated by the piezo electric actuator was regarded as the basis of this investigation.