Abstract
ODV (OmniDirectional Vision) is an optical system which has the view angle more than 180° with little distortion. If this ODV can be made smaller than now, various applications for medical and/or industrial fields will be expected. The optical system of ODV for side view is composed of a primary mirror and a secondary mirror. Therefore, the machining method for making these small mirrors was investigated.
At first, the occurrence of interference fringes and the decrease in resolving power due to tool marks were examined. The experimental analysis made it clear that it was necessary to reduce the tool marks per unit length in order to decrease the interference fringes, while the tool marks hardly affected the resolving power . The reflect side of the mirror has the thin part because of the mounting space for CCD camera. Therefore, the cutting test of thin part in simple model was carried out. It was found that the distortion didn't occur in the reflected image as long as the flatness was less than about 150nm. Then, the ring-shaped jig was used for holding the mirrors, since these structures were very small and flexible. It was confirmed that the accuracy of mirrors cut with using this jig was within the permissible range. As a result, the making method of high precision mirrors for small size ODV was established in this study.