| 摘要 |
PURPOSE:To realize the rotary joint which has a hollow axis by providing a rotary body with a right-angled prism which has a through hole in the axis and coupling a rotary-side and a fixed-side optical fibers optically with each other through the prism. CONSTITUTION:The optical rotary joint consists of the fixed body 14 and rotary body 15, the right-angled prism 9 which has reflecting surfaces 9b and 9c slanting to the axis is provided to the rotary body 15, and the through hole 9a through which a cable, etc., can be run is formed in the center of the prism 9. Further, variable speed gear mechanisms 18a - 18d which rotate the prism 9 a half as fast as the rotary body 15 are provided. In such constitution, light projected from the optical fiber 11 of the fixed body side is reflected by the prism 9 and made incident on the optical fiber 13 of the rotary body side. At such a time, the prism 9 rotates at a half speed, so reflection loss is small and the axis is hollow, that a cable, etc., can be inserted. |
