Abstract: The present invention provides a polishing apparatus for optical fiber end surface making it possible to freely adjust the contact pressure between a polishing plane and the distal end face of a ferrule and capable of preventing a defective product from being produced under polishing. A control circuit drives a vertically driving mechanism to allow a ferrule holding plate to move from a preparation state to a ferrule polishing starting state and by compressing a spring it then allows the ferrule holding plate to lower further beyond the starting state to complete the polishing.

Abstract: The invention provides a structure of an optical connector and an aligning method which are capable of easily accomplishing the alignment between optical fibers without pre-alignment before the assembling of the optical connector and disassembling of an optical connector assembly. A tube base fixed to a ferrule body has a plurality of fitting portions and a plurality of notch portions on its outer circumferential surface. The axial length A1 of the fitting portions is set to be shorter than the separation B between an end surface of a holder and an end surface of projecting portions of an optical connector housing. At the alignment, the ferrule body is pressed against a spring to be retreated. In this state, the fitting portions can pass in the separation B to allow the ferrule body to rotate. When releasing from the pressing against the spring, at that rotational position the ferrule body is returned by the restoring force of the spring so that the fitting portions again come into the engaged condition.