Patent ID: 7980769

Claim:
A vacuum optical fiber connector for taking out measurement information from an inside of a vacuum device to an outside thereof with an optical fiber bundle, the vacuum optical fiber connector comprising: a first waveguide connector, to which an optical fiber bundle in the vacuum device is attached; a port flange attached to a vacuum flange of the vacuum device, the port flange housing the first waveguide connector; a second waveguide connector, to which an optical fiber bundle outside the vacuum device is attached; an attachment member fit to the port flange, the attachment member housing the second waveguide connector; and an optical transparent body: placed between the port flange and the attachment member, located entirely between the first waveguide connector and the second waveguide connector, and vacuum sealed by contact to the port flange and the attachment member through O rings, wherein the first waveguide connector and the second waveguide connector are positioned at least in two directions orthogonal to an optical axis with optical coupling of the first waveguide connector and the second waveguide connector opposed to each other with the optical transparent body between.