IRRADIATOR FOR IRRADIATING INNER SURFACE OF TUBULAR OBJECT

摘要

A probe (10) for inspecting the inner surface of a tube (40) utilises a group of large diameter optical fibres (12) as a light source and an annular ring (14) of smaller diameter optical fibres as interceptors of the reflected light. A pair of plano-convex lenses (16) focuses a light beam (42) emanating from the group of large diameter optical fibres (12) onto a reflective ball bearing (18) or a concave cone (32) causing a circumferential band (44) to be illuminated on the inner surface of the tube (40). Light from the band (44) is intercepted by the optical fibres within the annular ring (14) and is transmitted therethrough. The transfer of light from the band (44) to the annular ring (14) can be optimised by bevelling the end of the optical fibres (14) within the annular ring.