Abstract: Apparatus for locally abstracting light from the core of a buffer coated optical fibre, especially a buffer coated single mode optical fibre, suitable for use when monitoring the fusion splicing of optical fibres comprises a body of perspex having at least three faces, an arcuate contact face adapted to bear against a smoothly curved length of buffer coated optical fibre, an exit face through which light entering the body through the contact face can emerge and a reflecting face which will reflect light entering the body through the contact face in a direction towards the exit face. Light emerging from the smoothly curved length of buffer coated optical fibre and passing through the contact face into the body will be directed and reflected towards the exit face from where it can pass into a light detector.

Abstract: Apparatus for injecting light into the core of a buffer coated optical fibre, especially a buffer coated single mode optical fibre, suitable for use when monitoring fusion splicing of optical fibres comprises a body of perspex having at least three faces, an arcuate contact face adapted to bear against a smoothly curved length of buffer coated optical fibre, an entry face through which light emitted by a light source is injected into the body in a direction towards the contact face, and a reflecting face which reflects injected light in a direction towards the contact face. Light injected through the entry face is directed and reflected towards the smoothly curved contact face from where it will pass through the buffer coating and cladding of an optical fibre against which the body bears into the core of the optical fibre. The body is inexpensive and operates efficiently with an inexpensive light emitting source.