Optical power meter

Claim 1

Portable apparatus for measuring the optical power of optical energy passing along an optical fibre, the apparatus comprising tapping means for tapping optical radiation from the optical fibre, a transducer for converting the tapped optical radiation into an electrical signal, and display means for providing an indication of the magnitude of the electrical signal, said magnitude being indicative of the optical power carried by the fibre, the tapping means comprising a pick-up element defining a curved optical waveguiding path, and clamping means for clamping the optical fibre with sufficient force to retain the optical fibre in a curved position which at least substantially conforms to the inner side of the curved path, such that in use optical energy passing along the optical fibre is coupled into the curved optical waveguiding path, wherein the curved optical waveguiding path has a minimum radius of curvature chosen such that measurement of the optical power of optical energy passing along the fibre can be performed without causing an attenuation of said optical energy of more than 3.5 dB.