Abstract: An optical attenuator includes a first beam splitter for receiving an incident light beam from a light source at a predetermined angle of incidence and splitting it into a first reflected light beam and a first transmitted light beam, and a second beam splitter for receiving the first reflected light beam at the same predetermined angle of incidence and splitting it into a second refelected light beam and a second transmitted light beam. The first and second beam splitters are arranged such that the planes of incidence of the first and second beam splitters are perpendicular to each other. The optical attenuator further includes a first deflector for deflecting the first transmitted light beam to cause the deflected light to be propagated in other than the incident direction of the first transmitted light beam. A second deflector is also provided to deflect the second transmitted light beam to cause the deflected light to be propagated in other than the incident direction of the second transmitted light beam.