Abstract: There is described an optical fiber coupler in which at least one fiber is a multiple-clad fiber, containing a single-mode core supporting a single guiding mode and an inner multi-mode cladding guiding multiple modes. The multiple-clad fiber is fused with a second fiber of a different etendue to create an optical fiber coupler having an enhanced multi-mode signal transmission.

Abstract: The biopsy device generally comprises: a cannula body having a longitudinal axis and a probing region extending along the longitudinal axis, the probing region having a sample receiving window defined therein for receiving a sample of a surrounding tissue when performing a biopsy; and a plurality of optical fibers mounted along an exterior portion of the cannula body, each of the plurality of optical fibers having a fiber end in the probing region of the cannula body, at least one of the plurality of optical fibers being adapted to illuminate the surrounding tissue with an optical signal generated by the at least one light generator and at least one of the plurality of optical fibers being adapted to detect an optical signal response with the at least one light detector, the optical signal response being caused by the propagation of the optical signal in the surrounding tissue.

Abstract: There is described an optical fiber coupler in which at least one fiber is a multiple-clad fiber, containing a single-mode core supporting a single guiding mode and an inner multi-mode cladding guiding multiple modes. The multiple-clad fiber is fused with a second fiber of a different etendue to create an optical fiber coupler having an enhanced multi-mode signal transmission.