An optical receptacle includes a fiber stub, a block, and a first elastic member. The fiber stub includes an optical fiber, and a ferrule provided on one end side of the optical fiber. The block is separated from the ferrule and has one end surface, an other end surface, and a through-hole extending from the one end surface to the other end surface. A portion of the optical fiber protrudes from the ferrule and is inserted into the through-hole. The first elastic member fixes the optical fiber in the through-hole. The portion of the optical fiber includes first to third portions. The second portion is provided between the first portion and the third portion. A core diameter at the first portion is smaller than a core diameter at the third portion. A core diameter at the second portion increases from the first portion toward the third portion.

A spot size converter includes a first waveguide including a first core layer, the first waveguide propagating light; and a second waveguide including a second core layer and provided on the first waveguide, the second waveguide propagating light. The first waveguide and the second waveguide extend in a waveguide direction. A first region and a second region are provided continuously along the waveguide direction. In the first region, the second waveguide has a tapered shape in a cross section which becomes narrower as going up away from the first waveguide. An angle between a side surface of the second waveguide and a bottom surface of the second waveguide is 60 or less.

An epoxy-free, high-durability and low-cost plastic optical fiber splice design and fabrication process which meets commercial airplane environmental requirements. The splice design: (1) does not require the use of epoxy to join the end faces of two plastic optical fibers together; (2) incorporates double-crimp rings to provide highly durable pull force for the plastic optical fibers that are joined together; (3) resolves any vibration problem at the plastic optical fiber end faces using a miniature stop inside a splice alignment sleeve; and (4) incorporates a splice alignment sleeve that can be mass produced using precision molding or three-dimensional printing processes.

An integrally molded multi-optical transmission sheet includes: a sheet-like coated portion formed of plastic; and a plurality of optical transmission regions having a core region formed of plastic, and a clad region formed of plastic and surrounding an outer periphery of the core region, which are provided inside the coated portion to extend along an extending direction of the coated portion, wherein the plurality of optical transmission regions are arranged in a row substantially parallel to each other along a main surface of the coated portion, and in a case where light is incident from one end face side of the plurality of optical transmission regions and transmitted toward the other end face side, a M.sup.2 value of emitted light is 1.7 or more.

A surgical lead is provided which includes a generally flexible polymeric panel incorporating a set of electrode arrays embedded in one side. The electrode arrays are connected to integrally formed leads which house conductors that connect the electrodes to a set of contacts. The contacts engage an IPG header. The leads incorporate an optical fiber which extends from the IPG header to a set of window portals in the flexible panel. Each of the fibers includes a side firing section adjacent the optical windows for transmission or reception of light. Optimally placed reflectors and heat shields are also provided.

An implantable pulse generator is provided comprising a non-metallic shell adjacent a header. The header abuts an optical window in the shell. The header aligns a series of surgical or percutaneous leads with the optical window. The leads incorporate optical fibers, electrodes and contacts which distribute stimulation signals. Behind the optical window, a set of optical devices is provided which transmit or receive light from the fibers. Signal processors are provided to interpret the signals from the optical fibers, and to mitigate a continuous inductive charging function.

A percutaneous lead is provided which includes a generally tubular, multi-duct, flexible lead body. The lead body supports a distal set of electrodes and a proximal set of contacts which are connected by conductors in the ducts. The lead body further houses an optical fiber with a side firing section. The side firing section is held adjacent an optical transmission window, integrally formed with the flexible lead body. A cylindrical ferrule is provided to position the fiber in the header of an IPG.

A method of making a transverse Anderson localization (TAL) element includes mixing pellets together to make a mixture, the pellets being of two or more distinct materials having respective wave speeds effective to provide Anderson guiding. The mixture is fused to make a preform which has respective pellet-size areas of the distinct materials corresponding to the pellets in the mixture. One or more stretching operations is performed to stretch the preform into the TAL element.

An optical fiber cable comprising an optical fiber, and a jacketing layer including at least two or more layers of a jacketing inner layer and a jacketing outer layer formed in this order concentrically, wherein the jacketing layer comprises at least two or more layers of a jacketing inner layer and a jacketing outer layer formed in this order concentrically; a material constituting the jacketing inner layer is composed of a resin material having an oxygen permeability of 2.0 cc.Math.20 m/(m.sup.2.Math.day.Math.atm) or less; a material constituting the jacketing outer layer comprises at least one selected from a polyolefin-based resin, a polybutylene terephthalate-based resin, and a fluorine-based resin containing no chlorine atom in its structure; and the following general formula (i) and (ii) are satisfied when an outer diameter of the optical fiber is denoted by A (m), an outer diameter of the optical fiber cable is denoted by B (m), and a thickness of the jacketing outer layer is denoted by c (m):

900A1100(i)

0.402c/(BA)0.70(ii).

A plastic optical fiber is excellent in translucency, heat resistance, resistance to environment and the like, and has highly excellent flexibility. The plastic optical fiber contains a core and at least one layer of cladding, wherein the bending elastic modulus of the innermost layer of the cladding is 20 to 70 MPa, the glass transition temperature of the innermost layer of the cladding is 10 C. or lower, and the storage elastic modulus of the innermost layer of the cladding at 30 C. is 110.sup.6 Pa to 410.sup.7 Pa.