Abstract: A composite optical fiber is provided for permitting sensing of multiple parameters. The optical fiber is for incorporation into a sensing system, the optical fiber comprising: a single mode optical fiber core, a multimode optical fiber core, and an optical fiber cladding layer surrounding the single mode optical fiber core and the multimode optical fiber core. The optical fiber provided preferably enables multiple sensing and/or measurements to take place at a single location and at a single time.

Abstract: A composite optical fiber is provided for permitting sensing of multiple parameters. The optical fiber is for incorporation into a sensing system, the optical fiber comprising: a single mode optical fiber core, a multimode optical fiber core, and an optical fiber cladding layer surrounding the single mode optical fiber core and the multimode optical fiber core. The optical fiber provided preferably enables multiple sensing and/or measurements to take place at a single location and at a single time.

Abstract: A bulk material drilling system is described, the drilling system arranged to allow accurate directional control of a drill bit through bulk material via non-mechanical means, while providing real-time feedback on drill bit positioning. A drilling system (22) comprising; a bulk material drill bit (10) having; a sensing portion (18), one or more ports (16) for discharging output energy, the drilling system further comprising; an input portion (30) arranged to detect input parameters from the sensing portion, a controller (32) arranged to control output energy to the port; wherein the controller is further arranged to determine one or more ports to which the output energy is provided; wherein the controller is further arranged to control the discharge of the output energy; wherein the output energy discharge is non-uniformly applied to bulk material; wherein the discharge of the output energy is used to control the drill bit direction.

Abstract: An optical fiber package is described comprising a light transmitting core having a core diameter, a coating layer surrounding the core, and wherein the amount of chlorine in the light transmitting core region is homogeneous and comprises at least 3000 ppm. The fiber package is such that the optical fiber core exhibits a reduction in the hydrogen induced attenuation losses. A method for fabricating the optical fiber package is also disclosed.

Abstract: An optical fiber package is described comprising a light transmitting core having a core diameter, a coating layer surrounding the core, and wherein the amount of chlorine in the light transmitting core region is homogeneous and comprises at least 3000 ppm. The fiber package is such that the optical fiber core exhibits a reduction in the hydrogen induced attenuation losses. A method for fabricating the optical fiber package is also disclosed.

Abstract: A spacecraft or satellite optical transmission apparatus (10) including an optical fiber (11) and at least one optical pump source (14) operatively coupled to provide pump energy to the optical fiber (11), the optical fiber (11) comprising an active trivalent dopant such as erbium and at least one passive trivalent dopant such as lanthanum. A method for transmitting electromagnetic radiation in a high radiation environment is also disclosed.

Abstract: A spacecraft or satellite optical transmission apparatus (10) including an optical fiber (11) and at least one optical pump source (14) operatively coupled to provide pump energy to the optical fiber (11), the optical fiber (11) comprising an active trivalent dopant such as erbium and at least one passive trivalent dopant such as lanthanum. A method for transmitting electromagnetic radiation in a high radiation environment is also disclosed.