Abstract: An antireflection optical element formed from an optical material. The optical material includes a first plurality of antireflective surface structures in the form of first protuberances from the optical material. The first plurality of antireflective surface structures are constructed to aid in transmission of a first wavelength range through the optical material. Also included are a second plurality of antireflective surface structures in the form second protuberances from the first plurality of antireflective surface structures. The second plurality of antireflective surface structures are constructed to aid in transmission a second wavelength range through the optical material. The first wavelength range comprises longer wavelengths than the second wavelength range.

Abstract: This invention pertains to a device for broadening optical wavelength in the 2–14 ?m region comprising a light source and a highly nonlinear chalcogenide fiber associated therewith whereby a light signal is passed from the light source into the fiber wherein and through interactions between the light signal and the material, bandwidth of the light signal is broadened in the 2–14 ?m region.

Abstract: This invention pertains to a hollow core photonic band gap chalcogenide optical glass fiber and to a fabrication method for making the fiber. The fiber, which is 80-1000 microns in outside diameter, is characterized by a solid glass circumferential region and a structured region disposed centrally within the solid region, the structured region includes a hollow core of 1 micron to several hundreds of microns in diameter surrounded by a plurality of parallel hollow capillaries extending parallel to the core, the core being centrally and longitudinally located within the fiber. Ratio of open space to glass in the structured region is 30-99%. The fabrication method includes the steps of providing a mold, placing chalcogenide micro-tubes around the mold, stacking chalcogenide micro-canes around the stacked micro-tubes, fusing the micro-tubes and the micro-canes to form a preform, removing the mold and drawing the preform to obtain the fiber.

Abstract: A high-efficiency fluorescent emitter includes an excitation source and a w phonon host doped with erbium. The emitter can be used as a lasing medium or as a phosphor. Typical hosts include RcX.sub.3 and chalcogenide glasses, wherein Rc is yttrium, gadolinium, lutetium, lanthanum or a mixture thereof, and X is a halogen or a mixture of halogens.