Abstract: An efficient downlight system for directing light includes a light source and a generally tubular, hollow coupling device with an interior light-reflective surface for receiving light from the source at an inlet and transmitting it as a generally diverging light beam through an outlet. The coupling device is shaped in accordance with non-imaging optics and increases in cross sectional area from inlet to outlet in such manner as to reduce the angle of light reflected from the surface as it passes through the device. A thermal-isolating region has an inlet positioned in proximity to an outlet of the coupling device and has an outlet for passing light to an optical member. An arrangement for splitting the light from the outlet of the thermal-isolating region comprises a plurality of light guides. Each light guide includes an inlet end for receiving light from the thermal-isolating region and an outlet end for directing light to a remote location.

Abstract: A method of making an optical device comprises the steps of providing a body of vitreous material that is generally tubular along an axis. A portion of the body is molded with external mold structure for forming a bulbous region when the interior of the tube is pressurized. An axial portion is cut from the bulbous region to form a first coupling device with first and second axially oriented openings. This method can produce optical coupling devices with excellent optical quality in an economical manner.

Abstract: An efficient arrangement for coupling light between a light source and at least one light guide comprises a light source having a bulbous region and electrical in-leads extending into the bulbous region. A generally tubular, hollow coupling device with an interior light-reflective surface receives light from the source at an inlet and transmits it to an outlet. The coupling device increases in cross sectional area from inlet to outlet in such manner as to reduce the angle of light reflected from the surface as it passes through the device. A thermal-isolating region has an inlet positioned in proximity to an outlet of the coupling device and has an outlet for passing light to an optical member. The thermal-isolating region comprises one or more members. The foregoing can achieve high efficiency and considerable compactness while using a non-“point-like” light source.

Abstract: A light delivery system includes a light source. A first generally tubular, hollow coupling device with an interior light-reflective surface receives light from the source at an inlet and transmits it to an outlet. The coupling device increases in cross sectional area from inlet to outlet in such manner as to reduce the angle of light reflected from the surface as it passes through the device. A thermal-isolating region has an inlet positioned in proximity to an outlet of the coupling device and has an outlet for passing light to an optical member, the thermal-isolating region comprising one or more members. A waterproof container for the light source and coupling device has an aperture allowing light to pass out of the container. The aperture is sealed in part by a portion of a member of the thermal-isolating region. Advantageously, the system can be buried beneath the surface of the ground. This avoids the problem of people or equipment colliding with the system.