Illumination Technology, Inc.

John B Hartley

Ralph E Johnson

William Joseph Lang

Charles Robert Ragsdale

Muralidhar Theegala

Alexandrina Anghelus

A light bulb that is with glass envelope having light transmission of a wavelength only up to 700 nm has an incandescent filament enclosed in a glass envelope that transmits substantially no detectable amount of light of a wave length greater than 700 nanometers.

Light bulb with glass envelope having light transmission of a wavelength only up to 700 nm

A miniature or subminiature incandescent lamp designed to operate with an energy source of 20 volts or less includes a filament enclosed in a first glass envelope and supported by a pair of metal contact pins. A first glass bead seals the envelope and has a pair of openings through which the metal contact pins penetrate and wherein they are hermetically sealed. A second glass bead of low melting solder glass is larger than the first bead and is sealed below the first bead and extends circumferentially beyond the perimeter of the first bead. A third bead of high melting glass is disposed below the second bead also in sealing relationship with the second bead. The outside perimeter of the third bead is substantially co-extensive with that of the second bead. A second glass envelope is sealed to the outside perimeter of the second bead and is also in abutting relationship with the third bead. The interior of the first envelope is evacuated or contains an inert gas of the type normally used in incandescent lamps. The interior hermetically sealed space between the first and second envelopes is also evacuated, filled with an inert gas or with nitrogen. The resulting miniature and subminiature lamps have operating exterior surface temperatures which do not exceed 160&deg; C.

Low voltage incandescent lamp with dual envelope

A light bulb that is suitable for use in conjunction with night vision equipment has an incandescent filament enclosed in a glass envelope that transmits substantially no detectable amount of light of a wave length greater than 700 nanometers.

Light bulb with glass envelope having light transmission of a wavelength

A subminiature incandescent lamp has a substantially cylindrical base to which a glass envelope enclosing the interior of the lamp is sealed. A pair of contact wires or pins are made of a metal alloy that has substantially the same thermal expansion coefficient as the glass base. The contact pins are embedded and sealed to the glass base in a gas-tight manner, with a glass-to-metal seal. The contact pins extend below the base to provide external connections of the lamp to a power source. The pins also extend into the interior of the lamp, and provide electrical contact to a filament which is mounted between them. A filament support wire is anchored in the glass base at one end thereof and has a loop at its other end in which the mid-section of the filament rests and is mechanically supported.

Growing community of inventors

Pacific Palisades, CA, United States of America

John B Hartley