Abstract:
A flat glow discharge lamp includes a discharge tube having two opposing flat faces and a first and second plurality of long electrodes disposed on respective opposing flat faces, wherein one of the pluralities of long electrodes is composed of a transparent conductive material. The discharge lamp includes a fluorescent layer disposed on the inner surface of the discharge tube, and either rare gases, such as argon, or low-pressure mercury vapor. The first and second plurality of long electrodes provides for a homogeneous discharge over the face of the discharge lamp.
Abstract:
A negative glow discharge lamp having improved color stability and increased life includes a light-transmitting envelope which contains an ionizable medium including mercury and a gaseous fill. The gaseous fill includes neon and a predetermined amount of krypton. The krypton is in an amount equal to less than five percent of the gaseous fill.
Abstract:
A fluorescent low pressure discharge lamp is provided with a sintered electrode consisting of about 50% to 90% by weight of W and the remainder BaO or a mixture of BaO, CaO and SrO and an oxide of Y, Zr, Hf or an oxide of the rare earths.
Abstract:
The invention relates to electrode mount assemblies for electric discharge and fluorescent lamps. In accordance with the first aspect of the invention the portions of the electrode support wires which are exposed to electron bombardment within the body of the lamp have at least their surface formed of refractory material. The exposed portions may be coated with a refractory material such as boron nitride or made wholly of a refractory metal such as molybdenum. According to a second aspect of the invention relatively cheap soda-lime silicate glass can be used for the end flares of the lamp tubes, because the provision of refractory surfaces on the vulnerable portions of the support wires enables a metal to be chosen for the portions of the wires passing through the glass seal which closely matches the glass in thermal expansion coefficient. The invention improves the life of lamps by reducing end blackening, reduces the incidence of cracks in the punch seal or neck regions of the lamp and may enable cheaper materials to be used for various structural items.
Abstract:
A short arc fluorescent lamp comprises an envelope having dimensions compatible with existing incandescent lamp luminaires. A radio frequency power supply, enclosed within the lamp base structure, reduces anode voltage drop to increase lamp efficacy. Cathode voltage drop and sputtering are reduced by compact hollow cathode assemblies, including centrally disposed filaments, which are positioned at opposite ends of a tubular envelope assembly having a large ratio of diameter to length. Diffuse cathode emission allows operation with low pressure, low atomic weight fill gas which further increases luminous efficiency.
Abstract:
An emissive electrode of the type utilized in fluorescent lamps and a method for making such an electrode. The electrode includes a fused cylindrical pellet and two metal leads, a portion of one of said leads extending within one end of said pellet and a portion of the other of said leads extending within the opposite end of the pellet. The pellet contains a fused mixture of electron emissive material and a metal having a high melting point and a low vapor pressure, and it has a bulk density gradient structure. The heat necessary to cause thermionic electron emission from said electrode is provided by current passing through the pellet structure separating said leads when a voltage is applied across said leads. The pellet is formed by mixing a powder of said metal with a powder of said electron emissive material, adhering said powder particles one to the other, and heating said mixed powder in a mold until an exothermic reaction occurs.