Abstract: A ceramic discharge chamber for a lamp, according to an exemplary embodiment of the invention, comprises a first member which includes a leg portion and a transition portion, wherein the leg portion and the transition portion are integrally formed as one piece from a ceramic material, and a second member which includes a body portion, wherein the body portion is bonded to the transition portion of the first member. The ceramic discharge chamber can be formed by injection molding a ceramic material to form the first member, the first member forming a first portion of the ceramic discharge chamber; and bonding the first member to a second member which forms a second portion of the ceramic discharge chamber.

Abstract: A discharge chamber for a lamp, the discharge chamber comprising a monolithic ceramic article having a main body defining an arc chamber and generally opposed leg members defining openings which may accommodate an electrode or electrode lead through. A method of making a ceramic discharge chamber comprising the steps of forming a mixture comprised of ceramic powder and a binder and injecting the mixture into a die and around a mold to form at least a main body of the discharge chamber.

Abstract: A ceramic discharge chamber for a lamp, according to an exemplary embodiment of the invention, comprises a first member which includes a leg portion and a transition portion, wherein the leg portion and the transition portion are integrally formed as one piece from a ceramic material, and a second member which includes a body portion, wherein the body portion is bonded to the transition portion of the first member. The ceramic discharge chamber can be formed by injection molding a ceramic material to form the first member, the first member forming a first portion of the ceramic discharge chamber; and bonding the first member to a second member which forms a second portion of the ceramic discharge chamber. The members which form the ceramic discharge chamber can greatly facilitate assembly of the discharge chamber, because the discharge chamber can be constructed with only one or two bonds between the members.

Abstract: A ceramic discharge chamber for a lamp, according to an exemplary embodiment of the invention, comprises a first member which includes a leg portion and a transition portion, wherein the leg portion and the transition portion are integrally formed as one piece from a ceramic material, and a second member which includes a body portion, wherein the body portion is bonded to the transition portion of the first member. The ceramic discharge chamber can be formed by injection molding a ceramic material to form the first member, the first member forming a first portion of the ceramic discharge chamber; and bonding the first member to a second member which forms a second portion of the ceramic discharge chamber. The members which form the ceramic discharge chamber can greatly facilitate assembly of the discharge chamber, because the discharge chamber can be constructed with only one or two bonds between the members.

Abstract: A discharge chamber for a lamp, the discharge chamber comprising a monolithic ceramic article having a main body defining an arc chamber and generally opposed leg members defining openings which may accommodate an electrode or electrode lead through. A method of making a ceramic discharge chamber comprising the steps of forming a mixture comprised of ceramic powder and a binder and injecting said mixture into a die and around a mold to form at least a main body of said discharge chamber.

Abstract: An electric lamp (100) including a sealed light-transmissive lamp envelope (105) having an interior space, a base fixed to the outer envelope (105), a non-insulated main conductor wire (160) within the outer envelope and connected to the base (110) at one end, a light source (140) capable of generating light within the outer envelope (105), a shroud (145) surrounding the light source (140) and mounted adjacent the non-insulated main conductor wire (160), and a first center support. The light source (140) has first and second ends. The first end is electrically coupled to the non-insulated main conductor wire (160), and the second end is coupled to a stem lead (180). The first center support (150) supports the shroud (145) and the light source (140) and mechanically couples the shroud (145) and the light source (140) to the non-insulated main conductor wire (160).

Abstract: A method of making a component of a ceramic discharge chamber comprising the steps of forming a ceramic composition including an aluminum powder, a binder and a grain growth inhibitor. The alumina powder has a tap density greater than 1.0 gram per cc. The ceramic composition is then die pressed to form a component preform. Next, the component preform is heated to remove at least a substantial portion of the binder.

Abstract: An arc discharge vessel having electrodes disposed therein, a fill within the discharge vessel wherein the arc discharge vessel is comprised of alumina including the following dopants in parts per million: 50≦MgO≦1500; 100≦HFO2 ≦1500; 0≦ZrO2≦700; 0≦Y2O3≦300; 0≦Sc2O3≦1000; 0≦Dy2O3≦1000; 0≦Tb2O3≦1000; with the proviso that at least 5 ppm Y2O3, Sc2O3, Dy2O3, Tb2O3, or mixtures thereof is included.

Abstract: A ceramic discharge chamber for a lamp, according to an exemplary embodiment of the invention, comprises a first member which includes a leg portion and a transition portion, wherein the leg portion and the transition portion are integrally formed as one piece from a ceramic material, and a second member which includes a body portion, wherein the body portion is bonded to the transition portion of the first member. The ceramic discharge chamber can be formed by injection molding a ceramic material to form the first member, the first member forming a first portion of the ceramic discharge chamber; and bonding the first member to a second member which forms a second portion of the ceramic discharge chamber. The members which form the ceramic discharge chamber can greatly facilitate assembly of the discharge chamber, because the discharge chamber can be constructed with only one or two bonds between the members.

Abstract: A method of making a ceramic discharge chamber comprising forming a plurality of preform chambers by assembling at least two ceramic components. The preform chambers are axially aligned within a tube, comprised of an alumina cermet. The tube containing the preform chambers is then fired at a temperature of at least 900° C.

Abstract: A ceramic discharge chamber for a lamp, according to an exemplary embodiment of the invention, comprises a first member which includes a leg portion and a transition portion, wherein the leg portion and the transition portion are integrally formed as one piece from a ceramic material, and a second member which includes a body portion, wherein the body portion is bonded to the transition portion of the first member. The ceramic discharge chamber can be formed by injection molding a ceramic material to form the first member, the first member forming a first portion of the ceramic discharge chamber; and bonding the first member to a second member which forms a second portion of the ceramic discharge chamber. The members which form the ceramic discharge chamber can greatly facilitate assembly of the discharge chamber, because the discharge chamber can be constructed with only one or two bonds between the members.

Abstract: An arc discharge lamp comprising an arc tube including a starting aid is provided. The starting aid comprises at least one prealloyed powder bound to the surface of the arc tube.

Abstract: An arc discharge lamp comprising an arc tube including a starting aid is described. The starting aid comprises at least one metal cermet coating applied to the surface of the arc tube, or a metal layer including refractory glass disposed over said cermet coating or said metal layer.

Abstract: An arc discharge lamp, such as a metal halide arc discharge lamp, has an extended life by reducing loss of the metallic portion of the fill. At least one component of the fill reacts with fused silica in the arc tube or diffuses through the arc tube walls. The fill will generally comprise a sodium halide, at least one additional metal halide, and an inert starting gas. A borosilicate glaze which is vitreous and light-transmissive is provided on the wall of the arc tube. The borosilicate glaze is comprised of a borosilicate glass containing at least one metal oxide selected from aluminum, scandium, yttrium, and the rare earth elements. The borosilicate glaze may further contain additional rare earth elements or transition metals to alter the light or energy emission of the lamp by absorbing select wave lengths. For instance, titanium, ceria, cobalt, chromium, iron or neodymium, or combinations of the foregoing, may be added.

Abstract: A process for converting a polycrystalline ceramic material to a single crystal material includes the steps of doping at least a first portion of the polycrystalline ceramic material with a conversion-enhancing dopant having a +6 valence state in the unfired ceramic material and heating the polycrystalline ceramic material to convert at least a second portion of the polycrystalline ceramic material to a single crystal ceramic material. Preferably, the ceramic material is alumina and the conversion-enhancing dopant is molybdenum or tungsten.

Abstract: An arc discharge lamp comprising an arc tube comprising a starting aid is provided. The starting aid comprises a coating on the surface of the arc tube. The coating is comprised of metal oxide, nitride, carbide, silicide, and mixtures thereof.

Abstract: An electric lamp (100) including a sealed light-transmissive lamp envelope (105) having an interior space, a base fixed to the outer envelope (105), a non-insulated main conductor wire (160) within the outer envelope and connected to the base (110) at one end, a light source (140) capable of generating light within the outer envelope (105), a shroud (145) surrounding the light source (140) and mounted adjacent the non-insulated main conductor wire (160), and a first center support. The light source (140) has first and second ends. The first end is electrically coupled to the non-insulated main conductor wire (160), and the second end is coupled to a stem lead (180). The first center support (150) supports the shroud (145) and the light source (140) and mechanically couples the shroud (145) and the light source (140) to the non-insulated main conductor wire (160).

Abstract: A method of making a component of a ceramic discharge chamber comprising the steps of forming a ceramic composition including an aluminum powder, a binder and a grain growth inhibitor. The alumina powder has a tap density greater than 1.0 gram per cc. The ceramic composition is then die pressed to form a component preform. Next, the component preform is heated to remove at least a substantial portion of the binder.

Abstract: A method of making a component of a ceramic discharge chamber comprising the steps of forming a ceramic composition including an aluminum powder, a binder and a grain growth inhibitor. The alumina powder has a tap density greater than 1.0 gram per cc. The ceramic composition is then die pressed to form a component preform. Next, the component preform is heated to remove at least a substantial portion of the binder.

Abstract: A solid state method of converting a polycrystalline ceramic body to a single crystal body includes the steps of doping the polycrystalline ceramic material with a conversion-enhancing dopant and then heating the polycrystalline body at a selected temperature for a selected time sufficient to convert the polycrystalline body to a single crystal. The selected temperature is less than the melting temperature of the polycrystalline material and greater than about one-half the melting temperature of the material. In the conversion of polycrystalline alumina to single crystal alumina (sapphire), examples of conversion-enhancing dopants include cations having a +3 valence, such as chromium, gallium, and titanium.