Osram Sylvania Inc.

Jeffrey T Neil

Victor E Perez

Gregory Zaslavsky

Joseph V Lima

Matthew Stough

Walter Peter Lapatovich

Arlene Hecker

Lori R Brock

Joseph E Lester

Karlene J Zuk

Christopher A Tarry

Timothy J Horton

Lewis H Palmer, Iii

Matthew A Stough

A ceramic discharge lamp and a method of making the lamp includes a ceramic discharge chamber with two concave parts that are attached to each other at a seam, and a ceramic reflector directly attached to an exterior surface of the discharge chamber at the seam, or directly attached to a ceramic capillary that is attached to one of the two concave parts. The lamp finds particular application where focused light is required, such as injection of light into a fiber optic device. The lamp can be very small and has an advantage that the discharge chamber is isolated from the reflective surfaces so that the optically active parts of the reflector are not covered with salt from the preferred metal halide lamp fill.

Ceramic discharge lamp with integral burner and reflector

A single-ended ceramic discharge lamp is described which has an integral optical surface such as a parabolic or elliptical reflector. The single-ended configuration eliminates the need for the mounting structures found in double-ended lamps that can interfere with the light emitted from the lamp, particularly in focused beam applications.

Single-ended ceramic discharge lamp

An incandescent lamp that emits infrared light and a method of making the lamp includes a filament assembly inside a polycrystalline aluminum oxide (PCA) envelope, where the filament assembly preferably has a coiled tungsten filament, solid metal ends of tungsten or molybdenum attached to the coiled tungsten filament, and leads at distal ends of the solid metal ends. End caps are attached to ends of the envelope and have openings through which a respective one of the leads extends, where the leads are each made of an electrically conductive material having a coefficient of thermal expansion compatible with the end caps, such as niobium. The leads are attached to the end caps with glass-ceramic sealing frits. The end caps and sealing frits seal a suitable gas inside the envelope.

Incandescent lamp that emits infrared light and a method of making the lamp

A method of molding a ceramic vessel includes compressing a water-soluble powder, suspending the compressed powder shape in a mold, injecting a ceramic molding mixture into the mold, and dissolving the compressed powder by flushing the vessel with water. A core for making an arc discharge vessel that has a discharge chamber and two capillaries includes a molded core of the water-soluble powder having a shape of the discharge chamber, and preferably two capillary-forming pins extending from the molded core. An apparatus for removing the molded core that includes a water reservoir that preferably flushes water through the vessel and dissolves molded core.

Core for molding a ceramic discharge vessel

An assembly for forming a hollow, ceramic arc discharge vessel for high-intensity discharge (HID) lamps is described wherein a means for self-alignment of two molded sections is provided. In particular, the sealing surface of one section of the arc discharge vessel is provided with a convex surface and the sealing surface of the other section is provided with a concave surface. The radius of the convex sealing surface is smaller than the radius of the concave sealing surface so that the sections may self-align during joining, preferably without gas entrapment in the seal.

Assembly for forming a ceramic arc discharge vessel and method of manufacture

A method for reducing the loss of magnesium during the sintering of aluminum oxide articles, such as ceramic discharge vessels for lighting applications. Magnesium oxide is added to aluminum oxide articles to control grain growth during sintering, but the sintering causes magnesium loss from the article. In order to address this problem, one or more aluminum oxide articles that are enriched in magnesium oxide are added to the sintering furnace to stem the loss of magnesium oxide in the remaining articles. The enriched aluminum oxide article is made by soaking a porous aluminum oxide article in an aqueous solution of magnesium nitrate and heating the porous article to convert the magnesium nitrate to magnesium oxide. The enriched articles may then be added in one or several locations to the sintering furnace, where the magnesium from the enriched articles is released to suppress the magnesium loss.

Method of reducing magnesium loss during sintering of aluminum oxide articles

A ceramic discharge vessel for a high-intensity discharge lamp includes a hollow body and two capillaries attached to the body. The capillaries have respective electrodes therein, where portions of the electrodes inside the body are spaced from each other and have longitudinal axes that are not coplanar. That is, in contrast to the prior art where the longitudinal axes are coplanar, the capillaries herein are moved (in effect, rotated) to positions in which a first plane defined by a longitudinal axis of one capillary and a first point where a second capillary is attached to the body is intersected by a longitudinal axis of the second capillary only at the first point.

Single-ended discharge vessel with diverging electrodes

A ceramic discharge vessel in a green state prior to assembly includes a first discharge vessel part in a green state, a second discharge vessel part in a green state, wherein the first and second discharge vessel parts form a discharge vessel when joined together, and a first capillary attached to the first discharge vessel part and a second capillary attached to one of the first and second discharge vessel parts. To facilitate joining the first and second discharge vessel parts, a first removable handle is temporarily attached to the first discharge vessel part for maneuvering the first discharge vessel part, and a second removable handle is temporarily attached to the second discharge vessel part for maneuvering the second discharge vessel part.

Green-state ceramic discharge vessel parts

A ceramic arc tube assembly and a method for making a ceramic arc tube are described which simplify the manufacture of ceramic arc tubes by reducing the number of handling and heat treatments required to assemble arc tubes prior to the final sintering operation. In particular, the invention uses transient assembly buttons during intermediate assembly steps which are removed prior to the final sintering operation.

Method of making a ceramic arc tube

Ceramic arc tube assembly

A method of making a ceramic arc tube for a metal halide lamp comprises the steps of forming as an integral unit a hollow body having one open end and a substantially closed end. The substantially closed end includes an outwardly extending capillary tube having an electrode receiving aperture therein that communicates with the hollow body. An end cap is then formed for closing the open end. The end cap comprises an annular portion and an extending capillary tube, The end cap is fitted into the open end of the hollow body to form a pre-assembly. The pre-assembly is then fired to seal the end cap to the hollow body to form an assembly and the assembly is subsequently fired to sinter the same.

Method of making a ceramic arc tube for metal halide lamps

A method of forming hollow bodies of ceramic material suitable for use as the discharge vessels of high intensity discharge lamps includes forming a fugitive core of substantially pure graphite having a configuration matching the interior configuration of the hollow body. A flowable powder, including binders, of the ceramic material is formed and added to fill the annular space between a flexible elastomeric mold defining the outer contour and the fugitive core defining the inner contour. The ceramic powder is isostatically compressed in the mold about the core to form a sub-assembly. The sub-assembly is removed from the mold, heated at a rate and time and in a suitable atmosphere to volatilize the fugitive core, and subsequently the sub-assembly is sintered to form the hollow body.

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North Reading, MA, United States of America

Jeffrey T Neil