Abstract: To provide a lamp device that is a point light source, that withstands high pressure, and that produces high-intensity light, a high-frequency excitation point light source lamp device has been devised having a discharge vessel made of a transparent, non-conductive material and having an expanded part forming a discharge space and with tubules joined to the expanded part; at least one discharge concentrator, that concentrates the electrical field within the discharge space of the expanded part, which is supported in a tubule with an end within the discharge space; and a high-frequency supply external to the lamp for providing excitation energy that excites a discharge of the concentrator.

Abstract: A cermet which contains an aluminum oxide component, a silicon dioxide component, a component for modifying the coefficient of linear expansion which is formed of a metal oxide other than aluminum oxide and silicon dioxide, and a metal component with a smaller coefficient of linear expansion than aluminum oxide. A ceramic discharge lamp which has a discharge vessel with an arc tube part and hermetically sealed tube parts, in which furthermore in the arc tube part there are a pair of discharge electrodes opposite one another, and in which a hermetically sealed arrangement is obtained by fritting-welding of hermetically sealing components with the hermetically sealed tube parts, in the hermetically sealed components the base parts of the upholding parts of the electrodes being inserted, on the tips of which the discharge electrodes are located, and in which the hermetically sealing components are formed of the above described cermet.

Abstract: The object of the invention to devise an electrical insertion body for a tube lamp in which sealing bodies of an electrically conductive inorganic material component and a dielectric inorganic material component and upholding parts of the electrodes are attached securely to one another by sintering, and in which neither leaks nor falling out of the upholding parts of the electrodes occur.

Abstract: A discharge lamp manufacturing method that provides control of the introduction of a predetermined amount of halogen, unaccompanied by carbon or hydrogen, into a discharge vessel of the lamp so that a discharge lamp having an adequate operating pressure and that can maintain enhanced lighting conditions over a long period can be achieved. In particular, a halogen-introduction carrier is used in the manufacture of the discharge lamp for introducing a predetermined amount of metal halide. The discharge lamp manufacturing method includes a device for introducing halogen into the discharge vessel and includes heating a halogen-introduction carrier composed of a porous body containing metal halides.

Abstract: An electricity introducing member for a tube lamp includes a closing member and an electrode upholding part formed integrally together; the closing member includes a plurality of layers each comprising a conductive component and silica, the volumetric proportion of the silica being n1, n2, n3, . . . , nx such that n1>n2>n3> . . . >nx, are successively laminated in the form of a cylinder, so that the closing member serves as a functional gradient material; where the diameter of the closing member is D in mm and the total thickness of the laminate of the layers each containing more than 80 volume % of silica is L in mm; L/D is not less than 2: the electrode upholding part is shrink-fitted from the surface on the side of the layer n1 up to the layer containing at most 80 volume % of silica in the closing member. Preferably, where the diameter of the electrode upholding part is d in mm, the ratio of d/D is from 0.12 to 0.6.

Abstract: A ceramic lamp in which the hermetically sealing bodies of electrically conductive cermet are sealed to hermetically sealed tube portions of the lamp vessel with a sealing material is arranged and provided with material components designed to give the hermetically sealing portions a high reliability.

Abstract: Sealing body for a discharge lamp which consists of a functional gradient material in which one side is rich in dielectric component and the other side is rich in electrically conductive component, and which is sealed by a side tube which is connected to the arc tube of the discharge lamp and by its areas which are rich in a dielectric component, characterized in that in this sealing body an upholding part of an electrode with a tip provided with an electrode is shrink-fitted, and that furthermore on the outer peripheral surfaces of the areas of the sealing body which are rich in dielectric component, surfaces are formed which run obliquely with respect to the center axis of the above described discharge lamp so that the maximum width of the end face of the sealing body on the side of the emission space becomes smaller than the maximum width in one direction perpendicular to the axis of the sealing body and becomes greater than the diameter of the upholding part of the electrode.

Abstract: In sealing body (6) of a tube lamp which seals side tube (3) which is connected to arc tube (2) and which securely holds upholding parts (7) of the electrodes by a shrink seal and which consists of a functional gradient material, in which an electrically conductive component and a dielectric component in the axial direction of the tube have a continuous or gradual concentration gradient, and in which one side is dielectric and the other side is electrically conductive, the object of the invention is achieved by upholding parts (7) of the electrodes being located in an opening of this functional gradient material without a gap in a shrink seal, and by the surface of the area of upholding parts (7) of the electrodes which are located in the opening of the functional gradient material being coated at least partially with thin layer (9) of a metal with a high melting point.

Abstract: A low pressure discharge lamp in which, even during uninterrupted operation, a low lamp voltage characteristic is maintained over a long time interval and in which high radiant efficiency can be obtained over a long time is achieved via a low pressure discharge lamp which has a tubular glass bulb in which a pair of electrodes are located opposite one another, by an electron emission material which contains lithium being included on or in the electrode substrate. Advantageously, the electron emission material contains at least one of the following materials: metallic lithium, an alloy of lithium and another metal, an oxide of lithium, a mixture of an oxide of lithium with another metal oxide, and an oxide which contains lithium and another metal element and which is a compound identified by the formula Li--M--O.sub.x where M designates at least one element selected from among the alkali earth metals, rare earth metals and transition metal, and x is the number of oxygen atoms required for valency equalization.