U.S. Philips Corporation

Pieter Hokkeling

Johannes M Van Esdonk

Jan Hasker

Josef J Van Lith

Roger J Van Den Plas

Gustaaf A Wesselink

Jacobus E Crombeen

Willem H Diemer

Hubertus F Wagemans

Cornelius D Roelandse

Petrus A Van Dorst

For maintaining a monolayer of scandium which is necessary for a satisfactory emission on the surface of a scandate cathode, at least the top layer of the cathode is provided with scandium coated with a scandium oxide film. Even after repeated ion bombardment the emission is found to recover up to approximately 90% of the initial value at a current density of ca. 100 A/cm.sup.2.

Method of manufacturing scandate cathode with scandium oxide film

The invention relates to an X-ray tube having a rotary anode which is rotatably supported in a vacuum-tight housing by at least one metal-lubricated sliding bearing of which at least the cooperating bearing surfaces consist of a W-alloy and in which the lubricant is Ga or a Ga-alloy. In order to extend the life of the X-ray tube, in particular at operating temperatures of the bearing above 400.degree. C., a mechanically readily machinable W-alloy is used which comprises from 2 to 27% by weight of Re.

X-ray tube having a rotary anode with rhenium-containing bearing

A method of manufacturing a scandate dispenser cathode having a matrix at least the top layer of which at the surface consists substantially of tungsten (W) and scandium oxide (Sc.sub.2 O.sub.3) and with emitter material in or below said matrix. If said method comprises the following steps:

Method of manufacturing a scandate dispenser cathode and dispenser

In an X-ray tube, particularly for the detection of elements having a low atomic number by X-ray spectral analysis, an anode support (4) is on the target side provided with a layer (7) of scandium. The scandium layer is provided on the support by adhesion via an intermediate layer (8), preferably of chromium. In a reflection tube, the anode support for the intermediate layer and the scandium layer is preferably made of silver or copper. In a transmission tube, the scandium is provided on a beryllium disc which acts as intermediate layer and as an exit window (6).

X-ray tube for generating soft X-rays

In electric lamps a type of glass is used for the envelope which, in many cases, has a coefficient of expansion which differs considerably from that of the current supply conductors. Therefore, special measures have to be taken to seal the lamp envelope in a vacuum-tight manner around the current supply conductors. The invention provides a simple, vacuum-tight seal of a lamp envelope (1), which seal consists of a metal plug (8, 9, 11) which is sealed both to the glass of the lamp envelope (1) and to the current supply wires (4, 5, 10). The metal plug (8, 9, 11) of 100 parts by weight of a first metal (tin and/or lead) 0.05-1 parts by weight of a second metal (titanium, zirconium, hafnium, niobium, tantalum, and vanadium) has a strong adhering power and a large ductility.

Electric lamp

The invention relates to an electric lamp having a pinch seal in which a molybdenum foil is incorporated as a current leadthrough conductor. An external current conductor is connected to the foil. As a result of differences in coefficients of expansion, a capillary space is present around the external current conductor, through which space oxidizing gas can reach the molybdenum foil. Oxidation of the foil involves an increase of its volume and results in crack of the pinch seal. In lamps according to the invention a metal plug is provided around the external current conductor, said plug being sealed to said current conductor and to the glass of the pinch seal and sealing the capillary space in a vacuum-tight manner.

Electric lamp with tin or lead alloy plug for lead-in

A low-pressure mercury vapor discharge lamp having a discharge space provided with two thermally emitting electrodes as well as an amalgam of bismuth, indium and mercury, characterized in that the ratio of atoms of bismuth to atoms of indium is between 0.4:0.6 and 0.7:0.3 and the ratio of atoms of mercury to the sum of the atoms of bismuth and indium is between 0.01:0.99 and 0.15:0.85.

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Eindhoven, Netherlands

Pieter Hokkeling