A luminaire is disclosed comprising a fluorescent plastics outer sleeve having a configuration such that a high proportion of the fluorescent light generated within the sleeve is emitted as visible light. The sleeve includes a fluorescent dye, which dye is excited by a blue phosphor discharge.

Radioactive sources are made from a foil (10) containing radioactive material, by cutting out hexagonal foil elements (12) from the foil, leaving no uncut portions of foil between adjacent hexagonal foil elements. This significantly induces wastage of radioactive foil.

A closed loop exit hole is formed in a magnetically permeable end wall (2) of an enclosure (1) of a closed electron drift ion source. Parts of this end wall separated by the exit hole serve as pole pieces (7 and 8) of the magnetic system and define the first pole gap. The magnetic system includes pole pieces (9 and 10), which define the second pole gap made in the form of a closed loop exit hole and arranged along the direction of ion emission. Magnetomotive force sources (5 and 6) are located i...

A radiation source comprising a lamina of amorphous or predominantly amorus polymer material having appreciable electrical charge mobility and a low ionization potential; a strong electron donor; a strong electron acceptor; and preferably at least one fluorescent additive; electrical connections being provided by which an electric current may be passed through the thickness of said lamina to excite radiation therefrom.

The invention relates to methods of controlling the effect of ions of an ionisable source gas that can react with interior surfaces of an arc chamber, by introducing ions of a displacement gas into the arc chamber, where the displacement gas ions are more chemically reactive with the material of the interior surfaces than the ions of the source gas. The source gas ions may typically be oxygen ions and the displacement gas ions are then typically fluorine ions where the interior surfaces comprise...

An electron source having a rapid response time comprises at least one n-p-n structure (and possibly an array of said n-p-n structure) formed in a silicon or other semiconductor body (10) by a p-type first region (1) between n-type second and third regions (2 and 3). Electrons (24) are generated in the n-p-n structure (2,1,3) for emission into free space (20) from a surface area (4) of the body (10) after flowing from the second region (2) through the first and third regions (1 and 3). The n-p-n...

An electron source having good electron emission efficiency comprises a silicon or other semiconductor body (10) having an n-type first region (3) which is separated from an n-type or p-type second region (2) by a barrier. The barrier may be a p-n junction between p-type region (2) and the n-type region (3), or it may be a p-type region (1) forming p-n junctions with the n-type regions (2 and 3). By means of electrode connections (13 and 12) to the first and second regions (3 and 2) a potential ...

New arsenate compounds, compositions and solid diffusion sources for the arsenic doping of semiconductors are disclosed which comprise substances composed of a sintered arsenate that decomposes upon heating at temperatures between 500.degree.-1400.degree. C. to release As.sub.2 O.sub.5, As.sub.2 O.sub.3 and/or elemental arsenic vapors for transport to semiconductor elements as a controlled dopant.

An isotope capsule carried at the end of a radio-active source holder is handled by retracting the source holder from one position into a curved passage of a guide member through an inlet at one end of the passage, turning the guide member through an angle of less than 360.degree. about the central axis of the other end of the passage, and then ejected through the inlet into a different position. Manipulating apparatus for withdrawing and inserting the radio-active source holder from and to a ho...

A reflector for linear light sources and particularly for fluorescent tubes. The reflector has a substantially V-shaped cross-sectional configuration. For use in an array of lamps comprising a plurality of light sources arranged in parallel, a plurality of reflectors of the type disclosed may be assembled to form a reflector arrangement corresponding in size to the array of lamps, with the assembly in its entirety being sawtooth-shaped in cross-section.