Abstract: A matrix addressed display device having a cathode means and grid electrode means comprising an orthogonal array of parallel row conductors and parallel column conductors in which means are providing for selectively applying cut-off and gain correction information to the row conductors and the column conductors. The cut-off and gain correction information may be applied so as to affect all of the display area equally and correct for warm up drift, or it may be applied so as to correct for the effect of a discrete number of hot cathode filaments being used or it may be applied on a pixel by pixel basis.

Abstract: A magnetic matrix display device has a grid electrode in which differing first grid (G1) and second grid (G2) apertures are used. A sensor element and a second grid electrode are combined as a single structure. Other aspects of the invention relate to a deflection anode having reduced capacitance, the use of a polyimide coating for the grid electrodes, the use of a compliant mounting and adjustment for a grid assembly and the provision of an illuminated border on a magnetic matrix display.

Abstract: A magnetic matrix display device has a grid electrode in which differing first grid (G1) and second grid (G2) apertures are used. A sensor element and a second grid electrode are combined as a single structure. Other aspects of the invention relate to a deflection anode having reduced capacitance, the use of a polyimide coating for the grid electrodes, the use of a compliant mounting and adjustment for a grid assembly and the provision of an illuminated border on a magnetic matrix display.

Abstract: An electron source comprises at least one cathode means, and at least one extractor grid which is used to extract electrons from the cathode means. The extractor grid is a substantially planar sheet having at least one aperture and also has at least one spacing member for spacing the extractor grid at a constant, predetermined spacing from the cathode. Each of the spacing members are formed by removing material around a substantial portion of the periphery of the aperture and folding the remaining portion of the periphery of the aperture at substantially a right angle to the planar sheet.

Abstract: A magnetic matrix display device has a grid electrode in which differing first grid (G1) and second grid (G2) apertures are used. A sensor element and a second grid electrode are combined as a single structure. Other aspects of the invention relate to a deflection anode having reduced capacitance, the use of a polyimide coating for the grid electrodes, the use of a compliant mounting and adjustment for a grid assembly and the provision of an illuminated border on a magnetic matrix display.

Abstract: An electron source comprises a permanent magnet having channels within the plate extending between opposite poles of the magnet. The internal surfaces of the channels are conductive. A cathode means is located at a first pole of the magnet, at one end of the channels. Each channel within the magnet has a plurality of perforations located on a surface of the permanent magnet, the surface extending between opposite poles of the magnet. A potential applied between the cathode and the conductive internal surfaces of the channels causes electrons to be received into the channels and each perforation forms electrons received from the cathode means into an electron beam for guidance towards a target.

Abstract: A virtual non-thermionic cathode has the position of a space charge cloud associated with it fixed by the geometry of a fixed insulating layer. The layer can be made to accurate dimensions and hence the cathode to control grid dimension can be accurately controlled and will not change as a result of any mechanical, electrical or physical changes in the construction. The fixed insulating layer is located on a surface of the control grid facing the cathode. A space charge layer is built up on the surface of the insulating layer facing the cathode, and thus emission from the cathode is stabilized.

Abstract: A photo-cathode electron source suitable for use in flat panel displays has an extractor grid means (104) maintained, in use, at a positive potential with respect to the photo-cathode surface. The extractor grid may be used as a carrier for unfired photoemissive material which forms the emission surface of the photo-cathode. The material is deposited on the surface (103) of the photo-cathode means (102) by means of evaporation from the extractor grid (104).

Abstract: An electron source comprises a first permanent magnet having a first channel, extending between first and second poles of the magnet, the internal surfaces of the first channel being conductive. A cathode means is located in the first channel at a first pole of the magnet, a potential being applied between the cathode means and the conductive internal surfaces of the first channel causing electrons to be received into the first channel. A plurality of apertures is located on a wall of the first channel, the wall abutting a second permanent magnet having a plurality of second channels extending between first and second poles of the second magnet. The second pole of the second permanent magnet is adjacent to the aperture located on a wall of the first magnet such that electrons received into the first channel are distributed into the plurality of second channels.

Abstract: A touch screen display is presented which comprises a display screen, a plate of a rigid transparent material, mounting apparatus for mounting the plate on the display screen, touch sensing transducers cooperating with the mounting apparatus for producing a plurality of electrical signals in response to, and representative of, a force applied to the plate; the force results from tactile stimulus of the plate while the mounting apparatus includes a film composed of a transparent, elastic, adhesive compound, having a similar refractive index to that of the display screen; the adhesive compound being applied to one surface of the plate for bonding that surface to the display screen.