International Business Machines Corporation

Christopher Carlo Pietrzak

John S Beeteson

Andrew Ramsay Knox

Anthony Cyril Lowe

Richard Ian Knox

Shaun Carl Kerigan

A magnetic matrix display device has a grid electrode in which differing first grid (G ) and second grid (G ) 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.

Grid electrodes formed on a polyimide substrate for a display device that comprises a permanent magnet

A magnetic matrix display device has a grid electrode in which differing first grid (G,) and second grid (G,) 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.

Grid electrodes for a display device

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.

Self stabilizing non-thermionic source for flat panel CRT displays

A display system for displaying a visual image in response to a video signal (,), comprising; a liquid crystal display panel (,) divided into a plurality of addressable, variable brightness sections (,); address circuit (,) for generating a section address corresponding to a section in response to a timing signal (,); driver circuit (,) for varying the brightness of the section in response to a brightness signal (,) derived from the video signal (,); characterised in that the display system further comprises: a memory (,) for storing a predetermined correction signal (,) corresponding to the section; and control circuit (,) coupled to the driver circuit (,) for varying the brightness signal (,) to reduce brightness non-uniformities in the displayed image in response to the video signal (,) and the correction signal (,) in combination. The control circuit preferably includes a summing circuit for adding the correction signal to the video signal to produce a summed signal for determining the brightness signal. In another preferred embodiment the control circuit includes a voltage control circuit for varying the amplitude of the brightness signal in response to the correction signal.

Display system having section brightness control and method of operating system

An analogue display interface apparatus for providing analog color signals to a digital display unit includes a table look-up mechanism that provides digital representations of color signals to a color palette, wherein some of the values stored in the lookup table are received from the output of a calibration mechanism that displays a plurality of color choices on the digital display unit for selection by a user.

Analog display interface storing color values based upon user controlled

An input device for a visual display comprising a light source and a scanner for angularly scanning a light beam from the light source across a plane. A photodetector detects interruption of the beam by an article positioned in the plane. The scanner comprises a shutter having a linear array of addressable, electrically actuable shutter elements. Each element is operable to transmit or block light from the light source under the control of a corresponding electrical signal. Because the light beam is scanned by a shutter rather than a mechanical scanner, the device is advantageously more reliable than conventional electromechanical optical input devices.

Input device

A display system comprises a digital video source coupled to a digital display device via an digital interface having a timing channel for carrying a pixel clock signal from the video source to the display device and a digital video channel for carrying a digital video bit stream from the video source to the display device. The video source comprises a pixel clock generator for generating the pixel clock signal, palette logic for outputting a pixel word on each pulse of the pixel clock signal, shift clock logic for multiplying the pixel clock signal by the number of bits in the pixel word to produce a shift clock signal, and serialiser logic for serially outputting the pixel word in the serial bit stream at the shift clock signal rate. The display device comprises a display screen for producing a pixel of an image in response to the pixel word; shift clock generator logic for multiplying the pixel clock signal by the number of bits in the pixel word, and deserialiser logic for receiving the input video bit stream at the shift clock signal rate to re-generate the pixel word from the video bit stream.

Display apparatus with digital output palette

A virtual remote cathode has the position of a space charge cloud associated with it fixed by the geometry of a fixed insulating plate. The plate 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 plate is located on a surface of the control grid facing the cathode.

Self stabilizing electron source for flat panel CRT displays

A chemically-machinable glass-magnet composition comprising a photosensitive chemically machinable glass having a magnetic material in admit therewith, wherein the photosensitive chemically machinable glass is formed of SiO.sub.2 --Li.sub.2 O--Al.sub.2 O.sub.3 containing photosensitive materials selected from silver, gold and copper and a cerium dioxide sensitizer; and the magnetic material is a Ni-Cu-Zn ferrite.

Magnet and method for manufacturing a magnet

A display device having a screen is provided in which a back-plate is sealed to the screen to form an evacuated chamber. An area cathode is disposed between the back-plate and the screen. A permanent magnet is disposed between the cathode and the screen. A two dimensional array of rows and columns of channels extends between opposite poles of the magnet for receiving electrons from the cathode. An anode phosphor layer is disposed between the screen and the magnet for receiving electrons from the channels. A grid electrode between the area cathode and the magnet controls flow of electrons from the cathode into the channels, whereas an anode between the magnet and the anode phosphor layer controls flow of electrons from the channels towards the screen. In a preferred embodiment, the cathode means comprises the backplate and a silica glass substrate peripherally sealed to the back-plate to produce a chamber in which a gas is contained. A layer of photo-sensitive material is disposed on the surface of the substrate external to the chamber. A cathode phosphor layer is disposed between the back-plate and the substrate. A pair of electrodes facing each other from opposite sides of the chamber energizes the gas to generate a plasma for exciting the phosphor to generate light energy to produce electron emissions from the photo-cathode.

Display devices

A field emission display comprises a screen (10) divided into a plurality of pixels. Each pixel has a plurality of subpixels (130,140,150) of different phosphor efficacies. A matrix of field emission cathodes (80) is directed towards corresponding pixels of the screen (10). Each cathode has a plurality of arrays (81,82,83) of field emissive tips directed towards corresponding subpixels (130,140,150). The arrays of each cathode (80) comprise different numbers of field emission tips to reduce the effect of the difference in the phosphor efficacies of the corresponding subpixels (130,140,150). This advantageously permits tracking between the primary colour components of a gray scale displayed image to be maintained used the same algorithm to translate into voltages for driving the arrays. Therefore, the Colour Point or White Point of the display can be maintained between extremes of gray scale using the same algorithm. Because the separate algorithms are not required for translating the video signals into gate voltages, the row driver circuitry can be greatly simplified.

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Renfrewshire, United Kingdom

Christopher Carlo Pietrzak