摘要:
A metal/ferrite laminate magnet has perforations forming apertures in the magnet. The magnet is formed of outside metal plates surrounding a sandwich of two layers of ferrite material. The outside metal plates allow the perforations to be made in the magnet before sintering of the magnet and maintain the alignment of the holes during sintering. The metal plates also provide the magnet with mechanical robustness and rigidity and prevent cracking occurring between adjacent apertures.
摘要:
A metal/ferrite laminate magnet has perforations forming apertures in the magnet. The magnet is formed of outside metal plates surrounding a sandwich of two layers of ferrite material. The outside metal plates allow the perforations to be made in the magnet before sintering of the magnet and maintain the alignment of the holes during sintering. The metal plates also provide the magnet with mechanical robustness and rigidity and prevent cracking occurring between adjacent apertures.
摘要:
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.
摘要:
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).
摘要:
A display device includes a cathode for emitting electrons and a permanent magnet. A two dimensional array of channels extends between opposite poles of the magnet. The magnet generates, in each channel, a magnetic field for forming electrons from the cathode into an electron beam. A screen receives an electron beam from each channel. The screen has a phosphor coating facing the side of the magnet remote from the cathode. The phosphor coating comprises a plurality of pixels each corresponding to a different channel. A grid electrode is disposed between the cathode and the magnet for controlling flow of electrons from the cathode into each channel. A deflection sequentially addresses the electron beam from each channel to each pixel of the corresponding group. Rotational alignment APPARATUS aligns electron beams from the channels with corresponding pixels of the phosphor coating. The rotational alignment comprises a resistive deflector and apparatus for generating a differential voltage across one or more elements of the deflector. The magnitude and direction of the differential voltage across one or more elements of the deflector is used to provide rotational alignment.
摘要:
A display device includes field emission cathode apparatus for emitting electrons. A plurality of electron beams are formed from the field emission cathode apparatus. A screen, which has a phosphor coating facing the cathode receives the plurality of electron beams. The phosphor coating includes a plurality of pixels each corresponding to a different one of said plurality of electron beams. A grid electrode is disposed between the cathode and the screen for controlling the flow of electrons from the cathode. The field emission cathode includes extractor grid means, having a plurality of separately addressable portions associated with each of said plurality of pixels. A gamma transfer function between input data value and beam current is provided in order to emulate a conventional CRT. This can be achieved by use of a lookup table.
摘要:
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.
摘要:
An improved orientation system includes a lens pre-distorting an image generated by imaging apparatus such that a non-linearity, the degree of which is dependent on the off-axis distance of an imaged object, is generated so as to increase the strength of a signal indicating said non-linearity.
摘要:
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.
摘要:
A vacuum electron device comprises an evacuated envelope containing a cathode for supplying electrons to form an electron beam, an anode spaced from the cathode for receiving the electron beam, and a sensor electrode located between the cathode and the anode.