Abstract: A method of driving a plasma display panel uses a frame time-division multiplexing method wherein a frame is divided into a plurality of subfields and each subfield is allocated to a different sustain period. In this method, a frame is divided into two groups, and the number of subfields wherein a preliminary discharge is performed on each group is made to be the same or smaller than that of subfields wherein a preliminary discharge is not performed. Under this condition, thereby preventing the deterioration of the selective write rate due to an unequal discharge condition among cells and improving contrast by lowering background brightness of the picture.

Abstract: An electron tube cathode is disclosed, comprising a base, electron emissive material layers formed on the base and containing alkaline earth metal oxides including barium, and reducing metal layers interposed between the emissive material layers. The metal layers comprise at least one metal selected from W, Mo, Ta and Ti. The metal layers further comprise any one of rhenium, yttrium or a mixture thereof in the amount of 3 to 5 wt % thereof. The amount of the entire metal layer is 8 to 15 wt % of the entire emissive layer comprising the emissive material layers and the metal layers. The entire metal layer has a thickness of 3 to 5 &mgr;m. Each of the metal layers comprise at least one or more layers formed by means of a spraying method. The present invention provides advantages of enhancing emission characteristics and life characteristics of the cathode by increasing the amount of free Ba.

Abstract: An improved clutch device for transmitting the motive power from an associated follower pulley to a selected reel support via an associated idler gear in a videotape recorder. It comprises a top clutch fixed to the top of the axle of the follower pulley, and a coupling gear urged by an associated coiled spring apart from the top clutch and fitted around the top clutch. The top. clutch has a plurality of nail pieces integrally connected to and descending from its circumference. Each nail piece has two ramp-shaped indents formed on its opposite sides. The coupling gear has rib pieces integrally connected to and descending from its circumference. Each rib piece has a counter ramp-shaped indent inside, thereby allowing one or the other ramp-shaped indent of each nail piece to engage with the counter ramp-shaped indent of each rib piece while the top clutch is made to descend in the annular space of the coupling gear, thus preventing further descent of said top clutch.

Abstract: A reel support for rotating reels in a magnetic tape cassette inserted in a magnetic tape recording-and-playing apparatus, is a resin mold and comprises a support stage having a reel post and blades integrally connected to and standing upright from the support stage. The upright blades extend in the longitudinal slots made in the circumference of the upright reel post. Each upright blade has a nail formed on its tip end, partially appearing from the circumference of the upright reel post to the extent of being caught by a selected projection in the indented-aperture of either reel. Each longitudinal slot has a stepwise indent formed on one side facing the tail side of the nail of the blade, thus permitting the corner of the nail to be engaged with the stepwise indent of the one side of the longitudinal slot when the blade is yieldingly bent as a counter action to the pushing of the confronting projection.

Abstract: Disclosed a color purity and convergence magnet (PCM) for a color cathode ray tube capable of fine-adjusting irrespective of the position of the axial direction of the tube, reducing the influence of an adjusting magnetic field on an electron gun, and increasing the workability for the color cathode ray tube.

Abstract: Disclosed is an improved friction type of power transmission mechanism for driving a reel support in a VTR wherein the power is transmitted from the motor to the reel support via the follower pulley, which is sandwiched and clamped between a base disk and an annular plate. The follower pulley has a first friction ring sandwiched between the base disk and the lower flange surface of the follower pulley and a second friction ring sandwiched between the annular plate and the upper flange surface of the follower pulley. With this arrangement an increased torque can be produced without causing excessive abrasion. The diameter of the circular opening of one of the first and second friction rings is equal to or larger than the outer diameter of the other friction ring. This has the effect of saving the material of friction ring.

Abstract: A method of displaying a halftone image on a PDP display unit by using a frame division technique, the method comprising selecting display lines whose number is identical to the total number of said divided subfields, addressing for designating pixels of selected display lines to be displayed and displaying each subfield allocated for the said selected display lines; shifting by a predetermined number of display lines from said selected display lines for at least a sustain pulse period unit, selecting display lines, addressing for designating pixels to be displayed and displaying each subfield allocated for the said selected display lines; and repeating said shifting, said selecting, said addressing and said displaying steps until each of the subfields is completely displayed for all display lines; wherein display lines for which all subfields of one frame have been completely displayed for an idle period.

Abstract: A glass plate having high-electroconductive film which can be formed using electroconductive organic polyrmer in a simple method and at a low cost, and having an improved anti-static characteristic with a strong film hardness and a strong adhesive strength. The glass plate has an anti-static film (10, 20) formed on the exterior surface, the film comprising a first coating layer (11, 21) formed containing an electroconductive organic polymeric component and a second coating layer (12, 22) of silica coating formed by being overcoated onto the first coating layer (11, 21). The electroconductive organic polymeric solution contains 0.005-0.5 wt. % of polyethylenedioxythiophene which polystyrenesulphonate is doped to and silicon alkoxide of below 10 wt. %, and also may contain 40-90 wt. % of at least one a selected from a group consisting of a methanol, an ethanol, an isopropanol, a butanol, and combinations thereof, 5-70 wt. % of pure water, and 1-20 wt.

Abstract: The present invention generates a cell driving apparatus of a field emission display capable of increasing a grey level and minimizing an area problem by designing a current mode DAC which contains low voltage devices.

Abstract: Disclosed is a wire-type corona charger having a wire electrode disposed between ground electrode plates. The wire electrode is supported by the ends of the plurality of wire electrode supporters which are so arranged that their ends have a curvature equal to arcuately-shaped upper edge of the ground electrode plates. The curvature coincides with one of the curvatures of the horizontal axis and the vertical axis of the interior surface of the panel faceplate, while the charger is pivoted along the other curvature of the faceplate. The charger can uniformly charge the photoconductive layer and improves the charging efficiency.

Abstract: An electron gun has a plurality of grid electrodes for focusing electron beams radiated from cathodes, at least one of said grid electrodes having a cylindrical body containing a plate member. The plate member has a central electron-beam-passing-aperture and two side apertures. At least one of the two side apertures is contoured by a first circular arc and a second circular arc, two first vertical lines respectively extending outward from either ends of the first circular arc, two second vertical lines respectively extending outward from either ends of the second circular arc, and two connecting lines respectively connecting each of outer ends of the first vertical lines to each of outer ends of the second vertical lines. The electron gun improves the degree of freedom in controlling shapes of beam spots focused on a phosphor screen, thereby heightening the resolution of the cathode ray tube.

Abstract: Disclosed is an impregnated cathode structure for a cathode ray tube and its manufacturing method, in which electron emitting material impregnated in a pellet is free from an effect of the welding heat generated when the pellet is secured to a heater sleeve. The impregnated cathode structure has a pellet assembly including a pellet and a pellet fixing sheet. The pellet is attached to a first surface of the pellet fixing sheet, which has a plurality of protuberances. The pellet is manufactured by pressing and sintering, and impregnating electron emitting material into the porous of the pellet. The pellet sleeve is inserted in and welded to a heater sleeve. A heater sleeve is welded to a second surface of the pellet fixing sheet, which is opposite to the first surface.

Abstract: AC Plasma Display Panel with a reverse surface discharge with each display element comprises at least, one display discharge gap formed by the address and common electrodes, and the control and address display electrodes wherein the number of the display is n≧3, and geometric parameters of all above gaps and gas filling is determined from conditions of the reverse surface discharge.

Abstract: A method for coating phosphor particles with polymers improves chargeability for use of these particles in CRT screens. The method includes injecting the phosphor particles into a reactor with the use of hexane as the solvent and styrene as a monomer. The particles are agitated and kept hot in the reactor. AIBN is injected into the reactor as a first, second and third catalyst, at one hour intervals. After injecting the third catalyst, a co-catalyst dissolved in hexane is also injected into the reactor. The co-catalyst is cobalt naphthalate. The method then includes cooling, drying, shattering and filtering the particles.

Abstract: Disclosed are a solution for making a photoconductive layer in dry-electrophotographically manufacturing a screen of a cathode ray tube and a method using solution. By the solution, the photoconductive layer can be stored for long time and reveals a superior photoconductivity. The solution has tetraphenyl ethylene derivatives as an electron donor material responsive to the ultraviolet rays, which has structural formula (I), in which R is H, CH3, C2H5, C3H7, OCH3, OC2H5, OC3H7, or COCH3, on a condition of excepting a case where R1═R2═R3═R4═H.

Abstract: A method of electrophotographically manufacturing a viewing screen including a filter layer of pigment particles for a cathode-ray tube (CRT), which comprises the steps of first-coating of volatilizable conductive layer, second-coating the conductive layer with a volatilizable photoconductive layer, first-establishing a uniform electrostatic charge over the whole surface of the photoconductive layer, first-exposing selected areas of the photoconductive layer to a light source, first-developing the discharged, exposed areas with one kind of charged pigment particles, and fixing the developed pigment particles to the photoconductive layer to form a filter layer beneath one of first to third color-emitting phosphor particles. Then, the one of first to third color-emitting phosphor particles is formed on the filter layer by a electrophotographically manufacturing method.

Abstract: The present invention relates to a method for manufacturing a spacer used in a flat panel display. At the first printing process, a printing mask produces a primary spacer on a substrate. After removing the printing mask, a supporting plate having a hole to excess the primary spacer is placed on the substrate and then the printing mask is rearranged on the supporting plate. A subsequent printing process is applied repeatedly to the printing mask with the supporting plate to extend the height of the primary spacer to the amount of the thickness of the supporting plate, thereby producing an elongated finished spacer.

Abstract: The present invention is to provide an apparatus for driving a flat panel display which allows the amount of electrons emitted from a cell to be easily controlled and which performs a stable display gradation processing. To this end, the present invention comprises a shift register for sequentially shifting a video signal input from the exterior in synchronism with a clock signal; a latch for temporarily storing and outputting said video signal which has been sequentially inputted from said shift register; an AND gate for adjusting the time of outputting said video signal output from said latch; and an output driving circuit for inputting said video signal from said AND gate and performing a display gradation control. The present invention allows the amount of electrons emitted from a cell to be easily adjusted so that a 16 step of gradation processing of a display is made possible.

Abstract: An alternating current plasma display panel with a surface discharge. The panel comprises in each pixel three parallel electrodes, one of the three parallel electrodes being an address electrode, and drive electrodes being perpendicular to them, the three parallel electrodes, the three parallel electrodes, and the drive electrode being separated by dielectric barrier ribs, geometric parameters of electrodes, discharge gaps and gas filling being determined from conditions needed for execution of a surface discharge by sustaining voltage pulses in a pixel between two extreme parallel electrodes with the address electrode arranged between them. When the discharge gap length is increased in the luminescence area, power does not increase but brightness is improved. The ratio of brightness of new/standard and the ratio of power new/standard becomes 1.1-2.3 times better.

Abstract: A cell driving device of a field emission display according to a passive matrix addressing method having a field emission pixel cell with a cathode (10) and a gate electrode (12) for emitting electrons from the cathode. The cell driving device includes at least two current sources (18, 20) disposed to provide a current signal to the cathode; and a controlling part (22) for selectively driving at least two current sources (18, 20) according to the size of a video signal.