Abstract:
The present invention relates to a method for preparing a rare earth oxysulfide phosphor which comprises baking a mixture containing a rare earth oxide and/or a rare earth compound which becomes a rare earth oxide easily at a high temperature a sulfiding agent and a flux, wherein a rare earth oxysulfide seed is added to the mixture before baking.
Abstract:
There is provided a process for treating the surface of a fluorescent material comprising the steps of adding a suitable amount of water glass (K.sub.2 O.SiO.sub.2) to a dispersion of a fluorescent material, the mixture of the dispersion and water glass being stirred, adding silica particulates to the mixture, and finally adding a suitable amount of metal salt to the mixture containing the silica particulates, whereby the silica particulates adhere to the surface of the fluorescent material.
Abstract:
A cathode ray tube, such as a projection cathode ray tube, having a multilayer interference filter disposed between the cathodoluminescent screen and the interior side of the faceplate, the interference filter comprising alternate layers having high (H) and low (L) refractive indices, the high refractive index material being niobium pentoxide and the low refractive index material being either silicon oxide or magnesium fluoride. These filters are substantially free from the crazing which occurs in known filters when subjected to the normal thermal processing of cathode ray tubes.
Abstract:
A projection television system comprising a cathode-ray tube having a face plate, a display screen coated with a phosphor of the type ZnS:Ag and an interference filter arranged between the display screen and the face plate.The ZnS:Ag has an admixture which slightly increases the y-coordinate of the light emitted by the phosphor.This enables an increased maximum luminance in the white-D-point without the y-coordinate of the light emitted by the cathode-ray tube becoming too low.
Abstract:
There is disclosed a circuit for stablizing the high voltage of the high voltage generating circuit in a CRT according to the change of the horizontal oscillating frequency, comprising a diode, the cathode of said diode being connected to the intermediate terminal of a flyback transformer (FBT), the anode of said diode being connected to first resistor and a variable resistor, a first transistor, the base of the said first transistor being connected to the intermediate terminal of said variable resistor, a second transistor, a third transistor, the collector of said first transistor being connected through a grounded second resistor to the base of said third transistor, the collector of said third transistor being connected to the base of said second transistor, the collector of said second transistor being connected to a direct current source, and a fourth transistor, the emitter of said second transistor being connected through the primary coil of said flyback transformer to the collector of said fourth transistor, the base of said fourth transistor being connected to a horizontal oscillating circuit.
Abstract:
A phosphor for a chathode ray tube obtained by firing a tervalent europium-activated yttrium oxide of the formula Y.sub.2 O.sub.3 :Eu containing at least one member selected from the group consisting of barium fluoride and magnesium fluoride.
Abstract translation:通过焙烧含有选自氟化钡和氟化镁中的至少一种的式Y 2 O 3:Eu的三价铕激活的氧化钇获得的双极射线管的荧光体。
Abstract:
This invention relates to a phosphor prepared by mixing a green emitting phosphor InBO.sub.3 :Tb having an excellent color tone with other green emitting phosphors having a short decay time such as Y.sub.3 Al.sub.5-m Ga.sub.m O.sub.12 :Tb in amounts such that the "decay time to 10% of peak brightness" measured by a raster spot method is below 10 ms. The phosphor screen of a projection cathode-ray tube is formed by use of this phosphor. The projection cathode-ray tube thus produced has an excellent color tone and a short decay time.
Abstract:
A process is disclosed for pigmenting and coating a silver activated zinc sulfide phosphor and for imparting stir-in capabilities to the phosphor. The process comprises deagglomerating the phosphor, forming an aqueous slurry of phosphor particles, pigment particles, a binding agent which can be latex polymers or copolymers, the binding agent having a glass transition temperature of greater than about 20.degree. C. and a silica-based compound to produce a silica based coating on the phosphor particles, and agitating the slurry, separating the solids from the resulting liquor, and drying the solids at a temperature above the Minimum Film Formation Temperature of the latex to produce the phosphor particles wherein the pigment particles are bonded to them and wherein the pigmented phosphor particles are coated with the silica-based coating. The process comprises also pigmenting the phosphor and imparting stir-in capabilities thereto by the process as described above without adding the coating agent to the slurry. The process comprises also coating the phosphor and imparting stir in capabilities thereto by the above process without the pigments and binding agent.
Abstract:
A luminescent screen provided with a luminescent material having the hexagonal crystal structure, which material is an aluminate, a gallate or an aluminate gallate. The crystal structure of the luminescent material corresponds to that of at least one of the compounds .beta.-aluminium, .beta."-alumina and the hexagonal ferrites. The luminescent material is activated by at least one of the elements manganese, europium, lead, thallium, cerium, indium, terbium, dysprosium and bismuth and is a ternary compound whose composition can be represented in the ternary phase diagram ABC in which A represents at least one of the oxides 1/4Na.sub.2 O, 1/2K.sub.2 O, 1/2Rb.sub.2 O, 1/2Cs.sub.2 O, CaO, SrO, BaO, 1/2La.sub.2 O.sub.3, 1/2Ce.sub.2 O.sub.3, 1/2Tb.sub.2 O.sub.3, 1/2Dy.sub.2 O.sub.3, 1/2Bi.sub.2 O.sub.3, EuO, PbO, 1/2Tl.sub.2 O and 1/2In.sub.2 O, in which B represents at least one of the oxides Al.sub.2 O.sub.3 and Ga.sub.2 O.sub.3 in which up to 25 mol. % of the oxides denoted by B may be replaced by Sc.sub.2 O.sub. 3 and in which C represents at least one of the oxides MgO, ZnO, BeO, 1/2LiAlO.sub.2 and 1/2LiGaO.sub.2. The content of A is more than zero and less than that of B and the content of C is more than zero and less than 0.6
Abstract:
The luminescent screen of a cathode ray tube includes an array of monocrystalline or amorphous phosphor rod-like elements which are covered with a reflective coating except for one end of each element which serves as an output face. The phenomenon of the light trapping is advantageously exploited to achieve enhanced brightness. The screen is illuminated with an electron beam which has an essentially oblong cross section and which is oriented along the elongated dimension of the elements. In one embodiment the elements comprise epitaxial Lu.sub.3 Al.sub.3 Ga.sub.2 O.sub.12 :Ce on the top of a YAG substrate, and a light absorbing layer of Lu.sub.3 Al.sub.3.5 Fe.sub.1.5 O.sub.12 is formed on the bottom of the substrate. A printer utilizing such a CRT is described. Also described is a configuration in which each of the rod-like elements functions as a laser.