Abstract: A color cathode-ray tube including a main lens section comprising an anode to which an anode voltage is applied, and a focus electrode. The focus electrode has first type of focus electrode group to which a first focus voltage is applied, and a second type of focus electrode group to which a second focus voltage is applied which is obtained by superposing on a predetermined voltage a voltage that changes depending upon the deflecting amount of the electron beams. Between the first type of focus electrode group and the second type of focus electrode group are formed in a dynamic lens and an electrostatic quadrupole lens. Three electron beam passage holes are formed in the electrodes that form the dynamic lens and the centers for the outer electron beam passage holes in the first type of focus electrode group are deviated relative to the centers of the outer electron beam passage holes in the second type of focus electrode group in the horizontal direction.

Abstract: In a color picture tube, a main lens of an electron gun is formed by a focus electrode to which a focus voltage, is applied an intermediate electrode to which an intermediate voltage between the focus voltage is applied and an anode voltage, and an anode electrode to which the anode voltage is applied. The focus electrode and the anode electrode are cylindrical, and plate electrodes are secured to the inner walls of the respective focus and anode electrodes, and the intermediate electrode has a construction in which a middle plate electrode is sandwiched between two cylindrical electrodes. Accordingly, it is possible to provide an electron gun which is easy to manufacture and has a superior focus performance and is reduced in performance variability.

Abstract: A color cathode-ray tube has a fluorescent body film having picture elements of three colors. A shadow mask provided for the color cathode-ray tube is a color selection electrode and is installed close to the fluorescent face. An electron gun includes a cathode, a first electrode and a second electrode for discharging three electron beams in parallel and in a common plane. Further, the electron gun includes the main lens, which contains several electrodes that focus the three electron beams on the fluorescent face. The average diameter D of the vertical and the horizontal dimensions of the electron beam pass hole in the first electrode, the first electrode thickness T, and the space B between the electron beam pass hole in the first electrode and the electron beam pass hole in the second electrode are defined in an area that is surrounded by four straight lines that are expressed by the following relations, where A=D3/T: 100A=154B+17, 1000A=1420B+17, A=0.6, B=0.08.

Abstract: A focus electrode 4 is constituted by first type of focus electrode groups 43, 45 to which a first focus voltage is applied, and second type of focus electrode groups 44, 46 to which a second focus voltage is applied. Between the first type of focus electrode groups and the second type of focus electrode groups are formed a lens for correcting the field curvature and an electrostatic quadruple lens. The center axes of the outer electron beam passage holes in the first type of focus electrode forming the lens for correcting the field curvature are deviated on a horizontal plane from the center axes of the outer electron beam passage holes in the second type of focus electrode. The electrostatic quadruple lens produces dissimilar intensities for the outer electron beams and for the center electron beam.

Abstract: A color cathode ray tube equipped with an in-line electron gun comprising three cathodes for emitting three electron beams of an in-line arrangement toward a fluorescent screen, and a main lens for focusing the aid three electron beams on the fluorescent screen. The main lens includes a first main lens electrode and a second main lens electrode arranged in a spaced relationship in a direction of an axis of the tube and having different voltages applied thereto.

Abstract: A color cathode ray tube equipped with an in-line electron gun for emitting three electron beams includes a main lens made up of two cylindrical electrodes arranged in a spaced relationship. Each of the electrodes has an opening and having therein a plate electrode with a beam passing area. The electrodes are given different voltages, wherein D and S have values in a region where all of the following inequalities are satisfied; S<D, and 145.5≦55S−20D S being a beam spacing in mm between central axes of the three adjacent electron beams at the main lens, and D being a dimension in mm related to a distance of a center of at least one of the in-line arrangement of the three electron beams to an inner edge of at least one of the two cylindrical electrodes.

Abstract: It is an object to provide a safety cap which is lightweight and excellent in air ventilating ability and waterproofness in rainy weather or the like. The safety cap includes an air hole penetrating inner and outer walls of a cap body, a drainage channel provided along the inner wall of the cap body for discharging water coming into the cap body through the air hole to outside of the cap body, and a vent hole in an upper side of a cross section of the drainage channel perpendicular to the drainage direction. Alternatively the safety cap includes a drainage groove formed in the outer surface of a cap body and having a plurality of vent holes formed in the side walls thereof, wherein the drainage groove is covered with a cover body having air holes and also an edge section of the drainage groove is opened to an outside of the cap body as a drainage hole.

Abstract: A protective cap is formed of a cap body having an inner layer and an outer layer with a clearance therebetween. A number of air holes are provided in the inner and outer layers so that the air holes in the inner layer are displaced from those in the outer layer, and a dam is provided around each of the air holes in the inner layer on a surface thereof facing the outer layer. A spacer formed of a vertical wall contacting the inner and outer layers is provided at least adjacent to each of the air holes of the inner layer. Thus, the protective cap has excellent ventilating capability, a waterproof feature in rain and strength.

Abstract: A color cathode ray tube equipped with an in-line electron gun for emitting three electron beams includes a main lens made up of two cylindrical electrodes arranged in a spaced relationship. Each of the electrodes has an opening and having therein a plate electrode with a beam passing area. The electrodes are given different voltages, wherein D and S have values in a region where all of the following inequalities are satisfied;S.ltoreq.5.0S<D, and145.5.ltoreq.55S-20DS being a beam spacing in mm between central axes of the three adjacent electron beams at the main lens, and D being a dimension in mm related to a distance of a center of at least one of the in-line arrangement of the three electron beams to an inner edge of at least one of the two cylindrical electrodes.

Abstract: A color cathode ray tube equipped with an in-line electron gun for emitting three electron beams includes a main lens made up of two cylindrical electrodes arranged in a spaced relationship. Each of the electrodes has an opening and having therein a plate electrode with a beam passing area. The electrodes are given different voltages, wherein D and S have values in a region where all of the following inequalities are satisfied;S.ltoreq.5.0S<D,and145.5.ltoreq.55S-20DS being a beam spacing in mm between central axes of the three adjacent electron beams at the main lens, and D being a dimension in mm related to a distance of a center of at least one of the in-line arrangement of the three electron beams to an inner edge of at least one of the two cylindrical electrodes.

Abstract: A color cathode ray tube having an in-line type electron gun includes an electron beam generating means having a plurality of electrodes and including at least a cathode for producing electron beams, a first electrode and a second electrode, both constituting control electrodes and arranged in that order, and a heater for heating the cathode; a third electrode, a fourth electrode and a fifth electrode, together constituting a first-stage focusing lens for focusing the three electron beams onto the phosphor screen; and a fifth electrode and a sixth electrode, both forming a second stage focusing lens. Electrical connections are made between the second electrode and the fourth electrode and between the third electrode and the fifth electrode. The first electrode has an aperture 0.

Abstract: A color cathode ray tube comprising in-line electron gun producing three electron beams, said electron gun having main lens comprising two cylindrical electrodes arranged in a spaced relationship in a direction of an axis of said tube, said two cylindrical electrodes being given different voltages, wherein the following inequalities are satisfied,2S+13.66.ltoreq.T.ltoreq.28.14.1.ltoreq.S,S being a beam spacing in mm between central axes of said three adjacent electron beams at said main lens, and T being an outside diameter in mm of a neck portion of a vacuum envelope housing said in-line electron gun.

Abstract: A color cathode ray tube equipped with an in-line electron gun emitting three electron beams includes a main lens made up of two cylindrical electrodes arranged in a spaced relationship. Each of the electrodes has an opening of an elliptic cross section and therein a plate electrode with a beam passing area, and is given different voltages. The following inequalities apply:5.0>S, D>S, and 55S-20D.gtoreq.145.5,S is a beam spacing between adjacent electron beams, and D is the smaller dimension of either a diameter in a direction perpendicular to the in-line arrangement of three electron beams of the cross section of the opposing ends of the two cylindrical electrodes or twice the distance between a center of a side electron beam and an inner edge in a direction of the in-line arrangement of the three electron beams of the cross section of the opposing edge of the two cylindrical electrodes.

Abstract: A color cathode ray tube equipped with an in-line electron gun includes a main lens made up of two cylindrical electrodes arranged in a spaced relationship. Each of the electrodes has an opening and having therein a plate electrode with a beam passing area. The electrodes are given different voltages, wherein the D and S values are in the region where all of the following inequalities are satisfied;5.0>S,D>S, and55S-20D.gtoreq.145.5S being a beam spacing between central axes of adjacent electron beams, and D being a diameter in a direction perpendicular to an in-line arrangement of the electron beams, of the cross section of an opening at opposing ends of the electrodes.

Abstract: An electron gun has one first-type electron lens in the focusing electrode which changes the cross-sectional shape of the electron beam into a nonaxisymmetric shape with increase in the degree of the electron beam deflection by applying a first voltage varying in synchronism with deflection, and one second-type axisymmetric electron lens in the focusing electrode which weakens the lens power with increase in the degree of the electron beam deflection by applying a second voltage increasing with the degree of deflection.