CN1259226A

CN1259226A - Color picture tube having an inline electron gun

Info

Publication number: CN1259226A
Application number: CN98805715A
Authority: CN
Inventors: O·P·特林切洛; M·A·汤姆森; R·L·巴宾; R·H·米勒
Original assignee: Thomson Tubes and Displays SA
Current assignee: Thomson Tubes and Displays SA
Priority date: 1997-07-04
Filing date: 1998-06-30
Publication date: 2000-07-05
Anticipated expiration: 2018-06-30
Also published as: JP2002510430A; KR20010014361A; EP0889500B1; EP0889500A1; KR100360534B1; WO1999001884A1; DE69724942D1; AU8283098A; CN1124635C; TW398009B

Abstract

The present invention relates to a color picture tube (10) having a viewing screen (22), and an electrode gun (26) within a neck (14) of the tube for generating and directing three in line electron beams, a center beam and two side beams, toward the screen. The electron gun includes a plurality of electrodes including a focus electrode (G5). The tube neck is adapted for receipt of a surrounding scan velocity modulation coil (54, 56) at a location thereon. The focus electrode includes two spaced parts (44, 46) that are electrically connected and adapted for connection to the same focus voltage (VFOCUS). The space (45) between the parts is surrounded by the neck location for the coil.

Description

Chromoscope with in line gun

The present invention relates to improved chromoscope, particularly have the pipe of the in line gun that comprises the crack focusing electrode with in line gun.

For chromoscope, the definition of image depends on whether have little electron-beam point size on tube fluorescent screen.In this pipe, electron gun produces three beams must be focused to tuftlet point simultaneously on phosphor screen electron beam.Knownly utilize the coil on the neck can realize both scan velocity modulation (SVM).The SVM coil is a two-pole device, and this device makes the electron beam horizontal deflection with generation vertical magnetic field is set.This coil improves the image quality of pipe by the horizontal deflection speed of modulated electron beam.Function as vision signal drives the SVM coil.Because video frequencies increases, and for example be increased to VGA and SVGA frequency from the NTSC frequency, thereby the SVM coil should work in correspondingly under the higher frequency.These upper frequencies cause magnetic field to change rapidly.According to Faraday's law of induction, change of flux will produce inner closed loop current path in any conductor.In addition, Lenz's law has stipulated that the eddy current of induction will produce the induction magnetic flux that the resistance in-field changes, thereby weakens the magnetic field size that arrives electron beam.These size of current depend on that magnetic flux is the rate of change of frequency.The circuit that the weakening of this magnetic field needs higher-wattage or the coil of higher sensitivity cause undesirable higher cost thus.

The present invention relates to have the chromoscope of a phosphor screen and an electron gun in neck, described used in electron gun is that central electron beam and two bundles are the three beams I-shaped electron beam of side electron beam and with its described phosphor screen that leads to produce a branch of.Described electron gun comprises a plurality of electrodes that comprise focusing electrode.Neck is suitable for installing the scan velocity modulation coil around thereon.Focusing electrode comprises two two separate sections that are electrically connected and are suitable for being connected to identical focus voltage.Interval between two separate sections is surrounded by the tube neck branch that is used for coil.This provides non-vortex zone at interval, thereby strengthens the magnetic field on the electron beam of putting on produced.

In the accompanying drawing:

Fig. 1 is a plane graph of implementing the chromoscope that localized axial of the present invention dissects.

Fig. 2 is the end view that is positioned at neck and Fig. 1 electron gun of SVM coil is arranged on neck.

Fig. 3 is a schematic diagram of showing Fig. 2 electron gun of electron gun electrodes electrical connection.

Fig. 4 divides the front view of relative G5B electrode part one side with the G5T electrode part in the electron gun of Fig. 2.

Fig. 5 is the front view that divides relative G5B electrode part one side in another electron gun with the G5T electrode part.

Fig. 1 illustrates the rectangle chromoscope 10 with glass shell 11, and wherein shell 11 comprises rectangle screen dish 12 and the neck 14 that is connected by rectangular cone 15.Cone 15 has the internal conductive coating (not shown) that extends to neck 14 from anode button 16.Screen dish 12 comprises watches panel 18 and periphery flange or sidewall 20, and sidewall 20 is by melted glass 17 and cone 15 sealings.Tricolour phosphor screen 22 is disposed at panel 18 inner surfaces.Phosphor screen 22 preferably has the bar shaped phosphor screen by one group of phosphor strip of arranging of ternary, and each tlv triple comprises phosphor strip in three looks of all kinds.In addition, phosphor screen also can be a dot fluorescent screen.With the predetermined space of relative fluorescence screen 22 the porous color selection utmost point or shadow mask 24 are installed removably with conventional method.The electron gun 26 of with dashed lines signal medially is assemblied in the neck 14 among Fig. 1, in order to produce three-beam electron-beam and to arrive phosphor screen 22 along convergence path guiding electron beam by shadow mask 24.

The pipe of Fig. 1 is designed to use under the situation that has external magnetic deflection system (not shown), and this deflection system is assemblied on the pipe near the junction of cone and neck.When being energized, deflection system makes three-beam electron-beam be subjected to the effect in magnetic field, causes that electron beam scans phosphor screen 22 horizontally and vertically along rectangular raster.

Be shown specifically electron gun 26 among Fig. 2,3 and 4.Electron gun 26 comprises three row formula negative electrodes 34 (only illustrating) that separate, control gate 36 (G1), screen 38 (G2), accelerating grid electrode 40 (G3), plate electrode 42 (G4), separated into two parts 44 (G5B) and the focusing electrode (G5) of 46 (G5T) and last electrodes 48 (G6).Each electrode in G1 to the G6 electrode all has the aperture that allows three-beam electron-beam to pass through therein.Form static main focusing lens in the electron gun 26 by the part of facing mutually of G5T electrode part 46 and G6 electrode 48.Form G5B electrode 44 and G5T electrode 46 by two

part

44B and 44T and 46B and 46T respectively.

All electrodes in the electron gun 26 all are connected in two directly or indirectly and thoroughly do away with on edge pole 50 and 52.Pole is preferably glass, heats this pole and it is pressed on the claw type thing that stretches out from electrode, so embed this claw type thing in pole.

What illustrate on the neck 14 in Fig. 2 is two scanning modulation (SVM) coils 54 and 56.Each coil is roughly rectangle and is configured as with the neck circumferential shapes and matches.Each coil also is included in neck top and bottom big center respect to one another window.The SVM coil of even now has been used to have on the pipe of electron gun of fixed-focus voltage, but the inventor finds, by additional spacer 45 is set in electron gun, allow the SVM field to act on the electron beam, can strengthen of the effect of SVM coil these pipes in the mode that is not blocked.45 permissions are not suffered the loss that generation caused because of eddy current in the electrode by the fast-changing magnetic flux arrival electron beam of SVM coil generation at interval.By the G5 focusing electrode axially being divided into two parts, promptly G5B electrode part 44 and G5T electrode part 46 can form this additional spacer 45.Coil should center on this interval between the electrode part 44 and 46, but as shown in Figure 2, this interval preferably should be arranged at more near the axial centre of coil rather than their end part.

The electrical connection of electrode in the electron gun shown in Fig. 3 26.The G1 electrode grounding.G2 and G4 are connected to each other and are connected to G2 voltage V simultaneously _G2, G3, G5B and G5T all are connected with each other and are connected to fixed-focus voltage V _FOCUS, G6 and anode voltage V _ANODEConnect.

In electron gun 26, the aperture 47 that two electrode parts 44 and 46 the part 44T that faces mutually and 46B comprise single prolongation respectively is shown in the part 44T among Fig. 4.Two electrode parts 44 and 46 remote part 44B and 46T comprise three

apertures

60,62 and 64 that pass through for three-beam electron-beam respectively respectively, shown in part 44T among Fig. 4.Fig. 5 illustrates another embodiment of part 44T and 46B, wherein casts aside label with band respectively and represents identical entry.This embodiment illustrates the size that how to change all apertures in electrode part 44 and 46 particular value with obtained performance.In this part of another embodiment shown in Figure 5, bigger expansion aperture 47 ' be arranged among the part 44T ', three bigger apertures 60 ', 62 ' and 64 ' be arranged among the part 44B '.

Provide the one group of electrode gap that is used for electron gun 26 in the following table.

Table 1

Interval between negative electrode and the G1=0.003 " (0.076mm) ^*

Interval between G1 and the G2=0.009 " (0.229mm)

Interval between G2 and the G3=0.030 " (0.762mm)

Interval between G3 and the G4=0.050 " (1.270mm)

Interval between G4 and the G5B=0.050 " (1.270mm)

Interval between G5B and the G5T=0.070 " (1.778mm)

Interval between G5T and the G6=0.050 " (1.270mm)

^*Under working temperature

Claims

1. a chromoscope (10), have phosphor screen (22) and the electron gun (26) in the neck (14) of described pipe, described used in electron gun is that central electron beam and two bundles are the three beams I-shaped electron beam of side electron beam and with its described phosphor screen that leads to produce a branch of, described electron gun comprises a plurality of electrodes that comprise focusing electrode (G5), and described focusing electrode comprises two electrical connections and is suitable for being connected to identical focus voltage (V _FOCUS) separate section (44,46,44 '), wherein, (44T 46B) comprises three apertures (60 that supply three-beam electron-beam to pass through respectively to the part of facing mutually of described two separate sections of described focusing electrode, 62,64,60 ', 62 ', 64 '), and in described two separate sections at least one, described three apertures are from constituting the single expansion aperture (47 that passes through for three-beam electron-beam, 47 ') forward position part (43,43 ') be provided with backward.

2. a chromoscope (10), have phosphor screen (22) and the electron gun (26) in the neck (14) of described pipe, described used in electron gun is that central electron beam and two bundles are the three beams I-shaped electron beam of side electron beam and with its described phosphor screen that leads to produce a branch of, described electron gun comprises a plurality of electrodes that comprise focusing electrode (G5), scan velocity modulation coil (54,56) center on described neck in the focusing electrode position, and described focusing electrode comprises two electrical connections and is suitable for being connected to identical focus voltage (V _FOCUS) two separate sections (44,46,44 ').

3. chromoscope as claimed in claim 2 is characterized in that, described two separate sections (44 of described focusing electrode (G5), 46,44 ') comprise three apertures (60,62 that pass through for three-beam electron-beams respectively in the face of part mutually, 64,60 ', 62 ', 64 '), and at least one in described two separate sections, described three apertures are provided with backward from the forward position part (43,43 ') that constitutes the single expansion aperture (47,47 ') that passes through for three-beam electron-beam.