JPH0731490Y2 - Electrostatic deflection type cathode ray tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an electrostatic deflection type cathode ray tube (hereinafter referred to as CRT) used in an oscilloscope, a storage scope and the like.

[Prior Art] As shown in FIG. 5, a conventional CRT for observation has an electron gun 2 and a pair of vertical deflection bodies (deflection plates) 3 and 4 in an outer enclosure 1 made of a glass tube. A vertical deflection system 5, a horizontal deflection system 8 including a pair of horizontal deflectors (deflection plates) 6 and 7, a screen (not shown), and optionally a post-acceleration electrode and a scanning magnifying lens (not shown). And). The pair of vertical deflectors 3 and 4 are connected to the pair of side pins 11 and 12 by the pair of lead wires 9 and 10, respectively, and the pair of horizontal deflector 6 and 7 are connected to the pair of side pins by the pair of lead wires 13 and 14. It is connected to 15 and 16, respectively. Each side pin
11, 12, 15, and 16 are planted in the outer enclosure 1 so that they can be connected to the outside. The pair of vertical deflectors 3 and 4 are opposed to each other with the electron beam passage interposed therebetween, and deflects the electron beam in the vertical direction (first direction) in response to the signal to be measured. A pair of horizontal deflecting bodies 6 and 7 of a horizontal deflecting system 8 disposed adjacent to the vertical deflecting system 5 are disposed so as to face each other with an electron beam passage interposed therebetween, and the electron beam is horizontally directed (second direction) in response to a sweep signal. Bias towards. In another conventional CRT, as shown in FIG. 6, the pair of vertical deflectors 3 and 4 is a stem pin 1 of a stem 17.
8 and 19 are connected by lead wires 9 and 10, respectively, and the pair of horizontal deflectors 6 and 7 are connected to stem pins 20 and 21 by a pair of lead wires 13 and 14, respectively.

[Problems to be Solved by the Invention] By the way, a measured signal of about 0 to several hundred MHz is applied to the vertical deflectors 3 and 4, and a sweep signal of about several MHz is applied to the horizontal deflectors 6 and 7. It When a high-frequency signal is applied to the vertical deflection system 5, the high-frequency signal interferes with the horizontal deflection system due to capacitive and / or inductive coupling in the CRT tube and in the drive circuit to distort the waveform on the tube surface.

Therefore, the object of the present invention is to provide a first deflection system (vertical deflection system).
Another object of the present invention is to provide a CRT capable of eliminating or reducing the interference with the second deflection system (horizontal deflection system).

[Means for Solving the Problems] The present invention for achieving the above-mentioned object includes an electron beam
A first deflecting system (for example, a vertical deflecting system) for deflecting in the direction of, and a pair of deflecting bodies arranged to face each other across the electron beam passage, and a second deflecting body perpendicular to the first direction. Second arranged to deflect the electron beam in a direction
And a pair of lead wires for connecting the pair of deflecting bodies of the second deflecting system to external connection pins (stem pins, side pins, etc.). , The portions of the pair of lead wires near the first deflection system are closer to each other and are arranged in parallel with each other with a narrower interval than the portion other than the portion near the first deflection system, and the vicinity of the pair of lead wires. The present invention relates to an electrostatic deflection type cathode ray tube, wherein distances between one and the other of the portions and the first deflection system are set to be substantially equal to each other.

Further, as described in claim 2, it is desirable that the pair of lead wires be capacitively coupled to each other via a high dielectric constant object.

[Operation] The pair of lead wires is kept at a substantially equal distance from the first deflection system in the vicinity of the first deflection system. Therefore, the amplitude and phase of the interference signal penetrating one and the other of the pair of lead wires from the first deflection system are substantially equal. Therefore, the interference signal is canceled in the second deflection system, and the waveform distortion does not occur on the tube surface. Also, since the pair of lead wires are close to each other in the close approach portion, the lead wires are capacitively coupled with each other, and a canceling action of the interference signal occurs here.

In the second aspect, since the pair of lead wires are capacitively coupled via the high-dielectric-constant object, the capacitive coupling between the two becomes strong, and the canceling action of the interference signal can be satisfactorily obtained.

First Embodiment Next, referring to FIG. 1, a first embodiment of the present invention will be described.
Explain CRT. This CRT has an electron gun 2, a vertical deflection system 5 composed of a pair of vertical deflection bodies (vertical deflection plates) 3 and 4, and a pair of horizontal deflection bodies (horizontal deflection bodies A horizontal deflection system 8 including deflection plates 6 and 7, a fluorescent screen (not shown), a post-acceleration electrode (not shown), and a scanning magnifying lens (not shown) are arranged.

The pair of vertical deflectors 3 and 4 are connected to the pins 18 and 19 of the stem 17 by a pair of lead wires 9 and 10, respectively. The pair of horizontal deflection plates 6 and 7 are connected to the stem pins 20 and 21 by the pair of lead wires 13 and 14. Lead wire 1 of the horizontal deflection system for the stem pins 20 and 21 of the CRT shown in FIG.
The electrical connection of 3 and 14 is substantially the same as that of the conventional example shown in FIG. 10, but the pair of lead wires 13 and 14 have portions 22 and 23 which are close to each other. This closer part 22,
Reference numeral 23 is 3 mm or less, which is narrower than the mutual interval (5 mm or more) of other portions, and is provided in the vicinity of the vertical deflection system 5.

The distances of the mutually approaching portions 22, 23 of the pair of lead wires 13, 14 to the vertical deflection system 5 are substantially equal to each other. As a result, the amplitude and phase of the interference signal entering the mutually approaching portions 22 and 23 from the vertical deflection system 5 are almost equal. When interference signals of the same amplitude and the same phase are applied to the pair of horizontal deflectors 6 and 7, they cancel each other and waveform distortion does not occur on the tube surface. Further, in FIG. 1, since the pair of lead wires 13 and 14 are close to the portions 22 and 23, the degree of capacitive and inductive coupling between them becomes large, and the lead wire 13 penetrates into one lead wire 13. The interference signal and the interference signal penetrating the other lead wire 14 cancel each other. It should be noted that it is not preferable in terms of assembly and connection that the pair of lead wires 13 and 14 are close to each other at all parts.
Therefore, it is desirable to bring the lead wires 13 and 14 close to each other only near the vertical deflection system 5.

[Second Embodiment] Next, referring to FIG. 2, a second embodiment of the present invention will be described.
Explain CRT. However, in FIG. 2 and FIG. 4 which will be described later, parts that are substantially the same as those in FIG. 1 are assigned the same reference numerals and explanations thereof are omitted.

In the CRT of the second embodiment shown in FIGS. 2 and 3, the pair of lead wires 13 and 14 are covered with a glass insulator 28 having a dielectric constant larger than that of air or vacuum in the vicinity of the vertical deflection system 5. ing. In this way, the pair of lead wires 13,
When the high dielectric constant insulator 28 is interposed between the pair of lead wires 13, the pair of lead wires 13 and 14 are capacitively coupled to each other, and it is possible to cancel an interference signal based on the vertical deflection system.

[Modification] The present invention is not limited to the above-described embodiment, and the following modifications are possible, for example.

(1) As shown in FIG. 4, in a case where a pair of lead wires 13 and 14 are connected to the side pins 15 and 16, a high dielectric constant insulator 28 is connected to the side wires 15 and 16 as shown in FIG. You may arrange | position between each other.

(2) In FIGS. 2 and 4, a pair of lead wires 1
3 and 14 are brought close to each other as shown in FIG.
A high dielectric constant insulator 28 may be provided.

(3) The present invention can be applied to the case where the vertical deflection system 5 is a traveling wave type deflection system.

[Effects of the Invention] As described above, according to the present invention, the second deflection system of the first deflection system is used.
The interference with the deflection system can be easily reduced.

[Brief description of drawings]

1 is a perspective view showing a part of a CRT according to the first embodiment of the present invention, FIG. 2 is a perspective view showing a part of a CRT according to the second embodiment, and FIG. 3 is a lead shown in FIG. FIG. 4 is a perspective view showing a part of another modified CRT, FIG. 5 is a perspective view showing a part of a conventional CRT, and FIG. 3 is a perspective view showing a part of the CRT of FIG. 2 ... Electron gun, 3,4 ... Vertical deflector, 5 ... Vertical deflector, 6,7 ... Horizontal deflector, 8 ... Horizontal deflector, 9, 10 ...
Lead wire, 13,14 ...... Lead wire, 18,19,20,21 ...... pin.

Claims (2)

[Scope of utility model registration request] 1. A first deflecting system for deflecting an electron beam in a first direction, and a pair of deflecting bodies arranged to face each other with an electron beam passage interposed therebetween. A second deflection system arranged to deflect the electron beam in a second direction at a right angle, and a pair of leads for connecting the pair of deflectors of the second deflection system to an external connection pin. In the electrostatic deflection type cathode ray tube, the portions of the pair of lead wires in the vicinity of the first deflection system are closer to each other with a narrower interval than portions other than the vicinity portion, and An electrostatic deflection type cathode ray tube, wherein the electrostatic deflection type cathode ray tubes are arranged in parallel, and distances between one and the other of the pair of lead wires in the vicinity thereof and the first deflection system are set to be substantially equal to each other. 2. A first deflecting system for deflecting an electron beam in a first direction, and a pair of deflecting bodies arranged to face each other across a passage of the electron beam. A second deflection system arranged to deflect the electron beam in a second direction at a right angle, and a pair of leads for connecting the pair of deflectors of the second deflection system to an external connection pin. In the electrostatic deflection type cathode ray tube, the portions of the pair of lead wires in the vicinity of the first deflection system are mutually capacitive via a high dielectric constant object having a relative dielectric constant larger than vacuum. An electrostatic deflection type cathode ray tube characterized by being connected.