JPS61110943A - Pickup tube - Google Patents

Abstract

PURPOSE:To support a mesh electrode with vibration resistance with a metal ring through comparatively less welding processes by holding the mesh electrode with the first and second tongue-shaped extrusions extruded inward from the extruded edge of a metal ring and a pair of tongue-shaped extrusions extruded inward from the internal circumferential edge of frame. CONSTITUTION:A metal ring 8 for adjusting lens field has an annular extruded edge 11 at the one aperture end edge and a first and a second tongue-shaped extrusions 12, 13 extruded inward from the extruded edge 11. The metal annular frames 14 stacked through the mesh electrodes 7 are provided with a pair of tongue-shaped extrusions 15, 16 extruded inward so that these are opposed to the first and second tongue-shaped extrusions 12, 13 and the extruded edge 11 and frame 14 are spot-welded in several points in both sides of mesh electrode 7. Thereby, the internal side of circumferential edge is also held by the first and second tongue-shaped extrusions 12, 13 and a pair of tongue-shaped extrusions 15, 16 and the mesh electrode can be supported with vibration resistance on a metal ring with comparatively less welding processes.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an image pickup tube comprising a focusing electrode, a target electrode, and a mesh electrode disposed between the gaps, which are insulated and supported at the tip of the focusing electrode. be.

Conventional technology In an image pickup tube having a photoconductive film type target electrode, 1
．． A mesh electrode disposed between a focusing electrode and a target electrode is insulated and supported at the tip of the focusing electrode. Such an image pickup tube was manufactured by the Japanese Patent Publication No. 39-1586.
As disclosed in Publication No. 5, by applying a potential difference between the focusing electrode and the mesh electrode, not only can the secondary electrons emitted from the mesh electrode be collected by the mesh electrode, but also the secondary electrons emitted from the mesh electrode can be collected by the mesh electrode. By selecting the axial dimension of the metal ring of the generated electron lens, the electric field of the electron lens can be adjusted to an appropriate distribution.

In this way, the mesh electrode is insulated and supported at the tip of the focusing electrode via the metal ring, but the metal ring is provided with an earthquake-resistant structure to prevent microphonic noise from occurring even if mechanical shock is applied from the outside. It is important to support them. A preferred example of an earthquake-resistant support structure for mesh electrodes is disclosed in Japanese Utility Model Publication No. 16759/1983.

According to this support structure, the mesh electrode is sandwiched between the first and second annular frames made of metal plates, and both frames have upper and lower tongues protruding from the inner peripheral edge toward the center. Since the upper tongue-like projections and the lower tongue-like projections face each other and sandwich a part of the inner region of the mesh electrode, the generation of natural vibration is suppressed.

However, if we adopt the procedure of inserting the mesh electrode into the first and second annular frames, welding them together, and then welding them to the metal ring of the mesh electrode support mechanism, not only will the number of welding steps increase, but also the number of welding steps will increase. The metal ring is easily deformed, making it difficult to attach it to the focusing electrode. Also, the first
It is conceivable to omit the metal ring side of the second annular frame to reduce the welding man-hour by half, but in this case, the seismic support function of the mesh electrode will be degraded.

Problems to be Solved by the Invention Therefore, it is an object of the present invention to provide a mesh electrode that is earthquake resistant with a relatively small number of welding steps, compared to a metal ring that supports the mesh electrode and adjusts the lens electric field. An object of the present invention is to provide an image pickup tube that can be supported.

Means for Solving the Problems The present invention provides an imaging method in which a mesh electrode disposed between a focusing electrode and a target electrode is insulated and supported at the tip of the focusing electrode via a metal ring for adjusting a lens electric field. In the tube, an annular plate-shaped projecting edge is integrally formed on one opening edge of the metal ring, and first and second tongue-like projections are provided inwardly projecting from the projecting edge, A metal annular plate-shaped frame stacked on the projecting edge via the mesh electrode is welded to the projecting edge, and a pair of tongue-like protrusions protruding inward from the inner peripheral edge of the frame and the third The mesotu electrode is held between the first and second tongue-like projections.

For this reason, the mesh electrode is not only held at its periphery by the frame on the annular protrusion of the metal ring for adjusting the lens electric field, but also by the first and second tongue-like projections of the former and the pair of tongues of the latter. The inner side of the periphery is also clamped by the shaped projections, making it possible to earthquake-proofly support the mesh electrode on the metal ring with a relatively small number of welding steps.

Embodiment To explain the present invention in more detail with reference to the embodiment shown in the drawings, as shown in FIG. A mesh electrode 7, which has a target electrode made of a transparent conductive film 4 and a photoconductive film 5 on its inner surface, and which is arranged between a focusing electrode 6 and a target electrode, includes a metal ring 8 for adjusting the lens electric field, and a mesh electrode support. It is attached to the tip of the focusing electrode 6 via a metal ring 9 and a ceramic ring 1o.

As shown in FIG. 2, the lens electric field adjusting gold kA ring 8 has an annular protruding edge 11 on one opening edge thereof, and first and second protruding edges projecting inward from the protruding edge 11.
It has a tongue-like process 12.13. Then, a metal annular plate-shaped frame 14 is stacked with mesh electrodes 7 placed thereon, and a frame 14 protrudes inwardly so as to face the first and second tongue-like protrusions 12 and 13. It has a pair of tongue-like protrusions 16, 16, and the projecting edge 11 and the frame 14 are spot-welded at several locations with the mesh electrode 7 sandwiched therebetween.

Since the first and second tongue-shaped protrusions 12, 13 are obtained by cutting and raising the cylindrical portion of the metal ring 80 as shown in FIG. 3, there is no need to weld any special members. but,
Instead of forming the protrusion by such cutting and raising, a small metal piece for the tongue-like protrusion may be attached by welding.

Effects of the Invention Since the present invention is configured as described above, the mesh electrode can be supported on the metal ring for adjusting the lens electric field in a kJB manner with a relatively small number of welding steps, and the effect of suppressing microphonic noise can be achieved at low cost. can be obtained.

[Brief explanation of drawings]

Fig. 1 is a sectional view of the main parts of an image pickup tube embodying the present invention;
The figure is an exploded perspective view of the main part, and FIG. 3 is an enlarged perspective view of a part of the metal ring for adjusting the lens electric field, which is the main part. 5... Photoconductive film, 6... Focusing electrode, 7...
... Menyu electrode, 8 ... Metal ring for lens electric field adjustment, 11 ... Annular plate-shaped ridge, 12
,13. ．． 16゜16... tongue-like process, 14...
····flame. Name of agent: Patent attorney Toshio Nakao and one other name
1 Diagram δ---Ku-reden-Han G-3 Elephant #! , viL 7--Metsu V Koden, Moji δ--1-Synth 1C Kaigomei January 45th edition Vybu. // --- F (J, 蓉hee enter ゛tsuso (1 year old / 2.
/3. /, 5; fG ---i Toyoi & f4-11 frame

Claims (1)

[Claims] In an imaging tube in which a mesh electrode disposed between a focusing electrode and a target electrode is insulated and supported at the tip of the focusing electrode via a metal ring for adjusting a lens electric field, one opening edge of the metal ring integrally has a toric plate-shaped protrusion, and has first and second tongue-like protrusions protruding inward from the protrusion, and is stacked on the protrusion via the mesh electrode. A metal annular plate-shaped frame is welded to the projecting edge, and the mesh is formed by a pair of tongue-like protrusions protruding inwardly from the inner peripheral edge of the frame and the first and second tongue-like protrusions. An imaging tube characterized by having electrodes clamped together.