JPS58139B2 - Method for manufacturing face plate for image pickup tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a method of manufacturing a face plate for an image pickup tube.

Various methods have been proposed for obtaining color television signals using a single image pickup tube, such as a three-electrode method and a phase separation method.

Among these systems, the structure near the imaging face plate of a color television camera image pickup tube incorporating a striped color filter in the three-electrode system is as shown in FIG.

That is, a striped color filter 2 is formed on an optically polished transparent substrate 1 by diffusing dye into an inorganic multilayer film or an organic film.

Next, a glass thin film 3 having a thickness of several μm to several tens of μm
is bonded via an adhesive 4 to a transparent substrate 1 on which striped color filters 2 are formed.

A striped transparent electrode 5 is provided on the electron gun side of the glass thin film 3 (not shown) in order to extract color signals corresponding to each color light.
Further, a photoconductive film 6 is formed on the striped transparent electrode 5.

In manufacturing this image pickup tube, the transparent substrate 1 on which the striped color filter 2 to the photoconductive film 6 are formed is placed in a glass tube 7 in which various electron gun electrodes (not shown) prepared in advance are enclosed. Completed by joining.

This bonding is performed by pressure bonding using a soft metal 8 such as indium.

As is clear from FIG. 1, the soft metal 8 is connected to the transparent electrode 5, from which a signal current is extracted from the metal ring 9.
to the television camera circuit (not shown), or
Or sent via lead 10 to the television camera circuit.

Next, a conventional method of manufacturing a face plate for an image pickup tube related to the present invention will be described.

As shown in FIG. 2, first, a striped color filter 2 is formed on a transparent substrate 1.

A glass thin film 3 having a thickness of a few micrometers to several tens of micrometers
A striped transparent electrode 5 is formed on top, and this is glued with adhesive 4.
The striped color filters 2 are bonded to the transparent substrate 1 on which the striped color filters 2 are formed.

The striped transparent electrodes 5 formed on the glass thin film 3 can be formed directly on the glass thin film 3 with a thickness of several μm to several tens of μm, or the striped transparent electrodes can be formed on a glass substrate having a certain thickness. After that, the glass substrate is polished to a thickness of several μm to several tens of μm. However, in any case, the glass thin film 3 with a thickness of several μm to several tens of μm has extremely weak mechanical strength and must be handled carefully. Very poor quality.

Furthermore, since the glass thin film 3 is bent when bonded to the transparent substrate 1, the flatness after bonding is extremely poor, and when assembled into a color image pickup tube, the image quality is significantly degraded.

The present invention solves these drawbacks, provides high-quality color television images, and facilitates the production of face plates for color image pickup tubes.

FIG. 3 shows an embodiment of the invention.

First of all, rather than what we are trying to complete as a face plate for an image pickup tube,
A striped transparent electrode 5 is formed on a glass substrate 12-1 having an outer diameter of, for example, 0.5 mm or more and a comb thickness of 1 mrn or more (FIG. 3a).

Next, a glass substrate 12 on which striped transparent electrodes 5 are formed
-1 is temporarily bonded to a smooth plate 14 using an adhesive 13 such as beeswax that can be easily removed by heat or solvent (FIG. 3b).

Thereafter, the glass substrate 12-1 is polished to a predetermined thickness of several μm by, for example, a mechanical polishing method to form a glass thin film 12-2 (FIG. 3C).

Next, the transparent substrate 15 on which the striped color filter 2 is formed is bonded to the glass thin film 12-2 polished to a predetermined thickness using a transparent and stable adhesive 16, such as epoxy resin. do.

(Figure 3d). Next, in order to remove the protrusion of the adhesive 16 to the side surface and the minute cracks around the glass thin film 12-2 to be removed by polishing it to a thickness of several micrometers to tens of micrometers, the outer periphery is cut to a predetermined area. Finish to the dimensions (Fig. 3 e)
.

Finally, the adhesive 13 such as beeswax is removed using heat or an organic solvent, and the smooth plate 14 is removed from the glass thin film 12-2 to expose the striped transparent electrodes 5, completing the image pickup tube face plate.

As explained above, according to the present invention, by improving the flatness of the image pickup tube face plate, particularly the glass thin film, a high quality color television image can be obtained, and the easily damaged glass thin film on which striped transparent electrodes are formed can be obtained. This makes it easier to handle in the manufacturing process and facilitates the production of face plates for image pickup tubes.

Although the present invention has been described with reference to a photoconductive surface type image pickup tube, it is clear that it can also be used in an image pickup tube having a photoelectron emitting surface.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the vicinity of a face plate for an image pickup tube incorporating a striped color filter, FIG. 2 is a process diagram showing a method of manufacturing a face plate for an image pickup tube by a conventional method, and FIG. Process diagram showing the manufacturing method, 5 varnish drive-shaped transparent electrode, 12-1 = glass substrate, 12-2 glass thin film, 13: adhesive, 14: smooth plate, 15: transparent substrate, 1
6: Adhesive.

Claims (1)

[Claims] 1. Temporarily bonding a glass substrate larger than a predetermined outer diameter on which a transparent electrode is formed to a smooth plate and polishing a thin film to a predetermined thickness, and temporarily bonding a glass thin film made by this thin film polishing to the smooth plate. A step of bonding the transparent substrate to a transparent substrate larger than a predetermined outer dimension on which a color filter is to be formed, and a step of cutting a crack portion on the outer periphery of the smooth plate, the glass thin film, and the transparent substrate while they are still bonded. ,
1. A method of manufacturing a face plate for an image pickup tube, the method comprising obtaining a face plate for an image pickup tube having a predetermined size and no defects.