JPS5832448B2 - Method for manufacturing face plate structure for image pickup tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a face plate structure for an image pickup tube, and more particularly to a method of manufacturing a face plate structure incorporating a stripe filter.

In general, a face plate structure in which the light selectivity of a striped filter is determined by an organic dye is widely known, but since both the dye carrier and the dye have low heat resistance, the surface of the stripe filter cannot be used as the face plate structure of an image pickup tube. It is covered with thin glass.

FIG. 1 is a sectional view of a main part of an example of an image pickup tube, and FIG. 2 is a perspective view of a main part of an example of a face plate structure thereof.

In these figures, this image pickup tube has a face plate 1 made of a transparent material such as glass, a color separation stripe filter (hereinafter referred to as a stripe filter) 2 made of an organic dye, and a thin plate glass 4 attached via an adhesive 3. , a transparent conductive film (hereinafter referred to as NESA film) 5, and a photoconductive film 6 are sequentially deposited, and this face plate 1
is sealed to the open end of an outer tube 10 containing an electron gun 9 using a signal electrode 8 to which indium 7 is attached, and the inside of the outer tube 10 is evacuated to a vacuum.

The light 12 from the object 11 forms an image on the photoconductive film 6 through the optical lens 13, and a charge pattern image corresponding to the image of the object 11 is formed on the photoconductive film 6, and the electron beam from the electron gun 9 forms an image on the photoconductive film 6. 14 is focused and scanned on the surface of the photoconductive film 6 by a magnetic field created by a deflection coil 15 and a focusing coil 16 arranged around the outer circumference of the outer tube 10, and the charge pattern is converted into an electric current. The signal is extracted as an electrical signal from the signal electrode 8 through the signal electrode 8.

In the image pickup tube constructed as described above, the target is manufactured by the steps shown in cross-sectional views in FIG. 3a=d.

That is, in these figures, as shown in figure a, a stripe filter 2 is formed by a well-known method on a light-transmitting face plate 1 with a thickness of about 2.5 m, and a stripe filter 2 is formed on two sides of the stripe filter of this face plate 1. &o manufactured by Corning, Inc., known as micro sheet glass with a thickness of about 50 to 100 μm
2 ii Glass (hereinafter referred to as microsheet glass) 17 is bonded together using, for example, an epoxy adhesive 3 (see the same figure).

Thereafter, as shown in Figure C, the microsheet glass 17 is polished, for example, to a polishing line K with a plate thickness of approximately 20 to 3011 m, through rough polishing, center polishing, and finishing polishing steps as shown in Figure d. A desired face plate structure is manufactured by forming a thin glass plate 4 on the surface.

However, in the method for manufacturing a face plate structure according to the above method, it is sufficient that the thin glass 4 is bonded parallel to the upper surface of the striped filter 2 and the polishing proceeds parallel to the bonded surface. In order to prevent scratches and polish with high efficiency, polishing with a soft polishing plate made of felt or artificial leather will result in
Normally, polishing of the peripheral portion of the thin glass plate 4 progresses rapidly as shown by the dotted line in FIG. 4, which is called a peripheral sag.

As a result, the peripheral portion of the thin glass 4 becomes abnormally thin and easily damaged, or in extreme cases, the thin glass 4 disappears, or three layers of adhesive are exposed on the surface of the stripe filter 2. This has had disadvantages such as the purpose of serving as a support substrate for protecting the surface of the substrate cannot be achieved.

Therefore, the present invention has been made in order to eliminate the above-mentioned conventional drawbacks, and is to manufacture a face plate structure for an image pickup tube in which the peripheral part of the thin glass can maintain a sufficient thickness even after the above-mentioned polishing method is applied. The purpose is to provide a method.

In order to achieve such an object, the present invention has a thin plate glass having a thickness of 30 to 100 μm on a face plate on which a stripe filter is formed, and which already has a curved surface before bonding, so that the bonding surface side thereof has a concave shape. The face plate is arranged so that the adhesive is thinner at the peripheral area than at the center area of the face plate.

The method for manufacturing a face plate structure according to the present invention will be described in detail below with reference to the drawings.

First, before describing Examples, microsheet glass will be described in order to facilitate understanding of the present invention.

That is, a thin glass sheet having a thickness of about 50 to 100 .mu.m is a glass sheet produced by a pulling method called microsheet glass, which is inexpensive.

However, this glass plate has a relatively large surface undulation, and in particular has a corrugated plate shape that extends in the pulling direction of the glass plate and has undulations in the width direction.

The pitch of this waveform is about 2 to 10 CrIL, so when the microsheet glass is cut to be used for the above-mentioned bonding, it becomes a single glass substrate, and when looking at the side surface, it has either a convex or concave shape. have.

Furthermore, it is extremely rare for a single glass substrate to have a mixture of unevenness and depressions, and in such a case, it can be approximately regarded as a flat plate.

Furthermore, when attaching a thin glass sheet of about 50 to 100 μm to a stripe filter, the most desirable thing is to use a flat thin glass sheet, but flat thin glass sheets of this thickness should be polished. It is much more expensive than thin sheet glass produced by the pulling method.

Next, the present invention will be explained in detail.

FIGS. 5a and 5b are cross-sectional process diagrams of main parts for explaining an example of a method for manufacturing a face plate structure for an image pickup tube according to the present invention,
Since the same symbols as in FIGS. 1 to 3 represent the same elements, their explanations will be omitted.

In these figures, first, as shown in figure a, the other side of the face plate 1, on which the stripe filter 2 is adhered and formed, is attracted to the vacuum chuck 18 and adhered to a spinner (not shown).

Next, as shown in the figure, an appropriate amount of liquid epoxy adhesive 3 is dropped onto the striped filter 2 formed on the face plate 1, and a microsheet having a thickness of 30 to 100 μm is placed above it. The thin glass sheets 19 formed by cutting out glass are stacked so that their adhesive surfaces have a concave shape and no air bubbles enter the adhesive 3, and the adhesive 3 is applied using the weight of the thin glass sheets 19 or other auxiliary means.
After the adhesive 3 is spread over almost the entire surface of the face plate 1, the vacuum chuck 17 is rotated at high speed, and the adhesive 3 is spread thinly by centrifugal force and fixed.

After that, the adhesive 3 is solidified.

In this case, the thin glass plate 19 having a concave shape on the side of the adhesive 3 is bent and attracted to the side of the adhesive 3 due to centrifugal force, so that the adhesive 3 around the face plate 1 becomes thinner than the center and is bonded and solidified.

Here, as an example, when bonding a face plate with a diameter of 26mvt and a thin sheet of glass, a thin sheet of glass with a thickness of about 30 to 50 μm will have a concave shape on the adhesive side.
If it is rotated for about 3 minutes at a rotation speed of about 00 ORPM, the peripheral part will be sufficiently adsorbed by the adhesive, but with a thin sheet of glass that is arranged in a convex shape on the adhesive side, the adhesive in the peripheral part is weaker than in the center of the face plate. It is not possible to reduce the average thickness of the agent.

The same results were obtained with thin sheets of glass as thick as 70-90 μm by spin bonding at 6000-8000 RPM.

That is, when bonding the thin glass 19 using the centrifugal bonding method, by attaching it so that it has a concave shape on the bonding surface side, the thickness of the adhesive 3 at the peripheral portion of the face plate 1 can be made thinner than at the center portion. did it.

In this case, the thickness of the adhesive 3 is 5 to 10μ at the center.
In the peripheral part of m1, it is about 2 to 8 μm.

Thereafter, while rotating the vacuum chuck 18 as shown in Figure C, the top surface of the thin glass 18 is polished to a polishing line K using a soft polishing board made of felt, artificial leather, etc., as shown in Figure d. In this way, a striped filter-equipped face plate structure including a thin glass plate 4 having a thickness of approximately 20 to 30 μm is obtained.

According to such a manufacturing method, the peripheral part of the thin glass 4 causes peripheral sagging and the degree of flatness deteriorates, but the thin glass 4
A strong face plate structure can be obtained without the adhesive 3 becoming excessively thin at the periphery, causing damage, peeling, or exposing the adhesive 3.

In addition, a polished surface that is sufficiently smooth and free from scratches can be easily obtained as a support substrate for the photoelectric conversion surface of the image pickup tube.

As explained above, according to the method of manufacturing a face plate structure for an image pickup tube according to the present invention, a thin plate glass serving as a support substrate for a photoelectric conversion surface can be obtained with high quality and high reliability, and a face plate structure can be obtained at a low cost. Excellent effects can be obtained.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a main part showing an example of a conventional image pickup tube, Fig. 2 is a perspective view of a main part showing the face plate structure of Fig. 1, and Fig. 3 a =
d is a cross-sectional process diagram of a main part showing a conventional manufacturing method of a face plate structure for an image pickup tube, FIG. FIG. 3 is a cross-sectional process diagram of a main part showing an example of a method for manufacturing a pipe face plate structure. 1... Face plate, 2... Color separation stripe filter (strive filter), 3... Adhesive, 4... Thin glass, 18... ...Vacuum chuck, 19...Thin glass.

Claims (1)

[Claims] 1. A method for manufacturing a face plate structure for an image pickup tube in which a color-separating stripe filter, an adhesive, and a thin glass are sequentially laminated on a transparent face plate, wherein the face plate has a flat face plate on which the color-separating stripe filter is formed. 30~100μ on top
A thin glass sheet having a thickness of m and already having a curved surface before bonding is arranged so that the adhesive surface side has a concave shape, so that the thin glass sheet is coated with adhesive more on the outer periphery of the face plate than on the center part of the face plate. 1. A method for manufacturing a thin face plate for an image pickup tube, comprising: adhering the thin glass so that the thickness thereof is reduced, and polishing the convex surface of the thin glass to further reduce the thickness of the thin glass.