JPS581502B2 - tv station satsuzou sochi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a television imaging device, and more particularly to an imaging device that reduces the delay time of photoelectric signals.

Generally, an imaging device is configured as shown in FIG.

That is, in the figure, first, in the image pickup tube, a face plate 2 is disposed at one end of an envelope 1, and a transparent conductive film 3 and a photoconductive film 4 are sequentially laminated on the inner surface of the face plate 2.

Note that the envelope 1 and the face plate 2 are made of an opaque sealing metal 5.
It is sealed by.

Further, the transparent conductive film 3 is electrically connected to the signal electrode 6,
Inside the envelope 1, an electron gun 7 is arranged separated from the face plate 2 by a predetermined distance.

The electron gun 7 is composed of a cathode, a control electrode, an accelerating electrode, and a focusing electrode (not shown).

Further, a coil structure 8 is arranged around the outer periphery of the image pickup tube.

In such a configuration, light rays from the subject that are incident through the face plate 2 are converted into a charge pattern by the photoconductive film 4.

On the other hand, the electron beam from the electron gun 7 scans the photoconductive film 4, thereby charging and discharging the charge pattern, so that a photoelectric signal is extracted from the signal electrode 6.

In this case, there is a time lapse after a light beam from the subject to be imaged is incident on the face plate 2 until a photoelectric signal based on this light beam is generated, that is, a rise delay, and after the incidence of this light beam is stopped, a photoelectric signal based on this light beam is generated. It is desirable that the time elapsed until the signal disappears, that is, the falling delay, be short in order to faithfully reproduce the image.

Normally, the rise and fall delays described above are indicated by the number of saturation values reached in several television scans after the incident change of the light beam.

On the other hand, as photoconductive image pickup tubes, the types called Plumbicon (trade name), which has PbO as its main component, and Sachicon (trade name), which has Se-Te as its main component, have excellent imaging quality, so they are usually used. It is often used in broadcast cameras.

Even in these types of photoconductive image pickup tubes, there is a delay in the rise and fall of the photoelectric signal, which poses a problem in faithfully reproducing images.

Here, the rise and fall delays tend to be large when the photoelectric signal current is small, and small when it is large.

Therefore, in general, bias light, that is, uniform light, is irradiated onto the face plate 2 to improve the level of the light rays of the object and to increase the photoelectric signal current to reduce the above-mentioned delay.

Of course, this obtained photoelectric signal current includes the bias light signal, so another signal processing circuit subtracts this component signal to obtain an accurate television signal.

Conventionally, an optical system for combining the bias light with the light beam projected from the subject onto the imaging surface via the imaging lens is configured as follows.

That is, a three-tube color camera usually has a structure in which color separation is performed using a half mirror, and the distance between the half mirror and the imaging surface is set to be relatively long.

Therefore, a reflector is placed in between, and the light reflected by the reflector from another light source is irradiated onto the effective imaging surface of the face plate to create a bias light, and this light and the light beam projected onto the imaging surface are combined. be.

However, in the case of a C-mount imaging lens, the distance from the lens mounting flange surface to the surface of the face plate is only a few millimeters, and it is extremely difficult to insert an optical system for introducing bias light such as the above-mentioned reflector in between, which poses manufacturing problems. There is.

Conventionally, as a structure of an optical system that supplies other bias light, a method has been proposed in which light from a heater of an image pickup tube is introduced into the face plate as bias light.

In this method, the bias light is adjusted by adjusting the supply voltage of the heater.

However, adjusting the supply voltage of the heater in this way is not preferable in terms of imaging operation.

Therefore, this method is not general-purpose and is a special product, which has disadvantages in terms of production adjustment and cost.

Therefore, the present invention makes it possible to easily supply bias light even in a lens mounting system such as a C-mount where the distance from the lens mounting flange surface to the imaging surface is only a few millimeters. This solves the problem.

In order to achieve such an object, the present invention includes a bias light mechanism to introduce light from the end of the envelope on the side of the face plate, and allows the light introduced from this mechanism to pass through the gap between the face plate and the electron gun. This method supplies bias light by irradiating the face plate with the light, and will be described in detail below using examples.

The structure of the imaging device is as explained in FIG. The electron gun 7 is arranged with a slight gap between the two.

Therefore, when light is introduced from the face plate side end 13 of the envelope 1 and irradiated onto the photoconductive film of the face plate 2 through the gap g between the face plate 2 and the electron gun 7, this light is , will be superimposed on the light rays from the subject and act as a bias light.

In consideration of this point, 20 shown in FIG. Enclosure 1
The coil structure 8 is disposed at the face plate side end 13 of the envelope 1 through the end of the coil structure 8 disposed around the face plate, and the light from the light source 21 is introduced into the face plate side end 13.

The coil structure 8 includes a deflection coil 10 surrounded by a coil frame 9, a focusing coil 11, and these coils 10,
The light transmitting pipe 20 is composed of a coil magnetic shielding material 12 surrounding the coil structure 8, one end of the coil magnetic shielding material 12 of the coil structure 8, one end of the deflection coil 10 and the focusing coil 11, and a coil magnetic shielding material 12 surrounding the coil structure 8. Between the side wall 91 of the frame 9 and
It extends through the bottom 92 of the coil frame 9 to a portion corresponding to the face plate side end 13 of the envelope 1 .

According to such a configuration, the light from the light source 21 disposed at one end of the original transmitting pipe 20 is well irradiated onto the face plate side end 13 of the envelope 1 through the original transmitting pipe 20, 13, passes through the gap g between the face plate 1 and the electron gun 7, and is irradiated onto the photoconductive film side of the face plate 2.

Therefore, this light acts as a bias light on the face plate 2, and has the effect of shortening the rise and fall delays of the signal.

Therefore, according to the present invention, it is advantageous to use a structure in which light is irradiated from the front surface of the face plate 2, which simplifies manufacturing.Moreover, since the light from the heater of the image pickup tube is not used as the light source of the bias light, it is advantageous in terms of production adjustment and cost. becomes.

Here, in this embodiment, one light transmitting pipe 20 is provided and light is introduced into the face plate 2 from one location of the envelope 1. However, the present invention is not limited to this, and the light transmitting pipe 20 is Two or more light beams 20 may be provided to supply light to the face plate 2 from two or more locations.

In the case where light is introduced from a plurality of locations, the introduction locations may be determined from the viewpoint of uniformly irradiating the light onto the face plate 2.

In addition, as another method for further improving the uniformity of the bias light, an envelope 1 corresponding to the light transmitting pipe 20 may be used.
For example, the inner and outer surfaces of the end portion 13 may be polished with abrasive sand to form a grain, etched using a hydrofluoric acid solution, or coated with a diffusive substance, or even grooved. This end 1 is cut by making a notch.
3 is a light-diffusing part, and this light-diffusing end part 1
3, the light may be diffused and irradiated onto the face plate 2.

In this way, the light is not concentrated and supplied to the face plate 2, but is diffused and supplied to the face plate 2, so that the uniformity of the bias light on the face plate 2 is further improved.

Further, in this embodiment, the portion of the light transmitting pipe 20 through which the coil structure 8 is passed is explained as using the gap between the end portions of the coils 10 and 11 and the side wall 91 of the coil frame 9, but the present invention However, the present invention is not limited to this, and it is also possible to use a part that substantially avoids the coil structure 8 and other electrical and magnetic structures and to pass the light transmitting pipe from this part, or to combine it with the coil frame 9. The light transmission path may be formed by embedding the light transmission pipe 20 in the coil frame 9 using a soft material such as resin.

In other words, the light transmitting pipe 20 may be arranged through any route, as long as it can introduce light from the end 13 of the face plate 1 of the envelope 1.

Furthermore, in this embodiment, the light transmitting pipe 20 has been described as penetrating the bottom part 92 of the coil frame 9, but the present invention is not limited to this, and the bottom part 92 of the frame 9 can be made transparent or translucent. By introducing the above-mentioned light transmitting pipe 20 to the bottom surface, the light from the pipe 20 is transmitted to the bottom 9.
Alternatively, the liquid may be supplied to the face plate side end portion 13 so as to be transmitted from 2.

Further, in this embodiment, it goes without saying that the tip of the light transmitting pipe 20 may be configured to abut against the end portion 13 on the side of the face plate of the envelope 1.

As explained above, the television imaging device according to the present invention is provided with a bias light mechanism, and has a configuration in which the bias light from this mechanism is introduced from the face plate side end of the envelope of the image pickup tube. This is advantageous in terms of manufacturing since it is not necessary to use a very limited space, and it is advantageous in terms of production adjustment and cost since an independent light source is used as the light source for the bias light.

Also, since the bias light can be irradiated uniformly,
Not only can the fall delay be significantly reduced,
This has the great effect of uniformly shortening these delays over the entire imaging plane.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway sectional view showing an example of a conventional imaging device;
FIG. 2 is a partially cutaway sectional view showing an embodiment of the imaging device according to the present invention. 1... Envelope, 2... Face plate, 3...
...Transparent conductive film, 4...Photoconductive film, 5...
...Sealing metal, 5...Signal electrode, 7...
...electron gun, 8...coil structure, 20...
Light transmitting pipe, 21... Light source.

Claims (1)

[Scope of Claims] 1. A television image pickup tube having a face plate disposed at the end of the envelope and an electron gun assembly disposed at a predetermined distance from the face plate, and a coil surrounding the envelope. Light is transmitted through the structure and the edge of the face plate of the envelope, and this light is irradiated onto the photoelectric conversion surface of the face plate from the back side of the source power conversion surface to shorten the rise and fall delay times of the photoelectric signal. a bias light mechanism, wherein light from a light source of the bias light mechanism is introduced into an end portion of the envelope on the side of the face plate using a light transmitting pipe. 2. In the television imaging device according to claim 1, the end portion of the envelope on the side of the face plate is a light-diffusing portion, and light introduced into this portion is diffused and reaches the photoelectric conversion surface of the face plate. A television imaging device characterized by uniform irradiation.