JPH0654190U - Electronic image converter - Google Patents

Abstract

(57) [Abstract] [Purpose] To prevent the recording of bright spots, which are false signals generated when observing ultra-low-speed signals, in electronic image conversion devices. A means for generating an electron beam, a fluorescent screen on which the electron beam is projected, an optical fiber plate in close contact with the fluorescent screen, and a solid-state imaging device in close contact with or close to the optical fiber plate, A conductive thin film that is arranged between the output end face of the optical fiber plate and the light receiving surface of the solid-state imaging device and has a light-transmitting property capable of transmitting light having a wavelength that can pass through the optical fiber plate;
A glass plate portion supporting the optical fiber plate is provided, and a conductive layer is formed on the non-vacuum side outer wall of the glass plate portion. [Effect] It is possible to prevent the recording of bright spots, which are false signals generated during the observation of ultra-low speed signals.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an electronic image conversion device for converting a display on a phosphor screen into electric information by a solid-state image sensor, and particularly to a device suitable for measuring an electric waveform.

[0002]

[Prior art]

 First, the configuration and operation of a conventional electronic image conversion device will be briefly described with reference to FIG. An electron gun 7 composed of a cathode 2, a control grid 3, an accelerating electrode 4, a focusing electrode 5 and an astigmatic electrode 6 is arranged in the vacuum outer wall 1, and a deflecting means 10 comprising a vertical deflecting plate 8 and a horizontal deflecting plate 9 is arranged. Is further provided with a post-acceleration electrode 11 and a fluorescent screen 12, and an optical fiber plate 14 in which a transparent conductive film 16 is formed in close contact with the output end face is supported on a glass plate portion 13 via a frit (powdered glass) 15. Then, the solid-state imaging device 17 is brought into close contact with the fluorescent screen 12 and the transparent conductive film 16 is brought close to or in close contact with the optical fiber plate 14 in which the transparent conductive film 16 is closely formed on the output end face.

This device displays information such as electrical waveforms on the phosphor screen 12, transmits the displayed information to the solid-state image sensor 17 using the optical fiber plate 14 with low optical transmission loss, and further transmits the optical fiber plate 14 This is a device for preventing local electrification of the optical fiber plate 14 by the transparent conductive film 16 formed in close contact with the output end face of the device and converting it into a recording or electrical signal without impairing the quality of the displayed information.

[0004]

[Problems to be solved by the device]

 However, in the above-described conventional electronic image conversion apparatus, when an ultralow-speed signal having a period of several seconds or more is to be observed, the bright spot, which is a false signal, is recorded together with the ultralow-speed signal to be observed originally. Observed. The bright spots, which are false signals, not only impair the image quality, but can also become a major obstacle when performing image processing such as thinning processing and image analysis. The bright spot recording is considered to occur due to the following reasons.

In this type of electronic image conversion apparatus, in order to observe an ultra-low speed signal with a period of several seconds or more, a solid-state image sensor is used at 1/30 second per frame, as is well known in the video field. The output signal read from 17 is subjected to A / D conversion, ORed with a frame memory (not shown), stored in the frame memory, and this process is repeated for an arbitrary time.

However, as is well known in the field of cathode ray tubes, a high voltage of 10 to 20 KV is applied to the rear accelerating electrode 11 in order to cause the fluorescent screen 12 to emit light with high brightness, and is a glass that is an insulator. The non-vacuum outer walls of the plate portion 13 and the frit 15 are unevenly charged. The non-vacuum outer wall of the glass plate part 13 and the frit 15 which is the insulator is not always uniformly charged, and the surface condition or contact of the non-vacuum outer wall of the glass plate part 13 and the frit 15 is not always stable. It is considered that the charging and discharging will be repeated intermittently, depending on the atmosphere in which it is used. The discharged charges are transmitted through the non-vacuum outer wall of the electronic image conversion device and flow into the solid-state image sensor 17. Alternatively, it is considered that the bright spots are recorded by the electromagnetic waves generated during discharge flowing into the solid-state imaging device 17.

Therefore, an object of the present invention is to provide an electronic image conversion device capable of preventing the recording of bright spots which are false signals even when observing an ultra-low speed signal having a period of several seconds or more. .

[0008]

[Means for Solving the Problems]

 In order to achieve this object, the electronic image conversion device of the present invention comprises means for generating an electron beam, a fluorescent screen on which the electron beam is projected, an optical fiber plate in close contact with the fluorescent screen, It is arranged between the solid-state imaging device that is in close contact with or close to the optical fiber plate, and the output end face of the optical fiber plate and the light-receiving surface of the solid-state imaging device, and transmits light of a wavelength that can pass through the optical fiber plate. A light-transmitting conductive thin film to be obtained and a glass plate portion supporting the optical fiber plate, and a conductive layer is formed on the non-vacuum side outer wall of the glass plate portion. Is.

[0009]

[Action]

 The conductive layer on the outer wall of the non-vacuum side in the present invention has a function of preventing uneven charging of the glass plate portion and the frit supporting the optical fiber plate, and even when observing an ultra-low speed signal with a period of several seconds or more. It is possible to prevent the recording of bright spots that are false signals.

[0010]

【Example】

 Hereinafter, the present invention will be described in detail with reference to FIGS.

FIG. 1 shows an embodiment of the present invention, and the portions common to those of FIG.

In this embodiment, a conductive layer 18 is formed on the non-vacuum outer wall of the frit 15 and the glass plate portion 13 that supports the optical fiber plate 14. The conductive layer is made of carbon and has a thickness of about 0.1 mm and a sheet resistance of about 5 kΩ / □ and is formed by a spray method. In this apparatus, the electron beam emitted from the electron gun 7 is deflected by the deflecting means 10 and projected on the phosphor screen 12, and information such as a waveform is displayed on the phosphor screen 12. This information is transmitted to the solid-state image sensor 17 by the optical fiber plate 14 and converted into an electric signal.

By the way, in this embodiment, in order to observe an ultra-slow sine wave having a period of 1 sec, an output signal read from the solid-state image pickup device 17 is A / D converted at 1/30 sec per frame, and a frame memory ( (Not shown) and the OR operation, the number of bright spots, which are false signals, stored in the frame memory is significantly reduced as compared with the case where the conductive layer 18 is not provided, and the image quality is significantly improved. The reason why such an effect is obtained is considered to be as follows.

That is, according to the present embodiment, since the conductive layer 18 is formed on the non-vacuum outer wall of the glass plate 13 and the frit 15 supporting the optical fiber plate 14, the non-vacuum outer wall of the glass plate portion 13 and the frit 15 is formed. Is not unevenly charged, and is kept at a uniform potential. Therefore, the discharge of electric charges is less likely to occur on the non-vacuum outer wall of the glass plate portion 13 and the frit 15, and the electric charge is transmitted through the non-vacuum outer wall to flow into the solid-state image sensor 17 or the solid-state image sensor 17. It is thought that this is because the generation of electromagnetic waves during discharge does not occur.

The conductive layer 18 used in this embodiment is not limited to carbon, and as generally known, has a sheet resistance of 10 ⁹ Ω / □ or less, which has an antistatic effect. If so, a similar effect is obtained.

In the second embodiment shown in FIG. 2, the conductive line 19 is connected to the conductive layer 18. The other structure is the same as that of the first embodiment shown in FIG. The conductive line 19 is applied with a potential lower than that of GND or the post-stage acceleration electrode 11. As a result, it becomes possible to discharge the non-vacuum outer wall of the glass plate portion 13 and the frit 15 non-uniformly through the conductive wire 19, and the electric potential of the non-empty outer wall of the glass plate portion 13 and the frit 15 is changed. It can be held more uniformly than in the first embodiment, and the recording of bright spots is further reduced.

[0017]

[Effect of device]

 As described above, it is possible to prevent the recording of bright spots, which are false signals, even when observing an ultra-low-speed signal in which a conductive layer is formed on the glass plate portion supporting the optical fiber plate and the non-vacuum outer wall of the frit.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an electronic image conversion apparatus of the present invention.

FIG. 2 is another embodiment of the present invention.

FIG. 3 is a configuration diagram of a conventional electronic image conversion apparatus.

[Explanation of symbols]

 1 Vacuum Outer Wall 2 Cathode 3 Control Brid 4 Accelerating Electrode 5 Focusing Electrode 6 Astig Electrode 7 Electron Gun 8 Vertical Deflection Plate 9 Horizontal Deflection Plate 10 Deflection Means 11 Later Acceleration Electrode 12 Fluorescent Surface 13 Glass Plate Part 14 Optical Fiber Plate 15 Frit 16 Transparent conductive film 17 Solid-state image sensor 18 Conductive layer 19 Conductive wire

Claims (1)

[Scope of utility model registration request] 1. A means for generating an electron beam, a fluorescent screen on which the electron beam is projected, an optical fiber plate in close contact with the fluorescent screen, and a solid-state image sensor in close contact with or close to the optical fiber plate. , The optical fiber
A conductive thin film, which is disposed between the output end face of the plate and the light-receiving surface of the solid-state image sensor and has a light-transmitting property that allows light having a wavelength that can pass through the optical fiber plate, and the optical fiber plate. An electronic image conversion apparatus comprising: a glass plate portion that supports a glass plate portion;