JPH0536769B2 - - Google Patents

Description

Detailed Description of the Invention (Technical Field) The present invention relates to an apparatus for observing a visible image and an image formed by a specific wavelength component in a superimposed manner, and more specifically, for example, an object image that can be observed with the naked eye and an apparatus for observing an image formed by a specific wavelength component. The present invention relates to an apparatus for superimposing a visible image and an image formed by a specific wavelength component, which is suitable for superimposing an invisible image formed by a specific wavelength component.

(Prior Art) An image intensifier is known as a device that multiplies a non-visible image and observes it as a visible image.

FIG. 1 is a block diagram showing a conventional image intensifier. In the figure, 1 is an object to be observed, and an image of this object is transmitted to the photocathode 5 of an image intensifier tube 3 by an objective lens 2.
is formed. Photoelectrons corresponding to the image generated by the photocathode 5 are focused on the surface of the microchannel plate 7 by an electron lens 6 and are multiplied.

A fluorescent image (visible image) is formed on the fluorescent screen 8 by the multiplied electrons. This visible image is observed by an observer through the eyepiece lens 9.

Image intensifiers are usually invisible to the eye from 10 ^-6 to
An image under illuminance of about 10 ^-3 Lux can be intensified and made visible.

Furthermore, by selecting a photocathode, an image formed by non-visible light components can be converted into a visible image.

Consider the case where an image ranging from visible to ultraviolet is formed by visible light illumination and the radiation of the object itself. This is the image of the fuel rods of a nuclear reactor stored and illuminated in a pool, which will be described later.

At this time, the following two methods can be considered for observing the ultraviolet image.

Ultraviolet images can be observed using an image intensifier that is not sensitive to illumination light.

If the illumination light is turned off and an image intensifier tube sensitive to visible and ultraviolet light is used, an ultraviolet image can be observed.

If it is necessary to observe under illumination, the above shall be followed.

At this time, if part of the object is emitting light, there is a problem in that it is not possible to determine where in the overall image the ultraviolet light emitting point corresponds.

In such a case, it would be convenient if, for example, an object image that can be observed with the naked eye and an invisible image formed by a specific wavelength component generated by the object can be observed in a superimposed manner. Furthermore, if it is possible to superimpose an image of an object that can be observed with the naked eye and an invisible image formed by specific wavelength components generated by the object, it will be possible to identify objects and contribute to the elucidation of various physical phenomena. No such device has been developed at present.

(Objective of the Invention) The main object of the present invention is to provide an apparatus for superimposing a visible image and an image formed by a specific wavelength component caused by an observed object causing the visible image.

(Means for Solving the Problems) In order to achieve the above object, an apparatus for superimposing a visible image and an image formed by a specific wavelength component according to the present invention has the following features: an image intensifier tube that multiplies and converts a visible image; an objective lens system that forms an image containing the specific wavelength component generated by the observed object on a photocathode of the image intensifier tube; and an image intensifier tube that enhances the image. an eyepiece optical system for observing an image visualized by the specific wavelength component; and an incident light amount adjusting means, the eyepiece optical system having an aperture to adjust the light amount of the visible image of the object to be observed, and concentrically arranged with the same magnification. It consists of a direct visible image observation optical system that overlaps with the luminance approximately equal to the .

The direct visible image observation optical system includes a second eyepiece optical system located on the optical axis of the eyepiece optical system that reflects the light from the objective lens of the optical system with a first half mirror to observe the visible image of the image intensifier tube. It is configured to be re-reflected by a half mirror and overlapped with an image formed by a specific wavelength component.

The incident light amount adjusting means of the direct visible image observation optical system compares the light transmitted through the first half mirror and the light reflected by the second half mirror with a diaphragm provided in the optical system. The control circuit may also include a control circuit that drives the diaphragm so that the amount of light that passes through the first half mirror follows the amount of light that is reflected by the second half mirror.

Still another device for observing a visible image according to the present invention and an image formed by a specific wavelength component in a superimposed manner includes an image intensifier tube that multiplies the image formed by a specific wavelength component and converts it into a visible image. , an objective lens system that forms an image containing the specific wavelength component generated by the observed object on the photocathode of the image intensifier tube; a television system including a television image pickup tube and a reproduction device; an imaging optical system that projects a visible image of the image intensifier tube onto a photocathode of the television image pickup tube; It consists of a direct visible image observation optical system that adjusts the amount of light in the visible images with an aperture and overlaps them at the same magnification.

(Example) Hereinafter, the present invention will be described in more detail with reference to the drawings and the like.

FIG. 2 is a schematic representation of a first embodiment of the device according to the invention. Components common to those of the apparatus described in connection with FIG. 1 are given the same numerals. The purpose of this embodiment is to observe images of nuclear reactor fuel rods stored and illuminated in a pool, and an image intensifier tube 3 sensitive to ultraviolet light is used. The window of the image intensifier tube 3 is made of MgF ₂ and the photocathode is a CsTe photocathode. The basic structure and operation of the image intensifier tube are the same as described in FIG.

The direct visible image observation optical system 10 has telescope-type lens systems 10b and 10c, and is supported so that its optical axis is parallel to the optical axes of the image intensifier tube 3 and the objective lens.

A diaphragm 13 is arranged in this direct visible image observation optical system 10 .

A visible image based on the ultraviolet image formed on the fluorescent screen 8 of the image intensifier tube 3 is transmitted through the half mirror and the eyepiece lens 1.
2, observed by an observer.

On the other hand, the light transmitted through the telescope-type lens systems 10b and 10c of the direct visible image observation optical system 10 is reflected by the total reflection mirror 10d, and further reflected by the half mirror 1.
1 and observed by the observer through the eyepiece lens 12. The magnification of the direct visible image observation optical system 10 (including the eyepiece 12) is
It is set equal to the magnification of the objective lens 2, image intensifier tube 3, and eyepiece lens 12.

Thereby, the observer can observe the directly visible image of the observed object 1 and the image caused by ultraviolet rays in a superimposed manner. Thereby, it is possible to directly observe from which part of the object to be observed 1 the ultraviolet rays are emitted.

Note that the aperture 13 is provided to adjust the brightness of the two images so that they do not differ significantly.

FIG. 3 is a schematic representation of a second embodiment of the device according to the invention. Parts common to those of the apparatus described in connection with FIG. 2 are given the same numerals.

This device is similar to the aperture 1 of the first embodiment device.
3 is automatically adjusted.

The first half mirror 30 and the second half mirror 36 of the light transmitted through the above-mentioned telescope type lens systems 10b and 10c of the direct visible image observation optical system 10
As a result, the reflected direct image is observed through the eyepiece lens 12. A visible image caused by ultraviolet rays formed on the fluorescent screen of the image intensifier tube 3 is transmitted to the second half mirror 3.
6 and an eyepiece 12. Thereby, the observer can observe the directly visible image of the object 1 to be observed and the image caused by ultraviolet rays in a superimposed manner as in the first embodiment described above.

The light transmitted through the first half mirror 30 and the second half mirror 36 is detected by the light detection 3 of the aperture control circuit 35.
1 and 32, respectively.

The outputs of the photodetectors 31 and 32 are amplified by amplifiers 35a and 35b, respectively.

The outputs of the amplifiers 35a and 35b correspond to the brightness of the direct image and the brightness of the fluorescent screen of the image intensifier tube 3, respectively.

The output of each amplifier 35a and amplifier 35b is
The signals are compared by a comparator 35c and amplified by an amplifier 35d. Based on the output of the amplifier 35d, the aperture drive circuit 34 drives the aperture 13 so that the amount of light transmitted through the first half mirror 30 follows the amount of light reflected by the second half mirror 36.

Thereby, the observer can observe the directly visible image of the object 1 to be observed and the image caused by ultraviolet rays superimposed at appropriate brightness.

FIG. 4 is a block diagram showing a third embodiment of the apparatus according to the invention. Components common to those of the apparatus described in connection with FIG. 3 are given the same numerals and their explanations will be omitted.

In this embodiment, a direct visible image and a visible image caused by ultraviolet rays are sent to a remote location for observation using a television system. Suitable when it is dangerous for the observer to approach the observed object.

The image caused by the ultraviolet light transmitted through the second half mirror 36 and the directly visible image reflected by this half mirror 36 are formed on the photocathode of the imaging tube 41 of the imaging device by the lens 40 of the imaging optical system. . The output of this image pickup tube 41 is sent from a transmitting device 42 to a receiving device 43.

The viewer can observe the superimposed image caused by the ultraviolet rays and the directly visible image using the television monitor on the receiving device 43 side.

The transmitting device 42 and the receiving device may be coupled by a closed circuit, or by a line such as radio waves or light.

(Effects of the Invention) As described above, according to the device according to the present invention,
For example, it is suitable for superimposing an object image that can be observed with the naked eye and an invisible image formed by a specific wavelength component generated by the object, and superimposing a visible image and an image formed by a specific wavelength component. can do.

It can be used to solve various problems that were considered impossible until now. Application examples will be described below.

○ Analysis of electrical discharges that occur on the surfaces of glass and insulators In connection with ultra-high voltage power transmission, elucidating the mechanism of electrical discharges that travel on the surfaces of insulators has become an important issue.

It is assumed that the initiation of a discharge begins with a local breakdown, which usually propagates along the surface and progresses to a general discharge.

Ultraviolet light is an effective clue for observing this initial state.

Due to safety concerns, it is difficult to conduct this experiment in the dark, so it is necessary to experiment with visible lighting.

Furthermore, there is a strong desire to see the entire insulator as a visible image in order to see which part of the overall structure of the insulator becomes the discharge starting point.

In order to achieve this, it is desirable to separately detect the ultraviolet image that is actually desired to be viewed and the overall visible image, and then combine them after processing such as multiplication.

FIG. 5 schematically depicts this experiment.

As shown in Figure A, no ultraviolet image associated with the discharge is observed, but with the ultraviolet image intensifier as described above, it can be made into a visible image as shown in Figure B. By superimposing this image and the directly visible image (C in the same figure) as shown in D in the same figure, the discharge can be clearly understood in relation to the insulator.

○ Simultaneous observation of Thierenkov light and fuel rods in a spent nuclear fuel storage pool Thierenkov light is generated when charged particles (electrons, etc.) move through matter. The wavelength is widely distributed from ultraviolet to infrared, but the amount is large in the ultraviolet region. When detecting this light in the dark, a detector sensitive from ultraviolet to visible light may be used.

For safety reasons, lights cannot be turned off in spent nuclear fuel storage pools. There is also a strong desire to simultaneously observe a visible image of a fuel rod or its container and a beam of light caused by Thierenkov light.

According to the device of the embodiment, the above requirements can be completely satisfied.

○ Observation of aurora images from satellites By capturing ultraviolet aurora images with an ultraviolet image intensifier and superimposing them with the overall image of the Earth captured by a visible optical system, it is possible to understand the entire image. The devices of each of the embodiments of the present invention can be used for this observation.

○ Identification of fingerprints There are attempts to use special reagents (which adhere to fingerprints and emit ultraviolet fluorescence) to detect fingerprints left on banknotes. The devices of each of the embodiments of the present invention can be used for this identification.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the configuration of an image intensifier.
FIG. 2 is a block diagram showing a first embodiment of the apparatus according to the invention. FIG. 3 is a block diagram showing a second embodiment of the apparatus according to the invention. FIG. 4 is a block diagram showing a third embodiment of the apparatus according to the invention. FIG. 5 is a schematic diagram for explaining an example of the use of the device according to the invention. 1...object to be observed, 2...objective lens, 3...
Image intensifier, 10...Direct visible image observation optical system, 11
...Half mirror, 12...Eyepiece, 13...
... Aperture, 30 ... First half mirror, 34 ... Aperture drive circuit, 35 ... Aperture control circuit, 36 ... Second half mirror, 40 ... Lens of imaging optical system,
41... Image pickup tube, 42... Transmitting device, 43... Receiving device.

Claims (1)

[Scope of Claims] 1. An image intensifier tube that multiplies an image formed by a specific wavelength component and converts it into a visible image; an objective lens system formed on the photocathode; an eyepiece optical system for observing a visualized image of the specific wavelength component intensified by the image intensifier; The light intensity of the visible image of the observed object is adjusted with an aperture, and the visible image formed by the direct visible image observation optical system and the image formed by the specific wavelength component are observed by superimposing them concentrically at the same magnification and with approximately equal brightness. Device. 2. The direct visible image observation optical system has a first half mirror located on the optical axis of the eyepiece optical system that reflects the light from the objective lens of the optical system with a first half mirror to observe the visible image of the image intensifier tube. 2. An apparatus for observing a visible image and an image formed by a specific wavelength component in a superimposed manner as claimed in claim 1, wherein the visible image and the image formed by the specific wavelength component are superimposed on each other by being re-reflected by two half mirrors. 3. The incident light amount adjusting means of the direct visible image observation optical system includes a diaphragm provided in this optical system and the first
The light transmitted through the half mirror is compared with the light reflected by the second half mirror, so that the amount of light transmitted through the first half mirror follows the amount of light reflected by the second half mirror. An apparatus for observing a visible image and an image formed by a specific wavelength component in a superimposed manner according to claim 2, which comprises a control circuit for driving said aperture. 4. An image intensifier tube that multiplies an image formed by a specific wavelength component and converts it into a visible image, and an image including the specific wavelength component generated by the object to be observed is formed on a photocathode of the image intensifier tube. a television system including a television image pickup tube and a playback device; an imaging optical system that projects a visible image of the image intensifier tube onto a photocathode of a television image pickup tube of the television system; The visible image is composed of a direct visible image observation optical system that adjusts the amount of light of the visible image of the object to be observed using an aperture and superimposes it at the same magnification on the visible image of the image intensifier tube formed on the photocathode of the image pickup tube. A device that superimposes and observes images formed by specific wavelength components.