JPH02215032A - X-ray image intensifier equipped with solid-state pick-up element - Google Patents

Abstract

PURPOSE:To make an image system itself compact by providing an optical fiber plate at an output window, guiding light converted at a fluorescent screen of the output window linearly, connecting a solid-state pick-up element with the injection side, and giving a direct incidence of a transmitted visible light image to be converted into electric signals. CONSTITUTION:Light converted at a fluorescent screen 4 of an output window 3 is guided linearly by an optical fiber plate 12 provided at the output window 3 of an image intensifier main body 11, and a direct incidence of a transmitted visible light image is given by a solid-state pick-up element 14 connected with the optical fiber plate 12 on the injection side to be converted into electric signals. The solid-state pick-up element 14 which is compact and light can thus be disposed very close to the output window 3 of the image intensifier 12 through the optical fiber plate 12. Sizes W, (h) for an image system itself can thus be small to make it compact.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention provides
Related to an X-ray image intensifier with a solid-state imaging device that converts an X-ray transmitted image transmitted through a subject into a visible light image in an X-ray television device used for radiographic inspection, and also captures the image and converts it into an electrical signal. .

[Conventional technology]

In order to convert the transmitted X-ray image transmitted through the subject into a visible light image and to capture the image and convert it into an electrical signal using a conventional X-ray television set, as shown in FIG. An X-ray transmission image of a subject (not shown) enters through the input window 2 of the image intensifier 1 and is converted into a visible light image on the phosphor screen 4 of the output window 3, and this output visible light image is sent to the light distributor. The light emitted from this lens 6a is reflected by a mirror 7 to change its course, and the light is narrowed down by the other lens 6b of the tandem relay lens to be transmitted to a television camera 8. into the image pickup tube of
The television camera 8 captures the incident visible light image and converts it into an electrical signal.

[Problem to be solved by the invention]

However, when using such a conventional X-ray image intensifier 1 and television camera 8, in order to optically connect the X-ray image intensifier 1 and television camera 8, an optical distributor 5 is used. Since the tandem relay lenses 6a, 6b and mirror 7 must be used, the dimensions W and H of the imaging system itself from the X-ray image intensifier 1 to the television camera 8 become large. . Therefore, the weight of the imaging system itself becomes large, and in the fluoroscopic imaging table with an X-ray television, various movements such as vertical movement, back and forth movement, and raising and lowering are sometimes restricted. In order to avoid this, the overall size of the fluoroscopic imaging table had to be increased. Further, the output visible light image from the X-ray image intensifier 1 is as follows.

Due to the effects of light scattering and vignetting caused by the tandem relay lenses 8a, 6b and mirror 7, contrast may deteriorate and light intensity may vary, resulting in a decrease in the quality of the resulting image.

Therefore, one object of the present invention is to provide an X-ray image intensifier with a solid-state image sensor that can solve such problems.

[Means to solve problems]

In order to achieve the above object, an X-ray image intensifier with a solid-state image sensor according to the present invention is provided.

The X-ray transmitted image that has passed through the object enters through the input window and is converted into a visible light image on the output window's phosphor screen.The light converted by the phosphor screen goes straight to the output window of the image intensifier body. An optical fiber plate is provided to guide the optical fiber, and a solid-state image sensor is attached to the exit side of the optical fiber plate to input the transmitted visible light image and convert it into an electrical signal.

Further, the optical fiber plate is bonded to the inner surface of the output window of the image intensifier body, and its entrance surface is coated with phosphor, and the solid-state image sensor is bonded to the outer surface of the output window. Good too.

Furthermore, the output window portion of the image intensifier body is constructed of an optical fiber plate, the entrance surface of which is coated with a phosphor, and a solid-state image sensor is bonded to the exit surface of the optical fiber plate. Good too.

Furthermore, a multi-channel plate for multiplying light may be interposed between the exit surface of the optical fiber plate and the solid-state image sensor.

It is effective to shift the electrode voltages of the input phosphor screen and the output phosphor screen of the image intensifier main body, and set the electrode voltage on the output phosphor screen side to near the O potential.

[For production]

The X-ray image intensifier with a solid-state image sensor configured in this way uses an optical fiber plate provided at the output window of the image intensifier body to linearly transmit light converted by the phosphor screen of the output window. The transmitted visible light image is directly incident on the solid-state image sensor connected to the exit side of the optical fiber plate and converted into an electrical signal. Therefore, a small and lightweight solid-state imaging device can be placed extremely close to the image intensifier body, which allows the imaging system itself to be made smaller and improves image quality by eliminating the need for other optical systems such as lenses. be able to.

(Example) Hereinafter, an example of the present invention will be described in detail based on the accompanying drawings.

FIG. 1 is an explanatory front view showing an embodiment of an X-ray image intensifier 10 with a solid-state image sensor according to the present invention.

In FIG. 1, the image intensifier body 11
converts an X-ray transmission image transmitted through a subject (not shown) into a visible light image.

An X-ray transmission image of the subject enters through the input window 2, is converted into an optical image by an internal fluorescent screen, and then converted into photoelectrons by a photocathode (not shown), and these photoelectrons are transferred to an internal focusing electrode (not shown). ), the photoelectrons are focused toward the output window 3, and when the photoelectrons hit the fluorescent screen 4 of the output window 3 and emit light, they are converted into a visible light image and emitted from the output window 3.

The output window 3 of the image intensifier body 11 is provided with an optical fiber plate 12 (see FIG. 2). This optical fiber plate 12 guides the converted light straight from the incident side to the exit side, and is formed into a thin plate shape by bundling optical fibers, as shown in FIG. 2.

It is bonded and fixed to the inner surface of the output window 3. and,
On the entrance surface of this optical fiber plate 12.

A phosphor 13 is applied, thereby forming a phosphor screen 4 shown in FIG.

Further, a solid-state image sensor 14 is bonded and fixed to the exit side of the optical fiber plate 12.

This solid-state image sensor 14 is connected to the optical fiber plate 12.
It converts the visible light image transmitted through the incident light into an electrical signal, and consists of a semiconductor array of elements that have photoelectric conversion and amplification functions, such as MOS FETs or CODs (charge coupled devices), as shown in Figure 2. As shown in FIG. 2, the optical fiber plate 12 is directly bonded to the outer surface of the output window 3 of the image intensifier main body 11 at a position corresponding to the optical fiber plate 12. In this solid-state image sensor 14,
A camera body 22 for an image sensor is attached.

Note that since this camera body 22 is only an electronic circuit that processes electrical signals input from the solid-state image pickup device 14, the lead wires may be extended and provided at a different position.

As a result, the small and lightweight solid-state image sensor 14 is placed extremely close to the output window 3 of the image intensifier body 11 via the optical fiber plate 12, and the dimensions of the image system itself are Since h becomes smaller, miniaturization is achieved.

FIG. 3 is an enlarged sectional view of a main part showing a second embodiment of the present invention. In this embodiment, the output window 3 of the image intensifier body 11 is constructed of the optical fiber plate 12 itself, and the entrance surface of the optical fiber plate 12 is coated with a phosphor 13, as shown in FIG. A phosphor screen 4 is formed, and a solid-state image sensor 14 is directly bonded to the exit surface of the optical fiber plate 12. In this case, since the solid-state image sensor 14 is bonded directly to the exit surface of the optical fiber plate 12, it is not affected by light scattering etc. due to the output window 3 made of glass or the like in FIG. You can get the image.

FIG. 4 is an enlarged sectional view of a main part showing a third embodiment of the present invention. This embodiment differs from the embodiment shown in FIG. 3 in that a multi-channel plate 15 is interposed between the exit surface of the optical fiber plate 12 and the solid-state image sensor 14 to multiply and output the incident light. It is. In this case, even if the visible light image sent from the optical fiber plate 12 is an image with low illuminance, the light can be multiplied and sent to the solid-state image sensor 14, making it possible to perform imaging with high sensitivity. can.

FIG. 5 is an enlarged sectional view showing a fourth embodiment of the present invention. In this embodiment, the image intensifier body 11
By shifting the electrode voltages of the input and output phosphor screens,
The electrode voltage on the output phosphor screen side is set near 0 potential (earth potential). That is, in FIG. 5, the potential difference between the input phosphor screen 16 on the input window 2 side and the output phosphor screen 13 on the output window 3 side (same as the coated surface of the phosphor 13 in FIGS. 2 to 4) is , generally requires about 25 to 30 KV, and conventional X-ray image intensifier 1
In this case, the input phosphor screen 16 side was grounded to have a potential near 0, and a high voltage of about 25 to 30 KV was applied to the output phosphor screen 13 side. However, in the present invention, FIGS.
As explained in FIG. 4, the optical fiber plate 12 and the solid-state image sensor 14 are located on the output window 3 side of the image intensifier body 11, that is, on the output fluorescent screen 13 side.
is directly provided, so if a high voltage of 25 to 30 KV is applied to the output phosphor screen 13 side as in the conventional case, the optical fiber plate 12 will not be able to withstand the high voltage, and will also be prevented from being affected by the electric field and discharge due to static electricity. There is a possibility that the generated noise may enter the solid-state image sensor 14. Therefore, in the present invention, a negative high voltage of -25 to -30 KV is applied from the high voltage power supply 17 to the electrode 18 on the side of the input phosphor screen 16, and the electrode 19 on the side of the output phosphor screen 13 is grounded to bring the voltage near 0. It is set to . In FIG. 5, reference numeral 20 indicates a focusing electrode, and reference numeral 21 indicates a shield case in which the image intensifier main body 11 is housed. In the embodiment shown in FIG. 5, the input phosphor screen 16 is
It is necessary to strengthen the insulation of the voltage supply line that supplies high voltage to the side electrodes 18 and the middle focusing electrode 20. According to this embodiment, the potential near the output phosphor screen 13 is almost zero. , it is possible to prevent damage to the optical fiber plate 12 provided at that location, and also to prevent noise from entering the solid-state image sensor 14 . Therefore, high quality images can be obtained.

Note that in one or more of the explanations, the optical fiber plate 12
Although optical fibers are bundled to form, for example, a board shape, the present invention is not limited to this.

A tapered fiber may be used to enlarge or reduce the image, or it may be bent at an arbitrary angle to refract the optical path.

〔Effect of the invention〕

Since the present invention is configured as described above, the optical fiber plate 12 provided at the output window 3 of the image intensifier body 11 straightly guides the light converted by the fluorescent screen 4 of the output window 3. .

The solid-state imaging device 14 bonded to the exit side of the optical fiber plate 12 allows the transmitted visible light image to be directly incident thereon and converted into an electrical signal. Therefore, the small and lightweight solid-state image sensor 14 can be placed extremely close to the output window 3 of the image intensifier main body 11 via the optical fiber plate 12, and the dimensions w of the image system itself are The size can be reduced by reducing h. As a result, the entire apparatus such as a fluoroscopic imaging stand with an X-ray television can be downsized. Also.

Since there is no intervening optical system such as lenses or mirrors other than the optical fiber plate 12, images can be captured by the solid-state image sensor 14 without being affected by light scattering or aperture axis as in the conventional case, improving the image quality of the obtained image. be able to.

[Brief explanation of the drawing]

FIG. 1 is an explanatory front view showing an embodiment of an X-ray image intensifier with a solid-state image sensor according to the present invention, and FIG. 2 is an enlarged cross-sectional view of main parts showing the structure of the output window of the image intensifier main body. 3 and 4 are enlarged sectional views of essential parts showing a second embodiment or a third embodiment of the present invention, respectively, and FIG. 5 is an enlarged sectional view showing a fourth embodiment of the present invention. FIG. 6 is an explanatory front view showing a state in which a conventional X-ray image intensifier and television camera are combined. 2... Input window, 3... Output window, 4... Fluorescent screen, 10... X-ray image intensifier with solid-state image sensor, 11... Image intensifier body, 12... Optical fiber plate, 13...
phosphor (output phosphor screen), 14... solid-state image sensor,
15...Multi-channel plate, 16...
・Input fluorescent screen, 17... High voltage power supply, 18...
Electrode on hexagonal phosphor screen side, 19... Electrode on output phosphor screen side.

Claims (5)

[Claims] (1) The X-ray transmitted image that has passed through the subject enters the input window and is converted into a visible light image on the phosphor screen of the output window. A solid-state imaging device comprising an optical fiber plate that guides light in a straight line, and a solid-state imaging device that inputs the transmitted visible light image and converts it into an electrical signal on the exit side of the optical fiber plate. X-ray image intensifier with element. (2) The optical fiber plate is bonded to the inner surface of the output window of the image intensifier main body, and its entrance surface is coated with phosphor, and the solid-state image sensor is bonded directly to the outer surface of the output window. An X-ray image intensifier with a solid-state image sensor according to claim 1. (3) The output window portion of the image intensifier body is constituted by an optical fiber plate, the entrance surface of which is coated with a phosphor, and a solid-state image sensor is bonded to the exit surface of the optical fiber plate. X with solid-state image sensor
Line image intensifier. (4) The X-ray image intensifier with a solid-state imaging device according to claim 3, further comprising a multi-channel plate for multiplying light interposed between the exit surface of the optical fiber plate and the solid-state imaging device. (5) The solid state according to claim 1, 2, 3 or 4, wherein the electrode voltages of the input phosphor screen and the output phosphor screen of the image intensifier main body are shifted, and the electrode voltage on the output phosphor screen side is set to near zero potential. X-ray image intensifier with image sensor.