JPS607426A - X-ray photographing device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an Xa imaging apparatus, and particularly to an apparatus that performs indirect X-ray imaging while changing the irradiation areas of x, ;', and H.

The application and practical use of X-ray television equipment to medical diagnosis brought about ground-breaking progress and good progress in the conventional X#,'J diagnostic method, and was a result of the darkroom work of X-ray diagnosticians. Opening and X,
Due to the great advantage of reducing J.1 radiation exposure, a large number of devices are now being used in daily X-ray diagnostic work not only in Western countries but also in Japan, and the number of devices is expected to increase further in the future.

On the other hand, when performing fluoroscopic diagnosis or when taking images on XII film depending on the diagnostic condition, it is necessary to select a fake image that is easy to observe depending on the part, and to avoid exposing the subject to XII radiation to parts other than the necessary parts. It is common to use a movable aperture to adjust the X-ray irradiation field as appropriate.

That is, in Fig. 1, 1 is an X-ray generator, and 2 is a lead Xf-
It is a crest, and 6 is a shibori. When the diaphragm 2 is opened or closed from the R1 moderator 3, the irradiation angle of the X-rays changes, and the irradiation field (the area on the image conversion surface where the X-rays are incident) can be changed.

4 is a subject, for example, a human body. s tj: x, H
X formed on the input surface with an image intensifier
The line image is transformed into a fluorescent image, amplified by i degrees, and output. 6a
A projection lens has a function of converting output image light into parallel light, and 6b and 60 are imaging lenses for forming an image of the parallel light. 7 is an optical path switching mirror, and switching mirror 7? The light beam from the projection lens 6a is guided to the imaging lens 6b or 6C by moving the projection lens 6a to the imaging lens 6b or 6C.

8 is a video camera, 9 is a video receiver (monitor) LL
1o is a camera, 11 is a roll film, 12 is a controller, and 13 is an aperture diaphragm. Here, when X-rays are irradiated through the subject 4, the subject's X-rays are incident on the input surface of the image intensifier 50, and are formed as a visible image on the output surface. When the switching mirror 7 is set to the position indicated by the broken line, a transmitted image of the subject is refocused on the imaging surface of the video camera 8 and displayed on the video receiver 9.

When the examiner (doctor) confirms the image and releases the image, the switching mirror 7 is switched to the position shown by the solid line.) A transmitted image by the imaging lens 6C is formed on the roll film 11 and exposed. At that time, the examiner takes pictures while changing the aperture amount of the aperture 2 using the image stabilizer 3, but when the aperture amount is changed and the non-field is changed, the screen of the video imager 9 changes. Aperture on the left and right ends)
A shadow appears, and a transmitted image is projected in the irradiation field between them.

Therefore, if the feeding amount of the 10-film film is constant even though the range in which the image actually appears changes, that amount of film will be wasted if the image range is narrow. To deal with this, for example, when the first shooting is finished, the film is advanced by half the length of the first shooting field, and once the length of the second shooting field is determined, that length is Alternatively, information for half the length of the first shooting field is stored, information for half the length of the second shooting field is added, and the film is sent at once.

At this time, the aperture diaphragm 13 is controlled to 5 to correspond to the opening amount of the X iris diaphragm 2.

Next, the second step is to determine the shadow of the X-ray aperture from the video signal.
This will be explained using figures. Fig. 2 4t, t

The brightest part irradiated with X-rays shows a peak voltage Vp based on the L pedestal level, while the dark part where no X-rays are irradiated due to the XN aperture shows the pedestal voltage ■φ.

Here, in order to distinguish the shadow of the X-ray diaphragm, the maximum voltage vp of the XIN irradiation part is multiplied by a constant μ (0,2≦door≦0.3)
Using p as a threshold value, the area with a voltage lower than that voltage is identified as the shadow of the X bond diaphragm, and the 5 aperture diaphragm is closed to an aperture corresponding to that value, thereby limiting the shooting area.

However, with the above-mentioned conventional device, the only way to check whether the detected X-shape amount matches the X5-diaphragm amount actually viewed through the film is to examine the film, which takes time. There was a 5' defect.

It is an object of the present invention to provide an X-ray imaging apparatus that eliminates the drawbacks of the prior art and allows it to be easily confirmed whether or not any problem has occurred in the X-ray diaphragm detection system. - In order to achieve this object, the present invention is characterized in that the position of the detected X-ray print □ is displayed on the monitor along with the X-ray aperture.

Examples of implementation of the present invention will be described below. □FIG. 3 shows an embodiment of the present invention, in which the same symbols as in FIG. 1 indicate the same members.

Note that 14 is an image distributor for forming an image intensifier image on a film or a video camera, 15 is a camera controller for controlling the camera, and 16 is a video camera controller for controlling the video camera.

The image intensifier image captured by the video camera 8 is converted into a video signal by the video camera controller 16 and input to the camera controller 15.The camera controller 15 calculates the shadow of the X-ray diaphragm based on the above-mentioned principle. The size of the shadow is calculated on the camera 10, and the aperture diaphragm 13 is controlled.
A bright line 17 corresponding to the end of the aperture is displayed on the monitor 9 along with the video signal sent to the screen. The bright line 17 is displayed on the monitor as vertical m<broken line or solid line) by known signal processing.

Note that the manner in which the position of the X-ray aperture is displayed does not have to be in a straight line, and may be in a manner in which the position of the X-ray aperture is displayed.

Here, FIG. 4 shows an example of an electrical block diagram for implementing the present invention.

In the figure, Hd, Vd horizontal and vertical synchronous drive signals, A
s is the aperture opening data from the camera, FstJ: the camera video signal 21 is the synchronization separation circuit 22. After timing Δ 23 , the video comparator 24 detects the amount of X gland diaphragm based on the above-described principle, and the detection result is input to the first memory 25 . The stored value of the first memory 25 is the first
It is updated at predetermined time intervals using the memory update timing signal 25a.

The stored value in the first memory 25 is stored in the second memory 26 for aperture.
．． a second memory 27 for the film, and a matching circuit 28 . for the aperture, respectively. A film feed amount matching circuit 29 controls the aperture stop or film feed amount until it matches the amount counted according to the opening amount or the feed scene.

Aperture matching circuit 28. Matching circuit 2 for film transport
If the stored value and the count value match in step 9, each strike fC
No. 1 output is output as the camera 2 control signal 31 via the sequence control circuit '50.The second aperture memory 26. The stored value of the second film opening memo IJA is updated by the small second memory update timing signal 30a at a longer cycle than the first memory update timing signal 25a so as to match the projection.

Here, the X-ray pattern data 26R from the first memory 25 is input to the mixing circuit 62 together with the video signal, and the video signal 66 is outputted to the fluoroscopic monitor. Note that it is convenient to display the detected position of the aperture on the monitor, but instead to display the opening amount in numerical form, or to display a scale as a visual image so that the opening can be read directly.

As described above, according to the present invention, 't!' is displayed on the monitor. You can easily know the difference between the shadow of the aperture and the shadow of the aperture produced by controller 2, and easily confirm that there are no problems with the detection system.

[Brief explanation of drawings]

The frtJ1 diagram is an explanatory diagram of the conventional example, and Figure 2 CA) (II) is the X-ray aperture! +77) Shadow t Discrimination-3-7) tq< +qp, Figure-c, w13 Diagram of an embodiment of the present invention, Figure 4 is an electrical block diagram implementing the present invention, 1 in the figure indicates X-ray generation 2 is the X gland aperture, 3 is the aperture TFJ device, 4 is the subject, 5 is the X it! j image/tensifier, 8 is a video camera, '9-tj: monitor, 10 is a camera, 11 is a film, 12 is a controller, 16 is an aperture diaphragm, 15 is a camera controller, 16 is a video camera controller, 17 is a bright line. Applicant Canon Co., Ltd.

Claims (1)

[Claims] In a device that detects the opening amount of the LX gland diaphragm using a video signal and changes the amount of film advance and aperture diaphragm of a photographing device, the XH diaphragm at the position of the detected Xi An X-ray (k shadow) apparatus characterized in that both the comb image and the comb image are displayed on a monitor. Glandular imaging device.