JPS6223856B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an X-ray imaging device, and in particular to a fluorescent image intensifier (hereinafter referred to as II).
The present invention relates to a device equipped with an X-ray camera that records a fluorescent image of a subject displayed on a tube) on a long film. Recently, as medical standards for X-ray staining have become stricter,
A transmitted fluorescent image formed by a small amount of X-rays is multiplied by an II tube, the image is observed on a television receiver, and when the image displayed on the receiver is the desired one, a long roll of X-ray camera is used. - Devices that take pictures on film are widely used.

At that time, the size of the photographing field in which the photograph appears on the film changes each time a photograph is taken, but if the feed rate of the roll film is always constant, if the size of the photographing field is small, the previous photograph and the current photograph will be different. There are blank spaces in between, and there is a lot of waste. Utility Model Application No. 52-106138 is known as a solution to this drawback, but the method is to feed half the size of the previous and current shooting fields at once when the film is fed this time. There is.

On the other hand, in addition to setting the film advance amount, the shooting operations include setting the aperture of the aperture that changes the X-ray irradiation field placed in front of the X-ray generator, and adjusting the size of the image frame provided just before the film. Since the adjustment of the width was performed, there was confusion as the setting of the feed amount and the adjustment of the aperture amount were inconsistent. In addition, in Utility Model Application No. 52-106138, since the number of pulses is counted when moving the film, there is a limit to the film moving speed due to its responsiveness, and the film cannot be moved at high speed. An object of the present invention is to appropriately match the adjustment of the aperture that changes the X-ray irradiation field with the amount of film feed.

Examples will be described below with reference to the drawings.
The figure is a conceptual diagram of the whole, FIG. 4 is a diagram showing the mechanical system of the X-ray camera, and FIG. 7 is a diagram for explaining the electrical system.

In FIG. 1, 1 is an X-ray generator, and 2 is an aperture for changing the irradiation field. Reference numeral 3 denotes a driver for driving the aperture 2, through which the aperture amount is set manually or by remote control. 4 is the subject. 5 is II tube, 5a is input surface, 5b
is the output surface. 6 is a collimator lens,
It has a function of converting the luminous flux from the fluorescent image displayed on the output surface 5b into parallel light. Reference numeral 7 denotes an image distribution mirror, and the optical path can be switched by moving the position indicated by the solid line and the position indicated by the broken line. 8 is a telemeter/imaging lens. 9 is a television camera, and 9a is an image receiving surface of an image pickup tube. The imaging lens 8 forms an image of the light beam from the collimator lens 6 onto an image receiving surface 9a. 10 is a television receiver. Reference numeral 11 denotes an imaging lens of an X-ray camera 12, and the lens 11 forms an image on a roll film 17 of a light beam that passes through the lens 6 and is reflected by a mirror 7. Reference numeral 13 denotes a signal detector that detects the size of the current imaging field from the size of the irradiation field determined by the aperture 2 from the video signal coming from the television camera 9, and sends a signal corresponding to the size to the camera 12 via a conductor 14. It has the function of sending the film to the film feeder. In other words, assuming that an X-ray perspective image is projected on the television receiver in Fig. 2, 2' and 2'' are the shielded areas created as a result of narrowing down the aperture 2, and no subject information is contained in these areas. Since it is not included, there is no point in photographing the entire screen.Therefore, by scanning the screen and detecting the distance L between the occluded areas, the dimensions of the photographed field can be determined from the proportional relationship between the screen and the film. , it is possible to form a signal according to the size.

When the X-ray generator 1 is driven with the above configuration, I.
An X-ray transmission image of the subject 4 is formed on the input surface 5a of the I. tube 5, and an X-ray transmission image with amplified brightness is formed on the output surface 5b due to the action of the II tube. At the time of observation, the mirror 7 is moved to the position indicated by the broken line, and the image on the output surface 5b is formed on the image receiving surface 9a of the television camera 9 by the action of the lenses 6 and 7, and the image is displayed on the image receiver 10. On the other hand, if we assume that the photo S shown in Figure 3 has been imprinted on the roll film due to the previous shooting, the roll film will be S/2 by the end of shooting.
or a signal corresponding to S/2 is stored in a storage circuit (not shown).

The examiner who is observing the screen of the image receptor 10 can see the imaged area and the area 2' blocked by the aperture.
When the shutter release operation is performed after recognizing that 2" is appropriate, the detector 13 detects the width L of the exposure field using the method described later, and determines the current field size (actually half of that,
A signal corresponding to t/2) in FIG. teS/2+t/
Wind the long film by 2, make the photographing field of the long film adjacent to the previous photographing field, and then use lenses 6 and 11.
Due to this action, the image of the output surface 5b is formed on the film 17 and photographed.

Next, FIG. 4 depicts the mechanism of the X-ray camera to explain the two-time feeding of the long roll film and the setting of the image frame. The film 17 is transferred from the supply side spool 18 to the storage side spool 18' by ratchet wheels 19,1.
9' and presser rollers 20, 20'. The holding rollers 20, 20' have the function of pressing the film 17 against the claw wheels 19, 19' by means of a spring force and applying frictional force when the film is fed. (The spring is not shown) When a signal indicating the size of the irradiation field is received using the method described above, the shutter membranes 36 and 37 operate to the corresponding image frame size, and at the same time feed an amount of film corresponding to the image frame. will be held. When the motor 21 is energized, a gear 22 fixed to its output shaft rotates, and power is transmitted to a gear 23 meshing with it. The ratchet 19' and gear 23 are attached to a shaft 24, and when the gear 23 rotates, the ratchet 19' also rotates in the direction of arrow a, and the film 17 is fed in the direction of arrow b and taken up on the storage spool 18'. It will be done. The storage spool 18' rotates in the direction of arrow c via the shaft 24 and friction means (the friction means are not shown). When the film 17 is fed, the ratchet wheel 19 is rotated. A ratchet wheel 19 and a chopper 26 are attached to the shaft 25, and when the ratchet wheel 19 rotates, the chopper 26 also rotates in the direction of arrow d. A large number of slits 27 are arranged in the chopper 26 in the circumferential direction, and the number of slits is counted by a known photo sensor 28. For example, a photo sensor is provided with a light emitting diode on the upper side and a light receiving element on the lower side facing each other. After counting the number of slits corresponding to the amount of film fed, the power to the motor 21 is cut off to stop the film feeding. If there are perforations on the long film, you can count the number with a photo sensor, or you can accurately measure the number of revolutions of the ratchet wheel because the feed claw precisely engages each perforation. If you decide, you won't need a sensor.

Next, the operation of the image frame will be explained. A sprocket 29 attached to the shaft 24 and a sprocket 3 attached to the input shaft of a known electromagnetic clutch 32.
0 are connected by chain 31. Therefore, when the motor 21 is rotating, the sprocket 30 is also rotating. Furthermore, the chain 31 can of course be replaced with other transmission parts such as a timing belt. motor 2
At the same time as power is applied to the electromagnetic clutch 32, the gear 33 attached to its output shaft rotates. When the gear 34 meshing with the gear 33 rotates, the shutter winding shaft 35 also rotates (the gear 34 is fixed to the shutter winding shaft 35), and the shutter film 36 attached to its outer periphery moves in the direction of arrow e. Move to. Shutter ribbons 37 are attached above and below the tip of the shutter membrane 36, and the ends of the shutter ribbons 37 are attached to the outer periphery of a rotatable drum 38. Further, a shutter film 36' is wound and attached to the drum 38 in a direction opposite to that of the shutter ribbon 37. A shutter ribbon 37' is attached above and below the tip of the shutter membrane 36', and its end is attached to a spring drum 39. The pulleys 40, 41, 42 are rotatable. One end of the coil spring 44 is fixed to the spring drum shaft 43, and the other end is fixed to the spring drum 39. When the gear 43 attached to the shutter hoist shaft 35 rotates, the gear 44 meshing therewith rotates, and the ratchet wheel 45 also rotates. When the shutter film 36 moves in the direction of arrow e, the shutter film 36' moves in the direction of arrow f. Shutter membrane 36, 3 opened to the left and right
The size of the image frame 46 is determined by the amount of movement of the frame 6'. The movement of the shutter ribbon 37' rotates the spring drum 39 and twists the coil spring 44. The ratchet pawl 47 is always in contact with the teeth on the outer periphery of the ratchet wheel 45 due to the spring 48.

Shutter film 36 to the specified picture frame size,
36' is activated, the electromagnetic clutch 32 is immediately de-energized. The shutter membranes 36, 36' are mechanically held by the aforementioned ratchet mechanism. Also,
Of course, this holding function can also be achieved by electrical holding such as an electromagnetic brake. Shutter membrane 36, 36'
Detection of the amount of operation is performed by a chopper 26' attached to the shutter hoisting shaft 35.
A large number of slits 27' are arranged in the circumferential direction of the chopper 26', and the number of the slits is counted by a photo sensor 28'. After counting the number of slits corresponding to the size of the picture frame, the electromagnetic clutch 32 is de-energized and the picture frame is set. This is the end of the first stage of operation, and the camera is ready to take pictures at any time.

Next, we will explain the operation of the second stage. When the photographing is completed and a photographing end signal is received, the motor is energized and feeds an amount of film equivalent to half the size of the photographed image frame. The feed amount is photo sensor 2
8 is as described above. During this time, the solenoid 49 is energized and the ratchet pawl 47
is separated from the ratchet wheel 45 and the shutter membrane 36,
36' moves in the direction opposite to the arrows e and f due to the restoring force stored in the coil spring 44 and returns to its original position. Its position is determined by a pin 50 and a stopper 51 fixed to the ratchet wheel 45. It goes without saying that the electromagnetic clutch 32 is released during the return operation of the shutter membranes 36, 36'. Next, during this second stage of operation, it is possible to set the irradiation field for the next imaging.
Once the size of the irradiation field is determined, a film amount equivalent to half of the image frame of the X-ray camera corresponding to the size is fed and the image frame is operated. The camera is now ready for the next shot.

The above is one cycle of operation of the variable film advance mechanism and variable image frame mechanism of the X-ray camera. By repeating this operation and taking pictures one after another, the pictures are taken on the film, and there is no overlap between adjacent pictures, making effective use of the film. Furthermore, when consecutively photographing a plurality of frames with the same irradiation field size, this becomes possible by selecting a control circuit for continuous photographing, which will be described later. In this case, immediately after photographing is completed, the amount of film corresponding to the image frame is fed at one time. By doing this, you will be able to take the next shot immediately after film feeding is completed.
This is an effective method mainly for continuously photographing dynamic subjects.

On the other hand, when the output image of the II tube is taken with a camera, it is convenient to record data related to the photograph, such as the patient number and the elapsed time since the start of the photograph, for later document organization. .

The system consisting of members 52 to 58 in FIG. 4 is a data imprinting system, and 52 is a data display in which, for example, seven segment light emitting diode chips are arranged, and it is assumed that it faces toward the back side of the film 17. . A projection lens 53 has the function of forming an image of the data displayed on the display 52 onto a film. A gear 54 meshes with the picture frame determining gear 34, and also meshes with a drive gear 54'. This drive gear is connected via a shaft to another gear 54'', which meshes with a pinion 55. Reference numeral 55' denotes a rack, which meshes with the pinion 55. As a result, when the pinion 55 rotates, the rack 55' is guided by a guide (not shown) and moves parallel to the film surface. Further, the display device 52 and the projection lens 53 are supported by a rack 55' and move with the movement of the rack 55'.

With the above configuration, the rack 57 moves via the gears 54 to 55' at the same time as the shutter winding gear 34 rotates to determine the image frame, and the radar is moved near the side of the photographing field in the second stage. A display 52 and a projection lens 53 are set at appropriate positions for imprinting, and the display 52 emits light in synchronization with photographing to imprint data. D ₁ in Figure 5,
D ₂ and D ₃ show the imprinted data.
It is assumed that the display device 52 and the projection lens 53 are housed in a light-shielding tube to prevent light from entering unnecessary portions of the film. Also, here the display and projection lens are moved in parallel,
The optical axis may be rotated around the position of the display, or a mirror may be placed in the optical path after the projection lens and the position of the data may be moved by shaking this mirror.

FIG. 6 shows an example in which the aperture amount of the aperture 2 is detected, this detected amount is converted to the size of the imaging field at the time of current imaging, and a signal corresponding to the size is output to the X-ray camera 12. In the figure, numeral 56 denotes a detector that detects the amount of aperture and outputs a feed amount command signal, and can be constructed by using, for example, a potentiometer and connecting it to the rotating shaft of a handle that opens and closes the aperture 2.

Next, in the electrical system block diagram shown in Fig. 7,
Reference numeral 57 denotes a video amplifier that amplifies the composite video signal Vs including horizontal and vertical synchronizing signals outputted from the television camera 9 in FIG. 1, or the video signal V not including the synchronizing signal. Reference numeral 58 denotes a comparator having an aperture voltage detection level adjuster that can adjust the detection voltage level of the aperture position amount voltage of the II tube included in the video signal Vs or V. 59 is a pulse oscillator whose oscillation frequency can be varied. 60 is comparator 5
During the period (time) when the II tube is not apertured for each scanning line output from 8, a signal whose voltage is at a high level is used, and during that high level period, the pulse oscillator 5
AND circuit to convert time to number of pulses by gating how many pulses from 9 are emitted. 63 is a synchronization signal separation circuit that separates a composite synchronization signal Sync containing both horizontal and vertical synchronization signals when the composite video signal Vs is input to the video amplifier 57; 64 is a frequency filter unit that discriminates the horizontal synchronization signal Hsync and the vertical synchronization signal Vsync from the composite synchronization signal Sync. 65 is the frequency filter section 6
While counting Hsync and Vsync obtained from 4,
A sampling control circuit that controls which scanning line of the video signal in one field is used to detect the aperture position of the II tube. Reference numeral 61 denotes a timing signal for starting and canceling counting of the pulse number which is commanded by the sampling control circuit 65 for the number of pulses for each scanning line outputted from the AND circuit 60, and a pulse number counting prohibition command which is commanded by the camera operation control circuit. , a circuit that counts and stores the number of pulses according to command signals to start storing the number of pulses and to erase stored contents. Reference numeral 67 denotes a shutter film movement amount detecting section for detecting the movement amount of the shutter film, and includes a photo sensor 28'. Reference numeral 68 denotes a film movement amount detection section which has a function of detecting the amount of movement of the film and includes a photo sensor 28. 62 is a camera operation control circuit;
It receives pulses from the circuit 61 that counts and stores the number of pulses, and also pulses the film winding command based on the X-ray generation signals P and B input from the X-ray generator 1 and the switching signal CHNG for the mirror 8 of the image distributor. A function to send a stop signal to the motor 21 by counting the number of pulses obtained from the film movement amount detection section 68 to a predetermined number of pulses, or to control the shutter film using a similar procedure. have. Next, SW ₁ is a synchronization signal changeover switch, which is switched when inputting a signal V that does not include a synchronization signal instead of the video signal Vs, and is used to obtain a horizontal synchronization signal Hsync and a vertical synchronization signal Vsync from the decoded synchronization signal. It is something. SW2 is an aperture amount detection signal changeover switch for switching between the signal of the detector having the configuration shown in FIG. 1 and the signal of the detector having the configuration shown in FIG. SW3 is a changeover switch that allows you to switch between single-frame shooting, in which the camera searches for the film field (irradiation field) each time it is shot, and continuous shooting, in which multiple frames are shot in succession in the same irradiation field. Note that the number of frames for continuous shooting can be arbitrarily set using a frame number command signal NST.

In the above configuration, when the aperture amount detection signal changeover switch SW2 is on the irradiation field detection side based on the video signal and the continuous/single-shot shooting changeover switch SW3 is on the single-shot side, the observation television camera 9 detects the radiation from the X-ray transmitted image. As long as a video signal is generated, the aperture position (distance between the two shielding areas) is always output from the AND circuit 60.
The counting/memory circuit 61 generates a pulse corresponding to
counts the number of pulses for each field according to the timing from the sampling control circuit 65,
Remember. At the moment when the X-ray generator 1 is driven and the mirror 7 of the image distributor switches from the X-ray television to the X-ray camera, the camera operation command control circuit 62 detects the rising edge of the switching signal and immediately starts the counting/memory circuit. Read the number of pulses in the field before 61, advance the film by half the number of pulses in a short time until the image distributor finishes switching to the X-ray camera side, and at the same time operate the clutch 32 to open the shutter membrane. Set the image frame. After that, X-rays are generated, and when the imaging is completed, the film is wound for half the number of pulses still stored in the camera operation command control circuit, and at the same time, the shutter film is released by the shutter film release unit, and the shutter film is released for the next command. It's ready.

If the number of frames NST is set after switching switch SW3 to the continuous shooting side, the film winding command will be switched to the number of pulses stored after X-ray generation until the number of shots set in NST is completed. Change. Furthermore, when the changeover switch SW2 is switched, the operation can be performed in the same manner as described above, except that video signal processing is not required.

As explained above, according to the present invention, when the X-ray irradiation field is changed as necessary during observation, it is automatically linked to film advance, so even if the irradiation field changes one by one, This eliminates the problem of inconveniences such as incorrectly specifying the film feed amount, resulting in a photo that is narrower than the irradiation field, or overlapping photos, which ruins not only that photo but also the photos before and after it. This has the effect of eliminating the troublesome effort of inputting the information one by one.

Further, in the present invention, since the film is moved by the output of the video signal detector, it is possible to move the film at a higher speed than in a method in which the number of pulses is counted when moving the film.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view showing an embodiment. Figure 2 is a front view of the receiver. Figure 3 is a plan view of the film. Fourth
The figure is a perspective view of the film feeding mechanism. FIG. 5 is a plan view of the film. FIG. 6 is a schematic cross-sectional view of another detection example.
Figure 7 is an electrical block diagram. In the figure, 1 is the X-ray generator, 2 is the aperture, and 5 is II
7 is an image distribution mirror, 9 is a television camera, 10 is a television receiver, 12 is an X-ray camera, 13 is a video signal detector, 17 is a long film, 18 and 18' are spools, 19 and 19' are Ratchet wheel, 20 and 20' are presser rollers, 21 is a motor, 26 and 26' are choppers, 28 and 28' are photo sensors, 32
is an electromagnetic clutch, 49 is a solenoid, 57 is a video amplifier, 58 is a comparator, 59 is an oscillator, 60 is an AND circuit, 61 is a counting/memory circuit, 62 is an operation command control circuit, 63 is a synchronous separation circuit, and 64 is a frequency Filter section, 65 is a sampling control circuit, 6
6 is a shutter film release unit, 67 is a shutter film movement amount detection unit, 68 is a film movement amount detection unit, 69
is the range of the X-ray camera.

Claims (1)

[Scope of Claims] 1. A fluorescent image intensifier tube comprising an aperture that changes an X-ray irradiation field and an output surface that is optically conjugate with the aperture;
An image distributor is installed, and the image distributor distributes the image displayed on the output surface of the fluorescent image intensifier to a television camera coupled to an image receiver and an X-ray camera that sends a long film. A radiography apparatus includes a video signal detector that detects the field size from the video signal received by the television camera, and a video signal detector that detects the field size from the video signal received by the television camera. An X-ray imaging apparatus comprising a moving means for moving a long film by half of the current imaging field size from a state where the imaging field position is moved in the film movement direction from the imaging optical axis. 2. X-ray imaging according to claim 1, in which the state in which the previous imaging field position is moved from the imaging optical axis in the film movement direction by half of the previous imaging field size is formed by the completion of the previous imaging. Device. 3 The state in which the previous imaging field position was moved from the imaging optical axis in the film movement direction by half the previous imaging field size is formed as the first half of the operation of moving the long film by half the current imaging field dimension. An X-ray imaging apparatus according to claim 1.