JPS5858536A - Automatic x-ray exposure device - Google Patents

Abstract

PURPOSE:To set the image density of a concerned region to a proper value, by eliminating outputs of channels of X-ray exposure deficiency and exposure over with automatic switching in the fluoroscopy and selecting them with a manual operation in the photography. CONSTITUTION:A lighting visual field is selected automatically for fluoroscopy, and a specific lighting visual field is selected manually for photography. Respective output signals of lighting channels 11A-11N are compared with a reference signal in an over/under detecting circuit 19, and channel selecting and eliminating signals as the result pass through a latch circuit 23; and in fluoroscopy, only signals of channels selected by changeover switches 30A-30N are added in an adding circuit 13. In photography, the circuit connected to the latch circuit 23 is switched to a channel selecting switch 32, and changeover switches 20A-30N are controlled by a mode changeover switch 31 so that only signals of channels selected by the channel selecting switch 32 are inputted to the adding circuit 13.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an image intensifier (hereinafter [1,'
1. This invention relates to an improvement of an automatic X-ray exposure detection device for automatically controlling X-ray exposure by collecting a part of the output of a computer (referred to as J).

FIG. 1 is a diagram showing the configuration of the conventional X-ray automatic exposure control device. In the figure, 1 is the X-ray tube, 2 is the subject, and 3 is the X-ray tube.
line film, 4 is 1.1. ．． 5 is an optical system, 6 is a phototimer, 7 is a television camera, 8 is a television monitor, 9 is an X-ray photography condition setting circuit, and 10 is a high voltage generator;
．． A lighting device is installed within the field of view of the output of I and 4 to take in the light.
The phototimer 6 is operated based on these integral values, and the test object 2 is
The X-ray irradiation time corresponding to the X-ray tube 1 is automatically controlled via the X-ray imaging condition setting circuit 9 to control the X-ray irradiation time corresponding to the The quantity is optimized.・With such conventional X-ray automatic exposure control devices, control is performed based on the integrated light intensity from the entire lighting field of the lighting device, so if a part of the lighting field is, for example, insufficient in light intensity (hereinafter referred to as "under"), In the case of excess light intensity (hereinafter referred to as "over J"), in the former case, the xl generated from the X-ray tube 1 becomes stronger and the entire irradiation field becomes overexposed.In the latter case, however, the X-rays It had the disadvantage of becoming weaker and underexposed.

The present invention has been made in order to eliminate the above-mentioned drawbacks, and includes providing a lighting section consisting of a plurality of lighting devices (hereinafter referred to as channels) within the lighting field of the output of the image intensity and ear, and providing a lighting section for each channel. An X-ray device comprising: means for detecting that the output is X-ray underexposure and X-ray overexposure; and means for removing the output of the channel under the conditions of XS underexposure and X-ray overexposure using the output of the means.
ray exposure device, means for removing the output of the channel under the conditions of X-ray underexposure and X-ray overexposure only during fluoroscopy, and means for selecting the output signal of the channel in the region of interest by manual operation during imaging. The reason is that it is equipped with the following.

Hereinafter, the present invention will be explained in detail with reference to Examples.

In addition, in all the figures, the same parts are given the same symbols.

FIG. 2 is a schematic diagram showing the configuration of one embodiment of the basic part of the automatic X-ray exposure apparatus of the present invention. In the figure, 11
is a multi-lighting section that receives the output light of 1.1.4,
It is composed of a plurality of channels +1A to +11N. 1
Reference numeral 2 denotes an analog switch group, which is composed of a plurality of analog switches 12A to 12N-. 1'5 is the analog switch.

An adder circuit 14 adds the outputs from the channel group 12, and 14 divides the output from the adder circuit 16 by the number of channels.
Divide circuit for outputting average value per channel, 1
Reference numeral 5 denotes an output terminal, which is connected to the X-ray imaging condition setting circuit 9. 16 is a lighting field, that is, the channel 11A~
A terminal for inputting the selection signal C8 of 11N, 17 a circuit for generating a high and low signal R, 18 a detection reference signal generation circuit for detecting the over and under conditions, and 19 a terminal for each of the channels 11A to 11N. This is an over/under detection circuit that detects whether the output is over or under.

20 is a detection circuit for detecting that the outputs of all channels 11A to 11N are all over, 21 is a detection circuit for detecting that the outputs of all channels 11A to 11N are all under, and 22 is a detection circuit for all channels 11A
A detection circuit 23 is used to detect that one part of the signals .about.11N is over and the rest are under.The latch circuit 23 is put into a hold state by the latch signal R, and the output does not change during the hold state.

24 is a counting circuit for calculating the total number of operating channels, and 25A to 250 are analog switches.

When the level is high, it is off and low (L).
Turns on when level. 26 is a logical sum (OR) circuit, 2
7 is an over setting signal generation circuit, which generates a signal at a level such that, for example, the output of channel 11A is under (-). 28 is an under setting signal generating circuit, which generates a signal at a level when the output of channel 11A is under, for example. generates a signal.

29 is an rlJ signal generating circuit that generates a signal corresponding to "l" when representing the number of channels.

FIG. 3 is a diagram showing a specific configuration of the circuit of the multi-lighting section 11 shown in FIG. be.

FIG. 4 shows the over/under detection circuit 19 of FIG.
This is a diagram showing a specific configuration of an all-channel over detection circuit 20, an all-channel under detection circuit 21, and a partial under-detection circuit 22. In the figure,
Reference numeral 19A is a comparator for over detection, and the electrical signal Ei corresponding to the X-ray exposure from each channel 11A to 11N and the over condition reference signal E1 are input to each comparator, and when Ei)E, No. (1) It outputs a level signal. 19B is a comparator for under detection, and each comparator receives the electrical signal Ei and the under condition reference signal E! is input, and E i < E! When this happens, a signal of 1 (H) level is output. 119' (!1 to 19ON are logical sum (0) circuits for detecting whether each channel is over or under, 20A, 21A, 22A
are switching switches for daylighting field selection, and 1
When manipulating images, turn on all channels, take 2 split shots, and 4
When performing split operation, only the channel of the part of the output surface of I, 1.4 that is exposed to light is turned on. Channels that are not used should be set to high (■) level. 20B, 21B, 22B
are matching circuits, 30.51 is an inverter, E 0
1 is an all-channel over signal, Eat is a one-part over-remaining all-under under signal, E03 is an all-channel under signal, and E, , are signals for turning on the analog switch 25C.

FIG. 5 is a diagram showing a specific configuration of the child circuit 25 shown in FIG. In the figure, 25A and 26B are lighting field selection switches, and the a terminal side is set and g, and the b terminal side (high (■1) side) is reset. 230 is a switch for onset of all channels, and the H terminal has a low (L)
> level voltage is applied, and the L terminal is a normal over/under detection terminal. The outputs of the OR circuits 19C+ to 19ON shown in FIG. 4 are connected.

Next, the operation of the embodiment shown in FIG. 2 will be explained.

A, 25B to Zhuyu field of view ≠ cow signal US' ↓ a
Among the analog switches 12A to 12N of the analog switch group 12 connected to the terminal side, only the one corresponding to the lighting field is turned on. For example, in the case of single-frame operation, all of the analog switches 12A to 12N are turned on because the lighting field corresponds to all channels. Next, the subject 2 is irradiated with X-rays, and a visible image formed by an X-ray transmitted image is displayed on each channel 11A to 11N of the multi-lighting unit 11 provided within the lighting field of the output fluorescent surface in 1.1.4. Light corresponding to the amount of light inputted to each channel 11A to 11N is outputted, and an electrical signal Ei corresponding to the amount of light inputted to each channel 11A to 11N is outputted. Each output electric signal Bi of each channel 11A to 11N is
It is input to the over/under detection circuit 19 shown in the figure, and detects whether each electrical signal is over or under. Then, the OR circuit 19C corresponding to each channel 11A to 11N, respectively! The outputs of 1 to 19ON are input to the child circuit 23. For example, OR circuit 1 of channel 11A
If the output of channel 9C3 is at the i(H) level (that is, the output of channel 11A includes at least one of the over and under conditions), this is the input to the child circuit 26. Therefore, the output of channel 23A is at a high ()) level and the analog switch 12A is turned off (OFF). Since there is no output from channel 11A, there is no input to adder circuit 13. Also, the output of the OR circuit 190t of channel 11B is low (L).
If it is at the level, it is input to the secondary circuit 26, so the output of the latch 23A becomes low (L) level, and the analog switch 12B is in the ON state, so the analog output of channel 11B is directly input to the adder circuit 13. is input. Similarly, the outputs of other channels are also input to the adder circuit 13. In this way, the electrical signals Ei input to the adder circuit 13 are added and input to the divider circuit 14. On the other hand, the total number of channels 11A to 11N activated by the output of the latch circuit 23 is counted by a counting circuit 24 and input to the dividing circuit 14. The division circuit 14 divides the sum of the output electrical signals Ei by the total number of operating channels and outputs an average value for each channel. This output is the X-ray irradiation condition setting circuit 9
The optimal fluoroscopy and imaging conditions are set.

Next, when the logical sum circuits 19C3 to 19ON of the over/under detection circuit 19 output a detection signal indicating that one part is over and the remaining parts are all under, the coincidence circuit 22B of the one part over and remaining part under detection circuit 22 outputs one part. A signal GET indicating that the remaining part is over and the remaining part is under is output. This output signal E. l is input to the delay circuit 26, all of the channel onset switches 250 shown in FIG. 5 are switched from the L terminal to the H terminal, and the analog All analog switches corresponding to the lighting field of switches 12A to 12N are turned on. Then, the addition 2
An operation similar to that of division is performed.

Further, when all the outputs of the over detection comparators 19A of the over/under detection circuit 19 are over, an all channel over signal E is output from the coincidence circuit 20B of the all channel over detection circuit 20. 1 is output, and the analog switch 250 is turned on via the analog switch 25A and the OR circuit 26. As a result, a signal of "1" is inputted from the over setting signal generation circuit 27 and the "1" signal generation circuit 29 to the counting circuit 24 and the addition circuit 13, and a signal of "l" is output from the addition circuit 13, and the automatic exposure removed from control.

At this time, the overflow of all channels is determined by the OR circuits 1901 to 19 of the over/under detection circuit 19.
C! The signal is inputted to the child circuit 23 through N, and turns off all analog switches 12A to 12N. Also,
When all the outputs of the under detection comparators 19B of the over/under detection circuit 19 become under, the matching circuit 2j of the all channel under detection circuit 21
An all-channel under signal Eos is outputted from B, and the analog switch 250 is turned on via the analog switch 25B and the OR circuit 26, respectively. This results in
The “1” signal from the under setting signal generation circuit 28 and the “1” signal generation circuit 29 is sent to the counting circuit 24 and the addition circuit 13.
, a signal of "1" is output from the adder circuit 13-, and the automatic exposure control is removed.In this case, as in the case of all channels over, the output of all channels under depends on the over and above. OR circuit 190 of under detection circuit 19. ~19ON is input to the child circuit 26, turning off all analog switches 12A~12N.

However, in the embodiment of the basic part of the automatic X-ray exposure device of the present invention shown in FIG. 2, channels corresponding to preset halation conditions and under conditions are automatically Since the remaining channels are configured to compose the lighting field, light is automatically taken from any channel in the selected lighting field. As a result, there was a problem in that it was not possible to narrow down the field of view to a specific area of clinical interest. Recently, there has been a demand among people involved in X-ray diagnosis, such as doctors, to collect light only from a particular region of interest in order to optimize the photographic density of that region. On the other hand, fluoroscopy is often used mainly for positioning the part of the patient to be imaged, and it is sufficient to see the entire image rather than intentionally adjusting the density of a specific part, and the subject is not the same as the part to be imaged. Since the channel changes constantly due to movement, inflow of contrast agent, etc., it is desirable that the lighting channel be automatically selected according to the state of the subject, as in the past.

Therefore, the present invention eliminates the drawbacks of the basic parts,
In order to meet the above requirements, in the X-ray automatic exposure device with the multi-lighting field system shown in Figure 2, the lighting field is automatically selected during fluoroscopy, and when switching to imaging, it is possible to manually specify the region of interest, etc. It has a new function that allows you to select the lighting field.

FIG. 6 is a diagram showing the configuration of one embodiment of the analog switch group 12 of the embodiment of FIG.

Changeover switches 50A to 3ON are provided between the child circuits 23, and the changeover switches 30A to 3ON are controlled by a mode changeover switch 51. The mode selection switch 31 is set to the GND (ground) side when selecting the function of the embodiment shown in FIG. 2, and to the F/R (fluoroscopy/imaging switching signal input) when selecting the additional function of this embodiment. It is connected to the side. When connected to the F/R side, a fluoroscopic/imaging switching signal is input. In addition, push button switches A to N of the channel selection switch 62 are connected to one terminal of each of the changeover switches '30A-3ON, and the output of the latch circuit 23 is connected to the other terminal. The fluoroscopy/photography switching switch -y-/36 provided on the output side of the divider circuit 14 is used to switch and input the output of the divider circuit 14 to the fluoroscopy servo amplifier FSA during fluoroscopy and to the phototimer 6 during imaging. It is controlled by a fluoroscopy/imaging switching signal input to the mode switching switch 510F/R terminal.

Next, the operation of this embodiment will be explained.

Each output signal of the lighting channels 11A to 11N is compared with over and under reference signals in an over/under detection circuit 19. As a result, a signal is generated that distinguishes between the selected channel and the removed channel. This signal passes through the child circuit 23, and during fluoroscopy (F)
There is a switch switch.

Since the channels 30A to 3ON are connected to the child circuit 26 side, only the signal of the selected channel among the output signals of the channels 11A to 11N is added by the adding circuit 13. On the other hand, during radiography, the fluoroscopic/imaging switching signal is input to the gates of the changeover switches 30A to 5ON, and during fluoroscopy, the circuit that was connected to the sub-circuit 23 is switched to the channel selection switch.

switch to the 32 side. At this time, analog switch 1
The opening/closing of 2A to 12N is operated by the gate signal generated by the channel selection switch 32, so if the push button corresponding to the desired channel of the channel selection switch 32 is pressed, only the signal of that channel is input to the addition circuit 16. be done. The subsequent operations are the same as those in the embodiment shown in FIG. 2, and will therefore be omitted here.

FIG. 7 is a diagram showing the configuration of another embodiment of the present invention,
A memory 64 is interposed between the changeover switches 30A to 3ON in FIG. 6 and the channel selection switch 32, and when the channel combination of the lighting field to be selected is determined, the channel combination selection switch 3 of the combination pattern
By pressing 5, you can select the desired lighting field with one touch. In this embodiment, as in the embodiment shown in FIG. 6, a channel for the lighting field is selected using the channel selection switch and Chiro 2, but a part of the selected channel is stored in the memory 34, and it is desired to use that lighting field. In this case, if the address of the memory 34 is selected by the channel combination selection switch 5, the gate signals of the analog switches 12A to 12N corresponding to the lighting field will be output.

FIG. 8 is a diagram showing the configuration of another embodiment of the present invention.

In this embodiment, in the embodiments shown in FIGS. 6 and 7, the lighting channel during imaging is manually selected completely independent of the lighting channel during fluoroscopy, but this is selected as the lighting channel during fluoroscopy. It was made to be related.

In FIG. 8, 61A is a mode selection switch in which one terminal of a constant voltage source ■cc is added to the mode switching switch 1 shown in FIGS. 6 and 7, and this additional mode is as follows:
This is to enable automatic channel selection to be corrected by selecting or separating a part of the channel even during fluoroscopy. 36 is a switch that connects the output of the mode changeover switch 31A to GND (ground) during fluoroscopy and to the constant voltage source Vcc during photography, and 67 is a changeover switch 30A to 30A during photography.
This is a gate switch selection switch that selects the switch to be gated among the 3ONs, and the changeover switches 308 to 3O
It consists of switches A-N corresponding to N.

To explain the operation of this embodiment, mode selection switch 3
When 1A is connected to the F/R side, a fluoroscopic/imaging switching signal is input. In this case, at the time of photographing, the transparent lighting channel is automatically switched as in the embodiments of FIGS. 6 and 7.

When the signal changes from fluoroscopy to photography, switch 36
is connected to the constant voltage source Vc'c on the R side. If you close the switch of a certain channel or channel of the gate switch selector switch 37, when switching to shooting, a gate signal will be sent to the switch of the selected channel among the selector switches 30A to 3ON. , the connection is switched from the child circuit 23 side to the channel selection switch 32 side.

That is, the channel selection switch 320) is released from the mechanism that holds the selected channel, and the opening and closing of the analog switches 12A to 12N are controlled by operating the channel selection switch 320).

Furthermore, if the mode selector switch 31A is set to the GND side, the operation will be the same as that of the embodiment shown in Fig. 2, and if it is set to the constant voltage source Vce side, a part of the channel will be selected even during fluoroscopy. You can now modify automatic channel selection by adding or detaching channels.

In addition, in each of the above embodiments, the output of channels with X-ray underexposure and X-ray overexposure is removed, the outputs of the remaining appropriate channels are added, and the value is divided by the number of daylighting channels to calculate the output per channel. Although the description has been made using a multi-lighting field type automatic X-ray exposure device in which the X-ray exposure conditions are set using the average value of Needless to say, you can get it.

As explained above, according to the present invention, in a multi-lighting field type automatic X-ray exposure device, outputs of channels with X-ray underexposure and X-ray overexposure are removed, outputs of remaining appropriate channels are added, By dividing that value by the number of employed channels and setting the X-ray exposure conditions using the average value per channel, we can set the X-ray fluoroscopy and imaging conditions that correspond to the optimal X-ray exposure conditions. can do. In addition, since the lighting field is automatically selected during fluoroscopy and manually selected during imaging, changes in the brightness of the television and monitor due to changes in the subject are suppressed during fluoroscopy, and the monitor image that determines the location of the area to be imaged is is easy to see, and the density of areas of clinical interest can be adjusted to the appropriate density during imaging without relying on experience.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of a conventional X-ray automatic exposure control device, FIG. 2 is a professional diagram showing the configuration of an embodiment of the basic part of the present invention, and FIG. , a diagram showing the specific configuration of the circuit of the multi-lighting section in Figure 2, and Figure 4 shows the over/under detection circuit, all-channel over detection circuit, all-channel under detection circuit, and one over-remaining circuit in Figure 2. 5 is a diagram showing a specific configuration of the latch circuit of FIG. 2,
FIGS. 6 to 8 are diagrams showing the configuration of an embodiment of the lighting field switching section of the present invention. 6 Phototimer 12...Analog switch group 1...Addition circuit 14...Division circuit 19 Over/under detection circuit 23...U, CH circuit 24.Counting circuit 50A~5ON
Changeover switch 31.31A'-, mode changeover switch 32 Channel selection switch 33-fluoroscopy/photography changeover switch 34 Memory 35 Channel combination selection switch, Chiro 6 Switch 37... Gate switch, Chi selection switch Agent Patent attorney Aki 1) Shu Ki Akira 3 figure H1 day

Claims (1)

[Claims] A means for providing a lighting section consisting of a plurality of lighting devices within the lighting field of the output of the image intensifier, and detecting whether the output of each lighting device is under-exposure or over-exposure of X-rays; and the means. An automatic X-ray exposure device comprising means for removing the output of the daylight under the condition of underexposure of X-rays and overexposure of X-rays by the output of An automatic X-ray exposure device characterized by comprising means for removing the output of the device only during fluoroscopy, and means for selecting the output signal of the daylight in the region of interest by manual operation during imaging.