JPS6271198A - X-ray photographing device - Google Patents

Abstract

PURPOSE:To perform X-ray automatic exposure most suitable for kinds of sensitized paper and X-ray films, by installing both a device for detecting kinds of the sensitized paper and the X-ray films, and a device for memorizing concentration characteristics to specific exposed amount. CONSTITUTION:Kinds of films and sensitized paper stored in a cassette 5 are expressed with bar code marks 6. And the marks 6 are read by a bar code reader 7, and their signals are inputted to a mu-CPU 12 through a film sensitized paper output signal circuit 9 and a film/sensitized paper input signal circuit 10. The CPU 12 has access to a memory 13 in order to search for data of the relevant films and sensitized paper in accord with stored data, and besides to hold tube voltage property of sensitivity to the relevant film and sensitized paper through a tube voltage-set circuit 18 and the memory 13. X-ray automatic exposure suitable for the kinds of sensitized paper and films can be performed with these data.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an X-ray apparatus equipped with an automatic exposure control circuit;
In particular, by automatically reading the type of film and intensifying screen, the optimal self-eH according to the type of film and intensifying screen can be set.
The present invention relates to an Xa imaging device that enables Xa emission control.

[Artistic view of the invention] In order to optimize the degree of blackening of the transmitted image of the subject photographed on the X-ray film, an automatic exposure control circuit (hereinafter referred to as AEC) has conventionally been used.
) 0-sure Control ) circuit)
has been used. This circuit detects XI! when the integral value of Xa detected by the X-ray detector placed in the X-ray pulse passing through the subject exceeds a preset value (exposure value). Cut off the high voltage application to the source and stop Xa exposure. It is 8H sulfur. As a result, the optimal exposure amount can be obtained by automatically controlling the aADA time for any subject of any body thickness or for any part of the image.

Generally, such conventional Δ[C circuits were always controlled by one system of sensitivity.

In addition, in recent years, it has been equipped with a switching circuit that allows sensitivity to be selected according to various shooting conditions, and a switching circuit is provided on the operation panel.
ΔEC circuits that allow an operator to switch as appropriate using two or three changeover switches are also becoming increasingly popular.

[Problems with the background art] As the technology in X-ray W-sho improves year by year, many types of films and increased F! I started using 4ta union U. In addition, there has been a rise in the number of photographic stations that can be used for all W Shou α or close to the same, from those that are exclusively used for certain parts of the body.

Under such circumstances, the ability of the AEC circuit to have only one sensitivity is extremely inconvenient for the operator. In addition, even if the camera has a sensitivity switch, the operation is performed manually using a switch on the control panel, so the operator must always pay attention to the film and intensifying screen built into the cassette when shooting. If you make a mistake in switching, the photo will have to be taken again, resulting in unnecessary X-ray irradiation. Furthermore, when a new type of film or intensifying screen is introduced, it is necessary to investigate the light intensity and density characteristics of the combination and readjust the ΔEC circuit.

Furthermore, the number of selector switches on the operation panel is naturally limited, so if more films and intensifying screens are required, they must be assembled together, which reduces the film density. This was a cause of variation.

Of course, depending on the number of combinations of film intensifying screens, it would be theoretically possible to place selector switches all over the operation panel, but the operator would be burdened with the hassle of selecting a switch from among a large number of switches. What is AEC for?
It is conceivable that this may lead to doubts about whether this is the case.

[Objective of the Invention J The present invention has been made in view of the above circumstances, and its purpose is to
The purpose of the present invention is to provide an X-ray apparatus that enables EC.

[Summary of the Invention] The apparatus according to the present invention includes HI photosensitive paper and X41! The present invention is characterized in that it detects type 1 data of the film and performs optimum AEC based on this detected data.

[J? EMBODIMENT 1 OF THE INVENTION Hereinafter, the configuration of an embodiment of the present invention will be described with reference to FIGS. 1 to 4.

FIG. 1 is a schematic block diagram of an implementation of W4vt.

In the figure, the X-rays emitted from X-ray tube 1 are aimed at subject 2 and AE.
After passing through the C detection circuit 4, an intensifying screen built into the cassette 5 emits light, and the X-ray film is exposed to the light. A bar code mark 6 is pasted on the cassette 5 to code the type of film and intensifying screen contained therein. The cassette holder 8 that holds the cassette 5 is equipped with a barcode reader 7 that reads the barcode mark. and is transmitted to the film/mass @Gishin Yumi output circuit 9.

In addition, the above-mentioned A
EC detection circuit 4. Carette holder for attaching Power Lotte 5 and barcode reader 7 8. A film/intensifying screen signal output circuit 9 is provided. The signal output from the film/intensifying screen signal output circuit 9 is sent to the XIQ control device 1.
9 is transmitted to the film/intensifying screen signal input circuit 10,
The information 1q is sent to μ through data bus DB1.
The information is transmitted to the mCPU 12.

The data on the type of film and intensifying screen is μmCl) U12
When transmitted to data bus DB2, μmCPLJ12
The system accesses the +m'I device 13 via , searches for the data corresponding to the corresponding film/sensitized film from among the pre-stored stationary light and density characteristic data, and uses this data as the basis. The sensitivity of the detection circuit of the AEC circuit and the integral constant of the integrating circuit, which will be described later, are calculated and this data is held.

Furthermore, the μm CPU 12 takes in the currently set imaging tube voltage data from the tube voltage setting circuit 18 via the data bus DBS, accesses the storage device 13 again via the data bus DB2, and sets the data for the film and intensifying screen. Search the sensitivity tube voltage characteristic data, find a compensation value for the reference tube voltage, and hold it.

When the above data search and performance are completed, μmCPU1
2 sequentially transfers sensitivity selection data of the detection circuit of the AEC circuit, integration constant selection data of the integration circuit, and tube voltage compensation data to the data latch circuit 14 via the data bus DB4.

Of the data transferred to the data latch circuit 14, the detection circuit! :j The 4 degree selection data is transmitted to the detection circuit 4 via the sensitivity selection signal 5/1 output circuit 15 via the data bus DBS. In the figure, a indicates this detection circuit sensitivity selection signal. or,
Integral constant selection data and tube voltage compensation data are sent to the automatic exposure compensation circuit 16 via data buses DB6 and DB7 as integral constant selection ig @ (C in the figure) and tube voltage wJ compensation signal d> in the figure, respectively. communicated.

An embodiment of the detection circuit is not shown in FIG. 4A in the figure is △+=
This is a C detector, which outputs a current proportional to the amount of X-rays that have passed through the subject. The output current is the operational amplifier OP
1,! J L/-AI'1ly4-1~Ry4-n
and low resistance converter 1 (converted to electric power by current voltage converter 4B consisting of 71-1 to R4-n, output buffer -4C
The detection signal is then transmitted to the X-ray automatic exposure circuit 16 as a detection signal.

Further, the aforementioned detection circuit sensitivity selection signal a is transmitted to the decoder 40, and the relay group R is selected according to the type of film/intensifying screen.
The other one of yl-1.~l-<y4-11 is driven.

FIG. 3 shows an embodiment of the self-fJJ exposure correction circuit.

Previous) The book detection signal 6G is output from the operational amplifier OP2 in the automatic exposure compensation circuit 16. Relay group RV2O-1~Ry16-n
.

10 is integrated into an integrating circuit 16Δ consisting of 3 groups of resistors R16-1 to R1G-n and a condenser 1G,
This will be communicated to 6C. Is 16B the reason? When the X radiation is completed, the charge of C1G is discharged and the integration circuit 16Δ is reheated.

On the other hand, the tube voltage compensation data signal d outputted from the μm CPU 12 is converted into an analog signal by the D/A converter 16 [), and is applied to the fJ adder 16F.

The adder 16 adds the reference signal r obtained by adding the tube voltage compensation signal to the signal output from the reference signal generation circuit 16E to the comparator 1.
Output to 6C. The comparator 16C uses the reference (i'; 3if
and the integral signal 9, and when the integral signal reaches the level of the reference signal 9, an X-ray exposure end signal e is output to the timer circuit 17 via the driver 1611.

Further, the above-mentioned integral constant selection signal C is transmitted to the decoder 16G, and the relay 8￥R is transmitted depending on the type of film or intensifying screen.
One of V2O-1 to Ry1B-n is driven.

The timer circuit 17 which inputs the above-mentioned X-ray exposure end signal '; As a result, the output of the high voltage generating circuit HV G is cut off, and the X-ray source 1 stops imaging.

Next, the sensitivity 1 of the film/intensifying screen, the resistors i R4-1 to R4-0 in the detection circuit 4 which performs switching corresponding to this, and the resistors R1G-1 to R16 in the automatic exposure compensation circuit 16. −
The relationship between n will be described.

For example, Jg is calculated for films/intensifying screens with different sensitivities 1 and 1=2 shown in Figure 54. D) is taken.

Now the standard 'fAIf! , is 1.0, and the exposure depth required to obtain the reference density for [1 and F2 is El, F2, then from the figure, X2 = Xi + X Therefore, log (IE2 /' EO) = log < [ El /EO) + 1 of 1oQA
1'I relationship is established. Here, [0 is the semi-exposure limit, and △X
=IO! l△ has a constant C.

That is, [2...△ becomes 1.

In addition, the resistors in the detection circuit 4 and the resistors in the integrating circuit 1θΔ for “1” and “2” are R4-1 and R4-1, respectively.
2, RIG-1 and R16-2, the following relational expression (hereinafter referred to as j' white) holds true. Here, 11.12 is the @pulling time required to obtain the reference concentration at Fl, F2, 11゜i2
These are the output currents of the detector 4A in each case.

By the way, the integral value of the ray l output from the X-ray tube, the exposure light amount, and the output current from the detector 4△ holds true, and (1
) formula is R4-1x R16-2/ R4-2x R16-1=
becomes Δ.

However, the relative sensitivity ratio can be determined from the stationary light distance and density characteristics of each combination of film and intensifying screen, and a constant resistance that satisfies the above equation can be selected. Of course, in combinations of films and intensifying screens that can be combined as a system, if the integrating circuit 16 has the ability to sufficiently control the combination of the highest sensitivity and the coarse combination of the lowest sensitivity in a linear relationship, the detection circuit Resistance) R4-1 to R4-11
One type is enough, and conversely, if the detection circuit has that ability,
Integrating circuit 16A &;l'Jru R16-1-RR6-
R4;! One type of theme.

Furthermore, as is clear from the above formula, it is possible to change the value of the capacitor I)-016 in the integrating circuit 16Δ in terms of the sensitivity l, 71, and it is also possible to use the reference signal. However, it is possible to switch the above-mentioned C or some of them depending on circuit circumstances, and the present invention is not limited to the specific correspondence.

The present invention is not limited to the embodiments shown above and hereinafter, and may be modified without changing the gist thereof.

For example, Kino Ill S uses a barcode mark and a barcode reader to detect the type of film and intensifying screen, but a microswitch is installed in the cassette small holder, a dog is attached to the cassette, and a J, A mechanical mechanism for detecting the type of refilm and intensifying screen may also be used. In short, the operator must be aware of this and perform manual operation.
It is sufficient to have an automatic detection circuit that does not need to be used.

Further, in the above embodiment, the sensitivity switching of the detection circuit 4 and the correction of the output of the detection circuit 4 are both performed, but it is also possible to perform the adjustment by adjusting only one of them. That is, as mentioned above, the resistor in the detection circuit 4 and the resistor in the integrating circuit 16△, which is a component of the automatic exposure compensation circuit 16, have a proportional relationship with the predetermined constant A. be.

Also, the operation panel shows the area to be photographed, 9 body thickness values, and X#! 1. By using an X-ray control device that has selectors for selecting diagnostic conditions such as irradiation direction, grid type, and distance between film and focus, the optimal Wl is automatically set by selecting these selectors.
A method in which one condition (KV, lrI△, sec) is selected.
y program*+cd Radiograph
y) method. ) In general, once the diagnostic conditions are determined, the optimal combination of film and intensifying screen is determined. It is also possible to automatically search for this type of information and apply it to the present invention.

FIG. 5 shows an embodiment of the operation panel.

20 is a group of site selection switches; 21 is an organ/projection direction selection I;
R switch, which is displayed on the display panel 22), shooting direction, or other conditions (SFD, film/
Relative sensitivity of the intensifying screen, grid condition 1 rest thickness, etc.) are selected as appropriate. In addition, 23 (organ/imaging direction display change switch, 24 is a physique selection switch, allowing selection of various physiques from college students to children. 25 Gt body thickness correction switch, 26 KV/mAs, L) P switch, 27 is an mAS increase/decrease switch.

Further, in this example, an integrating circuit and a comparator are used in the circuit, but the processing can also be performed digitally using a high-speed arithmetic unit.

According to the apparatus of the embodiment described above, the following effects are achieved.

■If we can adopt the APR method, we can obtain the best X-ray photographs for interpretation (
Image strip f1 for q and automatic X-ray exposure control! It is enough to capture 11.

■Even when introducing new film and intensifying screens on the right side of use, all you have to do is mark the cassette, and you can save the time and expense of investigating and re-adjusting the sensho tokutake, which is required in the past. , total loss I/performance can also be improved.

■Since the operator is not forced to take any precautions or perform any operations, it is possible to prevent unnecessary X-ray exposure for retaking photographs due to operational errors, etc., and it also contributes to reducing the number of lines hanging, and also reduces operation noise. and other duties (e.g. determining the location of the withdrawn parts, correspondence with the inspected ministry, etc.)
In addition, since the method does not depend on the skill level of operating sounds, even an operator who is not an expert in the diagnosis method can obtain an X-ray photograph that provides accurate information.

[Effects of the Invention] According to the apparatus of the present invention as detailed above, it is possible to produce optimal X-ray self-a-ray M that is compatible with combinations of a plurality of films and intensifying screens without any difficulty in reducing operation noise. It is possible to perform radiation control.

[Brief explanation of drawings]

FIG. 1 shows a column I of an embodiment of the device of the present invention. 2 and 3 are schematic block diagrams, and FIG. 4 is a block diagram showing a practical example of a specific configuration of a detection circuit and an X-ray automatic exposure control circuit used therein, and FIG. 4 is a block diagram used to explain the present invention. Figure 5 is a diagram showing an example of the d5 stop-first-out and 'a-degree characteristics for a combination of a film and an intensifying screen.
It is a figure which shows an example of the operation panel for PR control. 1... XKA source, 2... Subject 4...
Detection circuit, 5...Cassette 6...Barcode mark, 7...Barcode reader 19...X-ray control device attorney P Rule Funi Chika Yudo Ogo Norio Figure 4

Claims (1)

[Claims] an X-ray source; an X-ray detection means for transmitting X-rays emitted from the X-ray source through a subject and detecting the transmitted X-rays;
a cassette for storing an X-ray film having an intensifying screen closely attached thereto for photographing a transmitted image of the subject by the transmitted X-ray;
An X-ray photographing apparatus comprising an automatic exposure control means for stopping X-ray exposure when the output from the radiation detection means exceeds a predetermined value, the type for detecting the type of the intensifying screen and the X-ray film. X-ray photography, characterized in that optimal control is performed according to the type of intensifying screen and X-ray film by adjusting the automatic exposure control means based on a detection means and an output from the type detection means. Device.