Control Method and Device for Exposure Gate Cut-off of High-Voltage Generator

Abstract

The present invention provides a control method and device for exposure cut-off of a high-voltage generator. The method at least includes the following steps: obtaining exposure correction coefficients of different working conditions of the high-voltage generator in different exposure environments, and constructing a database according to each exposure correction coefficient; the working conditions include acceleration voltage and filament current; performing a correction process before exposure control according to the database and the exposure working conditions of the high-voltage generator; controlling the high-voltage generator to perform exposure under the exposure working conditions based on the correction result, and controlling the high-voltage generator to perform exposure cut-off. Performing correction before exposure control can effectively avoid the influence of errors, thereby accurately controlling exposure cut-off, and further making the result of image acquisition more accurate.

Description

Technical Field

[0001] The present invention relates to the technical field of exposure control, and particularly to a control method and device for exposure interruption of a high-voltage generator. Background Art

[0002] Flat panel detectors are a new type of X-ray imaging detection technology, known for features such as fast imaging speed and high resolution, and are widely used in medical detection, non-destructive testing, security inspection, anti-terrorism and other fields. During the process of a flat panel detector receiving exposure for imaging, users need to select the line quality and dose of exposure according to factors such as the thickness and density of the object being photographed, with a high degree of dependence on experience and being difficult to control.

[0003] Currently, traditional AEC (Automatic Exposure Control) all detects the exposure dose by means of an ionization chamber (mainly including gaseous ionization chambers and solid-state ionization chambers), and as the exposure dose increases, the output signal voltage increases linearly. The high-voltage generator detects this output signal voltage in real time, and when this voltage reaches the set threshold voltage, the high-voltage generator interrupts the exposure. However, traditional AEC requires adding an ionization chamber on the surface of the flat panel detector, and the ionization chamber is connected to the high-voltage generator through a dedicated cable, with both the structural complexity and cost being relatively high.

[0004] In recent years, DAEC based on panel scanning developed by some manufacturers has emerged, reducing the structural complexity and cost. However, the detector needs to transmit the interruption signal to the high-voltage generator through wired transmission or wireless transmission. There is a delay response time from when the high-voltage receives the interruption signal to when the exposure actually stops, and there is also a certain delay time for the signal to be transmitted in the link, both of which bring errors to the exposure dose obtained by automatic exposure control. Summary of the Invention

[0005] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a control method and device for exposure interruption of a high-voltage generator, which is used to solve the problem of inaccurate control in the prior art.

[0006] To achieve the above purpose and other related purposes, the present invention provides a control method for exposure interruption of a high-voltage generator, and the method at least includes the following steps:

[0007] Obtain the exposure correction coefficients of the high-voltage generator under different working conditions during exposure, and construct a database according to each exposure correction coefficient; the working conditions include the accelerating voltage of the high-voltage generator and the filament current of the high-voltage generator;

[0008] Perform a correction process before exposure control according to the database and the exposure working conditions of the high-voltage generator;

[0009] Based on the calibration result, control the high-voltage generator to perform exposure under the exposure working conditions, and control the high-voltage generator to perform exposure interruption.

[0010] Preferably, the process of obtaining the calibration coefficients of the high-voltage generator under different working conditions during exposure is as follows:

[0011] Preset different working conditions of the high-voltage generator during exposure;

[0012] Based on each working condition, conduct exposure experiments to obtain the corresponding exposure calibration coefficients;

[0013] Construct a database according to the obtained exposure calibration coefficients.

[0014] Preferably, the working conditions further include the distance from the ray source focus to the detector and / or the type of loading filtration.

[0015] Preferably, the database is stored in the form of a data table.

[0016] Preferably, the calibration process before exposure control is as follows:

[0017] Set the working conditions of the high-voltage generator for exposure and the initial exposure dose threshold;

[0018] Obtain the exposure calibration coefficient corresponding to the exposure working conditions through the database;

[0019] Calibrate the initial exposure dose threshold according to the exposure calibration coefficient corresponding to the exposure working conditions to obtain the calibration result.

[0020] Preferably, the calibration result is to update the exposure dose threshold.

[0021] Preferably, during exposure, when the exposure interruption condition is reached, control the high-voltage generator to perform exposure interruption, and the exposure interruption condition is that the exposure dose reaches the updated exposure dose threshold.

[0022] Preferably, generate an interruption instruction according to the exposure interruption determination condition and the link delay time, and control the detector to close the exposure window according to the interruption instruction.

[0023] Preferably, it further includes image acquisition of the irradiation field within the exposure window.

[0024] To achieve the above object and other related objects, the present invention also provides a control device for exposure interruption of a high-voltage generator, characterized in that the device includes a processor and a memory, and a computer program that can run on the processor is stored on the memory. When the computer program is executed by the processor, the steps of the above control method for exposure interruption of the high-voltage generator are implemented.

[0025] As described above, a control method and device for exposure gating of a high-voltage generator according to the present invention have the following beneficial effects:

[0026] The control method and device for exposure gating of a high-voltage generator according to the present invention obtain exposure correction coefficients of the high-voltage generator under different working conditions, and construct a database according to the exposure correction coefficients; the working conditions include acceleration voltage and filament current; a correction process before exposure control is performed according to the database and the exposure working conditions of the high-voltage generator; based on the correction result, the high-voltage generator is controlled to perform exposure under the exposure working conditions, and the high-voltage generator is controlled to perform exposure gating. It can effectively avoid the influence of errors, thereby improving the control accuracy of automatic exposure, that is, accurately controlling exposure gating, and further making the result of image acquisition more accurate. In addition, based on logical function control, the control method is highly programmable, which is convenient for adding functions such as logical selection. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It shows a schematic flow chart of the control method for exposure gating of the high-voltage generator of the present invention Figure 1 。

[0028] Figure 2 It shows a schematic flow chart of the control method for exposure gating of the high-voltage generator of the present invention Figure 2 。 DETAILED DESCRIPTION OF THE INVENTION

[0029] The following specific examples illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0030] Please refer to Figure 1 - Figure 2 It should be noted that the diagrams provided in this embodiment only illustrate the basic concept of the present invention in a schematic manner. Therefore, only the components related to the present invention are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The type, quantity, and ratio of each component in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0031] The present invention places the detector in a medical system (including systems using flat panel detectors such as DR, CT, and security scanners). The detector is connected to a computer through a router to achieve command interaction and image transmission; at the same time, the detector is wirelessly connected to a high-voltage control box, and the high-voltage control box is connected to a high-voltage generator; or the detector is directly wirelessly connected to the high-voltage generator.

[0032] Method Embodiment:

[0033] The control method for the exposure cutoff of the high-voltage generator of the present invention is as Figure 1 shown, and at least includes the following steps:

[0034] S1. Obtain the exposure correction coefficients under different working conditions during the exposure of the high-voltage generator, and construct a database according to each exposure correction coefficient; the working conditions include the accelerating voltage of the high-voltage generator and the filament current of the high-voltage generator;

[0035] As a more preferred embodiment, the working conditions may further include the distance from the ray source focus to the detector (SID) and / or the type of load filtration, etc.; different SIDs and different types of load filtration will also affect the exposure correction coefficient. Otherwise, the types of load filtration are filtrations of different materials (such as aluminum, copper), etc. Based on more accurate working conditions, more accurate exposure correction coefficients can be obtained, and thus more accurate exposure control results can be obtained.

[0036] In the embodiment of the present invention, the process of obtaining the correction coefficients under different working conditions during the exposure of the high-voltage generator is as follows:

[0037] S11. Preset different working conditions during the exposure of the high-voltage generator;

[0038] In the embodiment of the present invention, taking the working conditions that affect the exposure of the high-voltage generator including the accelerating voltage of the high-voltage generator and the filament current of the high-voltage generator as an example to introduce the process of the control method for the exposure cutoff of the high-voltage generator; the accelerating voltage is specifically the accelerating voltage applied by the high-voltage generator to the X-ray tube. Generally, the accelerating voltage applied by the high-voltage generator to the X-ray tube is 40 kV to 150 kV, and the filament current is 10 mA to 500 mA.

[0039] The setting method for different working conditions is: the accelerating voltage is set according to the first interval, and the filament current is set according to the second interval. Among them, the first interval may be the same as the second interval or may not be the same.

[0040] For example, if the first interval is 2, the accelerating voltages are kV1 (40 kV), kV2 (42 kV), kV1 (44 kV),...; if the second interval is 5, the filament currents are mA1 (10 mA), mA2 (15 mA), mA3 (20 mA),...

[0041] S12. Conduct exposure experiments based on each working condition to obtain the corresponding exposure correction coefficients;

[0042] As a preferred embodiment of the present invention, the high-voltage generator can be made to conduct exposure experiments under each working condition according to the work experience of the staff, and through the comparison and adjustment of the experimental results, the corresponding exposure correction coefficients can be obtained. This embodiment depends on the rich experience of the staff and the process is simple.

[0043] As another preferred embodiment of the present invention, it is also possible to first let the high-voltage generator perform an exposure experiment under working conditions, obtain the exposed image, and perform fitting according to the gray value of the image to obtain the corresponding exposure correction coefficient. This embodiment requires an image analysis and processing process and relies on intelligent calculation.

[0044] The above two specific implementations of obtaining the exposure correction coefficient are both prior arts, and the present invention will not introduce them further.

[0045] Specifically, in this embodiment, for example, the exposure correction coefficient when the accelerating voltage is kV1 (40 kV) and the filament current is mA1 (10 mA) is K11, the exposure correction coefficient when the accelerating voltage is kV1 (40 kV) and the filament current is mA2 (15 mA) is K12,..., the exposure correction coefficient when the accelerating voltage is kV2 (42 kV) and the filament current is mA1 (10 mA) is K21,..., the exposure correction coefficient when the accelerating voltage is kV3 (44 kV) and the filament current is mA1 (10 mA) is K31,....

[0046] S13. Construct a database according to the obtained exposure correction coefficients; the database is stored in the form of a data table;

[0047] In the embodiment of the present invention, the database constructed by converging each working condition and the corresponding exposure correction coefficient is as follows:

[0048]

[0049] S2. Perform a pre-exposure control correction process according to the database and the exposure working conditions of the high-voltage generator;

[0050] The essence of this step is to adjust the high-voltage generator through the exposure correction coefficient to obtain an updated exposure dose threshold under the exposure working conditions.

[0051] In the embodiment of the present invention, after the detector is powered on and the preset is completed, first turn off the exposure control, set the high-voltage generator under the exposure working conditions, then obtain the exposure correction coefficient corresponding to the exposure working conditions in the exposure environment through the database, and input the exposure correction coefficient in the exposure environment into the detector to adjust the initial exposure dose threshold to obtain an updated exposure dose threshold. Therefore, in the embodiment of the present invention, the correction result is the updated exposure dose threshold.

[0052] For example, the exposure operating condition has an accelerating voltage of kV2 (42 kV) and a filament current of mA1 (10 mA), and the corresponding exposure correction coefficient is K21; while the initial exposure dose threshold set by the high-voltage generator is Y0. Then, during the correction process of the exposure operating condition, even if the exposure correction coefficient K21 corrects the exposure dose threshold Y0, the obtained exposure dose threshold after correction is Y1.

[0053] S3. Control the high-voltage generator to perform exposure under the exposure operating condition, and control the high-voltage generator to perform exposure interruption;

[0054] The high-voltage generator performs exposure under the exposure operating condition. When the exposure interruption condition is reached, control the high-voltage generator to perform exposure interruption; wherein, the exposure interruption condition is that the exposure dose reaches the updated exposure dose threshold. Specifically, when the detector counts that the exposure dose reaches the updated exposure dose threshold, control the high-voltage generator to perform exposure interruption. The exposure operating condition here is the operating condition for actual exposure control.

[0055] When determining the irradiation field through multiple local fields of view, the exposure dose exceeding the updated dose threshold means that the gray values of multiple local fields of view exceed the set dose threshold according to the set logical relationship, that is, compare and judge the gray values of multiple local fields of view with the set dose threshold according to the preset logical relationship.

[0056] In the embodiment of the present invention, the set logical relationship includes weighted average, logical AND, or logical OR; when the set logical relationship is logical AND, the exposure dose reaching the updated exposure dose threshold actually means that the gray values of multiple local fields of view all need to exceed the updated dose threshold; that is, the minimum gray value among the gray values of multiple local fields of view exceeds the updated dose threshold; when the set logical relationship is logical OR, the exposure dose reaching the updated exposure dose threshold actually means that the gray value of any one local field of view exceeds the updated dose threshold; that is, the maximum gray value among the gray values of multiple local fields of view exceeds the updated dose threshold; when the set logical relationship is weighted average, the exposure dose reaching the updated exposure dose threshold actually means calculating the mean value according to the weight of each local field of view, and the calculated mean value result exceeds the updated dose threshold.

[0057] The present invention takes into account that there is a link delay in the actual information transmission process between the detector and the high-voltage generator. Therefore, it is necessary to issue an interruption instruction before the detector exposure window should actually be closed to ensure precise control of the detector to close the exposure window and achieve exposure interruption.

[0058] Therefore, the present invention generates an interruption instruction according to the exposure interruption determination condition and the link delay time, and controls the detector to close the exposure window according to the interruption instruction.

[0059] Specifically, when the exposure dose reaches the updated exposure dose threshold, the exposure window needs to be closed. If the shutter cut-off instruction is closed after meeting the exposure shutter cut-off determination condition t1, and the link delay time is t2, where t2 < t1, then the high-voltage generator needs to be controlled to perform exposure shutter cut-off at the moment of t1 - t2, so that the detector can close the exposure window after t1.

[0060] As a preferred embodiment of the control method for exposure shutter cut-off of the high-voltage generator of the present invention, as Figure 2 shown, the control method further includes:

[0061] S4, performing image acquisition on the irradiation field within the exposure window.

[0062] The detector of the present invention is based on an intelligently recognized irradiation field, and under the condition of accurately controlling the exposure shutter cut-off of the high-voltage generator, accurate image acquisition of the area to be measured is achieved.

[0063] The control method and device for exposure shutter cut-off of the high-voltage generator of the present invention obtain the exposure correction coefficients of the high-voltage generator under different working conditions, and construct a database according to each exposure correction coefficient; perform a correction process before exposure control according to the database and the exposure working conditions of the high-voltage generator; control the high-voltage generator to perform exposure under the exposure working conditions based on the correction result, and control the high-voltage generator to perform exposure shutter cut-off. Performing correction before exposure control can effectively avoid the influence of errors, thereby accurately controlling the exposure shutter cut-off, and further making the result of image acquisition more accurate.

[0064] Device embodiment:

[0065] To achieve the above technical purpose, the present invention also provides a control device for exposure shutter cut-off of a high-voltage generator. The device includes a processor and a memory. A computer program that can run on the processor is stored on the memory. When the computer program is executed by the processor, the steps of the above control method for exposure shutter cut-off of the high-voltage generator are implemented.

[0066] Since the steps of the control method for exposure shutter cut-off of the high-voltage generator have been introduced in detail in the method embodiment, this embodiment will not be elaborated here.

[0067] In summary, for the control method and device of the exposure shutter of the high-voltage generator according to the present invention, the exposure correction coefficients of the high-voltage generator under different working conditions are obtained, and a database is constructed based on each exposure correction coefficient; the working conditions include the acceleration voltage and the filament current; a correction process before exposure control is performed according to the database and the exposure working conditions of the high-voltage generator; based on the correction result, the high-voltage generator is controlled to perform exposure under the exposure working conditions, and the high-voltage generator is controlled to perform exposure shutter. It can effectively avoid the influence of errors, thereby accurately controlling the exposure shutter, and further making the result of image acquisition more accurate. Therefore, the present invention effectively overcomes various disadvantages in the prior art and has high industrial utilization value.

[0068] The above embodiments are only illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A control method for the exposure cut-off of a high-voltage generator, characterized in that, The method at least includes the following steps: Obtain the exposure correction coefficients of the exposure dose thresholds under different working conditions during the exposure of the high-voltage generator, and construct a database based on each exposure correction coefficient; the working conditions include the acceleration voltage of the high-voltage generator and the filament current of the high-voltage generator; Perform a correction process before exposure control according to the database and the exposure working conditions of the high-voltage generator; wherein, set the working conditions of the high-voltage generator exposure and the initial exposure dose threshold; obtain the exposure correction coefficient corresponding to the exposure working conditions in the exposure environment through the database; correct the initial exposure dose threshold according to the exposure correction coefficient corresponding to the exposure working conditions in the exposure environment to obtain an updated exposure dose threshold; Control the high-voltage generator to perform exposure under the exposure working conditions based on the correction result, and control the high-voltage generator to perform exposure interruption; wherein, when the detector counts that the exposure dose reaches the updated exposure dose threshold, control the high-voltage generator to perform exposure interruption.

2. The control method for the exposure shutter cut-off of the high-voltage generator according to claim 1, characterized in that, The process of obtaining the correction coefficients under different working conditions during the exposure of the high-voltage generator is as follows: Preset different working conditions during the exposure of the high-voltage generator; Perform exposure experiments based on each working condition to obtain the corresponding exposure correction coefficients; Construct a database according to the obtained exposure correction coefficients.

3. The control method for the exposure cut-off of the high-voltage generator according to claim 2, characterized in that, The working conditions further include the distance from the ray source focus to the detector and / or the type of added filtration.

4. The control method for the exposure cutoff of the high-voltage generator according to claim 2, characterized in that, The database is stored in the form of a data table.

5. The control method for the exposure cut-off of the high-voltage generator according to claim 1, characterized in that, During exposure, when the exposure interruption condition is reached, control the high-voltage generator to perform exposure interruption, and the exposure interruption condition is that the exposure dose reaches the updated exposure dose threshold.

6. The control method for the exposure cut-off of the high-voltage generator according to claim 5, characterized in that, Generate an interruption instruction according to the exposure interruption condition and the link delay time, and control the detector to close the exposure window according to the interruption instruction.

7. The control method for the exposure cutoff of the high-voltage generator according to claim 1, characterized in that, It further includes image acquisition of the irradiation field within the exposure window.

8. A control device for the exposure cut-off of a high-voltage generator, characterized in that, The device includes a processor and a memory, and a computer program that can run on the processor is stored on the memory. When the computer program is executed by the processor, it implements the steps of the control method for exposure interruption of the high-voltage generator according to any one of claims 1-7.

Images