TWI781381B - X-ray imaging method and system thereof - Google Patents

Abstract

An X-ray imaging method includes following steps: (a) performing a first object imaging and obtaining a first object intensity signal by detecting an X-ray passing through a first object; (b) performing a baseline imaging, obtaining a baseline intensity signal by detecting the X-ray when the first object is not in a field of view; and (c) obtaining a first thickness of the first object by calculating the first object intensity signal, the baseline intensity signal, and a first attenuation coefficient of the first object.

Description

X-ray radiography method and system

The present invention relates to an X-ray radiography method and system, in particular to a method and system for measuring object thickness, mass, and absorbed dose by using X-rays.

Generally speaking, when X-ray images are currently used to measure the radiation dose of objects, specific dose measurement instruments must be used, such as high-priced equipment such as free chambers and proportional detectors. Such equipment is expensive. Equipping these dose measuring devices on the 2D image or computer tomography image will increase the cost of materials.

In addition, if a thermoluminescent dosimeter (Thermo Luminescent Dosimeter, TLD) is used for measurement, it may not be possible to obtain an instant dose due to the limitation of its principle. In addition, there are other methods of estimating radiation dose, such as using Monte Carlo simulation, but the method of using Monte Carlo simulation to calculate the dose and the thickness of an object requires the use of a high-end computer for calculation, and the calculation is quite time-consuming.

In order to solve the above problems, an aspect of the present disclosure provides an X-ray radiography method, which includes a plurality of steps: (a) performing a first object radiography, by detecting Measure an X-ray passing through a first object to obtain a first object intensity signal; (b) perform a reference radiography, and obtain a reference by detecting the X-ray when the first object is not in an imaging range an intensity signal; and (c) performing calculations on the first object intensity signal, the reference intensity signal and a first attenuation coefficient of the first object to obtain a first thickness of the first object.

Another aspect of the present invention is to provide an X-ray radiography method, which includes a plurality of steps: (a) performing a first object radiography, by detecting an X-ray passing through a first object, and obtaining a First object intensity signal; (b) perform a reference radiography, by detecting the X-ray when the first object is not in a radiography range, obtain a reference intensity signal; and (c) perform a second object irradiance Obtain a second object intensity signal by detecting the X-ray passing through a second object; (d) perform calculations from the first object intensity signal and the second object intensity signal to obtain a sample intensity signal , wherein the first object is a stage, the second object includes a sample and the stage; and (e) performing calculations from the sample intensity signal, the reference intensity signal and a sample attenuation coefficient to obtain a sample thickness.

Another aspect of the present invention is to provide an X-ray radiography system including an X-ray source, a detector and a processor. The X-ray source is configured to generate an X-ray. The detector is configured to detect the X-rays. A processor, coupled to the detector, is configured to execute an X-ray radiography method.

The X-ray radiography system and the method for estimating object information shown in the present invention perform object thickness calculation and radiation dose calculation through the signal value on the detector, and through this calculation, the object thickness and object thickness can be directly obtained from the image. The radiation dose absorbed in the body, this technology can be applied to provide the dose rate given by the current X-ray source, the cumulative dose and the average dose absorbed by the object in real time. In practical applications, the operator can The current radiation dose rate and the average dose absorbed by the object can be known by knowing the thickness of the object through X-ray shooting without additional expensive radiation detectors.

100, 200: X-ray Radiography Methods

110~130, 210~220, 620~640, 910~950: steps

x: sample thickness

k: pixel

OBJ: sample

DT: detector

SRX: ray source

PC: Processor

IMG: 2D projection image

TB: carrier

GRY: gray scale block

600: Method for Estimating Thickness of Objects Using X-rays

900: Calculation of sample absorbed dose method

FIG. 1 is a flowchart illustrating an X-ray radiography method according to an embodiment of the present invention.

Fig. 2 is a flowchart of an X-ray radiography method according to an embodiment of the present invention.

3A-3C are schematic diagrams illustrating an X-ray radiography system according to an embodiment of the present invention.

FIG. 4 is a schematic diagram showing X-ray energy-photon number according to an embodiment of the present invention.

Fig. 5 is a schematic diagram showing a thickness characteristic curve according to an embodiment of the present invention.

FIG. 6 is a flow chart illustrating a method for calculating the thickness of an object using X-rays according to an embodiment of the present invention.

FIG. 7 is a schematic diagram showing the attenuation coefficient according to an embodiment of the present invention.

Fig. 8 is a schematic diagram showing the absorption coefficient of a sample according to an embodiment of the present invention.

FIG. 9 is a schematic diagram illustrating a method for calculating absorbed dose of a sample according to an embodiment of the present invention.

The following description is a preferred implementation of the invention, and its purpose is to describe the basic spirit of the invention, but not to limit the invention. For the actual content of the invention, reference must be made to the scope of the claims that follow.

It must be understood that words such as "comprising" and "comprising" used in this specification are used to indicate the existence of specific technical features, values, method steps, operations, components and/or components, but do not exclude possible Add more technical characteristics, values, method steps, operation processes, components, components, or any combination of the above.

Words such as "first", "second", and "third" used in the claims are used to modify the elements in the claims, and are not used to indicate that there is an order of priority, an antecedent relationship, or an element An element preceding another element, or a chronological order in performing method steps, is only used to distinguish elements with the same name.

Please refer to FIGS. 1 , 2 , and 3A to 3C together. FIG. 1 is a flow chart of an X-ray radiography method 100 according to an embodiment of the present invention. FIG. 2 is a flow chart of an X-ray radiography method 200 according to an embodiment of the present invention. 3A-3C are schematic diagrams illustrating an X-ray radiography system according to an embodiment of the present invention.

Please refer to FIG. 3A first. In FIG. 3A , the X-ray radiography system at least includes an X-ray source SR, a detector DT and a processor PC.

In one embodiment, the X-ray source SR is used to generate X-rays.

In one embodiment, the detector DT is correspondingly disposed in the direction of the X-rays emitted by the X-ray source SR, for detecting X-rays passing through a medium (such as gas, solid, liquid).

In one embodiment, the processor PC is used for computing, and the processor PC can also be a microcontroller, a microprocessor, a digital signal processor, or an application-specific integrated circuit ( application specific integrated circuit (ASIC) or logic circuit, but not limited thereto.

The flow of the X-ray radiography method 100 will be described below through FIG. 1 .

In step 110, the X-ray source SR executes object imaging, and the detector DT obtains object intensity signals by detecting X-rays passing through the object.

In one embodiment, when the X-ray source SR performs object imaging, the detector DT receives the X-rays, generates an object intensity signal, and transmits the object intensity signal to the processor PC. The object intensity signal can be an X-ray image, The X-ray image can be presented in the form of a two-dimensional projection image IMG.

In one embodiment, the processor PC is coupled to the detector DT for receiving an object intensity signal generated by the detector DT, and the object intensity signal is related to the detected X-rays.

In step 120, the X-ray source SR executes the reference radiography, and the detector DT obtains the reference intensity signal by detecting the X-rays when the object is not in the radiography range.

In step 130, the processor PC estimates the thickness of the object based on the object intensity signal and the reference intensity signal.

In one embodiment, the object described in FIG. 1 may be a carrier. In another embodiment, the object described in FIG. 1 may be a combination of a stage and a sample (in other words, the combination of a sample placed on the stage is regarded as the object described in FIG. 1 ). In one embodiment, the object described in step 120 is not within the imaging range, which means that no stage and sample are placed in the imaging range, and the aerial shot in which the X-rays directly hit the detector DT is the reference imaging.

The following is a detailed description of the three types of aerial photography (hereinafter referred to as the object not in the photographing range), the object is the platform TB (hereinafter referred to as the first object), and the object is the combination of the platform TB and the sample OBJ (hereinafter referred to as the second object) photo situation. However, the definition of the first object and the second object in the present invention is not limited thereto.

In step 210, the X-ray source SR executes the reference radiography, and the detector DT obtains the reference intensity signal by detecting the X-rays when the first object is not in a radiography range.

In one embodiment, as shown in FIG. 3A, no object is placed within the imaging range, and the detector DT detects X-rays when the object is not in the imaging range. For example, no stage is placed on the detector DT There is no sample placed in the TB, and the baseline imaging procedure is performed by the X-ray radiography system to obtain the baseline intensity signal. The reference intensity signal is also called a blank image. The distribution of the number of X-ray photons within the energy range of the X-ray source is called the X-ray energy spectrum (as shown in Figure 4). The X-ray energy spectrum can be obtained through a known look-up table, measurement or calculation. The reference intensity signal obtained by the detector DT itself is a numerical value, which is the sum of the X-rays received by the detector DT under the X-ray energy spectrum.

In step 212, the first object (such as stage TB) is brought into the imaging range, as shown in FIG. 3B, the X-ray source SR executes the imaging of the first object, and the detector DT passes through the first object by detecting X-rays of the object to obtain the first object intensity signal.

More specifically, the X-ray source SR provides X-rays and performs imaging on the first object. Then the first object intensity signal is detected by the detector DT, and the first object intensity signal is sent to the processor PC.

In step 214, as shown in Figure 3C, the second object (such as the combination of the stage TB and the sample OBJ) is brought into the imaging range, the X-ray source SR executes the second object imaging, and the detector DT detects The X-ray passing through the second object is measured to obtain the intensity signal of the second object.

More specifically, the sample OBJ is placed on the stage TB, and the X-ray source SR provides an X-ray beam to take images on the stage TB and the sample OBJ. Then by detective The detector DT detects and obtains the second object intensity signal, and transmits the second object intensity signal to the processor PC. Wherein, the first object intensity signal and the second object intensity signal are X-ray photon signals, as shown in the two-dimensional projection image IMG in Fig. 3C, the gray-scale block GRY in the two-dimensional projection image IMG represents X-ray blocks of two objects.

In one embodiment, for example, the pixel k of the detector DT receives the lowest amount of X-rays, which means that the pixel k corresponds to the thickest position of the sample OBJ.

The above steps 210 to 214 are not limited in sequence. In one embodiment, the area where the detector DT receives the X-rays is called the irradiated area.

In step 220, the processor PC calculates the first object intensity signal and the second object intensity signal to obtain the sample intensity signal, and obtains the sample thickness x corresponding to the sample intensity signal according to the sample thickness characteristic curve. In one embodiment, the processor PC subtracts the first object intensity signal from the second object intensity signal to obtain the sample intensity signal.

In one embodiment, the processor PC obtains a sample thickness characteristic curve according to the reference intensity signal, the X-ray energy spectrum, and the attenuation coefficient of the sample.

In one embodiment, the thickness characteristic curve including the sample thickness characteristic curve, the first thickness characteristic curve, and the second thickness characteristic curve can be calculated by the following function (1) Beer-Lambert Law.

In one embodiment, the thickness characteristic curve is obtained based on the reference intensity signal, X-ray energy spectrum and attenuation coefficient calculation. Wherein, the operation includes a discrete (discrete) multiplication of the respective results obtained, and then summing up the results.

In one embodiment, a certain radiography parameter (including X-ray source energy and X-ray source tube current, or different types of filters can be added, etc.) is first air-shot a two-dimensional projection image without placing any objects, and then Put any object of known material, known Materials such as: water, experimental animals, acrylic, etc., objects that use the same imaging parameters for two-dimensional projection images (the following objects can refer to the first object or the second object) are photographed, and are captured by the detector DT The two-dimensional projected image signal is obtained, calculated by the following function (1), and the relational expression of the thickness of the placed object can be estimated from the signal strength value on the detector DT.

其中，符號

代表取自基準強度訊號任一像素之訊號強度，為X射線源所輸出X光能譜之特定能量i所對應的光子數量。符號μ代表為已知材質之物體之衰減係數(attenuation coefficient)，根據X光能量有不同之數值，此衰減係數可以為直線衰減係數(linear attenuation coefficient)。符號N₁代表放置物體後，由偵測器DT上所獲得的訊號強度。符號x代表像素位置之物體體厚。因此，藉由從影像偵測器DT獲得的訊號強度，處理器PC可透過厚度特徵曲線轉換為物體體厚資訊。

Among them, the symbol

Represents the signal intensity from any pixel of the reference intensity signal, and is the number of photons corresponding to the specific energy i of the X-ray energy spectrum output by the X-ray source. The symbol μ represents the attenuation coefficient of an object of known material, which has different values according to the X-ray energy, and the attenuation coefficient can be a linear attenuation coefficient. The symbol N ₁ represents the signal strength obtained from the detector DT after placing the object. The symbol x represents the thickness of the object at the pixel position. Therefore, with the signal strength obtained from the image detector DT, the processor PC can convert the thickness characteristic curve into object thickness information.

More specifically, the above-mentioned function (1) can be expanded into function (2). Figure 4 is a schematic diagram showing X-ray energy-photon number according to an embodiment of the present invention. The processor PC converts the X-ray energy spectrum information into Import Beer's Law. As shown in Figure 4, the horizontal axis in Figure 4 is the X-ray energy, and the vertical axis is the number of photons, where the X-ray energy spectrum information will vary according to the filter material, thickness and the maximum tube voltage of the X-ray tube. volume distribution. As shown in Figure 4, the solid line represents the energy spectrum information of the X-ray tube with a maximum tube voltage value of 50keV without an additional filter, the dotted line represents the energy spectrum information of a maximum tube voltage value of 50keV plus a 0.5mm aluminum filter, and the processor PC According to the selected parameters including X-ray tube energy, X-ray tube current or the combination of adding filters, the X-ray energy spectrum can be simulated, calculated or actually measured Estimate the spectral distribution of pixels. More specifically, by using the following function (2), the curve (thickness characteristic curve) of the object thickness and the object intensity signal as shown in FIG. 5 can be obtained. Fig. 5 is a schematic diagram showing a thickness characteristic curve according to an embodiment of the present invention.

其中，符號μ代表為物體之衰減係數，根據X光能量有不同之數值。符號i代表X光能譜之特定能量(由1keV至X射線源設定之最大管電壓數值)。符號x代表像素位置之物體體厚。

Among them, the symbol μ represents the attenuation coefficient of the object, which has different values according to the X-ray energy. The symbol i represents the specific energy of the X-ray energy spectrum (from 1keV to the maximum tube voltage value set by the X-ray source). The symbol x represents the thickness of the object at the pixel position.

Fig. 5 is a schematic diagram showing the thickness characteristic curve according to an embodiment of the present invention. The solid line in Fig. 5 is the thickness characteristic curve estimated by the function (2), the horizontal axis of Fig. 5 is the object intensity signal, and the vertical axis is the unit thickness (the unit is, for example, centimeter). Therefore, the processor PC can convert the detected object intensity signal through the thickness characteristic curve to obtain the object thickness. The thickness x of the object described in step 220 can be calculated by the function (2).

Please refer to FIG. 6. FIG. 6 is a flow chart illustrating a method 600 for calculating the thickness of an object using X-rays according to an embodiment of the present invention. Steps 610, 612, and 614 in FIG. 6 are respectively the same as those in FIG. 2 210, 212, and 214 are the same, so they will not be repeated here.

In one embodiment, the processor PC executes estimating a first thickness of the first object based on the first object intensity signal and the reference intensity signal. More specifically, in step 620, the processor PC performs operations according to the X-ray power spectrum of the reference intensity signal and the first attenuation coefficient of the first object to obtain the first thickness characteristic curve, and according to the first thickness characteristic curve and the object The intensity signal estimates a first thickness of the first object.

In one embodiment, the processor PC estimates the second thickness of the second object based on the second object intensity signal and the reference intensity signal. More specifically, in step 630, the processor PC performs calculations based on the X-ray power spectrum of the reference intensity signal and the second attenuation coefficient of the second object to obtain a second thickness characteristic curve, and according to the second thickness characteristic curve and the first The second object's second thickness is obtained by calculating the two object intensity signals.

In step 640, the processor PC subtracts the first thickness from the second thickness to obtain the sample thickness x. Wherein, the first object includes the stage TB, and the second object includes the sample OBJ and the stage TB.

In one embodiment, when the substance of the imaging material (such as the sample OBJ) is known, its density od can be known, and the thickness x of the sample OBJ can be obtained from the above function, plus the detector DT The sample size (pixel size) represented by the number of pixels can be used to calculate the image range quality of this shooting sample through the following function (3).

w _k =(psL*psW)*x * od..........(3)

其中，符號w_k為像素k上方厚度x所代表的樣本質量(weight)，單位為公斤或公克，符號psL為像素k所代表的樣本長度(單位為cm或m)，符號psW為像素k所代表的樣本寬度(單位為cm或m)，符號od為樣本密度(density)，單位為kg/m³或g/cm³。將所有偵測器DT上所有像素代表的樣本質量相加後，如函式(4)，可得照影範圍內所代表的樣本質量。

Among them, the symbol w _k is the sample mass (weight) represented by the thickness x above the pixel k, and the unit is kilogram or gram, the symbol psL is the sample length (cm or m) represented by the pixel k, and the symbol psW is the sample length represented by the pixel k. The representative sample width (in cm or m), the symbol od is the sample density (density), in kg/m ³ or g/cm ³ . After adding the sample masses represented by all the pixels on all detectors DT, as in function (4), the sample masses represented by the illumination range can be obtained.

Based on the above steps, the processor PC estimates the quality of the sample in the irradiated range based on the thickness x of the sample, the density of the sample and the area occupied by the sample in the irradiated range.

For example, after the processor PC receives the reference intensity signal (air-shot image), use the above function (1) to import the X-ray energy spectrum, the linear attenuation coefficient of the sample and the reference intensity signal to obtain the sample Thickness characteristic curve. Wherein, the attenuation coefficient is shown in Fig. 7, which is a schematic diagram showing the attenuation coefficient according to an embodiment of the present invention, the horizontal axis is X-ray energy (keV), and the vertical axis is the attenuation coefficient (μ). The unit of the attenuation coefficient is cm ^-1 . The X-ray radiography system obtains the sample thickness characteristic curve through the method of the above step 220, and obtains the sample thickness x corresponding to the sample intensity signal according to the sample thickness characteristic curve, and brings the sample thickness x into the function (3) and the sample density and image The sample pixel area represented by the upper gray scale block can be calculated to calculate the sample quality represented by this pixel area (sample pixel area x sample thickness x sample density = sample quality). When there are multiple sample pixel areas, all samples The sum of the masses is the sample mass.

In one embodiment, after the X-ray radiography system calculates the mass of the sample, it can further calculate the absorbed dose of the object. The following is an example of calculating the absorbed dose of the sample. However, when the values brought in by the following functions (5) and (6) are the parameters of the load bed TB and/or the sample OBJ, the load bed TB and/or The absorbed dose of the sample OBJ.

In one embodiment, the number of photons absorbed by the sample can be calculated by the following functions (5)-(6):

為X光能譜之特定能量i之X光穿過樣本厚度x且被樣本吸收後的剩餘光子數，單位為光子數(count)。

為一像素(pixel)的基準強度訊號，單位為光子數(count)，此像素例如為第3C圖中的像素k，i為X光能譜之特定能量，最大值為E單位 (keV)。

為X光為穿過樣本厚度x，於特定X光能量i該樣本的吸收光子數。

為樣本之吸收係數(absorption coefficient)，i為X光能譜之特定能量，其μ _en 根據X光能量i有不同之數值。關於樣本之吸收係數，請參閱第8圖，第8圖係依照本發明一實施例繪示樣本吸收係數之示意圖。第8圖的橫軸為X射線能量(keV)，縱軸為樣本之吸收係數(μ _en )。據此，處理器PC可依據基準強度訊號、樣本之吸收係數及樣本厚度運算得到被樣本吸收後剩餘光子數，將基準強度訊號減去被樣本吸收後剩餘光子數，藉此得知樣本的吸收光子數。 in,

It is the number of remaining photons after the X-ray with a specific energy i of the X-ray energy spectrum passes through the sample thickness x and is absorbed by the sample, and the unit is the number of photons (count).

is the reference intensity signal of a pixel (pixel), and the unit is photon count (count). This pixel is, for example, pixel k in FIG. 3C, i is the specific energy of the X-ray energy spectrum, and the maximum value is E unit (keV).

is the number of photons absorbed by the sample at a specific X-ray energy i when the X-ray passes through the sample thickness x.

is the absorption coefficient of the sample, i is the specific energy of the X-ray energy spectrum, and μ _en has different values according to the X-ray energy i . Regarding the absorption coefficient of the sample, please refer to FIG. 8, which is a schematic diagram showing the absorption coefficient of the sample according to an embodiment of the present invention. In Figure 8, the horizontal axis is the X-ray energy (keV), and the vertical axis is the absorption coefficient of the sample ( μ _en ). Accordingly, the processor PC can calculate the number of photons remaining after being absorbed by the sample based on the reference intensity signal, the absorption coefficient of the sample and the thickness of the sample, and subtract the number of photons remaining after being absorbed by the sample from the reference intensity signal to obtain the absorption of the sample photon count.

In one embodiment, the x-ray system computes the sample intensity signal above pixel k (as shown in FIG. 3C ) where the x-ray passes through the sample thickness x, and in this sample thickness x path, a specific energy of the x-ray energy spectrum is The number of absorbed photons of i can be converted into absorbed energy by function (7), and then the average absorbed dose Object Dose (unit: Gy, J/kG) can be calculated by function (8):

其中，符號E為X光射源最大管電壓。符號i為X光能譜之特定能量，最大值為E(單位：keV)。符號

為X光射源穿過樣本厚度x，於X光能譜之特定能量i的吸收光子數。符號Object weight為偵測器DT偵測之樣本質量，其單位為公斤。字串“detector pixel number”為第3A圖中二維投影影像IMG中的灰階區塊GRY的像素數量。因此，處理器PC可依據樣本的吸收光子數及X光能譜之能量範圍求出樣本厚度x對應之像素k的吸收能量，再計算偵測器 DT上所有像素上方樣本厚度所吸收的能量相加後，除以樣本質量即為樣本的平均吸收劑量。

Among them, the symbol E is the maximum tube voltage of the X-ray source. The symbol i is the specific energy of the X-ray energy spectrum, and the maximum value is E (unit: keV). symbol

is the number of absorbed photons at a specific energy i in the X-ray energy spectrum when the X-ray source passes through the sample thickness x. The symbol Object weight is the mass of the sample detected by the detector DT, and its unit is kilogram. The string "detector pixel number" is the pixel number of the gray scale block GRY in the 2D projection image IMG in FIG. 3A. Therefore, the processor PC can calculate the absorbed energy of the pixel k corresponding to the sample thickness x according to the number of absorbed photons of the sample and the energy range of the X-ray energy spectrum, and then calculate the relative energy absorbed by the sample thickness above all pixels on the detector DT After adding, divide by the sample mass to get the average absorbed dose of the sample.

In an embodiment, please refer to FIG. 9 , which is a flowchart illustrating a method 900 for calculating the absorbed dose of a sample according to an embodiment of the present invention.

In step 910, the processor PC receives a reference strength signal.

In step 920 , the processor PC calculates the number of remaining photons after the X-ray with a specific energy i in the X-ray energy spectrum passes through the sample thickness x and is absorbed by the sample according to the sample thickness x and the sample absorption coefficient. In one embodiment, the processor PC applies the function (3) to calculate the number of remaining photons after the X-ray with a specific energy i in the X-ray energy spectrum passes through the sample thickness x and is absorbed by the sample.

In step 930, the processor PC calculates the number of absorbed photons of the sample thickness x at a specific energy i in the X-ray spectrum. In one embodiment, the processor PC applies the function (6) to calculate the number of absorbed photons of the sample thickness x at a specific energy i of the X-ray spectrum.

In step 940, the processor PC converts the number of absorbed photons at a specific energy i in the X-ray spectrum into absorbed energy. In one embodiment, the processor PC applies the function (7) to calculate the absorbed energy.

In step 950, the processor PC sums the energy absorbed by the thickness of the sample above all the pixels on the detector DT and divides it by the mass of the sample to calculate the average absorbed dose of the sample. In one embodiment, the processor PC applies the function (8) to calculate the average absorbed dose of the sample.

In one embodiment, the X-ray radiography system can calculate the X-ray dose rate emitted by the X-ray source SR through the method 900. If the sample is simulated as a radiation detector (not shown), the free cavity of the radiation detector For example, if it is filled with air, it has been brought into functions (3) to (8) The known thickness x of the free cavity and the sample absorption coefficient (air absorption coefficient) are used to obtain the average absorbed dose of the radiation detector, which is the X-ray dose rate emitted by the X-ray source SR.

The X-ray radiography method and system shown in the present invention can calculate the thickness of the object and calculate the radiation dose through the signal value on the detector. Through this operation, the thickness, quality and the content of the object can be directly obtained from the image. The absorbed radiation dose, this technology can be applied to provide the dose rate given by the current X-ray source, the cumulative dose and the average dose absorbed by the object in real time. In practical applications, the operator can know the thickness and The current X-ray dose rate and the average dose absorbed by the object can be known without installing additional expensive radiation detectors.

The methods of the present invention, or specific forms or parts thereof, may exist in the form of program codes. The code may be contained in a physical medium, such as a floppy disk, compact disc, hard disk, or any other machine-readable (such as computer-readable) storage medium, or a computer program product without limitation in external form, wherein, When the program code is loaded and executed by a machine, such as a computer, the machine becomes a device for participating in the present invention. Code may also be sent via some transmission medium, such as wire or cable, optical fiber, or any type of transmission in which when the code is received, loaded, and executed by a machine, such as a computer, that machine becomes the Invented device. When implemented on a general-purpose processing unit, the code combines with the processing unit to provide a unique device that operates similarly to application-specific logic circuits.

Although the present invention has been disclosed above in terms of implementation, it is not intended to limit the present invention. Anyone skilled in this art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection of the present invention The scope shall be defined by the appended patent application scope.

100: X-ray Radiography Methods

110~130: Steps

Claims (8)

An X-ray radiography method, comprising a plurality of steps: (a) performing a first object radiography, and obtaining a first object image by detecting an X-ray passing through a first object; (b) performing a A reference image is obtained by detecting the X-ray when the first object is not in a range of images; and (c) a first image of the first object, the reference image, and the first object The attenuation coefficient is calculated to obtain a first thickness of the first object; wherein the step (c) of obtaining the first thickness includes: (c-1) an X-ray energy spectrum of the reference image and the first attenuation coefficient performing calculations to obtain a first thickness characteristic curve; and (c-2) performing calculations from the first thickness characteristic curve and the first object image to obtain the first thickness; (d) performing a second object imaging, Obtaining a second object image by detecting the X-rays passing through a second object; and (e) performing calculations from the second object image, the reference image, and a second attenuation coefficient of the second object, obtaining a second thickness of the second object; (f) subtracting the first thickness from the second thickness to obtain a sample thickness; (g) performing calculations from the reference image, the sample thickness and a sample absorption coefficient, obtaining a remaining photon number; wherein the first object is a stage, the second object includes a sample and the stage; and (h) Performing calculations on the reference image and the remaining photon count to obtain an absorbed photon count of the sample. The X-ray radiography method described in item 1 of the scope of the patent application, wherein the first thickness characteristic curve is obtained through a function, and the function includes:

Among them, the symbol E is a maximum tube voltage of an X-ray source, the symbol μ represents the first attenuation coefficient, the symbol i represents a specific energy of the X-ray energy spectrum, and the symbol x represents the thickness of an object at a pixel position . The X-ray radiography method described in claim 1, wherein the step (e) of obtaining the second thickness includes: (e-1) an X-ray energy spectrum of the reference image and the second attenuation coefficient performing calculations to obtain a second thickness characteristic curve; and (e-2) performing calculations based on the second thickness characteristic curve and the second object image to obtain the second thickness. The X-ray radiography method described in item 3 of the scope of the patent application, wherein the second thickness characteristic curve is obtained through a function, and the function is:

Among them, the symbol E is a maximum tube voltage of an X-ray source, the symbol μ represents the second attenuation coefficient, the symbol i represents a specific energy of the X-ray energy spectrum, and the symbol x represents the thickness of an object at a pixel position . An X-ray radiography method, comprising a plurality of steps: (a) performing a first object radiography, and obtaining a first object image by detecting an X-ray passing through a first object; (b) performing a reference imaging, by detecting the X-ray when the first object is not in an imaging range, to obtain a reference image; and (c) performing a second object imaging, by detecting the X-ray to obtain a second object image; (d) perform calculations on the first object image and the second object image to obtain a sample image, wherein the first object is a stage, and the second object includes a sample and the stage; and (e) calculate a sample thickness from the sample image, the reference image and a sample attenuation coefficient; wherein the step (e) of obtaining the sample thickness includes: (e-1) by An X-ray energy spectrum of the reference image and the sample attenuation coefficient are calculated to obtain a sample thickness characteristic curve; and (e-2) the sample thickness is obtained from the sample thickness characteristic curve and the sample image; (f) by calculating the reference image, the sample thickness and a sample absorption coefficient to obtain a remaining photon number; and (g) Perform calculations on the reference image and the remaining photon count to obtain an absorbed photon count of the sample. The X-ray radiography method described in item 5 of the scope of the patent application further includes step (h): the number of absorbed photons of the sample is calculated by a function to obtain an absorption energy of the sample, and the function is:

Among them, the symbol E is a maximum tube voltage of an X-ray source, the symbol i is a specific energy of an X-ray energy spectrum, and the symbol

is the number of absorbed photons at a specific energy i of the X-ray energy spectrum when the X-ray source passes through the sample thickness. The X-ray radiography method described in item 5 of the scope of the patent application further includes step (i): performing calculations based on the thickness of the sample, a density of the sample and an area occupied by the sample in the radiography range, A mass of the sample in the imaging range is obtained. An X-ray radiography system, comprising: an X-ray source configured to generate an X-ray; a detector configured to detect the X-ray; and a processor coupled to the detector, the processor It is configured to implement any one of items 1 to 7 of the scope of the patent application.

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