JP2002296022A - Mass measuring method by x-ray and x-ray mass measuring instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate simplify mass measuring of a measured object by calculating the mass of the measured object according to a prescribed formula based on the dosage of X-rays transmitting through the measured object. SOLUTION: The measured object W put between an X-ray generation part 3 and an X-ray detection part 4 is exposed to X-rays emitted from the generation part 3. Transmitted X-rays transmitting through the exposed object W are detected by the detection part 4. The mass of the object W is calculated for each unit transmission area according to the prescribed formula based on the detected dosage I of the transmitting X-rays. The unit mass of the object W calculated for each unit transmission area is integrated over all the transmission areas of transmitting X-rays to calculate the whole mass of the object W.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to raw meat, fish,
The present invention relates to a mass measuring method and a mass measuring device for measuring the mass of an object to be measured of each type, such as processed foods and pharmaceuticals, and in particular, to measure the amount of X-ray transmitted when the object is irradiated with X-rays. The present invention relates to a mass measuring method and a mass measuring device for measuring the mass of an object.

[0002]

2. Description of the Related Art Conventionally, there are various measuring methods for measuring an object, but a measuring method using X-rays is not well known. Here, as a measuring method using X-rays, there is a method for measuring the amount of Fe plating adhered on an Fe-plated stainless steel sheet described in JP-A-6-34352.

In this method, a stainless steel sheet before and after Fe plating is analyzed by a fluorescent X-ray method to measure the amount of Fe plating attached. As is well known, the fluorescent X-ray method is an analysis method using X-rays (fluorescent X-rays) of a specific wavelength that is re-emitted from an object when irradiated with X-rays on a metal. This is a method of examining elemental components by fluorescent X-rays obtained by irradiation.

However, in the above-mentioned measuring method, the fluorescent X
Since the line is analyzed, only the amount of Fe plating adhered to the surface of the metal material can be measured, and the mass of the entire material cannot be determined.

Further, as a document relating to X-rays and weight measurement, there is an X-ray foreign substance detecting device with a weighing function disclosed in Japanese Patent Application Laid-Open No. 9127017.

Originally, an X-ray foreign matter detector radiates X-rays to an object to be measured of each type, for example, raw meat, fish, processed food, medicine, etc., which are sequentially conveyed on a conveying line, and the radiated X-rays are irradiated with the X-rays. This is a device that detects whether or not a foreign substance such as metal, glass, stone, or bone is mixed in an object from the amount of X-ray transmission.

In the apparatus described in the above-mentioned publication, a weighing device is provided on the carry-out conveyor separately from the X-ray irradiator and the X-ray detecting unit for detecting foreign matter, and the weight of the object to be measured after foreign matter detection is measured. .

However, in the above-mentioned apparatus, the weight measurement is processed separately from the foreign matter detection by X-rays. That is, since the measuring device is provided separately from the X-ray irradiator and the X-ray detecting unit, the device becomes large-scale and the manufacturing cost increases. In addition, since a weighing device is separately provided, if the weighing device breaks down, weighing cannot be performed.

[0009]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a method for measuring the amount of X-rays transmitted through an object to be measured. By calculating the mass of the object to be measured from the following formula, the mass measurement of the object to be measured is facilitated and simplified. In particular, there is a need to reduce the space or size of the entire apparatus by performing mass measurement by software processing without providing a mass measuring device for the object to be measured. In addition, this eliminates the need for a mass measuring device, thereby preventing cost increase.

It is another object of the present invention to divide a transmission area of an object to be measured, thereby enabling mass measurement for each of the divided areas. Thus, the mass distribution of each divided region of the device under test is clarified.

Still another object of the present invention is to derive measurement parameters for each object to be measured, thereby facilitating the setting of the measurement parameters, thereby further facilitating mass measurement of the object to be measured. The purpose is to simplify the operation.

It is still another object of the present invention to improve the accuracy of inspection for a missing part of an object to be measured by combining foreign matter detection by X-rays. Another object of the present invention is to simultaneously perform the mass measurement and the thickness measurement of the object W based on the transmitted X-ray dose of the same object W. As a result, it is possible to reduce or speed up the processing time of foreign object detection and mass measurement on the same object. In particular, the object of the present invention is to further reduce or speed up the processing time by performing a foreign matter detection process before mass measurement and determining whether or not there is mass measurement based on the detection result.

[0013]

Next, means for solving the above problems will be described with reference to the drawings corresponding to the embodiments. The mass measuring method by X-ray according to claim 1 is
X-rays are emitted from the X-ray generation unit 3 to the measurement target W between the X-ray generation unit 3 and the X-ray detection unit 4, and the transmitted X-rays transmitted through the irradiated measurement target W are transmitted. X-rays are detected by the X-ray detection unit 4, and the mass of the object W is calculated for each unit transmission area from the following equation based on the detected transmitted X-ray dose I. A unit mass of each unit transmission region of the measurement object W is integrated over the entire transmission region of the transmission X-ray to calculate a total mass M of the measurement object W.

[0014]

(Equation 5)

[0015] However, I ₀ is the exposure X-ray dose, I is transmitted X-rays, x is the measured object W thickness, mu _m is the mass absorption coefficient, [rho is the density of the object to be measured W, M whole mass.

According to a second aspect of the present invention, there is provided a method for measuring mass by X-rays, comprising:
To Wd, X-rays are emitted from the X-ray generation unit 3, and the transmitted X-rays that have passed through the exposed objects Wa to Wd are
Based on the transmitted X-ray dose I detected by the X-ray detection unit 4, the measured objects Wa to W
The mass of d is calculated from the following formula, and the calculated unit mass of each of the measurement objects Wa to Wd for each of the unit transmission regions is calculated as a total transmission region of transmission X-rays transmitted through the measurement objects Wa to Wd. Are divided into a plurality of divided transmission areas DA to DD
And calculating the total mass M of the DUT for each of the divided transmission areas DA to DD.

[0017]

(Equation 6)

[0018] However, I ₀ is the exposure X-ray dose, I is transmitted X-rays, x is the measured object W thickness, mu _m is the mass absorption coefficient, [rho is the density of the object to be measured W, M total mass

According to a third aspect of the present invention, there is provided a mass measuring method using X-rays, wherein the irradiation X-ray dose I ₀ for irradiating the object to be measured W is set in the mass measuring method according to the first or second embodiment. characterized in that by selecting the object to be measured W, extracts the composition elements, based on the set the exposure X-rays I ₀ and the extracted the composition element, derives the mass absorption coefficient mu _m And

According to a fourth aspect of the present invention, there is provided a mass measuring method using X-rays, wherein the object to be measured W is composed of a plurality of types of the composition elements. The irradiation X-ray for irradiating the object W is set, the object to be measured W is selected, the plurality of types of constituent elements are extracted, and the set irradiation X-ray and the extracted X-ray are set. based on each composition element, and wherein the averaging to derive the mass absorption coefficient mu _m for each said set forming element.

According to a fifth aspect of the present invention, there is provided an X-ray
At least the mass absorption coefficient μ of the DUT W _mAnd the object to be measured
Exposure X dose I to W₀Measurement parameters consisting of
Measurement parameter setting unit 10 to be set, and
On the other hand, the set exposure X dose I₀X-rays
Penetrates the X-ray generating unit 3 and the irradiated object W
An X-ray detection unit 4 for detecting transmitted X-rays;
Derived transmission data y based on the transmission X-ray obtained
A data processing unit for performing transmission, and a transmission X-ray dose from the transmission data y.
A transmitted X-ray dose calculation unit for calculating I,
Based on the measurement parameters and the transmitted X-ray dose I,
A mass calculation unit for calculating the total mass M of the measured object W
It is characterized by doing.

According to a sixth aspect of the present invention, there is provided the X-ray mass measuring apparatus according to the fifth aspect, wherein the mass calculating unit calculates the mass of each of the unit transmission regions of the DUT by the following equation. The method is characterized in that a unit mass is calculated and integrated over the entire transmission region of the transmitted X-rays transmitted through the object W to calculate the overall mass M of the object W.

[0023]

(Equation 7)

[0024] However, I ₀ is the exposure X-ray dose, I is transmitted X-rays, x is the measured object W thickness, mu _m is the mass absorption coefficient, [rho is the density of the object to be measured W, M whole mass.

According to a seventh aspect of the present invention, there is provided the X-ray mass measuring apparatus according to the fifth or sixth aspect, further comprising a foreign matter detecting unit for detecting a foreign matter in the object to be measured W from the transmission data y. It is characterized by doing.

According to an eighth aspect of the present invention, there is provided the X-ray mass measuring apparatus according to the seventh aspect, wherein the mass calculation unit is configured to detect when no foreign matter is detected in the object W by the foreign matter detection unit. Only the whole mass M of the object W is calculated.

[0027] X-ray mass measuring unit according to claim 9, wherein sets a measurement parameter consisting exposure X-ray dose I ₀ for at least the mass absorption coefficient of the object Wa to Wd mu _m and the measured object Wa to Wd A measurement parameter setting unit 10;
The set exposure X is applied to the measured objects Wa to Wd.
An X-ray generation unit 3 that emits X-rays of a dose I ₀ , an X-ray detection unit 4 that detects transmitted X-rays that pass through the irradiated objects Wa to Wd, and an X-ray detection unit 4 And a data processing unit that derives transmission data y based on the transmission X-rays obtained from the plurality of divided transmission areas DA obtained by dividing all transmission areas of the transmission X-rays that have passed through the measurement objects Wa to Wd. ~ DD
A data extraction unit for extracting the transparent data y
A transmission X-ray dose calculation unit that calculates a transmission X-ray dose I from the transmission data y, and the set measurement parameter, the transmission X-ray dose I, and a thickness x of each unit area of the device under test W, A mass calculation unit for calculating the total mass M of the objects to be measured Wa to Wd for each of the divided transmission areas DA to DD.

According to a tenth aspect of the present invention, there is provided the X-ray mass measuring apparatus according to the ninth aspect, wherein the mass calculating section calculates the unit transmission area of the measured objects Wa to Wd by the following equation. Is calculated for each of the divided transmission areas DA to DD, and is integrated for each of the divided transmission areas DA to DD.
It is characterized in that the mass M of the DUT W is calculated for each DD.

[0029]

(Equation 8)

[0030] However, I ₀ is the exposure X-ray dose, I is transmitted X-rays, x is the measured object W thickness, density of mu _m is the mass absorption coefficient, [rho is the object W, M is divided transmission region DUT mass for each

According to an eleventh aspect of the present invention, in the X-ray mass measuring apparatus according to the ninth or tenth aspect, a foreign substance detecting unit for detecting foreign substances in the objects Wa to Wd from the transmission data y. It is characterized by having.

According to a twelfth aspect of the present invention, there is provided the X-ray mass measuring apparatus according to the eleventh aspect, wherein the mass calculating section includes at least one of the objects Wa to Wd in the foreign matter detecting section. When a foreign substance is detected in the divided transmission area, the masses of the objects Wa to Wd in at least the other divided transmission areas where the foreign substance is not detected are calculated.

According to a thirteenth aspect of the present invention, there is provided an X-ray mass measuring apparatus according to any one of the fifth to twelfth aspects, wherein the constituent elements of the object to be measured W correspond to each of the objects to be measured W. the object to be measured parameter storage unit 12 that is, the X-ray wavelength corresponding to the exposure of X-rays I ₀ with respect to the measured object W, the a composition element of the object W, is the mass absorption coefficient mu _m based on Mass absorption coefficient storage unit 13 stored
The parameter setting unit 10 calls up the corresponding composition element from the set DUT, and based on the composition element and the corresponding X-ray wavelength, the mass absorption coefficient storage unit 13 and wherein the deriving the mass absorption coefficient mu _m.

According to a fourteenth aspect of the present invention, there is provided an X-ray mass measuring apparatus according to any one of the fifth to twelfth aspects, wherein a plurality of types of constituent elements constituting the object to be measured W are measured. An object parameter storage unit 12 corresponding to each object W, an X-ray wavelength corresponding to an exposure X-ray dose I ₀ to the object W, and each composition element of the object W;
Wherein the mass absorption coefficient mu _m is mass stored absorption coefficient storage unit 13, comprising a based on the parameter setting unit 10, as well as calls the corresponding composition element from a set the object to be measured W, on the basis of the corresponding X-ray wavelength corresponding each composition element and the said mass from said absorption coefficient storage unit 13 corresponding to derive the mass absorption coefficient mu _m for each composition element, characterized by the averaging process .

In the X-ray mass measuring apparatus according to claim 7, the measurement parameter further includes the measured object W.
Only when no foreign matter is detected in the object to be measured W by the foreign matter detection unit, the density data ρ and the unit mass are calculated from the unit mass based on the above equation. A thickness measuring unit for measuring the thickness x of each unit transmission region, and a thickness for determining whether or not the measured thickness x of the unit transmission region of the device under test W is within a predetermined range. And a determining unit, wherein when the measured thickness x is determined to be within the predetermined range by the thickness determining unit, the total mass M of the measured object W is calculated. Is also good.

12. The X-ray mass measuring apparatus according to claim 11, wherein the measurement parameter further includes density data ρ of the object to be measured W, and the foreign matter detector detects the density of the object to be measured W. When a foreign substance is detected in at least one of the divided transmission areas, a thickness for measuring a thickness x per unit transmission area of the DUT W in at least another divided transmission area where the foreign substance is not detected. A measurement unit, comprising: a thickness determination unit that determines whether the measured thickness x of the unit transmission region of the device under test W is within a predetermined range, and the mass calculation unit includes: At least the mass M of the measured object W in the divided transmission region in which the measured thickness x is determined to be within the predetermined range by the thickness determination unit may be calculated.

As described above, the mass measurement and the thickness measurement of the measured object W can be simultaneously performed based on the transmitted X-ray dose of the same measured object W. In addition, since the quality can be selected before measuring the total mass (or the mass of each divided transmission region), it is not necessary to measure the mass of the defective product.

This makes it possible to shorten or speed up the processing time. Further, by adding the thickness measurement, it is possible to further improve the accuracy of the missing item inspection of the workpiece W.

[0039]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described. FIG. 1 is a perspective view showing the external appearance of the X-ray mass measurement device 1. The X-ray mass measuring apparatus 1 is provided in a part of a transport line, and detects the presence or absence of a foreign substance mixed into an object to be measured W (including the surface) sequentially transported at a predetermined interval. . The X-ray mass measuring device 1 includes a transport unit 2
, An X-ray generation unit 3 and an X-ray detection unit 4 are provided inside the apparatus main body, and a display unit 5 is provided on an upper front surface 1a of the apparatus main body.

The transporting unit 2 includes, for example, raw meat, fish, processed food,
It transports the object to be measured W of each kind, such as a medicine, and is constituted by, for example, a belt conveyor horizontally arranged with respect to the apparatus body. The transport unit 2 carries out the object to be measured W loaded from the carry-in port 2a to the carry-out port 2b at a predetermined transfer speed set in advance by driving the drive motor 6.

The X-ray generation unit 3 detects foreign matter in the conveyance path of the object W to be conveyed, and is provided above the belt conveyor 2 at a predetermined height. The X-ray detector 4 is provided inside the belt conveyor 2 so as to face the X-ray generator 3.

The X-ray generating section 3 has a configuration in which a cylindrical X-ray tube 8 provided inside a metal box 7 is immersed in insulating oil (not shown). Is irradiated on the anode target to generate X-rays. The X-ray tube 8 is provided such that its longitudinal direction Y is orthogonal to the transport direction X of the workpiece W. The X-rays generated by the X-ray tube 8 are emitted toward the lower X-ray detector 4 in a substantially triangular screen shape by a slit (not shown) along the longitudinal direction Y. .

The X-ray detector 4 detects X-rays transmitted through the object W when the object W is irradiated with the X-rays, and detects the transmitted amount of the detected X-rays. Output an electrical signal corresponding to.

Although not shown, the X-ray detector 4 includes a plurality of (for example, several hundreds) linearly arranged in a direction Y orthogonal to the transport direction X of the workpiece W transported on the belt conveyor 2, for example. ), And an array of line sensors including a photodiode and a scintillator provided on the photodiode. In the X-ray detection unit 4 having such a configuration, when X-rays are emitted from the X-ray generation unit 3 to the workpiece W, the transmitted X-rays transmitted through the workpiece W are scintillated. Receive and convert to light. Further, the light converted by the scintillator is received by a photodiode disposed below the scintillator. Each photodiode converts the received light into an electric signal. The electric signal has a level corresponding to the intensity of the received X-ray,
The X-ray detection unit 4 outputs this electric signal to the data processing unit.

FIG. 2 is a schematic block diagram showing the electrical configuration of the X-ray mass measuring apparatus 1. X-ray mass measurement device 1
1 includes a measurement parameter setting unit 10, a measurement parameter storage unit 11, a control unit 20 including a CPU 21, various memories 22, 23, and the like, and a display unit 5 for outputting calculation results, in addition to the configuration of FIG. It is schematically configured.

The measurement parameter setting section 10 is constituted by a push button or a touch panel, and sets each parameter used for mass measurement. The measurement parameter, a constituent element of the workpiece W, by the density [rho, the exposure X-ray dose I _0, the mass absorption coefficient mu _m, X-ray detection unit 4 which irradiates the workpiece W performance of the workpiece W The correction coefficient A and the like.

The measurement parameter storage unit 11 includes an object parameter storage unit 12, a mass absorption coefficient storage unit 13, a correction coefficient storage unit 14, an X-ray wavelength storage unit 15, and a setting parameter memory 16.

As shown in FIG. 3, the DUT parameter storage unit 12 is a data table in which composition elements are stored for each DUT W. In addition, when the composition element includes the DUT W composed of a plurality of types, the DUT parameter storage unit 12 as shown in FIG. 4 is used. The composition element subfield is a field in which all element symbols are arranged, and the composition element for each device under test W is selected by bit information in the data item of the composition element symbol. For example,
The object to be measured W (A) is a substance composed of the composition elements of H and Li.

When the operator selects and inputs an object W to be measured in the measurement parameter setting section 10, the CPU 21
The composition element of the DUT W selected from the DUT parameter storage unit 12 shown in FIG. 3 or FIG.

Although not shown, the X-ray wavelength storage unit 15 stores the exposure X-ray dose I inputted numerically by the measurement parameter setting unit 10.
₀ is a data table corresponding to the X-ray wavelength at that time. When the operator sets an exposure X-ray dose I ₀ numerically input by the measurement parameter setting unit 10, the corresponding X-ray The wavelength is called and stored in the setting parameter memory 16.

Although not shown, the correction coefficient storage unit 14 stores X
This is a data table corresponding to the number of lines of the line sensor constituting the line detection unit 4. When the operator selects and sets the model of the X-ray generation unit 3 provided in the apparatus main body by the measurement parameter setting unit 10, the CPU 21 , The corresponding correction coefficient A is called and stored in the setting parameter memory 16.

As shown in FIG. 5, the mass absorption coefficient storage unit 13 is a data table in which the vertical axis (column) includes compositional elements and the horizontal axis (row) includes X-ray wavelengths. This data table 13
Is a mass series coefficient table for various X-ray substances published in the scientific chronological table.

[0053] the data item at the intersection of each column and each row is stored in advance the mass absorption coefficient mu _m. And CPU
By a command from the 21, setting parameters X-ray wavelength and a constituent element stored in the memory 16 is called, with reference to the data table 13, the row and column directions and there is mass absorption coefficient mu _m crossed extracted Is done. The extracted mass absorption coefficient mu _m is stored in the set parameter memory 16.

The control section 20 is generally constituted by a CPU 21 for controlling the whole apparatus and executing various arithmetic processing, a program storage section 22 composed of a ROM or the like, and a data memory 23 composed of a RAM or the like. This control unit 20
Is functionally composed of a data processing unit, a transmitted X-ray dose calculation unit, and a mass calculation unit. These are execution programs stored in the program storage unit 22,
This is executed by the CPU 21.

The data processing section performs a predetermined number of lines (for example, 480 lines) from the X-ray detection section 4 by A / D conversion.
Is converted into transmission data y (i) for each unit transmission area (for example, 1 cm ² ) (where i = 1, 2, 2).
..., n. n is the number of unit areas). Each transmission data y is 0 to 2
It has 55 levels of transmission levels and coordinate values.
1 is stored in the data memory 23 in units of one device under test W.

The transmitted X-ray dose calculating section calculates the transmitted X-ray dose I for each transmitted data y (i) by multiplying each transmission data y stored in the data memory 23 by the correction coefficient A. Each transmitted X-ray dose data I is stored in the data memory 23 via the CPU 21 in units of one DUT W.

The mass calculating section calculates the total mass of the measured object W. The data used for the mass calculation are the measurement parameters and the transmitted X-ray dose data I set by the measurement parameter setting unit 10.

Before calculating the total mass of the object W, first, an equation for calculating the unit mass of each unit transmission region (unit area) of the object W is derived. The method of deriving this equation is as follows. The X-ray absorption coefficient of the measured object W is expressed as μ [1 / c
m], the exposure X-ray dose is I ₀ , the transmitted X-ray dose is I, and the measured object W
Is defined as x [cm], the following equation is established.

[0059]

(Equation 9)

The X-ray absorption coefficient μ [1 / cm] changes even if the same substance has a different density ρ [g / cm ³ ]. Therefore, the X-ray absorption coefficient μ [1 / cm] is changed to the density ρ [g / c
m ³ ] divided by the mass absorption coefficient μ _m (μm = μ / ρ) [cm
² / g]. Therefore, the above equation (1) becomes as follows.

[0061]

(Equation 10)

Here, since the transmitted X-ray dose I is the product y (i) A of the transmission data y (i) of each unit transmission area obtained from the X-ray generation unit 3 and the correction coefficient A, the above-mentioned (2) The expression is as follows.

[0063]

[Equation 11]

By transforming equation (3), the following equation is obtained.

[0065]

(Equation 12)

Here, the unit of the left side ρx of the equation (4) is:
[G / cm ³ ] × [cm] = [g / cm ² ], and the right side of equation (4) is the mass of a certain unit transmission region (unit area 1 cm ² ). By substituting the measurement parameters μ _m , I ₀ , A and the transmission data y (i) for each unit area into this equation (4), the unit mass for each unit transmission area is calculated.

Then, the integration is performed over the entire transmission region of the transmission X-ray transmitted through the object W. That is, the unit masses calculated for each unit transmission region are summed, and the total mass M of the DUT W is calculated by the following equation (5).

[0068]

(Equation 13)

The display section 5 is composed of a display or the like.
The calculation result in the control unit 20 is displayed and output so as to be visible.

Next, the operation of the present embodiment will be described. As shown in the flowchart of FIG.
T100), input processing (ST200), measurement processing (ST
300), arithmetic processing (ST400), output processing (ST5)
00).

The initialization (ST100) will be described. As shown in the flow of FIG. 7, when the operator presses the model selection button of the X-ray detection unit 4 in the measurement parameter setting unit 10, the model name is displayed on the display screen of the measurement parameter setting unit 10. Select the installed model (ST10
1) In response to a command from the CPU 21, the corresponding correction coefficient A is called (ST102) and stored in the setting parameter memory 16 (ST103).

Next, the process proceeds to an input process (ST200). In the input process, as shown in the flow of FIG. 8, the operator operates the measurement parameter setting unit 10 to
The exposure amount of X-rays I ₀ is set to numeric input to exposure to (S
T201). When the exposure X-ray dose I ₀ for exposure is set, C
In response to a command from the PU 21, the corresponding X-ray wavelength is called from the X-ray wavelength storage unit 15 (ST202).

Next, the operator sets the measurement parameter setting unit 1
When the DUT selection button is pressed at 0, the DUT name is displayed on the display screen of the measurement parameter setting unit 10. When an object W to be measured is selected and determined from these, the composition element of the selected object W is called from the object parameter storage unit 12 shown in FIG. ). Then, by referring to the data table of the mass absorption coefficient storage unit 13, the mass absorption coefficient mu _m to a constituent element and the X-ray wavelength intersect is extracted (S
T204). The set measurement parameters are stored in the set parameter memory 16 (ST205).

Next, the process proceeds to a measurement process (ST300). When the operator presses the measurement start button (ST30)
1) The conveyor 2 operates, and the workpiece W is transported between the X-ray generation unit 3 and the X-ray detection unit 4. Then, in response to a command from the CPU 21, the X-ray generation unit 3
X-rays of the set exposure X-ray dose I ₀ are emitted (ST30).
2).

The object to be measured W passes through a substantially triangular screen formed by exposure X-rays. The emitted X-rays pass through the object to be measured W that passes immediately below the X-ray generation unit 3. The transmitted X-ray is detected by the X-ray detector 4 as an electric signal (ST3).
03). The detected electric signal is converted by the data processing unit into transmission data y for each unit transmission area (ST3).
04).

Next, the processing shifts to an arithmetic processing (ST400). Conversion processing of transmission data y over all transmission areas (ST3
When 04) is completed, as shown in the flow shown in FIG. 10, the correction coefficient A, the mass absorption coefficient of the object W mu _m,
Calling a measurement parameter consisting of exposure X-ray dose I _0, the transmission data y (ST 401). These are substituted into the equation (4) to calculate a unit mass for each unit transmission region (ST4).
02). Then, based on the equation (5), integration over the entire transmission region is performed to calculate the total mass of the DUT W (ST4).
03). The calculation result is displayed on the display unit 5 (ST5).
00).

As described above, by using transmitted X-rays, it is possible to calculate the mass of the DUT W without providing any weighing device. Therefore, the mass of the DUT W can be easily measured. Another object of the present invention is to reduce the space or size of the entire device. This also eliminates the need for a mass measuring device, and can prevent an increase in cost.

In the above-described embodiment, the input processing (ST200) has been described using the DUT parameter storage unit 12 shown in FIG. 3. However, in the case of the DUT parameter storage unit 12 shown in FIG. As shown in FIG. 11, after setting the X-ray wavelength (ST202), if the operator selects the DUT by using the measurement parameter setting unit 10, C
The PU 21 stores the DUT parameter storage unit 12 shown in FIG.
, A plurality of constituent elements are extracted (ST21).
3). Then, reading the X-ray wavelength, for each composition element extracted, with reference to the mass absorption coefficient storage unit 13, extracts the mass absorption coefficient μ _m (ST214). Then, averaging the mass absorption coefficient mu _m for each extracted composition elements (ST215). Then, the measurement parameter memory, exposure of X-rays I _0, and stores the averaged mass absorption coefficient μ _m (ST216).

As a result, even in the object W composed of a plurality of composition elements, the optimum mass absorption coefficient μ for the object W is obtained.
_m can be calculated, and the accuracy of the mass measurement of the measured object W is improved.

Further, the DUT parameter storage unit 12 shown in FIG.
I decided to memorize a plurality of constituent elements,
As shown in the DUT parameter storage unit 12 shown in FIG.
Further, the bit information, by weighting corresponding to the amount of a constituent element constituting each object to be measured W, may calculate the weighted average of the mass absorption coefficient mu _m in ST215.

In this way, even if the amount of each of the constituent elements in the object W composed of a plurality of composition elements is different, weighting is performed in advance to further optimize the mass of the object W to be measured. it is possible to calculate the absorption coefficient mu _m,
The accuracy of the mass measurement of the workpiece W is further improved.

Next, the second X-ray mass measuring apparatus 1 of the present invention
An embodiment will be described. In this example, FIG.
As shown in (a), this is an example in which objects to be measured Wa to Wd of the same composition element are housed in respective housing portions 40a to 40d of a housing body 40 divided into a plurality (four in the figure).

In the present embodiment, the control unit 20 of the first embodiment is further provided with the divided transmission areas DA to D of the container 40.
This is a configuration in which a data extraction unit that extracts transparent data y for each D is functionally added. The data extraction unit preliminarily sets the opening areas (divided transmission areas DA to DD) of the storage units 40a to 40d.
Is stored as coordinate values. Then, the transmission data y of the measured objects Wa to Wd in the divided transmission areas DA to DD are
Masks MA to M for binary information shown in FIGS.
By superimposing D and taking a logical product, the transmission data y for each of the measured objects Wa to Wd is individually extracted.

Next, the operation of the present embodiment will be described. As in the first embodiment, initialization (ST100) and input processing (ST200) are performed, and measurement processing is performed from ST301 to ST304 as shown in FIG. ST304
When the transmission data y of all the objects to be measured Wa to Wd in the container 40 is obtained in the above, the divided transmission areas DA (DB, D
Only the coordinate values of C, DD) are “1” and the other areas are “0”.
A mask process is performed using a mask MA (MB, MC, MD) (shown in black in the figure), and the divided transmission areas DA (DB, DC,
Only the transmission data y of DD) is extracted (ST305).

Then, mass calculation processing (ST400) and output processing (ST500) are performed for each of the extracted transmission data y of each divided transmission area, as in the first embodiment. Thus, the objects Wa to Wd in the container 40 can be individually weighed, and the plurality of objects Wa to Wd can be simultaneously and efficiently measured in a short time.

In the above-described embodiment, the housing 4 having the housing portions 40a to 40d equally divided into four.
Although 0 is used and the divided transmission areas DA to DD corresponding to the storage sections 40a to 40d are applied, the number of storage sections is not limited to this as long as the object to be measured W can be stored. May be. In accordance with this, the divided transmission area is stored. Further, the sizes of the housing sections 40a to 40d do not need to be uniform, and may be changed according to the measured object.

Further, in the above-described embodiment, a plurality of objects to be measured are used. However, as shown in FIG. In this case, the container 40 is not used. Then, as shown in FIG. 15, the coordinate values of the transmission data y of the single device under test W composed of the respective parts Wa to Wd,
The mask processing may be performed using the masks MA to MD in correspondence with the coordinate values of the divided transmission areas DA to DD. Thereby, the mass distribution of the single DUT W can be detected.

Next, a third embodiment of the present invention will be described. In the present embodiment, the control unit 20 of the above-described first and second embodiments functionally includes a foreign object detection unit that detects the presence or absence of a foreign object in the measured object W (including the surface). Configuration. The foreign matter detection unit performs an inspection process for foreign matter mixed into the workpiece W based on the transmission data y.

Next, the operation of this embodiment will be described. As shown in the flow of FIG. 16, the foreign matter detection processing (ST600) is executed between the measurement processing (ST300) and the calculation processing (ST400).

This foreign object detection processing (ST600) is performed in FIG.
As shown in the flow of FIG. 7, based on the transmission data y corresponding to the transmission level of the X-ray transmitted through the object W, foreign matter such as metal, glass, stone, and bone is mixed into the object W. It is determined whether or not there is (ST601). When a state in which X-rays are not transmitted due to foreign matter occurs, that is, when the transmission level of the transmission data y based on the transmitted X-ray amount I is abnormally low,
It is determined that foreign matter is mixed (ST602-YES).

An NG process is performed on the device under test W based on the result of this determination. That is, a selection signal indicating that the device under test W is defective is output to the outside, and image data obtained by directly developing the input data into an image is displayed on the display unit 5 via an image processing unit (not shown).
(ST603). When it is determined that there is no foreign object (ST602-NO), the process proceeds to ST400.

In this embodiment, the provision of the foreign object detection enables the simultaneous execution of the foreign object detection and the mass measurement based on the same transmission data y. Also, according to the foreign matter detection result, the mass measurement process (ST400) is performed only when it is determined that there is no foreign matter, and the mass measurement of the measured object W determined to have foreign matter is not performed. Efficiency will be improved.

When applied to the second embodiment,
Since the mask processing is performed in ST305, the foreign substance detection processing (ST600) is performed for each of the divided transmission areas DA to DD, that is, for each of the measured objects Wa to Wd of the container 40. .

Next, a fourth embodiment of the present invention will be described. This embodiment is obtained by adding a function for measuring the thickness of the workpiece W to the third embodiment described above.

In the present embodiment, as shown in FIGS. 18 to 20, the density data ρ of each DUT W is stored in the DUT parameter storage unit 12 shown in FIG. 3, FIG. 4 or FIG. The data table 12 is used.

Further, the controller 20 measures the thickness x of each unit transmission area of the object W from the density data ρ and the transmission data y only when no foreign object is detected in the object W by the foreign object detector. This is a configuration functionally provided with a thickness measuring unit to be used.
Further, the thickness x of the unit transmission region of the measured object W is measured.
Are functionally provided with a thickness determination unit for determining whether or not the thickness is within a predetermined range.

The thickness measuring section measures the thickness x of the workpiece W for each transmission data y from each transmission data y stored in the data memory 23. The transmission data y is calculated based on the fourth equation. That is, the mass calculation unit calculates the unit mass of each unit transmission region on the right side of the equation (4). on the other hand,
The thickness data x for each unit transmission area is calculated by substituting the density data ρ extracted from the DUT parameter storage unit 12 shown in FIGS. 18 to 20 into the left side. The calculated thickness data x is stored in the data memory 23 via the CPU 21 in units of one measured object W.

In the thickness judging section, an upper threshold, a lower threshold, or both an upper threshold and a lower threshold of the thickness x of the workpiece W are set. If an upper threshold is set,
The effective range is less than the upper threshold. When the lower threshold is set, the effective range is equal to or higher than the lower threshold. When both the upper threshold and the lower threshold are set, the effective range is from the lower threshold to the upper threshold.

Further, the thickness judging section sets the outside of the effective range,
That is, the upper limit threshold of the number of thickness data x determined to be out of the specified thickness is set. Thereby, it is determined whether the measured object W is out of the specified thickness.

Next, the operation of this example will be described. The steps from the initial setting (ST100) to the measurement processing (ST300) and the foreign matter detection processing (ST600) are the same as those in the third embodiment, and therefore will not be described. As shown in the flow of FIG. 21, first, each transmission data y is derived in ST300, and then a measurement parameter including density data ρ and each transmission data y are read (ST401). Then, a unit mass calculation process is executed for each transmission data y (ST402).

Next, thickness data x is calculated for each unit transmission area from equation (4) (ST411). Then, the thickness determination is performed for each thickness data x. In the thickness determination, the thickness data x out of the effective range of the thickness of the workpiece W is counted. (ST412).

When it is determined that the count value is smaller than the set value (the upper limit threshold of the number of thickness data x) (ST41)
3-NO), the entire mass calculation process of the measured object W is executed (ST403). When it is determined that the count value is equal to or larger than the set value (ST413-YES), the entire mass measurement is not performed, and the object to be measured W is carried out from the carry-out port 2b, and ST60.
NG processing similar to that of No. 3 is performed (ST414).

In the third embodiment to which the second embodiment is applied, the mass of the object to be measured is calculated for each divided transmission area (ST403).

As described above, the mass measurement and the thickness measurement of the object W can be simultaneously performed based on the transmitted X-ray dose of the same object W. In addition, since the quality can be selected before the measurement of the total mass (or the mass of each divided transmission region), it is not necessary to measure the mass of the defective product. This makes it possible to reduce the processing time or increase the processing speed. Also, by adding thickness measurement,
Further, it is possible to improve the accuracy of the missing item inspection of the workpiece W.

[0105]

As described above, in the X-ray mass measuring apparatus according to the present invention, the mass of the object to be measured is calculated from a predetermined formula based on the amount of X-ray transmission of the object to be measured. It is possible to easily and simplify mass measurement. In particular, by performing mass measurement by software processing without providing a mass measuring device for the object to be measured, it is possible to achieve space saving or miniaturization of the entire apparatus. In addition, this eliminates the need for a mass measuring device, thereby making it possible to prevent an increase in cost.

Further, by dividing the transmission area of the object to be measured, mass measurement can be performed for each of the divided areas. This makes it possible to clarify the mass distribution of each divided region of the device under test.

Further, by deriving the measurement parameters for each object to be measured, it is possible to easily set the measurement parameters. This also makes it possible to further easily and simplify the measurement of the mass of the measured object.

Further, by combining the foreign matter detection by X-rays, it is possible to improve the accuracy of the inspection for the missing part of the measured object. In addition, it is possible to simultaneously perform the mass measurement and the thickness measurement of the measurement target W based on the transmitted X-ray dose of the same measurement target W. This makes it possible to shorten or speed up the processing time of foreign object detection and mass measurement on the same object to be measured. In particular, by performing foreign matter detection processing before mass measurement and determining the presence or absence of mass measurement based on the detection result, it is possible to further shorten or speed up the processing time.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an external appearance of an X-ray foreign matter detection device according to the present invention.

FIG. 2 is a block diagram showing an electrical configuration of the X-ray foreign matter detection device according to the present invention.

FIG. 3 is a diagram showing an example of an object parameter storage unit of the X-ray foreign matter detection device according to the present invention.

FIG. 4 is a diagram showing another example of the measured object parameter storage section of the X-ray foreign matter detection device according to the present invention.

FIG. 5 is a diagram showing a mass absorption coefficient storage unit of the X-ray foreign matter detection device according to the present invention.

FIG. 6 is an overall processing flowchart of the X-ray foreign matter detection device according to the present invention.

FIG. 7 is a flowchart of an initial setting of the X-ray foreign matter detection device according to the present invention.

FIG. 8 is a flowchart of an input process of the X-ray foreign matter detection device according to the present invention.

FIG. 9 is a flowchart of a measurement process of the X-ray foreign matter detection device according to the present invention.

FIG. 10 is a flowchart of a calculation process of the X-ray foreign matter detection device according to the present invention.

FIG. 11 is a flowchart of another input process of the X-ray foreign matter detection device according to the present invention.

FIG. 12 is a diagram showing another example of the measured object parameter storage unit of the X-ray foreign matter detection device according to the present invention.

FIG. 13 is a schematic view of mask processing of an X-ray foreign matter detection device according to the present invention (when there are a plurality of objects to be measured).

FIG. 14 is a flowchart of a measurement process including a mask process of the X-ray foreign matter detection device according to the present invention.

FIG. 15 is a schematic diagram of the X-ray foreign matter detection device mask processing (in the case of a single measured object) according to the present invention.

FIG. 16 is an overall processing flowchart including a foreign matter detection process of the X-ray foreign matter detection device according to the present invention.

FIG. 17 is a flowchart of a foreign substance detection process of the X-ray foreign substance detection device according to the present invention.

FIG. 18 is a diagram illustrating a modification of the device under test parameter storage unit illustrated in FIG. 3;

FIG. 19 is a diagram showing a modification of the device under test parameter storage section shown in FIG. 4;

20 is a diagram showing a modification of the device under test parameter storage section shown in FIG.

FIG. 21 is a flowchart of another calculation processing of the X-ray foreign matter detection device according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... X-ray mass measuring device, 3 ... X-ray generation part, 4 ... X-ray detection part 10 ... Measurement parameter setting part, 12 ... Measured object parameter storage part 13 ... Mass absorption coefficient storage part W, Wa-Wd ... measured, I ₀ ... exposure of X-rays, I ... transmitted X-rays x ... DUT thickness, mu _m ... mass absorption coefficient, [rho ... density M ... (total) mass of the object to be measured, da to dd ... Divided transmission area, y ... Transmission data

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2F067 AA27 AA58 AA62 EE10 FF00 HH04 JJ03 KK06 LL14 PP15 RR19 2G001 AA01 BA11 CA01 DA01 DA08 FA06 FA14 GA01 HA01 HA13 HA20 JA09 JA12 KA03 KA11 KA20 LA01 PA01 PA11

Claims (14)

[Claims] 1. An object to be measured (W) between an X-ray generator (3) and an X-ray detector (4) is irradiated with X-rays from the X-ray generator. The transmitted X-ray transmitted through the object is detected by the X-ray detection unit. Based on the detected transmitted X-ray dose (I), the mass of the object measured per unit transmission area is calculated from the following equation. Calculating, integrating the calculated unit mass per unit transmission region of the DUT over the entire transmission region of the transmitted X-ray to calculate the total mass (M) of the DUT. A mass measurement method using X-rays. (Equation 1) However, the density of I ₀ is exposure X-ray dose, I is transmitted X-rays, x is the measured object thickness, mu _m is the mass absorption coefficient, [rho is the object to be measured,
M is the total mass 2. An object to be measured (Wa to Wd) between an X-ray generator (3) and an X-ray detector (4) is irradiated with X-rays from the X-ray generator. The transmitted X-ray transmitted through the measured object is detected by the X-ray detection unit, and the mass of the measured object is determined for each unit transmission region based on the detected transmitted X-ray dose (I) as follows. The calculated unit mass of each of the unit transmission regions of the device under test is divided into a plurality of divided transmission regions (DA) obtained by dividing the entire transmission region of the transmission X-rays transmitted through the device under test. ~ D
A mass measurement method using X-rays, wherein the mass measurement is performed for each divided transmission region to calculate the total mass (M) of the DUT for each divided transmission region. (Equation 2) However, the density of I ₀ is exposure X-ray dose, I is transmitted X-rays, x is the measured object thickness, mu _m is the mass absorption coefficient, [rho is the object to be measured,
M is the total mass 3. The irradiation X for irradiating the object to be measured.
Setting a dose, selecting the object to be measured, extracting its constituent elements, and deriving the mass absorption coefficient based on the set exposure X-ray dose and the extracted constituent elements. The mass measuring method by X-ray according to claim 1 or 2, wherein: 4. The object to be measured is composed of a plurality of types of the composition elements, and sets the irradiation X-ray dose for irradiating the object to be measured, and selects the object to be measured. Extracting the plurality of types of composition elements, deriving and averaging mass absorption coefficients for each of the composition elements based on the set exposure X-rays and the extracted respective composition elements. The method for measuring mass by X-rays according to claim 1. 5. The mass absorption coefficient (μ) of at least an object to be measured.
_m ) and a measurement parameter setting unit (10) for setting a measurement parameter consisting of an exposure X-ray dose (I ₀ ) to the object to be measured; and an X-ray of the set exposure X-ray to the object to be measured. An X-ray generating unit (3) for irradiating an X-ray, an X-ray detecting unit (4) for detecting a transmitted X-ray transmitted through the object to be irradiated, and the transmission obtained from the X-ray detecting unit A data processing unit that derives transmission data (y) based on the X-ray; and a transmission X that calculates a transmission X-ray dose (I) from the transmission data.
X-ray mass measurement, comprising: a dose calculation unit; and a mass calculation unit that calculates an overall mass (M) of the measured object based on the set measurement parameters and the transmitted X-ray dose. apparatus. 6. The mass calculating unit calculates a unit mass of the object under measurement for each of the unit transmission areas according to the following equation, and calculates a unit mass over the entire transmission area of the transmitted X-rays transmitted through the object. 6. The X-ray mass measuring apparatus according to claim 5, wherein the total mass of the measured object is calculated by integration. (Equation 3) However, the density of I ₀ is exposure X-ray dose, I is transmitted X-rays, x is the measured object thickness, mu _m is the mass absorption coefficient, [rho is the object to be measured,
M is the total mass 7. The X-ray mass measurement apparatus according to claim 5, further comprising a foreign substance detection unit that detects a foreign substance in the object to be measured from the transmission data. 8. The mass calculating unit according to claim 7, wherein the mass calculating unit calculates the total mass of the measured object only when the foreign object is not detected in the measured object by the foreign object detecting unit. X-ray mass measurement device. 9. At least the mass absorption coefficient (μ
_m ) and a measurement parameter setting unit (10) for setting a measurement parameter consisting of an exposure X-ray dose (I ₀ ) to the object to be measured; and an X-ray of the set exposure X-ray to the object to be measured. An X-ray generating unit (3) for irradiating an X-ray, an X-ray detecting unit (4) for detecting a transmitted X-ray transmitted through the object to be irradiated, and the transmission obtained from the X-ray detecting unit A data processing unit that derives transmission data (y) based on X-rays; and a plurality of divided transmission regions (DA to DD) obtained by dividing all transmission regions of transmitted X-rays that have passed through the object to be measured. A data extraction unit for extracting the transmission data, and a transmission X for calculating a transmission X-ray dose (I) from the transmission data
A dose calculation unit; and a mass calculation unit that calculates a mass (M) of the measured object for each of the divided transmission regions based on the set measurement parameters and the transmitted X-ray dose. X-ray mass measurement device. 10. The mass calculator according to the following equation:
10. The mass of the DUT is calculated for each of the divided transmission regions by calculating a unit mass of the DUT for each of the unit transmission regions and integrating the unit mass of each of the divided transmission regions. An X-ray mass measurement apparatus as described in the above. (Equation 4) However, the density of I ₀ is exposure X-ray dose, I is transmitted X-rays, x is the measured object thickness, mu _m is the mass absorption coefficient, [rho is the object to be measured,
M is the mass of the DUT for each divided transmission area 11. The X-ray mass measurement apparatus according to claim 9, further comprising a foreign substance detection unit configured to detect a foreign substance in the measured object from the transmission data. 12. When the foreign matter detection unit detects foreign matter in at least one of the divided transmission areas of the object to be measured, the mass calculation unit performs another divided transmission in which at least the foreign matter is not detected. The X-ray mass measurement apparatus according to claim 11, wherein a mass of the object to be measured in a region is calculated. 13. An object parameter storage unit (12) in which a composition element of the object is associated with each of the objects.
A mass absorption coefficient storage unit (13) that stores the mass absorption coefficient based on an X-ray wavelength corresponding to an exposure X-ray dose to the measured object and a composition element of the measured object;
The parameter setting unit, while calling the corresponding composition element from the set DUT, based on the composition element and the corresponding X-ray wavelength, from the mass absorption coefficient storage unit the mass absorption The X-ray mass measurement apparatus according to claim 5, wherein a coefficient is derived. 14. An object parameter storage unit (12) in which a plurality of types of constituent elements constituting the object are associated with each of the objects, and an exposure X-ray dose corresponding to the object. A mass absorption coefficient storage unit that stores the mass absorption coefficient based on an X-ray wavelength and each constituent element of the object to be measured;
And the parameter setting unit calls the corresponding respective constituent elements from the set DUT, and based on the corresponding respective constituent elements and the corresponding X-ray wavelength, the mass absorption coefficient The X-ray mass measurement apparatus according to any one of claims 5 to 12, wherein the mass absorption coefficient is derived for each of the corresponding composition elements from a storage unit and averaged.