DE102017216671A1 - Exposure dose management device and exposure dose management method - Google Patents

Abstract

[Task] To provide technique of appropriate management of exposure dose for each component on a subject under investigation. [Means for Solving the Problem]

Description

[Technical area]

The present invention relates to an industrial X-ray examination apparatus, in particular, a technique for managing the exposure dose of electronic components by an X-ray examination.

[State of the art]

An industrial X-ray examination apparatus is generally known which irradiates examination subjects with X-rays and detects defects or defects of industrial products using transmission images or CT images. X-ray examination equipment of this type with the advantage that these difficult to detect from the outside places or the interior state of an object can be non-destructive, are applied to various types of investigations such. As investigations of bonding defects of a surface-mounted substrate, internal cracks of components, poor shape or a total inspection of electronic devices.

For industrial products, such as electronic devices, the drop in performance or failure may occur if the exposure dose exceeds an approval limit. It is therefore desirable that the manufacturer adequately apply the radiological dose, procedures, frequency etc. of the X-ray examination so that the exposure dose does not exceed the approval limit.

Among industrial products, it is particularly important to pay attention to electrical and electronic components (hereinafter simply "components"), since the components of several X-ray examination steps such. As a result, a large cumulative exposure dose to the end product may cause a disturbance, even if the exposure dose in the individual manufacturer or step falls below the regulatory limit.

Further, if the subject of the examination comprises several components (eg, a surface-mounted substrate, an electronic device and its module and component group loaded on the component shell), the exposure dose from the X-ray examination is not always the same for all components on the examination subject. Further, if X-rays are emitted several times in a single X-ray examination, it is also assumed that the X-ray irradiation frequency or the exposure dose varies depending on the components.

Consequently, methods for managing the exposure dose by X-ray depending on the components have heretofore been proposed. For example. Patent Literature 1 proposes an X-ray imaging device having a function of storing component data, irradiation data and allowable X-ray dose data for each component in the memory, obtaining a planned dose of the radiated X-rays from the component data and irradiation data, and exceeding the allowable ones Radiation dose is warned by the planned dose. In Patent Literature 2, there is further proposed a system for managing the X-ray exposure dose, which has a function of collecting an estimated exposure dose for each component in image acquisition and calculating a cumulative exposure dose of the subject substrate.

[Determined writings]

[Patent literature]

• [Patent Literature 1] JP Patent Laid-Open Publication No. 2002-350367
• [Patent Literature 2] JP Patent Laid-Open Publication No. 2012-163352

[Overview of the Invention]

[Problem to be Solved of the Invention]

Also, since X-rays are highly penetrating, the components disposed on the back side of the substrate are exposed to radiation (in the present specification, for convenience, the side of the subject of the radiation source side is "front side" or "first side" and the side facing away from the radiation source referred to as "backside" or "second side"). However, since the energy of X-rays penetrating through the components on the front side or the circuit board itself is partially absorbed and the X-rays are attenuated, the exposure dose of the components on the back side is smaller than that of the components on the front side. In addition, the attenuation of X-rays depends on the construction of the substrate, such. B. thickness or material of the circuit board or arrangement of components on the front. However, according to the prior art, the change of the exposure dose of the components on the back was never taken into consideration, so that it was difficult to accurately detect and manage the exposure dose for each component.

The present invention has been made in light of the above and is intended to provide a technique for adequately managing the exposure dose for each component on the subject matter.

[Means to solve the task]

In order to achieve the above purpose, the present invention uses the feature of calculating the exposure dose distribution of the object under investigation on the side of the radiation source and the radiation source on the opposite side.

Specifically, the present invention provides an exposure dose management apparatus comprising: an exposure dose determination unit for determining an exposure dose of an examination subject by an X-ray examination and an information output unit for outputting information regarding the exposure dose of the examination subject, the examination subject comprising a plurality of components, the exposure dose determining unit based on Position between a radiation source in the X-ray examination and the examination subject and the intensity of the radiated from the radiation source X-ray exposure dose distribution of the object under investigation on a first side, the radiation source side, and the exposure dose distribution of the object under investigation on a second side, which faces away from the radiation source, and based on the exposure dose distribution on the first and second Side and the arrangement of the respective several components, the exposure dose determined for each component.

According to this feature, the exposure dose for each component is determined on the basis of the exposure dose distribution of the examination subject on the radiation source side (first side) and the radiation source side (second side). It is therefore possible to determine the exposure dose of the components on both the first side and the second side with high precision. The present invention may therefore be advantageously applied to the management of exposure dose of a bilateral mounting substrate having a printed circuit board, components disposed on the first side of the printed circuit board, and components disposed on the second side of the printed circuit board.

The present invention can be used both for prediction of the exposure dose and for its recording. The prediction of the exposure dose is a processing for estimating the exposure dose that the subject of the examination will undergo during an X-ray examination, prior to the actual performance of the X-ray examination. The exposure dose recording is a processing for calculating the exposure dose of the examination subject after the actual X-ray examination.

It is preferable that the exposure dose detecting unit obtains the exposure dose distribution on the second side by considering the X-rays taken by the printed circuit board and / or the X-rays taken by the components arranged on the first side. By taking into account the absorption of X-rays by the printed circuit board or components on the first side, the intensity of the X-rays penetrating the second side, i. H. the exposure dose on the second page can be calculated with high precision.

It is preferred that if X-ray irradiations are performed a number of times in a single X-ray examination, the exposure dose determination unit determines the exposure dose by each X-ray irradiation, and the cumulative addition determines the exposure dose distribution in the individual X-ray examination. According to this feature, even with multiple X-rays, z. For example, if an examination subject is divided into multiple fields of view and examined, the exposure dose will be determined with high precision.

It is preferred that there is further provided: a judgment unit which, on the basis of the exposure dose determined by the exposure dose determination unit for each component, assesses whether the exposure dose is below an allowable amount. If z. If, for example, the exposure dose is predicted before the X-ray examination and a component is detected whose exposure dose exceeds the permissible level, it is possible to change the conditions of the X-ray radiation or cancel the X-ray examination.

It is preferred that there are further provided: an examination record storage unit which stores the record of the X-ray examination made in the past with respect to the examination subject, and an exposure dose update unit which calculates the exposure dose distribution and / or exposure dose for each component determined by the exposure dose determination unit cumulative exposure dose caused by previous X-ray examinations. This makes it possible, if the object of the examination undergoes multiple X-ray examinations, to record and manage the distribution of the cumulative exposure dose of the examination subject or the cumulative exposure dose for each component.

It is preferable that the information output unit outputs an exposure dose map showing the distribution of exposure dose to a display device. It is further preferable that the information outputting unit outputs information indicating the exposure dose for each component to the display device. It is further preferable that the information outputting unit outputs information for indicating whether the exposure dose for each component is below the allowable amount to the display device , By providing this information to the user, the detection and management of the exposure dose can be simplified for each component having the subject of interest.

The present invention may be further considered as an exposure dose management device having at least part of the above features. The present invention may be further considered as an X-ray examination system having an X-ray examination apparatus and an exposure dose management apparatus. The present invention may be further considered as an exposure dose management method or an X-ray examination method having at least a part of the above processings. The present invention may also be viewed as a program that causes the computer to perform respective steps of these methods, or as a computer-readable storage medium in which the program is not temporarily stored. The above respective features and processing may be combined to practice the present invention as long as there is no technical inconsistency.

[Effects of the Invention]

According to the present invention, the exposure dose for each component on the examination subject can be appropriately managed.

list of figures

• [ 1 ] 1 FIG. 12 is a diagram for a structure of an X-ray examination system according to a first embodiment. FIG.
• [ 2 ] 2 is a flow chart of the X-ray examination.
• [ 3 ] 3A is a plan view of the front of a substrate. 3B is a plan view of the back of the substrate.
• [ 4 ] 4 Fig. 10 is a diagram for an example of the conditions of X-ray irradiation.
• [ 5 ] Figs. 5A to 5C are illustrations of the X-ray irradiation condition according to FIG 4 following X-ray irradiation.
• [ 6 ] 6 FIG. 10 is a flowchart of an exposure dose determination processing according to the first embodiment. FIG.
• [ 7 ] 7 Fig. 12 is a diagram for an example of information of the X-ray source.
• [ 8th ] 8th FIG. 13 is a diagram for an example of item information. FIG.
• [ 9 ] 9A and 9B FIG. 10 are diagrams for a display example of the exposure dose map. FIG.
• [ 10 ] 10 FIG. 13 is a diagram for a display example of the table form of the exposure dose and the judgment result of the components. FIG.
• [ 11 ] 11A and 11B FIG. 11 are diagrams for a display example in the form of an arrangement image of the exposure dose and the judgment result of the components.
• [ 12 ] 12 FIG. 12 is an illustration of a structure of an X-ray examination system according to a second embodiment. FIG.
• [ 13 ] 13 FIG. 10 is a flowchart of an exposure dose determination processing according to the second embodiment. FIG.

Embodiment of the Invention

Hereinafter, an expedient embodiment of the present invention will be explained with reference to the drawings. The explanation of the respective features explained below is dependent on the structure of the apparatus to which the invention is applied or on various circumstances to change circumstances, so that the scope of the present invention is not limited to the following features.

<First Embodiment>

(X-ray examination system)

1 FIG. 15 is a diagram schematically showing a structure of an X-ray examination system according to a first embodiment. FIG.

The X-ray examination system 1 essentially comprises an X-ray examination device 10 and an exposure dose management device 11 on. The X-ray examination device 10 is a device for non-destructive examination of the object under investigation 12 using X-rays. According to the present embodiment, a mounting substrate having a plurality of assembled components is a subject of examination, and an apparatus for X-ray examination of the substrate, which examines a solder joint of each component, is given as an example. The exposure dose management device 11 is a device for managing the dose of exposure that is the subject of the study 12 obtained during an X-ray examination. The X-ray examination device 10 and the exposure dose management device 11 can be made in one piece or separately.

(X-ray examination apparatus)

The X-ray examination device 10 has an X-ray source 100 , an x-ray detector 101 , an edition 102 , a control unit 103 , an examination unit 104 , a storage unit 105 u. Like. On. The X-ray source 100 is a means of irradiating the subject matter 12 with X-rays and consists, for example, of a conical or fan-shaped X-ray generator. The x-ray detector 101 is an image pickup means for detecting the subject of the investigation 12 penetrate X-rays and output data of an X-ray transmission image, and consists of, for example, a scintillator and a two-dimensional CMOS (complementary-metal oxide semiconductor) sensor. The edition 102 is a means for holding and conveying the object of investigation 12 and serves the field of view of one of the X-ray source 100 and the X-ray detector 101 existing imaging system and the area to be examined on the examination subject 12 to position. When shifting the field of view of the image recording system, both the support 102 , as well as the image recording system or the two of the edition 102 and the image pickup system.

The control unit 103 is a unit for controlling the operations (shifting of the field of vision, X-ray irradiation, recording of the X-ray transmission image, examination processing in the examination unit 104 , Cooperation and data transmission with an external device, etc.) of respective units of the X-ray examination apparatus 10 , The examination unit 104 is a unit for examining the object of investigation 12 using one of the X-ray examination apparatus 10 obtained X-ray transmission image. Here are the functions of the control unit 103 and the examination unit 104 both through software processing using a computer with CPU ( Central processing unit (processor) and memory, as well as by circuits such as FPGA or ASIC realized.

The storage unit 105 is a unit for storing data such as configuration file of the X-ray examination apparatus 10 , Examination program, X-ray transmission image or examination result. The configuration file is the data in which the object of investigation 12 independent common information (such as initialization values, X-ray source specification 100 and the X-ray detector 101 etc.). The examination program is the data for defining steps of the X-ray examination and is used for each type of examination object 12 created and saved in advance. It is preferred that the examination program has definitions such as information of the examination subject 12 (such as the size, thickness, material of the substrate, position on the substrate, size and exposure dose of each component), condition of x-irradiation (such as irradiation position (face position), distance between the x-ray source and the substrate, Tube voltage, tube current, irradiation time and the like) as well as examination logic (such as characteristic obtained from the image, evaluation criterion of the examination (threshold value, value range), the judgment result corresponding processing). The storage unit 105 consists of a non-volatile storage device such. A flash memory or a hard disk.

(Operation of X-ray examination)

With reference to the flowchart according to 2 becomes an example of the operation of the X-ray examination by the X-ray examination apparatus 10 explained.

The control unit 103 first reads the configuration file from the storage unit 105 and takes the initialization of the X-ray examination device 10 before (step S20). Next, the control unit reads 103 the examination program, that of the type (such as article number of the substrate) of the examination subject 12 corresponds to, from the storage unit 105 (Step S21). The type of object of investigation 12 can be entered by the user as well as by reading a bar code, 2D code, IC tag or number printed on the substrate, or from an external device (such as a parent system managing the production line) be communicated.

From the control unit 103 a shift of the visual field of the image recording system, X-ray irradiation and recording of a transmission image is performed after the X-ray irradiation conditions defined in the examination program (steps S22-S24). When a plurality of X-ray irradiation conditions are set in the inspection program, the X-irradiation conditions are alternately changed to repeatedly perform the processings of steps S22-S24 (step S26).

In 3A and 3B is an example of a surface mount substrate as the subject of investigation 12 shown. 3A is a plan view of the front of the substrate, on the five components 31 - 35 are arranged. 3B is a top view (one of the in 3A the same direction seen perspective drawing) of the back of the substrate, on the two components 36 and 37 are arranged. 4 FIG. 12 shows an example of the X-ray irradiation condition prescribed in the examination program of the substrate. In 4 For example, there is shown an example in which X-irradiation is performed three times while changing the condition of the irradiation position (face position) of X-rays, the distance between the X-ray source and the substrate, the tube voltage, and the tube current. The unit "uA" of the tube current is here a brief representation of microamps. In 5A - 5C is one according to the X-ray irradiation conditions 4 following X-ray irradiation shown schematically. The left side of each drawing is the side view and the right side is the top view, with hatching showing the irradiation range of X-ray irradiation. Through this operation, X-ray transmission images with respect to three visual fields with the numbers 1 - 3 receive.

Subsequently, by the examination unit 104 after the examination logic defined in the examination program, extracts a required characteristic from the X-ray transmission images and judges whether the solder connection of the components on the substrate is good by comparing the values of the characteristic with the judgment criterion (step S26). The examination result of the examination unit 104 is output to the display device or an external device (step S27).

(With regard to exposure by X-ray examination)

As previously described, there is a risk that exceeding an allowable amount by the exposure dose of the component will cause degradation or failure. Since a single component often over several X-ray examination steps, such. For example, if the component manufacturer, the equipment manufacturer or the end-product manufacturer is carrying out tests, it is desired that not only the single-exposure dose but also a final cumulative exposure dose be readily recorded. According to the X-ray examination system 1 In the present embodiment, the exposure dose management device is used 11 the prediction, recording and output of the exposure dose made to each component 31 - 37 on the examination subject 12 in an X-ray examination of the X-ray examination apparatus 10 receive. The "prediction" is a pre-X-ray examination to estimate the exposure dose of the subject under investigation 12 , This prediction result can be z. For example, to confirm whether the X-ray irradiation condition is appropriate, or to assess whether the X-ray examination of the subject of the examination 12 can be used. The "record" is a processing for calculating the dose of exposure that is the subject of the study 12 in the X-ray examination actually receives, and to save them as a log. The stored log data becomes evidence for proving the exposure dose of the subject 12 in the following steps, manufacturer as supplier, consumers u. Like. Revealed.

Here it is preferred that in the prediction and recording of exposure dose by the X-ray examination with respect to the subject of the investigation 12 with several components such as a surface mounting substrate, the following points are considered.

• (1) In a single X-ray examination, X-ray irradiation is usually performed several times while changing the X-ray irradiation condition. In this case, the frequency of exposure (frequency of X-ray exposure) and the exposure dose may differ depending on the component. For example. in the examples according to 5A to 5C is the exposure frequency of the component 31 one and the component 34 in contrast, two. Consequently, it is necessary to calculate the exposure dose for each X-ray for each component and to determine the total amount.
• (2) The radiation dose in the irradiation area is not constant. Since the intensity of X-rays is inversely proportional to the square of the propagation distance, in the case of a general cone-shaped X-ray source, the average radiation dose in the irradiation area is maximum, and the radiation dose is reduced towards the end. The distribution of the radiation dose in the irradiation area can be calculated when the specification of the X-ray source 100 (Irradiation angle (propagation angle), etc.), a geometrical positional relationship between the X-ray source 100 and the object of investigation 12 , the irradiation conditions (tube voltage, tube current, irradiation time, etc.) of the X-ray source 100 out.
• (3) Since X-rays are strongly penetrating, the components (components 36 . 37 in 5A ) exposed to the radiation. However, since the energy of X-rays penetrating through the components on the front side or the circuit board is partially absorbed and the X-rays are attenuated, the exposure dose of the components on the back side is smaller than that of the components on the front side. In addition, the attenuation of X-rays depends on the construction of the substrate, such. Thickness or material of the printed circuit board or arrangement of the components on the front side (for example, if the X-rays penetrate a glass epoxy substrate having a thickness of 1 mm, the exposure dose will be reduced by about 60%.). Consequently, the exposure dose of the components on the back should be calculated taking into account the attenuation of the X-rays by the circuit board itself or components on the front.
• ( 4 ) It is possible that the permissible exposure dose varies depending on the type of component. Consequently, it is preferable to manage the exposure dose and allowable amount depending on the component.

(Exposure dose management device)

With reference to 1 becomes the construction of the exposure dose management device 11 explained. The exposure dose management device 11 has as its function the data entry unit 110 , the exposure dose determination unit 111 , the assessment unit 112 and the information output unit 113 on. The data input unit 110 is a means of obtaining various data used to determine the exposure dose. The exposure dose determination unit 111 is a means of determining the dose of exposure that the subject of the examination is obtained by an X-ray examination. The judging unit 112 is a means of assessing for each component whether the exposure dose is below an allowable amount. The information output unit 113 is a means for outputting information regarding the exposure dose of the examination subject to the display device 114 or an external device (not shown).

The exposure dose management device 11 may consist of a general purpose computer, the z. To the CPU (processor), a memory, a storage device (such as a hard disk), an input device (such as a keyboard, mouse, touch screen), a display device 114 , a communication interface u. Like. Is provided. In this case, the exposure dose management device 11 can be designed from a single computer or realized by cooperation of several computers, for example, the technology of distributed computing or cloud computing can be used. The respective functions of the exposure dose management device 11 According to the present embodiment, implementation of a required program can be realized by CPU. The functions can also be partially or completely from circuits such. B. ASIC (application specific integrated circuit) or FPGA (field programmable gate array) are designed.

(Determination of exposure dose)

With reference to flowchart according to 6 Fig. 10 is an example of processing for determining exposure dose by the exposure dose management device 11 explained. Here, in the assumption that an in 3A and 3B shown bilateral substrate taken as an example and according to the X-ray irradiation conditions according to 4 the following x-ray examination is carried out, the exposure dose of the several components 31 - 37 predicted on the substrate.

First, the data input unit receives 110 the data required to determine exposure dose (step S60). The data required to determine exposure dose are, for example: X-ray irradiation conditions are the information for calculating the irradiation position and intensity of X-rays and include, as an example in FIG 4 shown, preferably, the irradiation position, removal of the X-ray source 100 , Tube voltage, tube current, irradiation time, etc. The information of the X-ray source is the information for calculating the shape, size and intensity distribution of the X-ray irradiation area. In the case of a cone-shaped or fan-shaped X-ray source 100 will, as an example in 7 is shown, preferably, the irradiation angle (propagation angle) of rays obtained as information of the X-ray source. The item information is the information regarding the subject of the investigation 12 the X-ray examination. An example of the item information regarding in 3A and 3B shown bilateral substrate is in 8th shown. Here, as the information regarding the circuit board, the size, thickness, material of the substrate, and as component information, the numbers of the components, front / back of the substrate, position on the substrate, size, allowable exposure dose, and the like. from the subject information. The irradiation conditions described above, information of the X-ray source and the item information may be from the examination program and / or from the configuration file of the X-ray examination apparatus 10 to be obtained. This information, which is in 1 from the storage unit 105 the X-ray examination apparatus 10 can be obtained from other devices (such as a parent system of the X-ray examination device 10 , Memory for storing data) are also obtained.

Next, the exposure dose determination unit determines 111 based on the information of the X-ray source and X-irradiation conditions obtained in step S60, the exposure dose map of the front side (radiation source side) of the substrate (step S61). The exposure dose map is the exposure dose data depending on the position on the substrate and is recorded, for example, in the form of two-dimensional image data. The intensity of X-rays is inversely proportional to the square of the distance from the X-ray source 100 , proportional to the square of the tube voltage and proportional to the tube current and irradiation time. Thus, the value of the exposure dose for each position on the substrate may be based on the positional relationship between the X-ray source 100 and the substrate and the intensity of the X-ray source 100 radiated X-rays are determined. Here, the exposure dose can be determined both by a theoretical calculation alone, as well as by adding a correction corresponding to the difference of the irradiation conditions to the actual value measured in advance under predetermined conditions. As an example of the latter can be a method for the determination of Exposure dose at a tube current of 110 μA in the following formula, if the actual value is known at a tube current of 100 μA:

Exposure dose at a tube current of 110 μA = Actual value at a tube current of 100 μA × correction factor 1 ,1

If multiple X-rays are taken in a single X-ray, d. H. If conditions from a plurality of fields of view are encompassed by the X-ray irradiation conditions, exposure dose maps are determined from the respective X-ray exposures and assembled (cumulatively added) to produce a final exposure dose map.

Next, the exposure dose determination unit determines 111 based on the exposure dose map of the front side calculated in step S61 and the subject information, an exposure dose map of the back side (a radiation source opposite side) of the substrate (step S62). Specifically, the exposure dose determination unit determines 111 based on the thickness and the material of the substrate, a radiation dose received by the substrate and on the basis of the arrangement of components on the front side of a received from the components on the front side radiation dose. The exposure dose determination unit 111 Further, from the value of the exposure dose of the front side calculated in step S61, subtracts the radiation dose received from the substrate and the radiation dose taken by the components on the front side to obtain the value of the exposure dose of the back surface of the substrate.

The radiation dose received by the substrate can also be estimated on the basis both of a pre-measured actual value and of an actual X-ray photograph of locations where the components are not located on the substrate. With regard to the absorbed radiation dose of the individual component, both a standard value (fixed value) can be used uniformly and also be changed according to the component type or size (height) of the component (eg a recorded radiation dose for each component type can be obtained from the database) or from the result of an actual X-ray of sites where the components are on the substrate.

Next, with respect to all the components on the substrate, the processings in S63-65 are repeated (step S66). Hereinafter, a component as a processing object will be referred to as a notice member.

In step S63, the exposure dose determination unit determines 111 the exposure dose of the attention component. Specifically, the exposure dose determination unit determines 111 using an exposure dose map of the side (front or back) on which the attention item is located, a representative value of the exposure dose in the area occupied by the attention component, and considering this value as the exposure dose of the attention component. The representative value is a total value, average value, maximum value, intermediate value u. Like. Available. It is also possible to use the multiple values of these (eg, two values such as average value and maximum value) as the index of the exposure dose of the attention component.

In step S64, the exposure dose detection unit obtains 111 the permissible exposure dose of the attention component from the item information (s. 8th ). However, the method for obtaining the allowable exposure dose is not limited to this. For example. it is possible to uniformly apply a standard value (fixed value) to all the components, to obtain the permissible exposure dose for each type of component from the database, or based on the information entered as item information, e.g. B. type, material, size of the component to determine the permissible exposure dose.

In step S65, the judgment unit compares 112 the exposure dose of the attention component determined in step S63 with the admissible exposure dose of the attention component determined in step S64 in order to assess whether the exposure dose of the attention component is below the permissible exposure dose.

When the processing of the last component is finished (step S66; YES), the information output unit gives 113 the exposure dose map of the front and back of the substrate, the exposure dose of the respective components, the judgment result, and the like. to the display device 114 from (step S67).

In 9A is a display example of the exposure dose map of the front side of the substrate and in FIG 9B a display example of the exposure dose map of the back of the substrate is shown. In this example, the magnitude of the exposure dose is shown with a shading gradation, with a decreasing exposure dose approaching white and an increasing exposure dose approaching black. With the rectangular frame, the arrangement of the respective components on the front and the back is also shown. With the help of this exposure dose map can The distribution of the respective exposure dose of the front and the back of the substrate and the size of the exposure dose of each component are intuitively reproduced. In particular, a point at which the exposure dose accumulates through a plurality of X-ray irradiations can be easily distinguished. By displaying an exposure dose map as in 9B Further, the exposure dose of components on the back side of the substrate can be accurately detected, taking into account a received radiation dose of the substrate or the components on the front side. Further, the method of displaying the exposure dose map is not limited to this example, and each method is available. For example. It is possible to display the size of the exposure dose with a wrong color (also called a heat map) or to display it with a contour diagram. It is also possible to overlay the exposure dose map (computer graphics) over the image of the substrate.

In 10 an example is shown in which the exposure dose and the judgment result of each component are displayed in a tabular form. For each component, the number of the component, front and back of the substrate, exposure dose and the result of the evaluation are shown. With regard to the component whose exposure dose exceeds an allowable amount, the user can be notified of an alarm by marking such as blinking or highlighting.

11A and 11B is an example for displaying the exposure dose and the judgment result of each component in the form of an arrangement image. On the front and the back of the substrate, rectangles for respective components are shown, in which the exposure dose is shown. The color (or shade) of the rectangle of the component represents the size of the exposure dose. With regard to a component whose exposure dose exceeds an allowable amount, the user may be notified of an alarm by marking such as blinking or highlighting. It is also possible, the two of 10 as well as the 11A and 11B to display detailed information of the component in question or the corresponding row of the table according to 10 automatically display with highlight, if the user the rectangle of the component according to 11A or 11B determined (eg clicks).

Advantages of the Present Embodiment

According to the above construction of the present embodiment, the exposure dose of each component is determined based on the distribution of exposure dose of the examination subject on the front side (radiation source side) and the back side (one side away from the radiation source), so that the exposure dose of the components on both the front side, as well as on the back can be determined high-precision. Further, since X-ray pickup is taken into account by the printed circuit board or components on the front side, the exposure dose of the components on the back side can be determined with high precision. Consequently, the device according to the present embodiment can be applied particularly not only to the exposure dose management of a one-sided mounting substrate on one side of which components are mounted, but also of a two-sided mounting substrate on both sides of which components are mounted.

Further, according to the present embodiment, the respective exposure dose maps of the front and the back of the examination subject, the exposure dose of each component and the judgment result of whether the exposure dose of each component corresponds to an allowable dose are output to the display device. By providing this information to the user, the detection and management of exposure dose of each component is simplified by an X-ray examination.

<Second Embodiment>

With reference to 12 and 13 An X-ray examination system according to a second embodiment of the present invention will be explained. 12 FIG. 14 is an illustration for the structure of the X-ray examination system according to the second embodiment; and FIG 13 FIG. 10 is a flowchart of an exposure dose determination processing according to the second embodiment. FIG. While in the first embodiment described above, the exposure dose is determined by a single X-ray examination, in the second embodiment, a cumulative exposure dose is determined by multiple X-ray examinations in reference to the record of X-ray examinations made for a same subject in the past. Hereinafter, only a construction and processing proper to the second embodiment will be explained, and the explanation will be omitted with regard to a structure and processing similar to those of the first embodiment.

As in 12 shown is the exposure dose management device 11 according to the present embodiment, in addition to the functional structure according to the first embodiment also with the examination record storage unit 115 and the exposure dose update unit 116 Mistake. The examination record storage unit 115 is the database for storing the examination record for each examination subject (substrate in the present embodiment). The examination record is the information relating to the record of the X-ray examinations made in the past with respect to the examination subject. Any information is available as long as it can be used to determine the cumulative exposure dose of the subject of the study, for example, the frequency of the examination in the past or the exposure dose from past examinations, etc., can be used as an examination record. The exposure dose update unit 116 is a means of cumulating the exposure dose by past X-ray examinations to that of the exposure dose detection unit 111 determined exposure dose based on the examination record.

With reference to the flowchart according to 13 An exposure dose detection processing according to the present embodiment will be explained. In the flowchart according to 13 are also processing steps similar to those of the first embodiment ( 6 ), labeled with the same step numbers and their further explanation is omitted.

First, the data input unit receives 110 the data required to determine exposure dose (step S60). Next determined is the exposure dose determination unit 111 On the basis of the information of the X-ray source and X-irradiation conditions obtained in step S60, an exposure dose map of the front side (radiation source side) of the substrate (step S61). Based on the exposure dose map of the obverse calculated in step S61 and the subject information, the exposure dose determination unit determines 111 Further, an exposure dose map of the back side (a side facing away from the radiation source) of the substrate (step S62). The previous processes are the same as in the first embodiment.

Next receives the exposure dose update unit 116 an ID of the object of inspection via the data input unit 110 (Step S130). The ID (identification number) of the examination subject may be entered by the user as well as identified by reading a bar code, 2D code, IC tag or number printed on the substrate, or from an external device (such as a barcode). a parent system managing the production line).

Next receives the exposure dose update unit 116 from the examination record storage unit 115 an examination record corresponding to the ID of the examination subject (step S131). The examination record is made according to the present embodiment by the examination record storage unit provided in the apparatus 115 receive. However, this can also be obtained from an external database, an X-ray examination device or a higher-level system.

Next updates the exposure dose update unit 116 based on the examination record of the examination subject, respectively, the exposure dose of the front side and the back side determined in steps S61 and S62 (step S132). If z. For example, if the study frequency is available in the past as a study record, a cumulative exposure dose using the current exposure dose (the exposure dose calculated in steps S61 and S62) and the study frequency in the past can be calculated as follows: $$\begin{array}{l}\text{cumulative exposure dose}=\text{this time exposure dose x}\\ \left(\text{Examination frequency in the past}+1\right)\end{array}$$

If the exposure dose is available in the past as an examination record, a cumulative exposure dose can be calculated as follows: $$\begin{array}{l}\text{cumulative exposure dose}=\text{this time exposure dose x}+\text{past}\\ \text{exposure dose}\end{array}$$

The update method given here is an example, so that the cumulative exposure dose can also be determined by other calculation methods.

Through the above processings, the respective cumulative exposure dose maps of the front and the back are obtained. The following processings (steps S63-S67) are the same as those of the first embodiment, except for the use of the cumulative exposure dose map instead of the exposure dose map.

Advantages of the Present Embodiment

According to the above-mentioned construction of the present embodiment, in addition to the advantage according to the first embodiment, there is an advantage that, when subjecting the examination subject to multiple X-ray examinations, the distribution of the cumulative exposure dose of the examination subject or the cumulative exposure dose for each component can be detected and managed.

<Other Embodiment>

The structure according to the above-mentioned embodiments is a mere concrete example. The scope of the present invention is not limited to the above embodiments, and various modifications are possible within the scope of the technical idea.

In the above embodiments, for. B. as an object of investigation, the example of a two-sided mounting substrate listed. However, the present invention can also be applied to the investigation (shell inspection) of a component group loaded on a component shell. In the above-mentioned embodiments, the example in which only the front side is irradiated with X-rays was further shown. However, the present invention can also be applied to a study in which X-rays are emitted from both the front and the back. In this case, the above-mentioned exposure dose determination processing can be performed with respect to the two cases, ie, front-side irradiation and back-side irradiation, and these are aggregated together to obtain a cumulative exposure dose.

LIST OF REFERENCE NUMBERS

1: X-ray examination system, 10: X-ray examination device, 11: Exposure dose management device, 12: Examination object, 31 to 37: Components; 100: X-ray source, 101: X-ray detector, 102: support, 103: control unit, 104: examination unit, 105: storage unit, 110: data input unit, 111: exposure dose detection unit, 112: evaluation unit, 113: information output unit, 114: display device, 115: examination record storage unit, 116: exposure dose update unit

Claims (13)

An exposure dose management device (11), comprising: an exposure dose determination unit (111) for determining an exposure dose of an examination subject (12) from an X-ray examination and an information output unit (113) for outputting information regarding the exposure dose of the examination subject (12), characterized in that the Subject of examination (12) comprises a plurality of components (31, 32, 33, 34, 35, 36, 37), the exposure dose determination unit (111) based on the position between a radiation source (100) in the X-ray examination and the examination subject (12) and the intensity the X-rays radiated from the radiation source (100) determine and display the exposure dose distribution of the examination subject (12) on a first side, which is radiation source side, and the exposure dose distribution of the examination subject (12) on a second side, which faces away from the radiation source Based on the exposure dose distribution on the first and second sides and the arrangement of the respective plurality of components (31, 32, 33, 34, 35, 36, 37) determines the exposure dose for each component. Exposure Dose Management Device (11) Claim 1 , characterized in that the object to be inspected (12) comprises a mounting substrate on both sides, which comprises a printed circuit board, components (31, 32, 33, 34, 35, 36, 37) arranged on the first side of the printed circuit board and on the second side of the printed circuit board Components (31, 32, 33, 34, 35, 36, 37). Exposure Dose Management Device (11) Claim 2 characterized in that the exposure dose determination unit (111) determines the exposure dose distribution on the second side taking into account the acquisition of X-rays by the circuit board. Exposure Dose Management Device (11) Claim 2 or 3 characterized in that the exposure dose detection unit (111) determines the exposure dose distribution on the second side taking into account the acquisition of X-rays by the components disposed on the first side. Exposure dose management device (11) according to one of Claims 1 to 4 , characterized in that, when multiple X-ray exposures are made in a single X-ray examination, the Exposure Dose Determination Unit (111) Exposure Dose is determined by respective X-ray exposures and cumulatively added to determine an Exposure Dose Distribution by a single X-ray examination. Exposure dose management device (11) according to one of Claims 1 to 5 characterized in that a judging unit (112) is further provided for each component (31, 32, 33, 34, 35, 36, 37) on the basis of the exposure dose for each member (31, 32, 33, 34, 35, 36, 37) determined by the exposure dose determining unit (111). 32, 33, 34, 35, 36, 37) judges whether the exposure dose is below an allowable amount. Exposure dose management device (11) according to one of Claims 1 to 6 characterized in that an examination record storage unit (115) storing the record of the X-ray examination made in the past with the examination subject (12) and an exposure dose update unit (116) based on the record are determined by the exposure dose determination unit Exposure dose distribution and / or exposure dose for each component (31, 32, 33, 34, 35, 36, 37) Exposure dose cumulative through a previous X-ray examination. Exposure dose management device (11) according to one of Claims 1 to 7 characterized in that the information output unit (113) outputs an exposure dose map for displaying an exposure dose distribution to a display device (114). Exposure dose management device (11) according to one of Claims 1 to 8th characterized in that the information output unit (113) outputs information for showing exposure dose for each component (31, 32, 33, 34, 35, 36, 37) to a display device (114). Exposure dose management device (11) according to one of Claims 1 to 9 characterized in that the information output unit (113) outputs information to show whether the exposure dose for each component is below an allowable amount to a display device (114). An X-ray examination system (1), comprising: an X-ray examination apparatus (10) for performing an X-ray examination of an examination subject (12) and an exposure dose management apparatus (11) according to any one of Claims 1 to 10 which outputs information regarding the exposure dose of the subject under examination (12) by the X-ray examination. Exposure dose management method comprising an exposure dose determination step for determining exposure dose of an examination subject (12) by an X-ray examination and an information output step for outputting information regarding exposure dose of the examination subject (12), characterized in that the examination subject (12) comprises a plurality of components (31, 32, 33, 34, 35, 36, 37), and the exposure dose determination step comprises: a step of determining, based on the location between a radiation source (100) in the X-ray examination and the examination subject (12) and the intensity of the radiation source (100) radiated X-rays, the exposure dose distribution of the examination subject on a first side, the radiation source side, and the exposure dose distribution of the examination subject on a second side, which is remote from the radiation source is determined, and a Step in which the exposure dose for each component (31, 32, 33, 34) is calculated on the basis of the exposure dose distribution on the first and the second side and the arrangement of the respective several components (31, 32, 33, 34, 35, 36, 37) , 35, 36, 37) is determined. Program, the computer respective steps of an exposure dose management method according to Claim 12 caused causes.

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