JP2696471B2 - Board soldering condition inspection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to board soldering for irradiating a printed circuit board as an object to be inspected with X-rays, photographing a transmitted X-ray image thereof, and inspecting a soldering state of electronic components to the printed board. With respect to the condition inspection device, particularly, it is possible to easily align the inspection site of the printed circuit board with respect to the X-ray imaging range, and to remove distortion of the X-ray inspection image.
Prevents deterioration of image quality due to aging of X-ray imaging unit
The present invention relates to an apparatus for inspecting a soldering condition of a substrate.

[0002]

2. Description of the Related Art Recently, a technique using X-rays for inspecting a soldering state when an electronic component such as an IC (integrated circuit) is mounted on a printed circuit board has been developed. This is because, in the conventional visual inspection or image inspection using a television camera, for the leads of the mounted electronic components and the like on the back side of the printed board, there are portions that cannot be observed from the front side of the printed board. It is. Such a recently developed printed circuit board inspection apparatus is an improvement of a conventional medical X-ray diagnostic apparatus or an X-ray fluoroscope used for industrial purposes. There are those described in the gazette and those described in JP-A-3-218408.

A printed circuit board inspection apparatus described in Japanese Patent Application Laid-Open No. 2-31144 discloses an X-ray generating means for irradiating a double-sided printed circuit board with X-rays, and an X-ray transmission image of the double-sided printed circuit board. X-ray imaging means and an optical imaging means for optically imaging one surface of the double-sided printed circuit board. The X-ray imaging means (image intensifier) is also an optical imaging means (optical camera). ) Also extracts an image feature amount for the inspection of the double-sided printed circuit board. Therefore, especially in the case of an optical camera, the photographing range is set to be narrow in order to photograph the soldered portion of the electronic component on the printed circuit board at high resolution in detail.

A printed circuit board inspection apparatus described in Japanese Patent Application Laid-Open No. 3-218408 discloses an X-ray source for irradiating X-rays to an inspection target and an inspection target in which leads of electronic components are soldered to the substrate. A sample stage to be positioned and an X-ray imager (such as an image intensifier) for capturing a transmission image by X-rays emitted from the X-ray source and obliquely incident on the substrate.
And a soldering part position extracting means for extracting a position of a soldering part to be inspected based on an X-ray transmission image taken by the X-ray imaging device, wherein a front side and a rear side of the substrate are provided. In this case, the X-ray irradiation direction on the substrate is tilted so that the inspection target does not overlap with each other.

[0005]

However, in the former conventional example, since the photographing range of the optical camera with respect to the printed circuit board is set to be narrow to the inspection part and its surrounding area, the optical camera covers a wide area of the printed circuit board. Could not be taken. Therefore, it has been almost impossible to align the X-ray imaging range with respect to the inspection site on the printed circuit board while observing a wide range of images captured by the optical camera. For this reason, it takes time to adjust the range of X-ray imaging to a desired inspection site on the printed circuit board, and the inspection efficiency is reduced.

Further, in the latter conventional example, since the X-ray irradiating direction with respect to the substrate is used for imaging, the distance from the substrate surface to the imaging surface of the X-ray imaging device is reduced on the substrate surface. This may differ depending on the position, and in particular, the resolution may decrease at a portion where the distance between the substrate surface and the X-ray imaging device is long, and the X-ray inspection image may be distorted. Therefore, the soldering state of the electronic component cannot be accurately inspected.

Further, in any of the above conventional examples,
X-rays are continuously irradiated from the start to the end of the X-ray inspection, and the X-ray imaging means (image intensifier, etc.) may be deteriorated due to long-time inspection or repeated inspection. The image quality of the obtained X-ray inspection image sometimes deteriorated due to a change with time. This may make it difficult to inspect the soldering condition.

Accordingly, the present invention has been made to address the above problems, and has made it possible to easily position an inspection portion of a printed circuit board with respect to an X-ray imaging range, and to reduce distortion of an X-ray inspection image.
It can be removed, and furthermore ,
It is an object of the present invention to provide a board soldering state inspection device capable of preventing deterioration of image quality due to the above.

[0009]

In order to achieve the above object, a board soldering state inspection apparatus according to the present invention comprises an XY table on which a printed circuit board is mounted and which can move in a two-dimensional plane; An X-ray source that irradiates an X-ray to an inspection portion of the board; and an X-ray imaging unit that is disposed to face the X-ray source with the XY table interposed therebetween and captures a transmitted X-ray image of the printed board and converts the transmitted X-ray image into an electric signal. A first display for displaying an output signal from the X-ray imaging unit as an inspection image, and an optical image of a mounted state of a printed circuit board provided on one side of the XY table to generate an electric signal. A television camera for conversion, and a second display for displaying an output signal from the television camera as an image, and soldering the electronic component to a printed circuit board according to the inspection image displayed on the first display. Inspect condition In that substrate soldering state inspecting device, the television camera is intended to by the electronic components of the printed circuit board is mounted side may shoot a wide range from the imaging range by the X-ray imaging unit, and the second display Means for displaying the X-ray imaging range for the printed circuit board in the display image of the container, and further comprising an X-ray table
XY drive that is provided parallel to the device and can move in a two-dimensional plane
Attached to the mechanism, the movement of this XY drive mechanism
The XY table is synchronized in the same direction at a fixed rate.
A synchronous drive circuit for moving the X-ray source is provided.
Move the X-ray imaging unit to a position shifted to the side from the irradiation center
X-rays on the same inspection site of the printed circuit board on the XY table
It is possible to change the irradiation angle and take a picture .

A dosimeter for measuring an X-ray dose is provided in an X-ray irradiation area from the X-ray source, and an output signal of the dosimeter is input to adjust a gain of the X-ray imaging unit. Means may be provided to keep the image density constant.

Further, between the X-ray source and the X-ray imaging unit, a plurality of types of samples for image density calibration of the X-ray imaging unit are provided so as to be able to advance and retreat in an X-ray imaging region. Means for adjusting a gain and a gamma value of an image obtained when a sample is inserted into an X-ray imaging region may be provided, and compensation may be performed so that the density of an image corresponding to each sample is constant. .

[0012]

The board soldering state inspection apparatus thus configured takes a picture of the side of the printed circuit board on which the electronic components are mounted by using a television camera capable of photographing a wider range than the photographing range of the X-ray imaging unit. The display means provided in the display circuit of the display device operates to display the X-ray imaging range for the printed circuit board in the display image of the display device. This makes it possible to capture a wide range with the TV camera.
By moving the XY table on which the printed circuit board is mounted while observing the shadow image, it is possible to easily position the inspection site on the printed circuit board within the X-ray imaging range and easily determine the imaging position. Further, the X-ray imaging unit is XY
X provided parallel to the table and movable in a two-dimensional plane
Attach to the Y drive mechanism and move the XY drive mechanism.
Move the XY table in the same direction at a fixed rate
The synchronous drive circuit that moves the
X at a position shifted laterally from the center of X-ray irradiation by the X-ray source
Even if the line imaging unit is moved, the printed circuit board on the XY table
It is possible to image the same inspection site at different X-ray irradiation angles.
Wear. With this, the incident surface of the X-ray imaging unit and the print
The printed circuit board etc. without changing the distance to the board
Obliquely incident X-rays
Even in this case, the distortion of the inspection image can be removed.

In addition, a dosimeter for measuring the dose of X-rays is provided in the irradiation area of the X-rays from the X-ray source, and the output signal of the dosimeter is input to adjust the gain of the X-ray imaging unit. In the apparatus provided with the means, the obtained image density can be always kept constant. This makes it easier to see the X-ray inspection image.

Further, between the X-ray source and the X-ray imaging unit, a plurality of types of samples for image density calibration of the X-ray imaging unit are provided so as to be able to advance and retreat in an X-ray imaging region. In a device provided with means for adjusting the gain and gamma value of an image obtained when a sample is inserted into an X-ray imaging region, sensitivity compensation is performed so that the density of the image corresponding to each sample is constant. be able to. Thereby, the accuracy of the obtained inspection image can be improved.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is an overall configuration diagram showing an embodiment of a board soldering state inspection apparatus according to the present invention. This board soldering state inspecting device irradiates a printed board as an inspection object with X-rays, takes a transmission X-ray image thereof, and inspects a soldering state of the electronic component on the printed board.
As shown in the figure, an XY table 1, an X-ray source 2, an X-ray imaging unit 3, an X-ray camera controller 4, a first display 5a, a television camera 6, a display circuit 7, a shutter 8, a second indicator 5b, and further a dosimeter 9;
It comprises a calibration sample 10, an XY drive mechanism 11, and a synchronous drive circuit 12.

The XY table 1 has a printed circuit board 13 as an object to be inspected mounted thereon and is movable in the X and Y directions in a two-dimensional plane. The part 14 is opened and attached to a conventionally known two-dimensional moving mechanism (not shown). X
The X-ray source 2 irradiates X-rays to the inspection site of the printed circuit board 13 having its edge positioned and fixed to the opening 14 of the XY table 1 and is composed of an X-ray tube device.
For example, it is provided below the XY table 1. X
The line imaging unit 3 captures a transmission X-ray image by X-rays applied to the printed circuit board 13 and converts the image into an electric signal. For example, the line imaging unit 3 includes a high-resolution imaging tube called a “vidicon”, and the XY table It is arranged to face the X-ray source 2 with 1 interposed therebetween. The first display unit 5a receives the video signal output from the X-ray imaging unit 3 via the X-ray camera controller 4 and displays it as an inspection image, and includes, for example, a black and white or color television monitor. .

The television camera 6 optically captures the mounted state of the electronic components on the printed circuit board 13 and converts it into an electric signal. The television camera 6 is provided, for example, on the lower surface of the XY table 1 and includes a light source 15. The surface on which the electronic components of the printed circuit board 13 are illuminated by the light emission is photographed. The second display 5b displays the video signal output from the television camera 6 on a display circuit 7
And displays the image as an image, for example, a black and white or color television monitor.

Note that a shutter 8 is provided in front of the X-ray irradiation direction from the X-ray source 2 to the printed circuit board 13 on the XY table 1. This shutter 8
It is closed except at the time of X-ray inspection on the printed circuit board 13 and blocks the irradiation of X-rays from the X-ray source 2. As shown in FIG. A shutter plate 21 that can be opened and closed by a shutter controller 22.
Is to be advanced and retreated.

Here, in the present invention, the television camera 6 has a wider area than the X-ray imaging section 3 on the side of the printed circuit board 13 on which the electronic components 16 and 16 (see FIG. 2) are mounted. Can be taken. That is, the XY table 1 is provided at a lower side of the lower surface of the XY table 1 and separated by a predetermined distance.
Light 18 guided by 7 and 17 is incident. At this time, the angle at which the lens of the television camera 6 looks at the printed circuit board 13 is determined by the X-ray beam 19 emitted from the X-ray source 2 toward the X-ray imaging unit 3 as shown in FIG.
Is larger than the spread angle of the X-ray imaging unit 3, and as a result, it is possible to image a wider range than the imaging range of the X-ray imaging unit 3. Further, inside the display circuit 7, there is provided means for displaying the X-ray imaging range for the printed circuit board 13 in the display image of the second display 5b. As a result, as shown in FIG. 2, the screen of the second display 5b shows the X-ray imaging range together with the images 16 'and 16' in a state where the electronic components 16 and 16 are mounted on the printed circuit board 13. A frame 20 will be displayed. Note that this frame 20
Is not limited to the display using the solid line or the dashed line, and the brightness or color tone of the image corresponding to the portion within the frame 20 may be changed and displayed in other portions.

Further , in the present invention, the X-ray imaging section
3 is attached to the XY drive mechanism 11, and this X
A synchronous drive is provided between the Y drive mechanism 11 and the XY table 1.
A motion circuit 12 is provided. XY drive mechanism 11
Moves the X-ray imaging unit 3 in a two-dimensional plane as shown in FIG.
The XY table 1 is moved in the X and Y directions.
Provided in parallel with the conventional two-dimensional moving mechanism.
Consisting of Then, the synchronous drive circuit 12 includes the XY drive device.
The XY table 1 is the same at a fixed rate for the movement of the structure 11.
It moves in synchronization with the direction, and each drive unit
(Not shown)
I have. This means that the X-ray imaging unit 3 has a high resolution
When an image pickup tube of a degree is used, the incident surface of the X-ray image pickup unit 3
Must be as close as possible to the printed circuit board 13
Is the distance between the incident surface of the X-ray imaging unit 3 and the printed circuit board 13.
The printed circuit board 13 and the mounting electronics without changing the separation
X-ray photography to change the angle of transmitted X-rays to the product
The incident surface of the image unit 3 is kept parallel to the plate surface of the printed circuit board 13.
To be able to move freely in a two-dimensional plane
It is.

The movement control by the synchronous drive circuit 12 in this case
You are as follows. Now, if you control the movement in the X direction,
Then, from the focal point of the X-ray radiation of the X-ray source 2,
The distance to the upper surface is L ₁ , and the distance to the incident surface of the X-ray imaging unit 3 is L ₁ .
Let L ₂ be the distance from the center of X-ray irradiation by X-ray source 2
The movement distance in the X direction of the printed board 13 x _1, X-ray imaging
The X-direction moving distance of the parts 3 When x _2, between these
Control is performed so that the following relationship is established. x ₂ : x ₁ = L ₂ : L ₁ As a result, the same on the printed circuit board 13 before and after the movement.
It is possible to photograph the inspection site.

In this state, as shown in FIG.
Soldering of the leads 24 of the electronic component 16 mounted on the substrate 13
The X-ray transmission path 25 is
If the lead 24 is perpendicular to the
Since the X-ray absorption by the rising portion becomes large, the lead 24
The adhesion state of the lower solder 27 is not clearly understood. But,
In FIG. 6, the printed circuit board 13 and the X-ray imaging unit 3 are exemplified.
Respectively on the left side when moved by x _1, x ₂ if, shown in Figure 7
As shown in FIG.
In this case, and in this case, the lead 24 is
X-rays from the lead 24 are reduced due to the reduced distance
The absorption is reduced, and the contact of the solder 27 under the lead 24 is reduced.
The wearing state can be observed well.

A dosimeter 9 is provided in an irradiation area of the X-ray from the X-ray source 2. This dosimeter 9
As shown in FIG. 3, the X-ray source 2 measures the dose of X-rays emitted from the X-ray source 2 toward the printed circuit board 13 and includes, for example, an ionization chamber or a counter tube. Has reached within. Further, inside the X-ray camera controller 4, there is provided means for inputting the measurement signal output from the dosimeter 9 and adjusting the gain of the image from the X-ray imaging unit 3. In this case, the dosimeter 9
Measures the generated X-ray dose of the X-ray source 2 and sends an output signal corresponding to the X-ray dose to the X-ray camera controller 4. Then, the X-ray camera controller 4 adjusts the gain of the image of the X-ray imaging unit 3 according to the measurement result input from the dosimeter 9. That is, the gain is increased when the amount of generated X-ray from the X-ray source 2 is small, and the gain is reduced when the amount of generated X-ray is large. As a result, control is performed so that the density of the inspection image captured by the X-ray imaging unit 3 and displayed on the first display unit 5a is always constant.

Further, a calibration sample 10 is provided between the X-ray source 2 and the X-ray imaging unit 3, as shown in FIG. Since the sensitivity of the X-ray imaging unit 3 decreases with time, the calibration sample 10 is used to calibrate the density of an image to compensate for the decrease in sensitivity. For example, as shown in FIG. X-ray absorption coefficient is constant and plate thickness is t ₁ ,
It is made of a plate material which changes sequentially as t ₂ , t ₃ , t ₄ , t ₅ (t ₁ > t ₂ > t ₃ > t ₄ > t ₅ ), and can be moved into and out of the X-ray imaging area by the drive unit 23. It is provided in. And X
Inside the X-ray camera controller 4, means for adjusting the gain and the gamma value of an image obtained when the calibration sample 10 is inserted into the X-ray imaging region is provided.

In this case, first, the calibration sample 10 is advanced into the imaging region of the X-ray imaging unit 3 by the driving unit 23, and is positioned in front of the incident surface. Next, X-rays are emitted from the X-ray source 2 with nothing placed on the XY table 1, and an X-ray image transmitted through the calibration sample 10 is captured by the X-ray imaging unit 3. At this time, the dosimeter 9 measures the generated X-ray dose from the X-ray source 2 and sends the signal to the X-ray camera controller 4. Then, the X-ray camera controller 4 controls the X-ray imaging unit 3
And the signal from the dosimeter 9 are input to the calibration sample 1
The relationship between the brightness change on each plate thickness t ₁ ~t ₅ and the image of 0 is recorded as the initial value. Thereafter, the gain and the gamma value of the X-ray camera controller 4 are adjusted using the calibration sample 10 at appropriate time intervals so that the relationship between the plate thickness and the luminance change on the image becomes equal to the initial value. Adjust it. Thereby, it is possible to compensate for a decrease in sensitivity of the X-ray imaging unit 3 due to a temporal change.

Note that the calibration sample 10 is
However, the present invention is not limited to this. For example, a plate serving as a sample may be attached to an appropriate portion of the XY table 1, and the plate may be photographed during calibration. Alternatively, the printed circuit board 13 itself may be used as a plate material for calibration to determine an initial value for calibration.

Next, the overall operation of the thus-configured board soldering state inspection apparatus will be described. First,
Prior to the inspection of the printed circuit board 13, the calibration sample 10 is set in the imaging area of the X-ray imaging unit 3 without placing the printed circuit board 13 on the XY table 1, as shown in FIG. X-rays are radiated from 2 and the calibration sample 1
Shoot 0. Then, the signals from the X-ray imaging unit 3 and the dosimeter 9 are input by the X-ray camera controller 4,
The state of the luminance change when the calibration sample 10 is used is recorded as an initial value.

In this state, the printed circuit board 13 is placed and fixed on the XY table 1 in FIG. At this time, the electronic component 16 mounted on the printed circuit board 13 faces the side where the television camera 6 is installed. Next, light is applied to the printed circuit board 13 by turning on the light source 15, and light from this board surface is guided by mirrors 17, 17 and photographed by the television camera 6, and as shown in FIG.
6 is displayed on the second display 5b. At this time, a frame 20 indicating the X-ray imaging range is simultaneously displayed on the screen of the second display 5b. Then, the operator moves the XY table 1 while looking at the screen of the display 5b, and moves the frame 20 of the second display 5b shown in FIG.
It is set so that an image around the inspection site of the printed circuit board 13, that is, the periphery of the lead 24 of the target electronic component 16 is located in the inside. As a result, the desired examination site is correctly positioned within the imaging range of the X-ray imaging unit 3. At the time of positioning of the inspection site, the shutter plate 21 is advanced and the shutter 8 is closed as shown in FIG. Therefore, the X-rays radiated from the X-ray source 2 are blocked by the shutter 8 and are not irradiated on the printed circuit board 13 and the X-ray imaging unit 3. From this, it is possible to prevent the X-ray imaging unit 3 from deteriorating.

Thereafter, the shutter 8 is opened by retracting the shutter plate 21. Then, as shown in FIG. 1, the X-ray radiated from the X-ray source 2 is irradiated on the printed circuit board 13, and the X-ray transmission image is captured by the X-ray imaging unit 3 and is displayed on the first display 5 a. The inspection image is displayed. Then, by observing the X-ray inspection image displayed on the first display 5a, it is inspected whether the soldering state of the electronic component 16 to the printed board 13 is good. At this time, as shown in FIG. 7, when the rising portion of the lead 24 of the electronic component 16 and the irradiation direction of the X-ray overlap and the adhesion state is not well understood, as shown in FIG. 13 may be moved in synchronization with each other, and the X-ray transmission path 26 may be inclined obliquely. This
, The XY driving mechanism 11 is simply
Only by instructing the synchronous movement between the
And that both are moved synchronously in the same direction at a constant rate
The same inspection site on the printed circuit board 13 easily and quickly
To a position shifted laterally from the X-ray irradiation center
Can be. Therefore, the same inspection site on the printed circuit board 13
Moving operation when changing the X-ray irradiation angle is easy.
You. Note that, as described above, the X-ray imaging unit 3 and the printed circuit board 1
When the shutter 3 is moved in synchronization with the shutter 3, the shutter plate 21 is advanced to close the shutter 8 as shown in FIG. When the movement is completed, the shutter 8 is opened to restart the inspection.

By the above operation, the soldering state of the electronic component 16 to the printed circuit board 13 is inspected. At appropriate use intervals or time intervals, X-ray imaging is performed using the calibration sample 10 shown in FIG. What is necessary is just to compensate for the decrease in sensitivity of the unit 3 due to the aging.

[0031]

The present invention has been configured as described above.
The side on which the electronic components are mounted of the printed circuit board is photographed by a television camera capable of photographing a wider area than the photographing range by the X-ray imaging unit, and the display means of the second display is provided with a display circuit provided in a display circuit. The X-ray imaging range for the printed circuit board can be displayed in the display image. This allows a wide range of images captured by the TV camera to be viewed.
The XY table on which the printed circuit board is placed is moved while observing the position of the inspection site of the printed circuit board within the X-ray imaging range.
Positioning can be easily performed, and the photographing position can be easily determined. Further, the X-ray imaging unit is stored in an XY table.
XY drive mechanism provided in parallel and movable in a two-dimensional plane
And the movement of the XY drive mechanism.
The XY table is moved synchronously in the same direction at a fixed rate
Since a synchronous drive circuit is provided for the X-ray source,
Move the X-ray imaging unit to a position shifted laterally from the
Even if the same inspection site on the printed circuit board on the XY table
It is possible to change the beam irradiation angle and shoot. This
The distance between the incident surface of the X-ray imaging unit and the printed circuit board.
The angle of the transmitted X-ray to the printed circuit board etc. without changing
Inspection of obliquely incident X-rays with variable degrees
Image distortion can be removed. At this time, simply
An XY drive mechanism and an XY table for the synchronous drive circuit
Only by instructing synchronous movement of
Will be moved synchronously in the same direction, the printed circuit board
Easily and quickly on the same inspection site from the X-ray irradiation center
Can be moved to a position shifted. Therefore,
Of the same inspection site on the printed circuit board with different X-ray irradiation angles
Is easy to move.

Further, a dosimeter for measuring the dose of X-rays is provided in the irradiation area of the X-rays from the X-ray source, and the output signal of the dosimeter is inputted to adjust the gain of the X-ray imaging unit. In the apparatus provided with the means, the obtained image density can be always kept constant. This makes it easier to see the X-ray inspection image.

Further, between the X-ray source and the X-ray imaging unit, a plurality of types of samples for image density calibration of the X-ray imaging unit are provided so as to be able to advance and retreat in an X-ray imaging region. In a device provided with means for adjusting the gain and gamma value of an image obtained when a sample is inserted into an X-ray imaging region, sensitivity compensation is performed so that the density of the image corresponding to each sample is constant. be able to. Thereby, the accuracy of the obtained inspection image can be improved.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of a board soldering state inspection apparatus according to the present invention.

FIG. 2 is a diagram for explaining an operation of a television camera and an image thereof.

FIG. 3 is a diagram for explaining the operation of the dosimeter.

FIG. 4 is a diagram for explaining the operation of a calibration sample.

FIG. 5 is an explanatory view showing the shape of the calibration sample.

FIG. 6 is a diagram for explaining the operation of an XY table and an XY drive mechanism.

FIG. 7 is an explanatory diagram showing a change in an X-ray transmission path with respect to a lead of an electronic component mounted on a printed board.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... XY table 2 ... X-ray source 3 ... X-ray imaging part 4 ... X-ray camera controller 5a, 5b ... Display 6 ... TV camera 7 ... Display circuit 9 ... Dosimeter 10 ... Calibration sample 11 ... XY drive mechanism 12 ... Synchronous drive circuit 13 ... Printed circuit board 16 ... Electronic components 20 ... Frame

Claims (3)

(57) [Claims] 1. An XY table on which a printed circuit board is mounted and movable in a two-dimensional plane on an upper surface, an X-ray source for irradiating an inspection portion of the printed circuit board with X-rays, and the XY table interposed therebetween. An X-ray imaging unit that is arranged to face the X-ray source and captures a transmitted X-ray image of the printed circuit board and converts it into an electric signal; and a first display that displays an output signal from the X-ray imaging unit as an inspection image. A television camera provided on one side of the XY table for optically photographing the mounting state of the printed circuit board and converting the photographed state into an electric signal, and a second display for displaying an output signal from the television camera as an image And
In the board soldering state inspection device for inspecting the soldering state of the electronic component to the printed board by the inspection image displayed on the first display, the television camera is mounted on the side of the printed board on which the electronic component is mounted. Means for capturing an image of a wider area than the imaging range of the X-ray imaging unit, and means for displaying an X-ray imaging range for a printed circuit board in a display image of the second display , Further X-ray
The imaging unit is provided in parallel with the XY table and is in a two-dimensional plane.
Attached to an XY drive mechanism that can move
The XY table at a fixed rate with respect to the movement of the Y drive mechanism
A synchronous drive circuit for synchronously moving in the same direction,
At a position shifted laterally from the center of X-ray irradiation by the X-ray source
Printed circuit board on XY table even when moving X-ray imaging unit
To change the X-ray irradiation angle for the same examination site
Board soldering condition inspection apparatus being characterized in that the. 2. An X-ray irradiating area in the X-ray irradiation area from the X-ray source.
A dosimeter for measuring the dose of the radiation is provided, and a means for inputting an output signal of the dosimeter and adjusting the gain of the X-ray imaging unit is provided so that the image density is always constant. The board soldering state inspection device according to claim 1, wherein 3. The X-ray source between the X-ray source and the X-ray imaging unit.
A plurality of types of samples for image density calibration of the X-ray imaging unit are provided so as to be able to advance and retreat in the X-ray imaging region, and the gain and gamma value of an image obtained when each of the samples is inserted into the X-ray imaging region. 3. A board soldering state inspection apparatus according to claim 1, further comprising means for adjusting the image density, and compensating the density of an image corresponding to each sample to be constant.