KR101041840B1 - Defect-inspecting apparatus and contol method therof - Google Patents

Abstract

Disclosed is a defect inspection apparatus for allowing an image of an inspection object displayed on a display to be moved at a constant speed regardless of magnification. The defect inspection apparatus of the present invention includes a horizontal moving unit for moving the inspection object in a first direction located in the same horizontal plane and in a second direction perpendicular to the first direction, and in a third direction perpendicular to the first and second directions. A positioning unit including a vertical moving unit for moving to and changing a position of the inspection object; A light source for irradiating light to the inspection object; An image detector for detecting an image projected when the light source irradiates a light beam on the inspection object; A display unit configured to display an image detected by the image detector; And a controller for controlling the positioning unit to displace the position of the inspection object based on the _pixel displacement speed V _pixel of the image displayed on the display unit.

X-ray, scan, position, pixel, speed, displacement

Description

Defect-inspecting apparatus and contol method therof}

The present invention relates to a defect inspection apparatus and a control method for inspecting defects of inspection target parts, such as semiconductor chips and resistance chips, which are embedded in an inspection object such as a printed circuit board (PCB) of an electric and electronic device. .

Generally, a defect inspection apparatus, for example, an X-ray inspection apparatus, irradiates an X-ray to an inspection object such as a printed circuit board set at an inspection position in a cabinet manufactured to form a space for X-ray shielding. After imaging the image projected through the inspection object with the X-ray detector, inspection such as soldering parts of semiconductor chips, resistor chips, etc. of the printed circuit board through the image information output from the X-ray detector and displayed on the monitor It is configured to determine whether or not the inspection target site of the object.

The X-ray inspection apparatus includes a positioning unit that rotates and moves the inspection object in the X, Y, and Z-axis directions at the time of imaging to enable imaging of the inspection object at various positions and angles. Positioning unit is installed in the X-, Y-, and Z-axis moving parts for moving the inspection object in the X, Y, and Z-axis directions, and the X-, Y-, and Z-axis moving parts, respectively. And a rotational moving unit for rotating the axial and Z-axis moving units.

In general, the X-axis, Y-axis, and Z-axis moving units and the rotating unit move and rotate at speeds of mm / sec and deg / sec previously set in the controller through input means such as a keyboard, respectively. Therefore, the X-ray inspection apparatus rotates the inspection object by the rotary movement unit during imaging, or moves it to the X, Y, and Z-axis moving units in front, rear, left and right, and up and down, so as to capture the inspection object at various positions and rotation angles. can do. As a result, the X-ray inspection apparatus may acquire various types of images of the inspection target region of the inspection object, thereby improving inspection accuracy.

However, in the conventional X-ray inspection apparatus as described above, when the inspection object is moved in the Z-axis direction by the Z-axis moving unit in order to capture the inspection target portion of the inspection object in various different Z-axis directions during the inspection, The geometric magnification X of the X-ray inspection apparatus, that is, the magnification of the image of the inspection object displayed on the monitor is changed.

More specifically, the magnification X is expressed as the distance between the focusing spot of the target of the X-ray source and the image detector (b) / the distance (a) between the focusing spot of the target of the X-ray source and the inspection object. When the inspection object moves in the Z-axis direction toward the X-ray source, for example, in the lower direction, the magnification X increases, and when the inspection object moves in the Z axis direction toward the image detector, that is, in the upper direction, X) becomes small.

Therefore, even if the moving speed of the X- and Y-axis moving parts or the rotational speed of the rotary moving part is set to mm / sec or deg / sec of the same value, it is displayed on the monitor when the inspection object is moved back, forth, left, and right during inspection. The moving speed or rotational speed of the image of the inspection object to be changed depends on the magnification X which changes depending on the position of the inspection object in the Z-axis direction. That is, even though the moving speed or the rotational speed of the actual inspection object is the same, the image of the inspection object displayed on the monitor moves or rotates quickly in the case of a relatively high magnification, and moves or rotates slowly in the case of a relatively low magnification. As a result, it is difficult for the inspector to determine whether the inspected part is defective at a high magnification rate, and it is difficult to determine whether the inspected part is defective. At a too low magnification rate, the inspector speed of the inspected part is slowed down. And / or inspection efficiency is lowered. Therefore, in the conventional X-ray inspection apparatus, when the magnification X is changed in order to move and rotate the inspection object at a speed suitable for inspection, the inspector may move the X- and Y-axis moving portions through an input means such as a keyboard. There is a hassle to reset the movement speed and rotation speed of the moving part.

In addition, the conventional X-ray inspection apparatus is moved in the X-axis, Y-axis and Z-axis direction and / or rotation so that the inspection object does not deviate from the screen of the monitor when the inspection object is rotated or the image detector is tilted at a predetermined angle in the form of an arc. An automatic focusing and tracing (AFT) unit for moving the moving unit is provided. The auto focusing and tracing portion is controlled in an offset movement manner. That is, if the moving distance value of the inspection object is input through an input means such as a keyboard, if necessary, the controller drives the auto focusing and tracing unit to move the inspection object by the input movement distance value, thereby driving the X, Y, and Z axes. Move the axial moving part and / or the rotating moving part. Therefore, the user is inconvenient to input the necessary moving distance value through the input means every time the object to be rotated or the image detector is tilted at a predetermined angle.

In addition, in the conventional X-ray inspection apparatus, when the inspection object is rotated by the rotary mover, since the rotary mover is disposed below the X-axis, Y-axis and Z-axis direction moving parts, shown in FIGS. 4A and 5A. As described above, the moving axes in the X-axis and Y-axis directions (X, Y) of the X-axis and Y-axis moving parts rotate together. As a result, when the inspection object is rotated at a predetermined angle by the rotary moving unit and then moved back and forth, left and right by the X and Y axis moving units, the inspection object is the x 'axis and the y' axis, which are the coordinate standards of the monitor screen. Rather than moving along the direction (see FIGS. 4A and 5A), it moves along the X and Y axis directions X and Y, which are the moving directions of the X and Y axis moving parts. Therefore, in order to move the inspection object to a specific inspection position by the X-axis and Y-axis moving parts, the inspector intentionally memorizes the rotation angles rotated by the X-axis and Y-axis moving parts by the rotary moving part, It is necessary not to forget the moving direction of the Y-axis moving part. If the inspector does not remember the rotation angle rotated by the X- and Y-axis moving parts, the inspector may search for and search again the rotation angle input to the controller, or move the value of the moving distance to move the inspection object back, forth, left, or right. There is a hassle to check the moving direction of the X-axis and Y-axis direction moving parts by actually moving the X-axis and Y-axis moving parts by input.

The present invention was created in view of the above-described problems in the related art, and an object of the present invention is to allow an image of an object to be displayed on the display unit to be moved at a constant speed regardless of magnification. An object of the present invention is to provide a defect inspection apparatus having improved accuracy and efficiency and a control method thereof.

Another object of the present invention is to provide a defect inspection apparatus and a control method thereof, by which a positioning unit for controlling the position of an inspection object can be controlled by a real-time movement method, thereby improving inspection efficiency.

Still another object of the present invention is to make it easy to track the moving direction of the inspection object by moving the inspection object to the coordinate reference of the display unit when the inspection object is moved back, front, left, and right after the rotation, thereby improving the inspection efficiency. A defect inspection apparatus and its control method are provided.

The defect inspection apparatus according to an embodiment of the present invention for achieving the object as described above, the horizontal moving unit for moving the inspection object in the first direction and the second direction perpendicular to the first direction located on the same horizontal plane and inspection A positioning unit having at least one of vertical moving parts for moving the object in a third direction perpendicular to the first and second directions, the positioning unit changing a position of the inspection object; A light source for irradiating light to the inspection object; An image detector for detecting an image projected when the light source irradiates a light beam on the inspection object; A display unit configured to display an image detected by the image detector; And a controller for controlling the positioning unit to displace the position of the inspection object based on the _pixel displacement speed V _pixel of the image displayed on the display unit.

Here, the controller may control the horizontal moving unit to move the inspection object at the first linear movement speed V _support (mm / sec) calculated by the following equation when the inspection object is moved in the first direction or the second direction. have.

V _support (mm / sec) = V ' _pixel (pixel / sec) * D _pixel (mm / pixel)

Here, the V ' _pixel (pixel / sec) is input to the controller in advance, and the pixel displacement velocity value of the image displayed on the display unit when the inspection object is moved in the first direction or the second direction,

D _pixel (mm / pixel) is the physical distance of one pixel.

D _pixel (mm / pixel) is preferably calculated by the following equation.

D _pixel (mm / pixel) = D / (X * X '* X "* cximage)

Here, D is the size (mm) of the image displayed on the display unit,

X is the geometric magnification of the defect inspection device,

X 'is the magnification of the image detector or the flat detector of the image detector,

X "is the magnification of the image detector's camera,

cximage is the resolution of the camera in pixels.

In this case, X is TD / TT, X 'is DO / DI, X "is preferably D / C.

Where TD is the distance (mm) between the focus spot of the target of the light source and the image detector,

TT is the distance between the focusing spot of the target of the light source and the inspection object (mm),

DO is the length of the output face of the image multiplier or flat panel detector (mm),

DI is the length of the input surface of the image multiplier or flat panel detector (mm),

C is the field of view (FOV) of the camera (mm).

The positioning unit may further include a rotation moving unit for rotating the inspection object. At this time, it is preferable that the rotary mover is located at least below the horizontal mover to rotate the horizontal mover to rotate the inspection object.

Optionally, the defect inspection apparatus further supports a variable unit which supports the image detector and variably moves the image detector in the fourth direction in an arc shape with respect to a certain tilt center so as to have a plurality of incident angles with respect to any coordinate point of the inspection object. It may include. In this case, the positioning unit includes an automatic focusing and tracing (AFT) unit for moving at least two of the horizontal moving unit, the rotating moving unit, and the vertical moving unit in a fourth direction in which the image detector is variably moved. It includes more.

At this time, the controller automatically focuses and tracing to move at least two of the horizontal moving part, the rotating moving part and the vertical moving part to the second linear moving speed V ' _support (mm / sec) calculated by the following equation. It is desirable to control wealth.

V ' _support (mm / sec) = V " _pixel (pixel / sec) * D _pixel (mm / pixel)

Here, the V ″ _pixel (pixel / sec) is input to the controller in advance, and the image displayed on the display unit when at least two of the horizontal moving unit, the rotating moving unit and the vertical moving unit of the positioning unit are moved. The displacement velocity of the pixel.

In addition, the controller may further include a positioning unit, a variable unit, and a joystick input unit for finely and continuously controlling the automatic focusing and tracing unit. The joystick input unit may be composed of a plurality of joysticks or buttons that continuously transmit the movement command in the operated direction to the controller so as to control the horizontal moving unit, the rotating moving unit, the vertical moving unit, and the variable unit of the positioning unit, respectively. have.

When using the joystick input section to control each of the horizontal moving section, the rotating moving section, and the vertical moving section of the positioning unit, the controller is moved from the joystick input section to the horizontal moving section, the rotating moving section, and the vertical moving section of the positioning unit. The horizontal moving part, the rotating moving part, and the vertical moving part of the positioning unit are controlled to move the inspection object according to the same correction amount for each moving command when the moving command for each is continuously received.

However, when controlling the variable unit using the joystick input unit, the controller moves the image detector according to the same correction amount for each movement command when the movement command for the variable unit is continuously received from the joystick input unit. At the same time as the control object, the inspection object is the same as the moving direction of the image detector according to the first variation correction amount (D _aft) that varies depending on the tilt angle of the image detector variable shifted for each movement command for the variable unit Control the automatic focusing and tracing portion or the horizontal movement portion to move in the direction.

At this time, it is preferable that the first variation correction amount _Daft is calculated by the following equation.

D _aft = {T _cent D * TT sin (θ _current + θ _offset )} / {TT _cent + T _cent D cos (θ _current +

θ _offset )}-{T _cent D * TT sin (θ _current )} / {TT _cent + T _cent D cos (θ _current )}

Here, TT is the distance between the focus spot of the target of the light source and the inspection object

T _cent D is the distance between the tilt center of the image detector and the image detector,

TT _cent is the distance from the focus spot of the target of the light source to the tilt center,

θ _current is the tilt angle of the variably shifted image detector with respect to the tilt center,

θ _offset is the tilt angle of the image detector variable shifted with respect to the tilt center by one shift command for the variable unit.

In addition, when the image detector is variably moved at a predetermined angle with respect to the tilt center by the variable unit, and the joystick input unit is used to control the vertical movement unit, the controller continuously receives a movement command to the vertical movement unit from the joystick input unit. automatically the target object to the vertical is to move in the same fourth direction as the moving direction of the image detector according to the second variation correction amount (D _'aft) corresponding to the third direction, the moving distance for each movement command on the Eastern time the Control focusing and tracing unit or horizontal moving unit.

At this time, the second variation correction amount D ' _aft is preferably calculated by the following equation.

D ' _aft = ± (Z _offset * T _cent D sin (θ ' _current ) / (TT _cent + T _cent D cos (θ ' _current )｝

Here, Z _offset is the third moving distance of the inspection object to be moved by one movement command with respect to the vertical movement unit,

θ ' _current is the tilt angle of the image detector which is variably shifted with respect to the tilt center when the object starts to move in the third direction.

In addition, when the inspection object is rotated at a predetermined angle by the rotation moving unit and moved by the horizontal moving unit, the controller displays an image of the inspection object displayed through the display unit as the first and second direction coordinates of the display unit screen. You can control it to move.

To this end, when the controller inputs a first direction movement amount mm (XD ′) for moving the image of the inspection object to the first and second direction coordinates of the display unit screen by an input means from the outside, the first direction. movement amount (mm) (XD ') a first decomposed in a first direction component and a second directional component, and calculates the first conversion movement amount (XD _{X)) (mm)} and the second conversion travel value (YD _X) (mm), this Control the horizontal moving unit to move the inspection object accordingly.

At this time, it is preferable that the first conversion shift amount XD _{X )} mm and the second conversion shift amount YD _X mm are each calculated by the following equation.

XD _X (mm) = XD '* cosδ

YD _X (mm) = XD '* sinδ

Here, δ is an angle between the first direction coordinate axis of the horizontal moving unit and the first direction coordinate axis of the display unit after the inspection object is rotated.

In addition, the controller may move the second direction movement amount when the second direction movement amount mm YD ′ for moving the image of the inspection object to the first and second direction coordinate reference points of the display unit by an input means from the outside. (mm) (YD ') is decomposed into the first direction component and the second direction component to calculate the third transformed shift amount XD _Y (mm) and the fourth transformed shift amount YD _Y (mm), and accordingly check Control the horizontal moving unit to move the object.

At this time, it is preferable that the third transform movement amount XD _Y (mm) and the fourth transform movement amount YD _Y (mm) are respectively calculated by the following equations.

XD _Y (mm) = YD '* sinδ'

YD _Y (mm) = YD '* cosδ'

Here, δ 'is an angle between the second direction coordinate axis of the horizontal moving unit and the second direction coordinate axis of the display unit after the inspection object is rotated.

In a preferred embodiment, the inspection object is a printed circuit board, the first, second, third and fourth directions are in the X, Y, Z and Y directions, respectively, and the light source generates an X-ray. It may be an X-ray source.

According to another embodiment of the present invention, the defect inspection apparatus is a horizontal moving unit for moving the inspection object in the first direction and the second direction perpendicular to the first direction located on the same horizontal plane, the inspection object and the first and second directions Automatic focusing and tracing for moving at least two of the vertical moving part for moving in the third vertical direction, the rotating moving part for rotating the inspection object, and the horizontal moving part, the rotating moving part, and the vertical moving part in the fourth direction ( An positioning unit having an automatic focusing-tracing (AFT) unit to change a position of the inspection object; A light source for irradiating light to the inspection object; An image detector for detecting an image projected when the light source irradiates a light beam on the inspection object; A display unit configured to display an image detected by the image detector; A variable unit which supports the image detector and variably moves the image detector in a fourth direction with respect to a predetermined tilt center to have a plurality of incident angles with respect to any coordinate point of the inspection object; And a controller including a joystick input unit for finely and continuously controlling at least one of the positioning unit and the variable unit.

      Here, when controlling each of the horizontal moving part, the rotating moving part, and the vertical moving part of the positioning unit by using the joystick input part, the controller is moved from the joystick input part to the horizontal moving part, the rotating moving part, and the vertical moving part of the positioning unit. When the movement command for each of the eastern parts is received continuously, the horizontal moving part, the rotating moving part, and the vertical moving part of the positioning unit are controlled to move the inspection object according to the same correction amount for each moving command.

In addition, when controlling the variable unit using the joystick input unit, the controller moves the image detector according to the same correction amount for each movement command when the movement command for the variable unit is continuously received from the joystick input unit. At the same time as the control object, the inspection object is the same as the moving direction of the image detector according to the first variation correction amount (D _aft) that varies depending on the tilt angle of the image detector variable shifted for each movement command for the variable unit Control the automatic focusing and tracing unit or horizontal movement unit to move in the direction.

At this time, it is preferable that the first variation correction amount _Daft is calculated by the following equation.

D _aft = {T _cent D * TT sin (θ _current + θ _offset )} / {TT _cent + T _cent D cos (θ _current +

θ _offset )}-{T _cent D * TT sin (θ _current )} / {TT _cent + T _cent D cos (θ _current )}

In addition, when the image detector is variably moved at a predetermined angle with respect to the tilt center by the variable unit, and the joystick input unit is used to control the vertical movement unit, the controller continuously receives a movement command to the vertical movement unit from the joystick input unit. automatically the target object to the vertical is to move in the same fourth direction as the moving direction of the image detector according to the second variation correction amount (D _'aft) corresponding to the third direction, the moving distance for each movement command on the Eastern time the Control focusing and tracing unit or horizontal moving unit.

At this time, the second variation correction amount D ' _aft is preferably calculated by the following equation.

D ' _aft = ± (Z _offset * T _cent D sin (θ ' _current ) / (TT _cent + T _cent D cos (θ ' _current )｝

In a preferred embodiment, the inspection object is a printed circuit board, the first, second, third and fourth directions are in the X, Y, Z and Y directions, respectively, and the light source generates an X-ray. It may be an X-ray source.

       According to another embodiment of the present invention, the defect inspection apparatus is a horizontal moving unit for moving the inspection object in the first direction and the second direction perpendicular to the first direction located on the same horizontal plane, the inspection object in the first and second directions A positioning unit which includes a vertical moving unit for moving in a third direction perpendicular to the vertical direction, and a rotating moving unit for rotating the inspection object, wherein the positioning unit changes the position of the inspection object; A light source for irradiating light to the inspection object; An image detector for detecting an image projected when the light source irradiates a light beam on the inspection object; A display unit configured to display an image detected by the image detector; And when the inspection object is rotated at a predetermined angle by the rotation moving unit and then moved by the horizontal moving unit, the image of the inspection object displayed through the display unit moves to the first and second direction coordinates of the display unit screen. The controller; characterized in that it comprises a.

Here, the controller is a first direction movement amount when the first direction movement amount (mm) (XD ') for moving the image of the inspection object to the first and second direction coordinate reference of the display unit screen by the input means from the outside (mm) (XD ') is decomposed into a first direction component and a second direction component to calculate the first transformed shift amount XD _X (mm) and the second transformed shift amount YD _X (mm), and accordingly check Control the horizontal moving unit to move the object.

At this time, it is preferable that the first conversion shift amount XD _X (mm) and the second conversion shift amount YD _X (mm) are respectively calculated by the following equations.

XD _X (mm) = XD '* cosδ

YD _X (mm) = XD '* sinδ

In addition, the controller may move the second direction movement amount when the second direction movement amount mm YD ′ for moving the image of the inspection object to the first and second direction coordinate reference points of the display unit by an input means from the outside. (mm) (YD ') is decomposed into the first direction component and the second direction component to calculate the third transformed shift amount XD _Y (mm) and the fourth transformed shift amount YD _Y (mm), and accordingly check Control the horizontal moving unit to move the object.

At this time, it is preferable that the third transform movement amount XD _Y (mm) and the fourth transform movement amount YD _Y (mm) are respectively calculated by the following equations.

XD _Y (mm) = YD '* sinδ'

YD _Y (mm) = YD '* cosδ'

In a preferred embodiment, the inspection object is a printed circuit board, the first, second, third and fourth directions are in the X, Y, Z and Y directions, respectively, and the light source generates an X-ray. It may be an X-ray source.

According to another embodiment of the present invention, a control method of a defect inspection apparatus includes the steps of inputting a pixel displacement velocity value of an image of an inspection object displayed on a display unit; And moving the inspection object to the first linear movement speed V _support (mm / sec) calculated based on the input pixel displacement speed value when the inspection object is moved.

The first linear moving speed V _support (mm / sec) may be calculated by the following equation.

V _support (mm / sec) = V ' _pixel (pixel / sec) * D _pixel (mm / pixel)

At this time, D _pixel (mm / pixel) is preferably calculated by the following equation.

D _pixel (mm / pixel) = D / (X * X '* X "* cximage)

In this case, X is TD / TT, X 'is DO / DI, X "is preferably D / C.

According to another embodiment of the present invention, a control method of a defect inspection apparatus includes a step of continuously moving a moving command to an image detector by using a joystick input unit to variably move the image detector to an arc shape; And moving the inspected object in the same direction as the moving direction of the image detector according to the first variation correction amount (D _aft) that varies according to the tilt angle of the image detector variablely shifted with respect to each moving command with respect to the image detector. Characterized in that.

Here, it is preferable that the first fluctuation correction amount _Daft is calculated by the following equation.

D _aft = {T _cent D * TT sin (θ _current + θ _offset )} / {TT _cent + T _cent D cos (θ _current +

θ _offset )}-{T _cent D * TT sin (θ _current )} / {TT _cent + T _cent D cos (θ _current )}

In addition, the control method of the defect inspection apparatus of the present invention comprises the step of moving the inspection object in the vertical direction by using the joystick input unit after the image detector is variably moved at a predetermined angle with respect to the tilt center, and from the joystick input unit to the inspection object along the object to be inspected when the vertical movement instruction is continuously received by the second fluctuation correction amount (D _'aft) corresponding to the vertical direction, the moving distance for each movement command, the step of moving in the same direction as the moving direction of the image detector, It may further include.

At this time, the second variation correction amount D ' _aft is preferably calculated by the following equation.

D ' _aft = ± (Z _offset * T _cent D sin (θ ' _current ) / (TT _cent + T _cent D cos (θ ' _current )｝

According to another embodiment of the invention, the control method of the defect inspection apparatus

The first direction movement amount for moving the inspection object based on the first and second direction coordinates of the display unit screen when the inspection object is rotated at a predetermined angle by the rotation moving unit and then moved in the first direction by the horizontal moving unit ( mm) (XD '); And moving the inspection object according to the first transformed movement amount XD _X (mm) and the second transformed movement amount YD _X (mm) calculated based on the input first direction movement amount mm (XD ′). It is characterized by including.

At this time, it is preferable that the first conversion shift amount XD _X (mm) and the second conversion shift amount YD _X (mm) are respectively calculated by the following equations.

XD _X (mm) = XD '* cosδ

YD _X (mm) = XD '* sinδ

In addition, the control method of the defect inspection apparatus of the present invention display the inspection object when the inspection object is rotated at a predetermined angle by the rotation moving unit and then moved to the second direction perpendicular to the first direction by the horizontal moving unit display unit screen Inputting a second direction movement amount (mm) YD ′ for moving to the first and second direction coordinates of the first and second directions; And moving the inspection object according to the third transformed movement amount XD _Y (mm) and the fourth transformed movement amount YD _Y (mm) calculated based on the input second direction movement amount mm (YD ′). It may further include.

At this time, the third conversion movement amount XD _Y (mm) and the fourth conversion movement amount YD _Y (mm) are preferably calculated by the following equations, respectively.

XD _Y (mm) = YD '* sinδ'

YD _Y (mm) = YD '* cosδ'

The defect inspection apparatus and its control method according to the present invention, since the controller controls the positioning unit to change the position of the inspection object in the unit of the pixel displacement velocity (V _pixel ) of the image displayed on the display, the image of the inspection object during inspection Can be moved at a constant speed regardless of magnification, thereby improving inspection accuracy and efficiency.

In addition, the defect inspection apparatus of the present invention and the control method thereof includes a joystick input unit for controlling the horizontal movement unit, the vertical movement unit, the rotation movement unit, the variable unit, etc. of the positioning unit in a fine and continuous manner, thereby providing a horizontal movement unit. The vertical moving part, the rotating moving part, and the variable unit can be controlled by a real time moving method, thereby improving inspection efficiency.

In addition, the defect inspection apparatus and control method thereof according to the present invention, when controlling the variable unit by using the joystick input unit, the controller is different from the first variation correction amount (D _aft) for the movement command for each variable unit ( mm) to control the automatic focusing and tracing unit or horizontal movement unit to automatically move in the same Y-axis direction as the moving direction of the image detector, regardless of the tilt angle of the image detector in which the inspection object is variablely moved by the variable unit. It can be positioned on the X-ray axis of the image detector, thereby improving inspection efficiency.

In addition, the defect inspection apparatus and the control method of the present invention, when the image detector is moved by a variable angle with respect to the tilt center by a predetermined angle, when the controller controls the vertical moving unit using the joystick input unit, the controller is to control the inspection object Automatic focusing and tracing unit for each movement command to the vertical movement unit to move in the same Y-axis direction as the movement direction of the image detector according to the second variation correction amount D ' _aft corresponding to the Z-axis movement distance or By controlling the horizontal moving unit, the inspection object can be positioned on the X-ray axis of the image detector regardless of the moving distance in the Z-axis direction moved by the vertical moving unit, thereby improving inspection efficiency.

In addition, the defect inspection apparatus and the control method of the present invention, when the inspection object is rotated by the rotary moving unit and moved by the horizontal moving unit, the image of the inspection object displayed through the display unit is moved to the coordinate reference of the display unit screen Since it can be controlled so as to facilitate the tracking and movement of the inspection object, the inspection efficiency can be improved accordingly.

Hereinafter, a defect inspection apparatus and a control method according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a conceptual diagram illustrating an x-ray inspection apparatus 100 as a defect inspection apparatus according to an embodiment of the present invention, Figures 2a to 2c is the position of the x-ray inspection apparatus 100 shown in FIG. It is a perspective view, a side view, and a front view of the determination unit 111. FIG.

Referring to FIG. 1, the x-ray inspection apparatus 100 of the present invention includes a cabinet 101, a positioning unit 111, an x-ray source 103, an x-ray detector 105, and a controller 108. And a display unit 109.

The cabinet 101 is comprised of a chamber 101 of rectangular shape, for example made of lead (Pb) to shield the x-ray.

The positioning unit 111 is supplied into the cabinet 101 by a conveying means such as an inspection object, for example, a conveyor belt (not shown), so that the X-ray detector 105 can capture various types of stereoscopic images. It is for changing the position of the printed circuit board 104 and is arranged in the chamber 102 of the cabinet 101.

As shown in FIGS. 2A to 2C, the positioning unit 111 includes a horizontal moving part 113 and a rotating moving part 115. The horizontal moving part 113 moves the printed circuit board 104 in the first and second directions, for example, the X and Y directions (X and Y directions in the drawing) to determine the horizontal position of the printed circuit board 104. Y-axis moving member 119 and Y-axis moving member 119 for moving the support tool 117 (FIG. 2C) which supports the printed circuit board 104 at the inspection position in the Y-axis direction by moving it to ) Is composed of an X-axis direction moving member 121 for moving in the X-axis direction. The rotary moving unit 115 is for rotating the horizontal moving unit 113, and the square plate-shaped rotating body 153 supporting the X-axis moving member 121 in the lower portion of the X-axis moving member 121. Equipped. In order to move the horizontal moving part 113 and the rotating moving part 115 to the 3rd direction perpendicular | vertical to the X-axis and Y-axis direction which are 1st and 2nd direction, ie, Z-axis direction (arrow Z of drawing), The determination unit 111 further includes a vertical moving unit 160. The vertical moving unit 160 includes a Z-shaped moving body 161 having a U-shape disposed vertically under the rotation guide 155 of the rotating moving unit 115.

The configuration and operation of the horizontal moving part 113, the rotating moving part 115, and the vertical moving part 160 of the positioning unit 111 are the same as those described in detail in Korean Patent Application No. 10-2007-96918 of the applicant. Since it is the same and not the summary of this invention, detailed description is abbreviate | omitted.

Referring back to FIG. 1, the X-ray source 103 irradiates a light beam, that is, an X-ray, to the printed circuit board 104 supported by the support 117 to make a projection image. It is arranged in the central space of the Z-axis moving body 161 on the bottom of the chamber 102. The X-ray source 103 may be composed of a high voltage generator (not shown), and an X-ray tube connected to the high voltage generator and generating X-rays.

The X-ray detector 105 is an image detector for capturing an image projected when the X-ray source 103 irradiates an X-ray to the printed circuit board 104 and outputting the image signal as an image signal. ) Is installed on the upper side wall of the cabinet 101 from the support 117 above. The X-ray detector 105 is composed of an image intensofier or flat panel detector 169 and a CCD camera 172 for imaging a fluorescent image.

In addition, the X-ray detector 105 has a plurality of incident angles with respect to an arbitrary coordinate point of the inspection object, that is, an inspection target portion such as a soldering portion of an electronic component such as a semiconductor chip or a resistance chip of the printed circuit board 104. Is supported by the variable unit 180 so as to be movably installed in an arc shape with respect to the tilt center O (see FIG. 3A and FIG. 3B) in the fourth direction, for example, the Y _aft axis direction substantially the same as the Y axis direction. Can be. The variable unit 160 moves on the plate-shaped frame 181 by supporting the plate-shaped frame 181 and the X-ray detector 105 installed so as to be positioned in a floating shape in the chamber 102 of the cabinet 101. And a holder bracket 184 having a driving motor (not shown). The configuration and operation of the variable unit 180 are the same as that described in the applicant's Korean Patent Publication No. 10-2006-27507.

When the position of the X-ray detector 105 is changed, the inspection target region such as the soldering portion of the semiconductor chip, the resistance chip, etc. of the printed circuit board 104 does not deviate from the center of rotation of the rotational moving portion 115 and the imaging range and In order to maintain the focusing position, the positioning unit 111 of the X-ray inspection apparatus 100 may include a horizontal moving unit 113 and a rotating moving unit 115 such that the X-ray detector 105 has a variable unit. The apparatus further includes an automatic focusing and tracing unit 170 for moving in the Y _aft axis direction that is variably moved by 180. The auto focusing and tracing unit 170 includes a U-shaped Y _aft axial moving body 171 that is vertically installed to face the Z moving body 161 of the vertical moving unit 160. The configuration and operation of the automatic focusing and tracing unit 170 are the same as those described in detail in Korean Patent Application No. 10-2007-96918 of the applicant, and the detailed description thereof will be omitted.

Referring to FIG. 1, the controller 108 may include the driving motors 128, 143, 157, 163, and 176 of the positioning unit 111, the X-ray source 103, and the X-ray detector 105. By controlling the operation, it is controlled according to a tester's command input through the input unit 107 or a pre-programmed process. Here, the drive motors 128, 143, 157, 163, and 176 (the drive motor of the variable unit 180 is not shown) are Y-axis moving members of the horizontal moving part 113 of the positioning unit 111 ( 119 and the X-axis moving member 121, the square plate rotating body 153 of the rotary moving unit 115, the Z-axis moving body 161 of the vertical moving unit 160, the automatic focusing and tracing unit 170 The Y _aft axial moving object 171 and the holder bracket 184 of the variable unit 180 are respectively driven.

The controller 108 may be configured as a personal computer (PC) having an input unit 107 including a keyboard 107a and a mouse 107b.

In addition, according to the present invention it is possible to move the display on the display unit 109 at a constant speed irrespective of the geometric magnification (X) of the X-ray inspection apparatus 100, the inspection precision and efficiency In order to increase, the controller 108 controls the positioning unit 111 to displace the position of the test printed circuit board 104 based on the _pixel displacement speed V _pixel of the image displayed on the display unit 109. do.

In more detail, when the controller 108 moves the supporter 117 for supporting the printed circuit board 104 in the X-axis and / or Y-axis direction by the horizontal moving unit 113, the supporter 117 ) Is moved by the internal computing unit to the first linear movement speed (V _support ) (mm / sec) calculated according to the following equation (1). To control.

V _support (mm / sec) = V ' _pixel (pixel / sec) * D _pixel (mm / pixel) ------------- (1)

At this time, V ' _pixel (pixel / sec) is a value of the pixel displacement speed of the image displayed on the display unit 109 when the support 117 is moved in the X and Y axis directions by the horizontal moving unit 113. The pre-inspection inspector, in advance, enters into the controller 108 an appropriate value via the keyboard 107a and / or the mouse 107b.

D _pixel (mm / pixel) is a physical distance of one pixel of an image and can be calculated by the following equation (2).

D _pixel (mm / pixel) = D / total number of pixels

              = D / (X * X '* X "* cximage) -------------- (2)

Here, D is the size (mm) of the image displayed on the display unit 109,

X is the geometric magnification of the X-ray inspection apparatus 100,

X 'is the magnification of the image multiplier or flat panel detector 169 of the X-ray detector 105,

X "is the magnification of the CCD camera 172 of the X-ray detector 105,

cximage is the resolution (pixels) of the CCD camera 172.

In this case, X may be calculated as TD / TT, X 'is DO / DI, and X ″ is D / C.

Here, the TD is the focusing spot S where the X-ray collides with a target (not shown) in the X-ray tube of the X-ray source 103 and the plate detector 169 of the X-ray detector 105. Distance (mm) between

TT is the distance between the focusing spot (S) and the printed circuit board 104 to be inspected (mm),

DO is the length (mm) of the output surface of the plate detector 169 of the X-ray detector 105,

DI is the length (mm) of the input surface of the plate detector 169 of the X-ray detector 105,

C is the field of view (FOV) of the CCD camera 172 (mm).

Therefore, when the inspector inputs the pixel displacement velocity (V ' _pixel ) (pixel / sec) of the image displayed on the display unit 109 before the inspection through the input unit 107 to a value suitable for inspection, the background art will be described. As briefly mentioned above, even if the support 117 for supporting the printed circuit board 104 is moved in the Z-axis direction by the vertical moving unit 160, the controller 108 changes the magnification (X = TD / TT). ) Calculates the first linear movement speed (V _support ) (mm / sec) according to the above equation (1) through the internal calculation unit and accordingly drives the drive motors 128, and / or 143 of the horizontal movement unit 113. To control.

As a result, in the conventional case, even if the support 117 is moved in the Z-axis direction by the vertical moving unit 160 to change the magnification (X = TD / TT), the support 117 is at the same speed as before. At high magnifications where the value of D _pixel (mm / pixel) is small, the pixel displacement velocity (V _pixel ) becomes small, so that the image displayed on the display unit 109 moves more slowly than before, and D _pixel (mm / pixel) In the low magnification having a large value of), the pixel displacement velocity (V _pixel ) is increased so that the image displayed on the display unit 109 moves faster than before, and the inspector needs to reset the movement speed of the support 117. Although the speed and efficiency are reduced, according to the present invention, the inspector pre-sets the pixel displacement velocity (V ' _pixel ) (pixel / sec) of the image displayed on the display unit 109 before the inspection to a value suitable for inspection. Accordingly controller (108) ) Automatically calculates the first linear travel speed (V _support ) (mm / sec) as a value that is increased at low magnification and decreases at high magnification to drive the driving motors 128 and / or 143 of the horizontal moving part 113. When controlling the, the image displayed on the display unit 109 is displayed at a constant speed on the display unit 109 regardless of the magnification X.

As a result, as in the conventional inspection apparatus, the support 117 is moved in the Z-axis direction by the vertical moving unit 160 so that the first image of the image displayed on the display unit 109 whenever the magnification X changes. In order to adjust the linear movement speed, there is no inconvenience for the inspector to input the movement speed of the support 117 back to the controller 108 accordingly, thereby improving inspection accuracy and efficiency.

In addition, the controller 108 has the horizontal moving part 113, the rotating moving part 115, and the vertical moving part 160 with the second linear moving speed V ' _support calculated by the following equation (3) (mm / The driving motor 176 of the auto focusing and tracing unit 170 may be controlled to move to sec.

2nd linear travel speed (V ' _support ) (mm / sec) = V " _pixel (pixel / sec) * D _pixel (mm / pixel) ------------------ -(3)

Herein, the V ″ _pixel (pixel / sec) is a display unit 109 when the horizontal moving unit 113, the rotating moving unit 115, and the vertical moving unit 160 are moved by the automatic focusing and tracing unit 170. Is a pixel displacement velocity value of the image displayed on the controller, which is previously input to the controller 108 through the keyboard 107a and / or the mouse 107b by the pre-inspection inspector. V " _support (mm / sec) Is preferably set equal to V ' _support (mm / sec), but the present invention is not limited thereto and may be set differently.

In addition, the input unit 107 of the controller 108 may further include a positioning unit 111, a variable unit 180, and a joystick input unit 107c which finely and continuously controls the automatic focusing and tracing unit 170. Can be.

The joystick input unit 107c has a predetermined time, for example, to control the horizontal moving unit 113, the rotating moving unit 115, the vertical moving unit 160, and the variable unit 180 of the positioning unit 111, respectively. It is composed of a plurality of joysticks or buttons that continuously transmit the movement command in the operated direction to the controller 108 each time 0.01sec is operated.

When controlling each of the horizontal moving unit 113, the rotating moving unit 115, and the vertical moving unit 160 using the joystick input unit 107c, the controller 108 is horizontally moved from the joystick input unit 107c. The support 117 for supporting the printed circuit board 104 when the moving parts of the eastern part 113, the rotating moving part 115, and the vertical moving part 160 are continuously received in advance for each moving command. The driving motor 128 of the horizontal moving part 113, the rotating moving part 115, and the vertical moving part 160 to move according to the same set amount of correction, for example, a distance of several mm or an angle of several minutes. 143, 157, 163.

However, when controlling the variable unit 180 using the joystick input unit 107c, the controller 108 receives the X-ray detector when a movement command to the variable unit 108 is continuously received from the joystick input unit 107c. While controlling the variable unit 108 to move the 105 according to the same correction amount (mm) preset for each movement command, the support 117 for supporting the printed circuit board 104 is changed. For each movement instruction to the unit 108, the fourth direction, which is the movement direction of the X-ray detector 105, is substantially the same as the Y _aft axis direction according to the different first variation correction amount D _aft (mm). The driving motor 176 of the auto focusing and tracing unit 170 is controlled to move in the Y-axis direction. Here, the reason for controlling the first variation correction amount _Daft (mm) differently for each movement command for the variable unit 170 is that the previous movement command for the variable unit 170 is illustrated in FIG. 3A. The tilt angle (θ _offset ) of the X-ray detector 105 moved according to the state and the tilt angle (θ _offset ) of the X-ray detector 105 to be moved according to the next movement command for the variable unit 170 are the same. The first variation correction amount DP ' _aft or DP " moved by a previously generated movement command in order for the printed circuit board 104, particularly the inspection target portion, to be positioned on the X-ray axis of the X-ray detector 105 in FIG. _aft) (mm) first fluctuation correction amount (DP _"aft or D _aft) (mm) must move by the movement command generated after more is because the larger. As a result, the printed circuit board 104 supported by the support 117 is variable by moving to a different first variation correction amount _Daft (mm) different from the previous for each movement command to the variable unit 180. It is positioned on the X-ray axis of the X-ray detector 105 regardless of the tilt angle of the X-ray detector 105 which is variablely moved by the unit 180.

At this time, it is preferable that the first variation correction amount _Daft (mm) to be moved by one shift command is calculated by the following equation (4).

D _aft (mm) = {correction amount when the image detector 105 moves from 0 degree to the tilt angle (θ _current + θ _offset ) from the _current tilt angle (θ _current ) to the next tilt angle (θ _offset ) DF _aft ) _-correction amount DP _aft when the image detector 105 is moved from 0 degrees to the current tilt angle θ _current }

= {T _cent D * TT sin (θ _current + θ _offset )} / {TT _cent + T _cent D cos (θ _current +

θ _offset )}-{T _cent D * TT sin (θ _current )} / {TT _cent + T _cent D cos (θ _current )} --- (4)

Here, TT is the distance (mm) between the printed circuit board 104 in the focus spot (S) of the target of the x-ray source 103

T _cent D is the distance (mm) from the tilt center O of the X-ray detector 105 to the X-ray detector 105,

TT _cent is the distance (mm) from the focusing spot S of the target of the X-ray source 103 to the tilt center O,

θ _current is the current tilt angle of the X-ray detector 105 which is variably shifted with respect to the tilt center (0),

[theta] _offset is the tilt angle of the X-ray detector 105 which is variably moved with respect to the tilt center O by one movement command to the variable unit 180.

In the above, when controlling the variable unit 180 using the joystick input unit 107c, the controller 108 controls the auto focusing and tracing unit 170 to support the printed circuit board 104. ) Is illustrated and described as being moved according to the first variation correction amount _Daft, but the present invention is not limited thereto. That is, since the horizontal moving part 113 also moves the support tool 117 for supporting the printed circuit board 104 in the Y axis direction which is almost the same as the Y _aft axis direction, which is the moving direction of the X-ray detector 105. The controller 108 may move the supporter 117 according to the first variation correction amount _Daft by controlling the horizontal moving unit 113 instead of the automatic focusing and tracing unit 170.

In addition, after the X-ray detector 105 is moved by the variable unit 180 at a predetermined tilt angle, the vertical moving unit 160 is controlled by using the joystick input unit 107c to support the printed circuit board 104. When the supporting tool 117 is continuously moved in the Z-axis direction, the printed circuit board 104 supported by the supporting tool 117 is moved regardless of the position in the Z-axis direction moved by the vertical moving part 160. In order to be positioned on the X-ray axis of the X-ray detector 105, the controller 108 continuously receives a movement command to the vertical moving unit 160 from the joystick input unit 107c as shown in FIG. 3B. a holder (117) when a vertical is for each move command for the ET 160 is a second change correction amount (D _'aft) (mm) in accordance with X-ray moving direction of Y _aft axis of the detector 105 Drive motor 176 of automatic focusing and tracing unit 170 to move in the Y-axis direction substantially the same as the direction ).

At this time, the second change correction amount (D _'aft) (mm) is preferably calculated from the following equation (5).

D ' _aft (mm) = ± (Z _offset * T _cent D sin (θ ' _current ) / (TT _cent + T _cent D cos (θ ' _current )｝ --- (5)

Here, Z _offset is the Z-axis movement distance (mm) of the printed circuit board 104 to be moved by one movement command with respect to the vertical movement unit 160,

θ ' _current is the tilt angle of the X-ray detector 105 which is variably shifted with respect to the tilt center O when the printed circuit board 104 starts to move in the Z-axis direction.

In Equation (5), ± represents a direction in which the supporter 117 is moved in the Y-axis direction substantially the same as the Y _aft axis direction, that is, the direction in which the drive motor 176 of the auto focusing and tracing unit 170 rotates ( Clockwise (CW) or counterclockwise (CCW)).

In the above description, after the X-ray detector 105 is moved by the variable unit 180 to a predetermined tilt angle θ ' _current , the joystick input unit 107c is used to control the vertical moving unit 160 to print the circuit. When the substrate 104 is continuously moved in the Z-axis direction, the controller 108 controls the auto focusing and tracing unit 170 so that the support tool 117 supporting the printed circuit board 104 may have a second variation correction amount. Although it illustrated and demonstrated as moving according to (D' _{aft )} , this invention is not limited to this. That is, since the horizontal moving unit 113 can also move the support 117 in the Y-axis direction which is almost the same as the Y _aft axis direction, which is the moving direction of the X-ray detector 105, the controller 108 is used for automatic focusing and instead of tracing the horizontal portion 170 can be moved along the region (117) not to control the east (160) with a second fluctuation correction amount (D _'aft).

In addition, the controller 108 is printed by the display unit 109 when the printed circuit board 104 is rotated at a predetermined angle by the rotary mover 115 and then moved by the horizontal mover 113. The image of the circuit board 104 may be controlled to move based on the coordinates of the x 'axis direction x' and / or the y 'axis direction y' of the display unit 109.

In more detail, the support 117 for supporting the printed circuit board 104 by the rotary mover 115 is rotated by a predetermined angle, and then the X-axis direction X or Y by the horizontal mover 113. When moved in the axial direction (Y), the image of the printed circuit board 104 displayed through the display unit 109 is shown in the arrow direction (X or Y), as shown by dashed lines in FIGS. 4A and 5A. Move. However, in this case, the coordinate axis in the X-axis direction X or the Y-axis direction Y in which the printed circuit board 104 moves is left or right or front and rear that the inspector normally expects to move through the screen of the display unit 109. Direction, ie, the coordinate axis in the x'-axis direction x 'or y'-axis direction y' of the display unit 109. Therefore, as mentioned in the description of the background art, in order for the inspector to move the printed circuit board 104 to a specific inspection position as intended, the inspector rotates the horizontal moving part 113 by the rotating moving part 115. It is necessary to intentionally remember one rotation angle so as not to forget the moving direction of the current horizontal moving part 113. However, when the printed circuit board 104 is frequently rotated to inspect the printed circuit board 104 at various angles, it is difficult for the inspector to remember the rotation angle of the horizontal moving part 113 rotated. If the inspector does not remember the rotation angle of the horizontal moving unit 113, the inspector searches the rotation angle input to the controller 108 again, or moves the printed circuit board 104 back, forth, left, and right. As a result, there is a hassle of checking the moving direction of the horizontal moving part 113.

In order to prevent such a problem, according to the present invention, the controller 108 is rotated back and forth or left and right by the horizontal moving part 113 after the printed circuit board 104 is rotated by a predetermined angle by the rotating moving part 115. When moving to, the image of the printed circuit board 104 displayed through the display unit 109 is controlled to move in the x 'axis direction and the y' axis direction coordinate reference of the display unit 109 screen.

That is, the controller 108 rotates the printed circuit board 104 by a predetermined angle and then moves the printed circuit board 104 to the x'-axis direction and y'-axis of the screen of the display unit 109 by the keyboard 107a. When the x'-axis movement amount (mm) (XD ') for moving on the basis of the direction coordinates is input, the x'-axis movement amount (mm) (XD') is decomposed into the X-axis and Y-axis direction components and the first X-axis Calculate the direction conversion movement amount XD _X and the first Y-axis direction conversion movement amount YD _X (mm), and accordingly, move the horizontal moving portion (H) to move the support 117 supporting the printed circuit board 104. The drive motor 128 and / or 143 of the 113 is controlled.

At this time, as shown in Figure 4b, the x'-axis movement amount (mm) (XD ') is the first X-axis direction conversion movement amount (XD _X ) and the first Y-axis direction conversion movement amount (YD) according to the addition law of the vector _{Since X} is equal to the vector sum of mm, the first X-axis direction shift amount XD _X and the first Y-axis direction shift amount YD _X (mm) are calculated by the following equations (6) and (7). Can be.

XD _X (mm) = XD '* cosδ ------------------- (6)

YD _X (mm) = XD '* sinδ -------------------- (7)

Here, δ is the angle between the X axis direction axis of the horizontal moving unit 113 and the x 'axis direction axis of the display unit 109 after the printed circuit board 104 rotates.

Similarly, when the x'axial movement amount mm (XD ') is continuously input by the joystick input unit 107c after the printed circuit board 104 is rotated by a predetermined angle, the controller 108 generates a movement command. The first X-axis direction X conversion movement amount XDx and the first Y-axis direction conversion movement amount YDx (mm) are calculated by the above equations (6) and (7), and the printed circuit board 104 is The supporting support 117 is moved accordingly.

In addition, the controller 108 rotates the printed circuit board 104 by a predetermined angle and moves the printed circuit board 104 to the x'-axis direction and y'-axis of the screen of the display unit 109 by the keyboard 107a. When the y'-axis movement amount (mm) (YD ') for moving in the direction coordinate direction is input, the y'-axis movement amount (mm) (YD') is decomposed into the X-axis and Y-axis direction components, and the second X-axis The horizontal movement unit 113 calculates the direction conversion movement amount XDy and the second Y-axis direction conversion movement amount YDy (mm), thereby moving the support tool 117 supporting the printed circuit board 104. To control the driving motors 128 and / or 143.

At this time, as shown in FIG. 5B, the y'-axis movement amount mm (YD ') is the second X-axis direction conversion movement amount XDy and the second Y-axis direction movement movement amount YDy according to the vector addition law. Since it is equal to the vector sum of (mm), the second X-axis direction shift amount XDy and the second Y-axis direction shift amount YDy (mm) may be calculated by the following equations (8) and (9).

XD _Y (mm) = YD '* sinδ' ------------------ (8)

YD _Y (mm) = YD '* cosδ' ------------------- (9)

Here, δ 'is the angle between the Y axis direction axis of the horizontal moving unit 113 and the y' axis direction axis of the display unit 109 after the printed circuit board 104 rotates.

Similarly, if the y 'axial movement amount mm (YD') is continuously input by the joystick input unit 107c after the printed circuit board 104 is rotated by a predetermined angle, the controller 108 generates a movement command. The second X-axis direction shift amount XDy and the second Y-axis direction shift amount YDy (mm) are calculated by the above equations (8) and (9) for each time, and the printed circuit board 104 is supported. Move Earth 117 accordingly.

For example, after the printed circuit board 104 is rotated 45 degrees or 225 degrees, the x 'axial movement amount (mm) (XD') or y 'axial movement amount (mm) (YD') is applied to the keyboard 107a. When input by + 10mm, the controller 108 may determine an angle δ or a horizontal moving part 113 between the X axis direction (X) coordinate axis of the horizontal moving part 113 and the x 'axis direction coordinate axis of the display unit 109. The angle δ 'between the Y axis direction Y coordinate axis of the display unit and the y' axis direction coordinate axis of the display unit 109 is 45 degrees, and the first X axis direction conversion movement amount XD _X and the first Y axis direction conversion The shift amount YD _X (mm) or the shift amount XDy in the second X-axis direction and the shift amount YDy in the second Y-axis direction Y are given by the formulas (6), (7) or (8), (9), respectively. ) To 10 * cos 45 ° mm and 10 * sin 45 ° mm, or 10 * sin 45 ° mm and 10 * cos 45 ° mm, and the printed circuit board 104 is moved accordingly. As a result, the image of the printed circuit board 104 is 10 * cos 45 ° mm and 10 * sin 45 ° mm, or 10 * sin 45 ° mm, respectively, along the X axis direction (X) and Y axis direction (Y) coordinate axes. And 10 * cos 45 ° mm is displayed on the display unit 109.

Here, although the x'-axis or y'-axis movement amount (mm) (XD 'or YD') is illustrated as being input in units of distance (mm), the present invention is not limited thereto, but is input in units of speed instead of distance. Of course it can be.

The display unit 109 displays an image signal output from the X-ray detector 105 under the control of the controller 108 and may be configured as a monitor.

As described above, the X-ray inspection apparatus 100 according to the present invention has a controller displacement of the pixel displacement rate of the image displayed on the display unit 109 of the position of the printed circuit board 104 to be inspected. Since the positioning unit 111 is controlled to be displaced relative to the (V _pixel ), the image of the printed circuit board 104 can be moved at a constant speed regardless of the magnification during the inspection, and thus the printed circuit board 104 It is possible to improve the inspection precision and efficiency of the inspection target part such as the soldering part of the electronic chip.

In addition, the X-ray inspection apparatus 100 of the present invention drives the horizontal moving unit 113, the vertical moving unit 160, the rotary moving unit 115, the variable unit 180, etc. of the positioning unit 111. By providing an input unit 107 including a joystick input unit 107c for finely and continuously controlling the motors 128, 143, 157, and 163, the horizontal moving unit 113, the vertical moving unit 160, and the rotating moving unit are provided. The variable unit 180 may be controlled in a real-time movement manner, thereby improving inspection efficiency of the printed circuit board 104.

In addition, in the X-ray inspection apparatus 100 of the present invention, when the variable unit 180 is controlled by using the joystick input unit 107c, the controller 108 may control the automatic focusing and tracing unit 170 or the horizontal moving unit ( 113 to control the printed circuit board 104 in accordance with the movement direction of the X-ray detector 105 according to a different first variation correction amount _Daft (mm) for each movement command to the variable unit 180. It is configured to automatically move in about the same Y axis direction. Accordingly, the printed circuit board 104 may be automatically positioned on the X-ray axis of the X-ray detector 105 regardless of the tilt angle of the X-ray detector 105 which is variably moved by the variable unit 180. Accordingly, the inspection efficiency of the printed circuit board 104 may be improved.

In addition, the X-ray inspection apparatus 100 of the present invention, when the printed circuit board 104 is rotated by the rotary mover 115, and then moved back and forth or left and right by the horizontal mover 113, the controller ( 108 controls the horizontal moving unit 113 so that the image of the printed circuit board 104 displayed through the display unit 109 is based on the coordinates of the screen of the display unit 109, that is, x'axis direction and / or y '. It may be configured to move in the axial direction. Therefore, when the printed circuit board 104 is moved to a specific position after the printed circuit board 104 is rotated, the inspector moves the printed circuit board 104 to the display unit regardless of the rotation angle of the horizontal moving unit 113. 109) Since only the coordinates of the screen are moved, the position tracking and movement of the printed circuit board 104 can be easily performed, and thus the inspection efficiency of the printed circuit board 104 can be improved.

Hereinafter, using the X-ray inspection apparatus 100 according to the present invention configured as described above, any coordinate point of the inspection object, for example, the defect of the inspection target portion, such as the soldering portion of the electronic chip of the printed circuit board 104 An X-ray inspection method for inspecting whether or not will be described in detail with reference to FIG. 6.

First, the inspector uses the keyboard 107a and the mouse 107b of the input unit 107 to check the type and model of the inspection target printed circuit board 108, the coordinates of the inspection target site such as the soldering unit, and the image information acquisition unit. Initialization process of inputting basic information to the controller 108 such as setting position coordinates of the ray detector 105 and the pixel displacement velocity (V _pixel ; V ′ _pixel , V ″ _pixel ) of the image displayed on the display unit 109. Perform (S1).

Subsequently, under the control of the controller 108, the inspection target printed circuit board 104 is supported by the transfer unit, such as a conveyor belt (not shown) connected to the cabinet 101, of the positioning unit 111 inside the cabinet 101. 117 is supplied to the inspection position above (S2).

Thereafter, the horizontal moving part 113 and the vertical moving part 160 of the positioning unit 111 rotate the inspection target part of the printed circuit board 104 by a command signal inputted and output to the controller 108 in advance. The printed circuit board 104 is moved back and forth, left and right and up and down to be positioned at the center of rotation of the eastern part 115 and the focusing position between the X-ray source 103 and the X-ray detector 105 (S3). In this case, the controller 108 calculates the first linear movement speed V _support based on the _pixel displacement speed V ′ _pixel of the image displayed on the display unit 108 previously input through the internal calculator, and accordingly, The horizontal moving unit 113 is controlled.

At this time, if the horizontal moving unit 113 and / or the vertical moving unit 160 is controlled by the joystick input unit 107c without being controlled by the input value, the controller 108 is horizontally moved from the joystick input unit 107c. When the moving commands for the eastern side 113 and the vertical moving unit 160 are continuously received, the horizontal moving unit 113 and the vertical moving unit 160 have the same correction amount (mm) preset for each moving command, and / Alternatively, the horizontal moving part 113 and / or the vertical moving part 160 are controlled to move according to the first linear moving speed V _support corresponding thereto.

Subsequently, when inspecting the inspection target site by comparing image information obtained at various rotation angles with respect to the inspection target site of the printed circuit board 104 (S4), the controller 108 prints through the rotational moving unit 115. The inspection target portion of the circuit board 104 is rotated at a predetermined angle (S5). At this time, the controller 108 controls the rotation moving unit 115 according to the rotation speed value previously input through the keyboard 107a and the mouse 107b of the input unit 107. Also, in this case, when the rotation moving unit 115 is not controlled by the input value and is controlled through the joystick input unit 107c, the controller 108 moves a command from the joystick input unit 107c to the rotation moving unit 115. When the continuous movement is received, the rotation movement unit 115 is controlled to rotate according to the rotation speed of the same correction amount (mm) preset for each movement command.

In addition, when the inspection target region is inspected by comparing three-dimensional image information obtained at various imaging angles with respect to the inspection target region of the printed circuit board 104 (S6), the controller 107 may perform the X-ray detector 105. The target position of the input X-ray detector 105 and the target position of the input X-ray detector 105 so as to take a predetermined imaging angle with respect to the inspection target portion of the printed circuit board 104 located at the center of rotation of the rotary mover 115 and the predetermined focusing position. The X-ray detector 105 and the Y _aft axis are controlled by controlling the automatic focusing and tracing unit 170 of the variable unit 180 and the positioning unit 111 according to the movement target position of the printed circuit board 104. The direction moving body 171 is moved (S7). In this case, the controller 108 calculates the second linear movement speed V _support based on the _pixel displacement speed V ″ _pixel of the image displayed on the display unit 109 previously input through the internal calculator, and accordingly, The automatic focusing and tracing unit 170 is controlled.

Also, in this case, when the variable unit 180 is controlled by the joystick input unit 107c without being controlled by the set program or input value, the controller 108 may control the variable unit 180 from the joystick input unit 107c. When the movement command is continuously received, the printed circuit board 104 is controlled while controlling the variable unit 180 to move the X-ray detector 105 according to the same correction amount (mm) preset for each movement command. Y _aft , which is the direction of movement of the X-ray detector 105, according to a different first variation correction amount D _aft (mm) for each movement command to the variable unit 190. The automatic focusing and tracing unit 170 is controlled to move in the Y-axis direction which is almost the same as the axial direction.

In addition, after the printed circuit board 104 reaches the target position of the input X-ray detector 105 and the movement target position of the printed circuit board 104 accordingly, the vertical moving unit is moved by using the joystick input unit 107c. When controlling the 160 to move the printed circuit board 104 in the Z-axis direction, the controller 108 receives the printed circuit when a movement command to the vertical moving unit 160 is continuously received from the joystick input unit 107c. substrate 104, the vertical is in accordance with a second variation correction amount (D _'aft) (mm) for each move command for the ET 160 X-almost the ray traveling direction of Y _aft axis of the detector 105 The automatic focusing and tracing unit 170 is controlled to move in the same Y-axis direction.

In addition, after the printed circuit board 104 is rotated by the rotation moving unit 115, the printed circuit board 104 is moved to the x 'axis direction or the y' axis direction coordinate reference of the display unit 109 screen. When the x'-axis movement amount (mm) (XD ') and / or the y'-axis movement amount (mm) (YD') is input, the controller 108 may determine the first X-axis direction movement amount (XD _X ) and 1 Y-axis direction shift amount YD _X (mm), and / or second X-axis direction shift amount XD _X and second Y-axis direction shift amount YD _Y (mm) are calculated and printed accordingly. The horizontal moving unit 113 is controlled to move the circuit board 104.

As such, while the printed circuit board 104 moves in the front, rear, left, and right directions, and / or in the Y _aft axis direction, the controller 108 operates the X-ray source 103 to operate the printed circuit board 104. X-ray is irradiated to the X-ray detector, and the X-ray detector 105 controls the X-ray detector 105 to capture and output the image projected through the printed circuit board 104, and then the display unit 109 Control the display unit 109 to display the output image information (S8).

Thereafter, the inspector inspects whether the inspection target portion of the printed circuit board 104 is defective through the image information displayed through the display unit 109 (S9).

Subsequently, when inspecting by resetting the position of the inspection site to inspect the inspection target site by comparing the image information obtained at different positions, different rotation angles and different imaging angles with respect to the inspection target site of the printed circuit board 104 (S10), the controller 108, the positioning unit 111, the variable unit 180, the X-ray source 103, the X-ray detector 105 and the display to repeat the process of step S9 to step S3 The unit 109 is controlled. As a result, three-dimensional image information photographed from various directions and positions of the same inspection target part may be obtained, and the inspection process by mutual comparison may be performed.

In the above, certain preferred embodiments of the present invention have been illustrated and described. However, the present invention is not limited to the above-described embodiments, and any person having ordinary skill in the art to which the present invention pertains without departing from the spirit and spirit of the present invention as claimed in the claims may have various modifications and Modifications may be made.

1 is a block diagram showing an x-ray inspection apparatus as an embodiment of a defect inspection apparatus according to the present invention;

2A to 2C show a positioning unit applied to the x-ray inspection apparatus shown in FIG. 1,

3A and 3B are views for explaining an operation when controlling the positioning unit of the X-ray inspection apparatus shown in FIG. 1 by using a joystick input unit;

4A to 5B are views for explaining an operation of controlling the positioning unit of the X-ray inspection apparatus shown in FIG. 1 based on the coordinates of the x 'axis direction and the y' axis direction of the display unit screen;

FIG. 6 is a flowchart illustrating a control method of the x-ray inspection apparatus of FIG. 1.

* Description of the symbols for the main parts of the drawings *

100: x-ray inspection device 101: cabinet

103: x-ray source 105: image detector

107: input unit 107c: joystick input unit

108: controller 109: display unit

111; Positioning unit 113: horizontal moving part

115: rotation moving part 160: vertical moving part

170: automatic focusing and tracing unit 180: variable unit

Claims (45)

A horizontal moving unit for moving the inspection object in a first direction located on the same horizontal plane and in a second direction perpendicular to the first direction, and a vertical movement for moving the inspection object in a third direction perpendicular to the first and second directions A positioning unit having at least one of the eastern portions, the positioning unit changing the position of the inspection object; A light source for irradiating light to the inspection object; An image detector for detecting an image projected when the light source emits light onto the inspection object; A display unit which displays an image detected by the image detector; And And a controller for controlling the positioning unit to displace the position of the inspection object based on the _pixel displacement speed (V _pixel ) of the image displayed on the display unit. The method of claim 1, wherein the controller moves the inspection object at the first linear movement speed (V _support ) (mm / sec) calculated by the following equation when the inspection object is moved in the first direction or the second direction. The defect inspection apparatus, characterized in that for controlling the horizontal moving unit to move. V _support (mm / sec) = V ' _pixel (pixel / sec) * D _pixel (mm / pixel) Here, the V ' _pixel (pixel / sec) is input to the controller in advance, the pixel displacement rate value of the image displayed on the display when the inspection object is moved in the first direction or the second direction, D _pixel (mm / pixel) is the physical distance of one pixel. The defect inspection apparatus according to claim 2, wherein the D _pixel (mm / pixel) is calculated by the following equation. D _pixel (mm / pixel) = D / (X * X '* X "* cximage) Here, D is the size (mm) of the image displayed on the display unit, X is the geometric magnification of the defect inspection apparatus, X 'is the magnification of the image multiplier or flat panel detector of the image detector, X "is the magnification of the camera of the image detector, cximage is the resolution of the camera in pixels. The apparatus of claim 3, wherein X is TD / TT, X 'is DO / DI, and X ″ is D / C. Here, TD is the distance (mm) between the focus spot of the target of the light source and the image detector, TT is the distance between the focusing spot and the inspection object (mm), DO is the length (mm) of the output surface of the image multiplier or flat panel detector, DI is the length (mm) of the input surface of the image multiplier or flat panel detector, C is the field of view (FOV) of the camera (mm), 5. The method of claim 4, The positioning unit further includes a rotation moving part for rotating the inspection object, wherein the rotation movement part is disposed below the horizontal moving part to rotate the horizontal moving part to rotate the inspection object. Defective inspection device. The method of claim 5, And a variable unit which supports the image detector and variably moves the image detector in the fourth direction in an arc shape with respect to the tilt center to have a plurality of incident angles with respect to any coordinate point of the inspection object. The positioning unit may be configured to move at least two of the horizontal moving part, the rotating moving part, and the vertical moving part in the fourth direction in which the image detector is variably moved. AFT) defect inspection apparatus further comprises. The method of claim 6, wherein the controller is a second linear movement speed (V ' _support ) (mm / sec) of at least two of the horizontal moving portion, the rotary moving portion, and the vertical moving portion calculated by the following equation And control the automatic focusing and tracing unit to move to. V ' _support (mm / sec) = V " _pixel (pixel / sec) * D _pixel (mm / pixel) Herein, a V ″ _pixel (pixel / sec) is input to the controller in advance, and the display is performed when the at least two of the horizontal moving part, the rotating moving part, and the vertical moving part of the positioning unit are moved. Pixel displacement velocity value of the image displayed on the negative. The apparatus of claim 6, wherein the controller further comprises a joystick input unit for finely and continuously controlling the positioning unit, the variable unit, and the automatic focusing and tracing unit. 10. The controller according to claim 8, wherein the joystick input unit respectively supplies a movement command in an operated direction to control the horizontal moving unit, the rotating moving unit, and the vertical moving unit and the variable unit of the positioning unit. The defect inspection apparatus comprising one of a plurality of joysticks and a plurality of buttons to transmit continuously.        The controller according to claim 8, wherein when the joystick input unit is used to control each of the horizontal moving unit, the rotary moving unit, and the vertical moving unit of the positioning unit, the controller is configured to shift the horizontal from the joystick input unit. The horizontal moving part and the rotation are adapted to move the inspection object according to the same correction amount for each of the moving commands when the moving commands for the eastern part, the rotating moving part, and the vertical moving part are continuously received. The eastern part, and the defect inspection apparatus, characterized in that for controlling the vertical movement. 10. The apparatus of claim 8, wherein, when controlling the variable unit using the joystick input unit, the controller sends the image detector to each of the image shift commands when a movement command for the variable unit is continuously received from the joystick input unit. A first variation that varies with the tilt angle of the image detector variablely moved for each of the movement commands for the variable unit, while controlling the variable unit to move according to the same correction amount with respect to the variable unit. And one of the automatic focusing and tracing unit and the horizontal moving unit to move in the fourth direction which is the same as the moving direction of the image detector according to the correction amount _Daft . 12. The defect inspection apparatus according to claim 11, wherein the first variation correction amount _Daft is calculated by the following equation. D _aft = {T _cent D * TT sin (θ _current + θ _offset )} / {TT _cent + T _cent D cos (θ _current + θ _offset )}-{T _cent D * TT sin (θ _current )} / {TT _cent + T _cent D cos (θ _current )} Here, TT is the distance between the focus spot of the target of the light source and the inspection object T _cent D is the distance between the tilt center of the image detector and the image detector, TT _cent is the distance from the focusing spot to the tilt center, θ _current is the tilt angle of the image detector variable shifted with respect to the tilt center to date, [theta] _offset is the tilt angle of the image detector variable shifted with respect to the tilt center by one shift instruction of each shift instruction with respect to the variable unit. The controller of claim 8, wherein when the image detector is variably moved by the variable unit at a predetermined angle with respect to the tilt center, the controller is configured to control the vertical moving unit using the joystick input unit. according to a second variation correction amount (D _'aft) in which the perpendicular is the inspection object to the vertical when the movement command for the East be successively received in response to the third direction, the moving distance for each movement command on the Eastern the And controlling one of the automatic focusing and tracing unit and the horizontal moving unit to move in the fourth direction which is the same as the moving direction of the image detector. The defect inspection apparatus according to claim 13, wherein the second variation correction amount D ' _aft is calculated by the following equation. D ' _aft = ± (Z _offset * T _cent D sin (θ' _current ) / (TT _cent + T _cent D cos (θ ' _current )｝ Here, Z _offset is a third direction moving distance of the inspection object to be moved by one movement command of each movement command with respect to the vertical movement unit, θ ' _current is the tilt angle of the image detector variable shifted with respect to the tilt center when the test object starts to move in the third direction, T _cent D is the distance between the tilt center of the image detector and the image detector, TT _cent is the distance from the focus spot of the target of the image detector to the tilt center. The display unit screen of claim 5, wherein the controller is configured to display an image of the test object displayed through the display unit when the test object is moved by the horizontal moving unit after the test object is rotated by the rotation moving unit by a predetermined angle. The defect inspection apparatus, characterized in that for controlling the horizontal moving unit to move in the first and second direction coordinate reference. The method of claim 15, wherein the controller inputs a first direction movement amount (mm) XD 'for moving the inspection object to the first and second direction coordinates of the display unit screen by an input means from the outside. The first direction shift amount XD _X and the second direction shift amount mm XD ′ of the display unit screen reference are decomposed into a first direction component and a second direction component of the horizontal shifter reference. Calculating a conversion movement amount (YD _X ) (mm), and thereby controls the horizontal moving unit to move the inspection object. The defect inspection apparatus according to claim 16, wherein the first conversion movement amount XD _X and the second conversion movement amount YD _X (mm) are respectively calculated by the following equations. XD _X (mm) = XD '* cosδ YD _X (mm) = XD '* sinδ Here, δ is an angle between the first direction coordinate axis of the horizontal moving unit and the first direction coordinate axis of the display unit after the inspection object is rotated. The method of claim 16, wherein the controller inputs a second direction movement amount (mm) YD 'for moving the inspection object to the first and second direction coordinates of the display unit screen by an input means from the outside. Is converted into a first direction component and a second direction component of the horizontal moving unit reference to the third conversion movement amount XD _Y (mm) And a fourth conversion movement amount (YD _Y ) (mm), and thereby control the horizontal moving unit to move the inspection object. 19. The defect inspection apparatus according to claim 18, wherein the third conversion movement amount XD _Y and the fourth conversion movement amount YD _Y (mm) are respectively calculated by the following equations. XD _Y (mm) = YD '* sinδ' YD _Y (mm) = YD '* cosδ' Here, δ 'is an angle between the second direction coordinate axis of the horizontal moving unit and the second direction coordinate axis of the display unit after the inspection object is rotated. The method of claim 6, The inspection object includes a printed circuit board, The first, second, third and fourth directions include X, Y, Z and Y axes, respectively. And the light source comprises an x-ray source for generating x-rays. delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete

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