JPH11186487A - IC lead frame automatic inspection system and operation method thereof - Google Patents

Abstract

(57) [Summary] (with correction) [PROBLEMS] An automatic IC lead frame inspection system using a computer, a CCD camera, and video processing software. A system for inspecting four items of lead spacing, pad movement, tape position, and punching defect. By designing an image acquisition part and an inspection part with independent threads, the system can continue even while performing the inspection. To improve the overall performance of the camera. In particular, the spacing inspection uses a high-magnification dedicated camera, and uses the sub-pixel method to stably maintain the accuracy of about 1/3 of one pixel. The tape inspection uses the correlation between the positions of the tape boundaries. An algorithm that can reduce and expand the polygon corresponding to the tape form so that it can be inspected for any tape shape has been developed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic inspection system for an IC lead frame for automatically inspecting the shape of an IC lead frame by using a video processing technique and a method of operating the same. Computer and CCD for shape inspection of IC lead frame
The present invention relates to a high-speed and automatic inspection system using a camera and video processing software, and an operation method thereof.

[0002]

2. Description of the Related Art Generally, parts inspection processes in factories have been carried out by human eyes. However, the demand for manufacturing speed and product quality has increased, and the necessity of batch inspection (100% inspection) of entire products has been increasing. IC due to rapid market growth
The number has increased significantly in the inspection of defects of components or circuit boards (PCBs) in the manufacturing process.

In particular, the role of the lead frame in the IC manufacturing process is very important. After 100% inspection in the manufacturing process of the lead frame, visual and mechanical inspection is performed in the incoming process at the IC assembly factory. It must go through many stages of inspection process such as Dimension Check.

[0004] Also, IC lead frames are as diverse as ICs, and their types and forms are very complicated. Various automatic inspections of a large number of lead frames are recognized as indispensable elements for producing high quality ICs. In the situation.

[0005]

Accordingly, the above-described IC
Since the object of the component or the circuit board is extremely small and precise, there are the following problems in making a judgment with human vision, so that the automation of the inspection is further required.

[0006] 1) The inspection standard changes depending on individual differences, or even with the same person over time or feelings of the day. Therefore, there may be a problem in trust with consumers as a cause of instability in product quality.

2) The minimum size that can be visually recognized is about 0.1
Since it is up to 1 mm, a microscope is required for inspection of extremely small defects, which lowers inspection efficiency and increases inspector fatigue.

[0008] 3) 0.2 to 0.
Since it takes four seconds, there is a problem that a high-speed inspection suitable for a manufacturing speed is impossible.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in order to solve the above-mentioned various problems, and a computer, a CCD camera, and an image processing apparatus have been used to inspect the shape of an IC lead frame which has been dependent on the naked eye of an inspector. The purpose of the present invention is to provide an automatic IC lead frame inspection system for automating and speeding up an inspection process by using a lead frame defect automatic interpretation technology and a lead frame automatic transfer device in combination, and a method of operating the system. is there.

[0010]

In order to achieve the above object, an automatic IC lead frame inspection system according to the present invention comprises:
An image capturing unit that includes one or more CCD cameras and one or more illumination control units and captures an image of the IC lead frame that has reached the inspection position; and a lead frame sensing unit that detects the lead frame that has reached the inspection position. One or more lead frame sensors for generating signals, an image processing unit for acquiring and processing an image captured by the image capturing unit,
An automatic transfer device that automatically transfers the lead frame to be inspected to the inspection position one by one, and controls the entire operation of the inspection system, receives and inspects the image from the image processing unit, and inspects the lead frame of the inspected image. And a main control unit for determining a defective product.

Further, in the automatic IC lead frame inspection system according to the present invention, the video processing unit receives the video of the camera into the A video buffer using two A and B video buffers, and then performs main control from the A video buffer. While moving the video data to the memory of the computer, the other B video buffer receives video from the camera following the other B video buffer.
The process of replacing the role of the B video buffer is repeatedly performed.

Further, the IC lead frame automatic inspection system of the present invention can indicate the operation command of the IC lead frame automatic read interval visual inspection apparatus with a pointer indicator, and can determine whether the inspection object is good or defective and the size of the position. It is characterized by having a GUI (Graphic User Interface) for visually outputting the result.

Further, an automatic IC lead frame inspection system according to the present invention includes one or more CCD cameras and one or more illumination control units, and an image photographing unit for photographing an image of the IC lead frame reaching the inspection position. A lead frame sensor for detecting a lead frame reaching the inspection position and generating a lead frame detection signal; an image processing unit for acquiring and processing an image captured by the image capturing unit; An automatic transfer device that automatically transfers the lead frames to be inspected one by one to the inspection position, and controls the entire operation of the inspection system, receives an image from the image processing unit,
A main control unit for inspecting and determining non-defective and defective lead frames of the inspected video, wherein the automatic transfer device stacks and supplies a lead frame to be inspected, and a product input stacker. Loading device that sucks the products supplied from the product one by one and loads them to the product transfer section, a product transfer device that transfers the loaded products to the inspection position, and a two-sheet detection sensor that detects two product suctions And a product classification device that classifies products inspected according to the inspection results, a defective product stacker that stacks defective products, and a non-defective product,
It is characterized by comprising a take-out device for taking out, an operation operation panel for setting and displaying required operation conditions of the automatic transfer device, and a control device for controlling all operations of the automatic transfer device.

The method for operating an automatic IC lead frame inspection system according to the present invention includes an image acquisition process for acquiring an image at high speed, a reference coordinate system setting inspection process using a pad, and a reference coordinate system by searching for a pad position. Inspection process for lead spacing after setting, pad movement inspection process for inspecting pad movement, tape shape inspection process for inspecting tape shape, punching result inspection process, and inspection result statistical processing And a process.

Further, in the method of operating an automatic IC lead frame inspection system according to the present invention, the image acquisition step is performed in such a manner that processing of an image photographed by a ping-pong algorithm can be performed simultaneously with photographing of an image subsequent to the image. It is characterized by.

In the method of operating an automatic IC lead frame inspection system according to the present invention, the reference coordinate system is set so as to search for a boundary point of a pad on two vertical and horizontal lines (Lh, Lv) passing through the center of an image. From this boundary point, a rectangle indicating the approximate pad position is determined, and a straight line that divides the rectangle vertically and horizontally by n is determined. A total of 4n boundary points that meet the pad boundary along this straight line ,
The method is characterized in that a straight line closest to the n boundary points for each side of the pad is obtained, and the center and the inclination of the pad are calculated using the straight line.

In the method of operating an automatic IC lead frame inspection system according to the present invention, the lead spacing searches for a pad position, uses a center of the pad as an origin, and uses a coordinate system rotated by an inclination as a reference coordinate system (xy). And is used for inspection.

Further, in the method of operating the automatic IC lead frame inspection system according to the present invention, the pad movement is inspected by measuring a length between a dam bar and one side of a pad corresponding to the dam bar.

In the method of operating an automatic IC lead frame inspection system according to the present invention, the tape shape may be such that when a reference coordinate system is set, CAD data of a lead frame tape boundary line is converted into a reference coordinate system. It is characterized in that the tape boundary converted on the coordinate system is enlarged and reduced by a given tolerance, and an area where the boundary of the tape to be inspected is placed is set.

Further, in the method for operating an automatic IC lead frame inspection system according to the present invention, the enlarged boundary is located outside the tape, and the image corresponding to the position of the boundary has a number of bright pixels equal to or more than a predetermined value. Must be equal to or greater than a certain ratio, and the reduced boundary line is located inside the tape, and the image corresponding to the position of the boundary line must have a certain number of dark pixels that are equal to or less than a certain brightness if the number of dark pixels is equal to or greater than a certain ratio. It is characterized by not becoming.

In the method of operating an automatic IC lead frame inspection system according to the present invention, the method of enlarging / reducing the tape boundary line uses a method of enlarging and reducing an arbitrary polygon.

In the method of operating an automatic IC lead frame inspection system according to the present invention, the enlargement and reduction of the polygon may be
After finding the vertex having the highest y value from the vertices of the polygon, the positions of two sides having this vertex in common are investigated, and the enlarged or reduced position of the side between this vertex and the next vertex is determined. Are moved one by one, and taking into account the position of the two sides that share the moved vertices and the position of the last enlarged or reduced side, determine the enlarged or reduced position of the side between the current vertex and the next vertex. It is characterized by deciding.

In the method for operating an automatic IC lead frame inspection system according to the present invention, the defect of the punching may be performed by searching a punched area at a specified punching position.
The inspection is characterized by using geometric features such as the area of the region, the length of the boundary line, the density, and the like.

In the method of operating an automatic IC lead frame inspection system according to the present invention, the video acquisition means and the inspection means are designed with two independent threads, and the video acquisition means uses two or more video buffers. In addition, even if the inspection is in progress, one or more images can be acquired in advance to increase the overall inspection speed.

In the method for operating an automatic IC lead frame inspection system according to the present invention, the image acquisition thread starts transferring the lead frame (S10), and determines whether a sensor detects the transferred component. If it is detected, it moves to the next step, otherwise, it repeats this process (S11), and it acquires the image (S1).
2) and determine whether there is an acquired image, and if there is no acquired image, return to the previous step and repeat the above process;
Otherwise, the step of moving to the next step (S13), the step of stopping the transfer (S14), and judging whether or not there is an image obtained again, return to the first transfer start step if there is no obtained image. Otherwise, this step is repeated (S15).

In the method for operating an automatic IC lead frame inspection system according to the present invention, the inspection thread determines whether the image is a lead frame image to be inspected, and moves to the next stage if the image is a lead frame image. Otherwise, a step of repeatedly performing this process (S20), determining whether the pad is a detection pad, and if it is a detection pad, moving to the next step; otherwise, returning to the first step (S21),
Step of judging whether there is a defect by inspecting the tape (S22)
If there is a defect, it sends a defect signal and returns to the first stage,
If there is no defect, the step (S23) of performing a process of outputting a passing signal and returning to the first step is performed.

Further, the system of the present invention is a system for inspecting four items of a lead spacing, a pad shift, a tape position, and a punching defect. In order to improve the inspection speed and to provide a flexible inspection environment, the video acquisition part and the inspection part were designed with independent threads, and WindowsNT was used as an operating system in consideration of system stability and compatibility.

Also, by designing this system with two independent threads, it is possible to acquire images continuously while performing the inspection, thereby improving the overall performance.

In particular, since the spacing inspection requires very high precision, a dedicated camera with a high magnification is used, and the precision of about 1/3 of one pixel is stably maintained by using a sub-pixel method. I was able to.

The tape inspection is performed by using the correlation between the positions of the tape boundary lines, and an algorithm has been developed that can reduce and enlarge the polygon corresponding to the tape shape so that the tape shape can be inspected. .

As a result of experiments on an actual lead frame using such an inspection method, it can be confirmed that the system is a high-speed, high-precision inspection system capable of inspecting about five lead frame units per second. .

[0032]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is an overall hardware configuration diagram showing an IC lead frame automatic inspection system according to the present invention. As shown in the figure, the main control unit (Host PC) 1
00, image processing unit (Image Board) 200, signal input / output unit
(DIO Board) Two Cs with 300, 640 x 480 resolution
CD camera 400, two illumination control units (Strobe Controll)
er) 500 and a transfer device 600.

According to the above configuration, the video processing unit 200
Has a 3 Mbyte frame memory, is logically composed of 12 frames, and can store up to 12 images. When the lead frame 700 is transferred by the transfer device 600 and the sensor 601 detects this, the sensor signal is transmitted to the image processing unit 2 via the signal input / output unit 300.
00 is input. At this time, the main control computer unit 1
When 00 confirms the sensor signal, it drives the illumination control unit 500, drives the CCD camera 400 in synchronization with this, and inputs an image to the memory of the main control computer unit 100 via the image processing unit 200. At the rear end of the transfer device 600, a stacker that classifies the inspected lead frame 700 as normal or defective according to the inspection result.
Is installed. This transfer device 600 will be described later in detail with reference to FIG.

The inspection software of the present system includes an image acquisition part using a ping-pong algorithm, a pad movement inspection part, a subpixel length measurement part for lead spacing inspection, a tape inspection part, and a punching inspection. Part, and a simple test result statistical processing part.

The GUI (Graphic User Interface) is Visua
l C ++ 4.2 Compiler and MFC (Microsoft Foundation Cl
(ass) library.

In particular, the existing inspection system has a drawback that a general user requires a long time and effort to set up an inspection environment. In order to improve this point, necessary inspection data is mainly stored in a design drawing. By using the above data and automatically converting the inspection data for changes in the inspection environment, such as a change in camera distance, the inspection can be performed, thereby significantly reducing user intervention due to changes in the inspection environment. Was.

FIG. 2 is an explanatory diagram of image acquisition using the ping-pong algorithm method. As shown in the figure, the ping-pong algorithm for acquiring an image at high speed is as follows. First, an image of the camera 400 is input to and received from the A image buffer 800 using two A and B image buffers 800 and 801. While moving the video data from the buffer 800 to the memory of the main control computer unit 100, the video from the camera 400 is received following the other B video buffer 801 and the roles of the buffers A and B are switched to the next video input. The structure is such that an image is received while the above process is repeated. That is, since a previously input image can be transmitted to the main control computer 100 at the same time as receiving an image from the camera 400, the time required for inputting the image can be minimized.

FIG. 3 is an overall flowchart showing an image acquisition thread and an inspection thread. In order to inspect 10 or more images per second at high speed, it is necessary to reduce the image acquisition time required for about 30 msec to the maximum. In this inspection system,
The video acquisition thread and the inspection thread were designed with two independent threads, and the video processing unit was designed to receive the video continuously even while the inspection by the main control computer was in progress.

When the image acquisition thread method is started according to the drawing, the transfer of the lead frame is started (S1).
0), it is determined whether the sensor has detected the transferred component. If detected, the process moves to the next step S12, and if not, the process is repeated (S11). The image acquisition lighting control is performed (S12), and it is determined whether the buffer is empty. If the buffer is empty, the process returns to S11 to repeat the above-described process. Otherwise, the process moves to the next S14 (S13).
The transfer is stopped (S14), and it is determined again whether the buffer is empty. If the buffer is empty, the process proceeds to S10, and if not, the process is repeated (S15).

When the tape inspection thread method is started, it is determined whether or not the image is a buffer image. If the image is a buffer image, the process moves to S21. If not, the process is repeated (S20). The pad detection is determined, and if it is the pad detection, the process moves to S22; otherwise, the process moves to S20 (S21). Next, a tape inspection is performed to determine whether there is a defect (S22).
After step 5), the process proceeds to step S20, and if there is no defect, the process of sending the signal to step S20 via the non-defective signal (S24) is performed (S20).
23).

FIG. 4 is an explanatory diagram relating to a method of setting a reference coordinate system using a pad. The position of the pad is searched in two stages. That is, first, a boundary point of a pad on two vertical and horizontal lines (Lh, Lv) passing through the center of an image is searched, and a rectangle representing a rough pad position is obtained from the boundary point.

Next, a straight line that divides the rectangle into n parts in the vertical and horizontal directions is determined, and all 4n boundary points meeting the boundary of the pad along this straight line are determined.

After obtaining a straight line that is most approximate to the n boundary points for each side of the pad, the center and the inclination of the pad are calculated using the straight line.

A coordinate system rotated by the inclination with the center of the pad as the origin is set as a reference coordinate system (xy), and all coordinates used for inspection are converted into this reference coordinate system.

FIG. 5 shows a lead spacing inspection screen after the reference coordinate system has been set by searching for the position of the pad. FIG. 5A shows an example of an inspection model created by inspection software executed by a computer. FIG. 5B shows a screen in which an inspection is in progress by inspection software executed on a computer.

The lead spacing inspection requires high precision. In the case of a 160-pin product, the area of interest is a lead frame area of about 2 × 2 cm, and in the case of a 640 × 480 camera, the resolution is 0.03 mm / pixel. Get.

Since a reliable lead spacing inspection is difficult with this degree of precision, the precision is reduced to about 1/3 pixel (0.01 pixel) by applying a sub-pixel measurement algorithm.
mm).

In this system, the algorithm proposed by Tabatabai was used. This method is suitable for a high-speed and high-precision lead spacing inspection because the length measurement value is insensitive to the length of the pixel row and the amount of calculation is considerably reduced as compared with other methods.

FIG. 6 is an explanatory diagram of a method for measuring the distance between the pad and the dam bar. As shown in the figure, the pad movement inspection is performed by measuring the length between one side of the dam bar and the corresponding pad.

In this inspection system, in order to detect the position of the dam bar, by dividing the candidate region of the dam bar position into a number of sub-regions, it is possible to accurately inspect the inclination of the lead frame. .

FIG. 7 is an illustrative view showing a method of inspecting the shape of the tape. As shown in the figure, when the reference coordinate system is set, the CAD data of the border line of the lead frame tape is converted into the reference coordinate system (thick rectangle in FIG. 7).

Next, the tape boundary converted on the reference coordinate system is enlarged and reduced by the given tolerance (dotted line in FIG. 7), and the boundary of the tape to be inspected (gray area in FIG. 7) is changed. Set the area to be placed.

Since the enlarged boundary line should be located outside the tape, the image corresponding to the boundary line position must have a certain ratio of bright pixels of a certain value or more and a certain ratio or more. Since the boundary line should be located inside the tape, the image corresponding to the boundary line position must have a certain ratio or more of the number of dark pixels having a certain brightness or less.

FIG. 8 is a view showing various types of tapes to be used in the inspection system of the present invention. The tapes attached to the lead frames have various types.

Therefore, in order for the tape inspection method using the boundary line to be applied to all types of tapes, a method of expanding and reducing a general polygon is required.

FIG. 9 is a diagram showing a polygon reduction method used as a method for inspecting the shape of a tape. As shown in the figure, in order to enlarge or reduce the polygon, first, a vertex having the highest y value among the vertices of the polygon is obtained, and the positions of two sides having this vertex in common are checked. Determine the enlarged or reduced position of the edge between the vertex and the next vertex.

Next, the vertices are moved one by one, and in consideration of the positions of the two sides that share the moved vertices and the position of the immediately expanded or reduced side, the side of the side between the current vertex and the next vertex is considered. Determine the enlarged or reduced position.

Inspection of a punching defect is performed by searching for a punched area at a specified punching position and then using geometric features such as the area of the area, the length of the boundary line, and the density. I do.

FIG. 10 is a view showing an IC lead frame automatic transfer device 600 for automatic inspection.

In order to automatically perform the inspection of the IC lead frame, loading of a product, loading, removal of a slip sheet, detection of two sheets, feeding, sorting and loading of defective and non-defective products, slip sheet Insertion or the like is configured so that the computer signal and the feeding device signal match each other, and in order to ensure the accuracy of the measurement of the product, continuous feeding or step feeding can be selected according to the characteristics of the product, and the characteristics of the product , Two or three cameras can be installed so that the photographing unit differs depending on the shape.

Since units of the same shape are continuously arranged in one strip due to the characteristics of the lead frame, the photographing error generated at the time of repetitive photographing is corrected by computer software. During continuous feeding, the error range is minimized by using a precision sensor in the regular holes of the product. During step feeding, the pitch input is set on the LCD (liquid crystal display) to minimize the error range. PLC (60
Controlled by 2).

As shown in FIG.
Reference numeral 0 denotes a product loading stacker 610 for stacking and supplying a lead frame to be inspected, a product loading device 620 for sucking products supplied from the product loading stacker one by one and loading the products into a product transfer unit, and a loaded product. Transfer device 63 for transferring the product to the inspection position
0, two-sheet detection sensor 64 that senses two product suctions
0, a product classifying device 650 for classifying products inspected according to the inspection result, a defective product stacker 660 for stacking defective products, an unloading device 670 for stacking and unloading non-defective products, and required operating conditions of the automatic transfer device. It comprises a driving operation panel 680 for setting and displaying, and a control device 690 for controlling all operations of the automatic transfer device 600.

FIGS. 1 and 10 show the operation according to the configuration of the present apparatus.
This will be described with reference to FIG. 1. Product stacker device (STACKER DEVICE) Stacks products to be inspected. The loading magazines where strip products are mounted in bundle units are installed at four locations. These installation locations are configured at two locations on both sides centering on the feeding section. When there is a slip sheet between the products, the products are stacked in two places, two places are used as a place for taking out the slip sheet, and four places are used for a product having no slip sheet.

The height and width of the product stacker can be adjusted according to the product size. The height is automatically adjusted up and down by ELEVATOR according to the amount of the product when the stacker senses the product. If there is no product, the stacker magazine moves down and there is no product. Is turned on, a buzzer sounds, and the control LCD indicates that there is no product.

2. LOADING DEVIC
E) [Slip-sheet removal and product pickup loading (PICKU
P LOADING)] Product pick-up is performed by air vacuum suction pad,
The loading device simultaneously performs slip sheet removal and product loading at two locations.

In the case of a product pick-up error (PICKUP MISS), a message is displayed on an alarm lamp and an alarm BALL & LCD after three consecutive executions.

The speed can be improved by changing the loading method of the products with and without the slip sheet between the products.

The loading device drive system is driven by the use of a robot arm, and can change the pickup point. The pickup loading device can perform loading and pickup at two places at the same time, or one place can be used to remove a slip sheet and one place. Can perform pickup and loading.

Further, other machines (M / C) (TAPING, CUTTI
NG, STAMPING) to switch from loading to feeding.

3. Two product detection sensor When two products are stacked during product loading,
Check the product with two detection sensors and discard the product.
Perform re-pickup and load so that two cards do not come in and out.

4. Feeding Method In the feeding method, the initial entry is performed by conveyor feeding, and then the stopper is driven. Then, the roller can be driven in two modes, STEP TO STEP and continuous roll feeding, by a roll driving method using a sub motor.

5. Inspection part sensor configuration 1) Continuous inspection A sensor that determines the product position for inspection detects the pilot hole of the product, and if one unit has more than one hole, recognizes only one hole in the pitch. Control LCD with system setting mode to get
To enter. Up, down, left and right adjustments are convenient so that the position of the sensor can be easily determined.

2) STEP TO STEP inspection Enter the distance from the stopper to the # 1 sensor, and
Enter the EP pitch and the number of units in the strip.

After moving by the input distance from the stopper to the # 1 sensor, it moves to the STEP pitch, inspects the number of units, and after the inspection is completed, is transferred to continuous feeding.

The transmission of the sensor signal to the image processing unit is transmitted to a computer via a micro process or a PLC, and is transmitted to a camera and a strobe (STROBE) via the PLC. When the signal of the sensor is transmitted through the PLC, the strobe and the camera are respectively operated to photograph the shape of the product, and the photographed product shows the shape on the computer monitor while passing the pass and fail signals through the PLC. Send out.

6. Defective product processing and stacking stacker 1) A reject signal and a pass signal are sent from the computer 15 via the PLC, and the defect processing section receives a product arrival signal from a sensor, and passes the product if passed.
If it is defective, the stopper is operated to stop the product, and the shutter of the guide rail is opened to stack the defective stacker.

2) When the product is fully stacked in the magazine of the defective stacker, the lamp blinks and the bell rings while the sensor detects, indicating that the defective product is full (FULL) on the control LCD, and The stacker magazine will automatically descend and take out the product.

At this time, if a defective product occurs, the spare stacker magazine is turned on and when the defective stacker magazine is stacked and comes to the position of the defective stacker magazine, the spare stacker is turned off and running is performed in a normal state.

7. Passed product unloading device (insertion of slip-sheets and unloading of product pick-up) Products that have been judged and transferred as passed products are loaded by opening the shutter according to the equipment design and then bundled in the quantity set for the conveyor type. The product is picked up by an air vacuum suction pad and the product is picked up and taken out by stacking it in a product takeout magazine.

If it is necessary to insert a slip sheet between products, insertion can also be performed. Therefore, in order to evaluate the inspection performance of the IC lead frame automatic inspection system of the present invention, the 100-pin and 160-pin lead frame products were each reduced by about
The test was repeated with about 0 strips. This experiment first confirmed the stable implementation of the inspection software and hardware and the automatic transfer mechanism. The experiment was performed about 10 times, and was performed continuously for about 3 hours or more in one experiment. As a result, a relatively stable inspection was performed as a whole. The inspection speed was up to about 5 units (10 images) per second. The test product was once passed through inspection equipment to determine a defective or non-defective product, and a number of repetitive experiments were performed. As a result, about 2% different inspection performances were obtained.

The inspection precision can be measured down to a unit of 0.03 mm using a measurement method using sub-pixels.

[0082]

As described above, according to the automatic lead frame inspection system of the present invention and the operation method thereof,
The following effects are obtained.

That is, the shape inspection of the lead frame which has been performed by the inspector with the naked eye can be automated at a high speed.

Furthermore, the time required to modify the inspection specifications and inspection data, which required a long time of about 5 hours to 1 day each time the inspection object was replaced, is reduced to 30 minutes to 2 hours. Flexibility can be provided.

Further, since the lead frame automatic transfer device of the system of the present invention can be directly connected to the production equipment at the site, the produced lead frame is immediately transferred to the inspection equipment and inspected. This is a useful invention having such an effect that a transportation facility is not required.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an automatic lead frame inspection system of the present invention.

FIG. 2 is an explanatory diagram showing an image acquisition method using the ping-pong algorithm of the present invention.

FIG. 3 is an overall flowchart showing an image acquisition thread and an inspection thread of the present invention on Windows NT.

FIG. 4 is an explanatory diagram showing a method of setting a reference coordinate system using the pad of the present invention.

FIG. 5A is a view showing an example of creating an inspection model of inspection software executed by the computer of the present invention. (B) is an exemplary diagram showing a lead spacing inspection screen in which an inspection is being performed by inspection software executed by a computer.

FIG. 6 is an explanatory view showing a method for measuring a distance between a pad and a dam bar according to the present invention.

FIG. 7 is an explanatory view showing an example of the tape shape inspection method of the present invention.

FIG. 8 is a view showing various types of tapes targeted in the inspection system of the present invention.

FIG. 9 is a diagram showing a polygon reduction method used as a method for inspecting the shape of a tape according to the present invention.

FIG. 10 is a view showing an automatic lead frame transfer device for automatic inspection according to the present invention.

[Explanation of symbols]

 Reference Signs List 100 main control unit, main control computer unit 200 image processing unit 300 signal input / output unit 400 CCD camera 500 lighting control unit 501 lighting 600 transfer device, automatic transfer device 610 product loading stacker 620 product loading device 630 product transfer device 640 two-sheet detection Sensor 650 Product classification device 660 Defective product stacker 670 Product removal device 680 Operation operation panel 690 Control device 700 Lead frame, IC lead frame 800 Buffer, video buffer

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kim Hyun Jin 431-5 Gun-dong, Yuseong-gu, Daejeon, Republic of Korea (72) Inventor Wi Myung Ching South Korea Busan Haeundeg Banyo 1-Don 543-1 (72) Inventor Lizon Tech South Korea Busan Haeundeg Banyo 1-Don 1411-10 Modern Apartment 301-1005 (72) Inventor Hong Suk Dong South Korea Busan Bukguk Gupo-dong Modern apartment 102-203

Claims (17)

[Claims] 1. An image photographing unit comprising one or more CCD cameras and one or more lighting control units for photographing an image of an IC lead frame reaching an inspection position, and detecting a lead frame reaching the inspection position. One or more lead frame sensors that generate a lead frame sensing signal, an image processing unit that acquires and processes images captured by the image capturing unit, and a lead frame to be inspected is automatically located one by one at the inspection position. An automatic transfer device for transferring the inspection image to the main frame, and a main control unit that controls the overall operation of the inspection system, receives and inspects the image from the image processing unit, and determines a non-defective or defective lead frame of the inspected image. An automatic IC lead frame inspection system. 2. The video processing unit receives video of a camera in an A video buffer using two A and B video buffers and then transfers video data from the A video buffer to a memory of a main control computer. An image is received from the camera following the other B image buffer, and A,
2. The automatic IC lead frame inspection system according to claim 1, wherein the process of replacing the role of the B video buffer is repeatedly performed. 3. A GUI (Graphic User) that can instruct an operation command in the automatic visual inspection apparatus for lead interval of an IC lead frame with a pointer indicator and visually outputs good / bad and position size of an inspection object. 2. The automatic IC lead frame inspection system according to claim 1, further comprising an interface. 4. An image photographing unit comprising one or more CCD cameras and one or more illumination control units, for photographing an image of an IC lead frame reaching the inspection position, and detecting the lead frame reaching the inspection position. One or more lead frame sensors that generate a lead frame sensing signal, an image processing unit that acquires and processes images captured by the image capturing unit, And a main control unit that controls the overall operation of the inspection system, receives and inspects an image from the image processing unit, and determines a good or defective lead frame of the inspected image. The automatic transfer device includes a product input stacker for stacking and supplying a lead frame to be inspected, and a product supplied from the product input stacker. A product loading device that sucks and loads a product to a product transfer unit, a product transfer device that transfers the loaded product to an inspection position, a two-sheet detection sensor that senses two products being sucked, and an inspection result. A product classification device for classifying products, a defective product stacker for stacking defective products,
An IC lead comprising: an unloading device for stacking and unloading non-defective products; an operation operation panel for setting and displaying required operating conditions of the automatic transfer device; and a control device for controlling all operations of the automatic transfer device. Automatic frame inspection system. 5. An image acquisition process for acquiring an image at a high speed, a reference coordinate system setting inspection process using a pad, and a lead position inspection after a reference coordinate system is set by searching a pad position. A pad movement inspection process for inspecting the presence / absence of pad movement, a tape shape inspection process for inspecting a tape shape, a punching result inspection process, and an inspection result statistical processing process. Inspection system operation method. 6. The automatic lead frame as claimed in claim 5, wherein the image acquiring step performs a process on an image photographed by a ping-pong algorithm simultaneously with the photographing of a subsequent image. Inspection system operation method. 7. The reference coordinate system setting finds a boundary point of a pad on two vertical and horizontal lines (Lh, Lv) passing through the center of an image, and indicates a rough position of the pad from the boundary point. A rectangle is obtained, and a straight line that divides this rectangle into n parts in the vertical and horizontal directions is obtained. A total of 4n boundary points meeting the boundary of the pad along this straight line are obtained, and n boundary points for each side of the pad are obtained. 6. The method according to claim 5, wherein a straight line closest to the point is obtained, and the center and the inclination of the pad are calculated using the straight line. 8. In the lead spacing, a pad position is searched, a coordinate system rotated by a tilt is set as a reference coordinate system (xy) with the center of the pad as an origin, and this is used for inspection. The method for operating an automatic IC lead frame inspection system according to claim 5. 9. The IC lead frame automatic inspection system operation method according to claim 5, wherein the pad movement is inspected by measuring a length between a dam bar and one side of a pad corresponding to the dam bar. 10. The tape shape is such that when a reference coordinate system is set, CAD data of a lead frame tape boundary line is converted into a reference coordinate system, and the converted tape boundary line is given on the reference coordinate system. 6. The method according to claim 5, further comprising setting an area in which the boundary of the tape to be inspected is placed by enlarging and reducing by the tolerance. 11. The enlarged boundary is located outside the tape, and an image corresponding to the position of the boundary must be reduced in that the number of bright pixels having a certain value or more must be a certain ratio or more. 11. The IC lead according to claim 10, wherein the boundary line is located inside the tape, and an image corresponding to the position of the boundary line must have a number of dark pixels having a certain brightness or less and a certain ratio or more. Automatic frame inspection system operation method. 12. The method according to claim 10, wherein the method of enlarging / reducing the tape boundary line uses a method of enlarging and reducing an arbitrary polygon. 13. The enlargement and reduction of the polygon is performed by obtaining a vertex having the highest y value from the vertices of the polygon, and then examining the positions of two sides having the vertex in common. Determine the enlarged or reduced position of the side in between, move the vertices one by one, and consider the position of the two sides that share the moved vertex and the position of the immediately expanded or reduced side, and consider the current vertex 13. The method according to claim 12, wherein an enlarged or reduced position of a side between the next vertices is determined. 14. The punching defect is searched for a punched area at a specified punching position and inspected using geometric features such as the area of this area, the length of the boundary line, the density, and the like. I according to claim 5, characterized in that:
C lead frame automatic inspection system operation method. 15. The video acquisition means and the inspection means are designed in two independent threads, and the video acquisition means uses two or more video buffers, so that even if the inspection is in progress, one or more 6. The IC according to claim 5, wherein the whole inspection speed is increased by acquiring images in advance.
Operation method of lead frame automatic inspection system. 16. The image acquisition thread determines whether to start the transfer of the lead frame, determines whether a sensor detects the transferred component, and moves to the next step if detected, otherwise proceeds to the next step. Iteratively performing, acquiring an image, and determining whether there is an acquired image.If there is no acquired image, the process returns to the previous stage and repeats the above process. Otherwise, the process proceeds to the next stage. Moving, stopping the transfer, judging whether there is any reacquired image, returning to the initial transfer start stage if there is no acquired image, otherwise repeating the process. The method for operating an automatic IC lead frame inspection system according to claim 15, comprising: 17. The inspection thread determines whether the image is a lead frame image to be inspected, and if the image is a lead frame image, moves to the next step; otherwise, repeats this process, and Judge whether it is a pad,
If it is a detection pad, move to the next step, otherwise return to the first step, tape inspection to determine whether there is a defect, and if there is a defect, send a defect signal to the first step 16. The method according to claim 15, further comprising: performing a process of returning to the initial stage by outputting a passing signal if there is no defect.