KR20040044249A - Optical apparatus of vision system for testing in-circuit pcb - Google Patents

Abstract

PURPOSE: An optic device of a vision system for testing a PCB(Printed Circuit Board) is provided to photograph simultaneously both sides of the PCB by using one infrared camera or one high-resolution camera. CONSTITUTION: An optic device of a vision system for testing a PCB includes a both-sided rotary mirror unit(20) and a PCB fixing plate(30). The both-sided rotary mirror unit and the PCB fixing plate are installed in the inside of a chamber(10). A light absorption part(90) is installed on an inner wall of the chamber. The both-sided rotary mirror unit transmits an upper image and a lower image of a reflected subject to a lens of an infrared camera/high-resolution camera(40). The PCB fixing plate is used for applying the power and signals to the PCB. A first top reflector(13) and a first bottom reflector(11) are installed at a top part and a bottom part of the PCB fixing plate, respectively. A second top reflector(14) and a second bottom reflector(12) are installed at a top part and a bottom part of the both-sided rotary mirror unit, respectively.

Description

OPTICAL APPARATUS OF VISION SYSTEM FOR TESTING IN-CIRCUIT PCB}

The present invention is an optical device of a vision system for inspection of a component-mounted circuit board that can simultaneously photograph both sides of the component-mounted circuit board to be inspected as a single infrared camera or a high-resolution camera using a double-sided rotating device and a vertical reflector in the inspection chamber. In particular, since the vertical arrangement of the chamber space can be changed to a horizontal arrangement, it is possible to design a stable and space-reduced, as well as absorb vibrations during shooting, thereby improving productivity and reducing production costs by improving reliability. The present invention relates to an optical device of a vision system for inspecting component-mount circuit boards.

With the rapid development of semiconductor technology, integrated circuits have also been developed in various ways and applied to component mounting circuit boards. In order to inspect electronic components on the circuit board, expensive insert kit testers, X-ray equipment, flying equipment, and vision equipment are used. By the way, in the board test of a high density integrated circuit, since the measurement pad is difficult to install, it showed the limit to the reliability measurement of individual components.

Unlike the general measuring instrument that inspects a single electronic component, the insert kit tester inspects electronic components assembled on a component mounting circuit board automatically and removes the influence of peripheral components, thereby automatically inspecting defective items, contents, and defective positions. Is displayed on the monitor.

Since most of the current equipment is photographed on a subject, that is, a component mounting circuit board, almost all of the current component mounting circuit boards have parts mounted on both sides. In some cases, the mounting circuit board was repeatedly photographed up and down, or three cameras were installed at the top and the bottom of the chamber.

The camera method in the vision equipment is a conventional two-dimensional array CCD (Charge Coupled Device) method and a linear array CCD method that is currently in progress and showing a high resolution, and the camera device used here is an expensive infrared camera or Several high resolution cameras are installed.

However, what can come out as a problem when photographing a subject in a vision device as described above is a problem in which additional methods such as time or equipment remain in any way, and thus, there is a difficulty in lowering the cost of the equipment. . For this reason, low cost and simple optical device design have required a means for expecting such cost and space savings.

Accordingly, the present applicant is focused on the functional variety of the camera, and by supplementing and applying the problems of the conventional vision system, the optical system development and design so that the circuit board test of expensive and high-density integrated circuit can be performed more smoothly. Was done.

The present invention invented a novel optical device that is compatible with and accommodates both two-dimensional and linear array CCD methods in view of all the problems of the conventional vision system described above. In addition to the solution, the utilization can be applied according to the type of camera according to the type of utilization, which can reduce the additional cost of the system due to the change of the camera in the future and the productivity and the production cost according to the reduction of the test period. The object of the present invention is to provide an optical system of a vision system for inspecting a component-mounted circuit board which can be reduced.

1 is an installation perspective view showing an optical apparatus of a vision system for inspecting a component mounting circuit board according to an embodiment of the present invention;

2 is a detailed block diagram illustrating an optical device of a vision system for inspecting a component-mounted circuit board according to the present invention;

3 and 4 is a set-up flow and detailed view for explaining the operation of the optical device of the vision system for component mounting circuit board inspection of the present invention,

5 is a structural diagram showing in detail the double-sided rotary device shown in Figure 2,

6 is a block diagram illustrating the connection of a controller, computer and power supply.

* Explanation of symbols on the main parts of the drawings

10: chamber 20: double-sided rotating light device

30: circuit board holder 40: camera

50: controller 60: power supply

70: computer 90: light absorber

In order to achieve the above object, the present invention provides a light absorbing body (90) which prevents diffuse reflection and direct incidence of various light in the chamber (10) on the inner wall. A double-sided rotating device 20 for entering the lens of the camera / high resolution camera 40 and a circuit board fixing stand 30 for applying power and other signals to the component mounting circuit board are provided, respectively. The upper and lower reflecting mirrors 13 and 11 are inclined upward and downward, and the upper and lower reflectors 14 and 12 are inclined, respectively. It features.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is an installation perspective view showing an optical device of a vision system for inspecting a component-mounted circuit board according to an embodiment of the present invention. The present invention is a double-sided rotating mirror device 20 and an upper and lower reflector within the inspection chamber 10. 11-14) and an infrared camera 40 or an optical device of a vision system for inspection of a component-mounted circuit board capable of simultaneously photographing both sides of a component-mounted circuit board to be inspected as a high resolution camera. 10) By changing the vertical arrangement of the space into a horizontal arrangement, not only stable and space-saving design is possible, but also absorbing vibrations during shooting, it is possible to improve productivity and reduce production costs by improving reliability. have.

The chamber 10 is provided with a light absorber 90 on the inner wall to prevent diffuse reflection and direct incidence of various lights including infrared rays so as to obtain an accurate image required for the camera 40 to be described later, and from the center to the outside One infrared camera 40 or a high resolution camera is installed, while a monitor 75, a keyboard 76, a controller 50, a power supply 60, and a computer 70 are respectively installed.

In the chamber 10, a double-sided rotating device 20 for injecting a reflected image of an upper or lower image of a subject into an external infrared camera / high resolution camera 40 and a power supply and other signals to a component mounting circuit board. Each of the circuit board fixing tables 30 to which the device is applied is provided. In addition, the chamber 10 is provided with a process line conveyor 15 in which the component mounting circuit board is arranged and moved so as to stop and move for a predetermined time at the position of the circuit board holder 30.

The upper and lower reflecting mirrors 13 and 11 inclined at a predetermined angle are provided above and below the circuit board fixing plate 30, respectively. The upper reflector 13 accurately illuminates the upper surface of the component mounting circuit board to be photographed in the center on the circuit board fixture 30 and transmits the light to the other upper reflector 14 located in front, and the lower reflector 11 is a circuit board fixture. Accurately illuminate the bottom of the component mounting circuit board on (30) and transfer it to another lower reflector (12) located in front of it.

In addition, the upper reflector 14 and the lower reflector 12 which are inclined at a predetermined angle are respectively provided above and below the double-sided rotating tilting device 20. Therefore, one infrared camera 40 is provided through the double-sided rotating mirror device 20 in which the upper surface of the component mounting circuit board from the upper reflector 14 and the lower surface of the component mounting circuit board from the lower reflector 12 operate. Or it enters into the lens of a high resolution camera.

2 is a detailed block diagram illustrating an optical device of a vision system for inspecting a component-mounted circuit board according to the present invention, and FIGS. 3 and 4 illustrate an optical device of the vision system for inspection of a component-mounted circuit board according to the present invention. Here's the setup flow and details.

In an operation method using a two-dimensional array CCD camera, which is one infrared camera 40 shown in FIG. 2, an opening is formed in the circuit board fixing stand 30 so that the component mounting circuit board 32 is mounted thereon. The power supply required for the component mounting circuit board 32 is input from the power supply 60 shown in Fig. 1, and the application of other necessary signals is input from the outside.

The circuit board holder 30 is a pin probe holder 35 under the board connector 33 of the lower holder 39 shown in FIG. 4 so that the component mounting circuit board 32 can be fixed and power and signals can be applied thereto. Pin probe 34 is provided, and the installation shape and arrangement of the component mounting circuit boards 32 to be tested are different. The upper fixing stand 38 is installed at both sides of the lower fixing stand 39, and the pin probe connecting wire 36 is connected under the pin probe 34.

Since the circuit board holder 30 shown in FIG. 2 having a different shape depending on the type of the component mounting circuit board 32 is located at the position of the board connector 33 positioned at the edge, the power supply as shown in FIG. And a highly conductive metal pin probe 34 capable of applying various signals are randomly contacted / disconnected. The main function here is to connect the power supply and input and output of the signal through the pin probe (34).

In addition, as shown in FIG. 3, the upper portion of the component mounting circuit board 32 may be a solenoid or pneumatic cylinder 37 at a suitable pressure to smoothly contact the pin probe 34. The component mounting circuit board 32 is pressurized to contact the pin probe 34 from above.

Meanwhile, the upper fixing stand 38 and the lower fixing stand 39 accurately fix the component mounting circuit board 32 of the circuit board fixing stand 30 as the size of the component mounting circuit board to be tested. The upper fixing stand 38 has an upper reflecting mirror 13 as its upper space, and the lower fixing stand 39 has a lower reflecting mirror 11 as its lower space. The upper fixing stand 38 is provided with a pneumatic cylinder 37.

The upper surface of the component mounting circuit board 32 prepared in the circuit board fixing plate 30 is first incident on the upper reflector 13 as an image and reflected by another upper reflector 14 as shown in FIG. 2. Subsequently, the top image of the component mounting circuit board 32 reflected by the double-sided rotary device 20 is photographed by the camera 40. After the photographing is performed, the double-sided rotating device 20 is rotated 90 degrees to prepare for photographing the bottom image of the next component mounting circuit board 32.

Subsequently, the bottom surface of the component mounting circuit board 32 is incident on the lower reflector 11 as an image and reflected by another lower reflector 12 as shown in FIG. 2, and is reflected through the double-sided rotating mirror device 20 therefrom. The bottom image of the component mounting circuit board 32 is captured by the camera 40. As the filming is performed, both parts of the component mounting circuit board 32 can be used as one infrared camera 40 or a general high-resolution camera as if two cameras were used at the same time as in the prior art, thereby reducing expensive camera equipment to one camera. There is an advantage.

FIG. 5 is a structural diagram showing the double-sided rotating device shown in FIG. 2 in detail. The operation method of one infrared camera 40 shown in FIG. 2 using a linear array CCD camera is a double-sided rotating device 20. ) Plays a very important role, so the camera 40 has no choice but to implement a horizontal or vertical image of one line. By using the double-sided rotating mirror device 20, a very large area can be photographed by a scanning technique.

In this method, since the position of the double-sided mirror 21 is changed according to the minute angle adjustment of the double-sided rotating mirror device 20, the image irradiated according to each position is incident on the camera 40 to obtain the whole image. It becomes possible. The double-sided mirror 21 is installed on the rotary plate 23 of the symmetrical position hole 24, the rotary plate 23 is driven by the step motor / sub-motor 25 while the lower position sensor 22 It is meant to pass.

The position sensor 22 in the double-sided rotating mirror device 20 determines the vertical initial position of the image. Of course, a position sensor 22 for adjusting the position, a step motor driver 52 shown in FIG. 6, and a logic circuit 58 for synchronizing shooting are required.

FIG. 6 is a block diagram showing the connection of the controller 50, the computer 70, and the power supply 60 shown in FIG. 1, and the double-sided rotary device 20 shown in FIG. By this, the computer 70 to which the monitor 75 and the keyboard 76 are connected is connected and installed, while the linear motor 41 and the camera 40 are also connected and installed. The computer 70 is connected to the controller 50, the power supply 60 and the camera 40 through RS-232C (56, 71-73), respectively, and through the grabber board (74) It is connected to the camera 40.

In the present invention, the double-sided rotary device 20 is connected to the step motor driver 52 of the controller 50 while the position sensor 22 is connected to the logic circuit 58. The logic circuit 58 is a step motor 80 and the position sensor 22 of the server motor 25 'is connected, the server motor driver 53, the linear motor driver 54, The microprocessor 55 and the reflector motor driver 57 are respectively connected. Then, the power supply 51 is connected to the camera 40 to supply the necessary power to operate.

The server motor driver 53 uses the server motor 25 ', the linear motor driver 54 uses the linear motor 41, the microprocessor 55 uses the RS-232C 56, the computer 70, The reflector motor driver 57 is connected to drive the step motor 80, respectively, and the camera 40 and the power supply 60 are connected to the computer 70, respectively.

The glass board 74 is an interface for converting a digital signal from the camera 40 to the computer 70. The computer 70 drives a signal required by a driver for arithmetic operations and other mechanical and mechanical driving devices. In particular, the computer 70 processes, stores, and stores the image signal obtained from the camera 40.

In addition, the power supply 60 supplies various voltages and currents, that is, the voltage, current, and power can be selected from the RS-232C 72 of the computer 70. Therefore, it is a device for supplying the power required for the component mounting circuit board required for the actual inspection, and has a built-in function that can protect the circuit, such as preventing the excessive current flow while performing the power on / off.

The step motor of the step motor / server motor 25 of the double-sided rotary device 20 can control the precise angle of the rotary plate 23 by controlling the motor by the pulsed motor drive. That is, it is a drive device that can accurately set the angle of the double-sided rotary device 20, the step motor may be configured as a general server motor 25 'in the case of a scan operation. In this case, the double-sided mirror 21 connected to the motor rotated at constant speed performs an optical function of transmitting a signal of an image according to each angle to the camera 40 from time to time.

The camera 40 acquires a vertical image signal, and the value of the position received from the position sensor 22 is a trigger signal for generating a vertical synchronization signal and a position value of the double-sided mirror 21 of the double-sided rotating mirror device 20. It is used to get The power supply 51 of the controller 50 supplies power required for the camera 40.

The step motor driver 52 driving the step motor / server motor 25 is a device that converts a pulse controlled by the microprocessor 55 into power capable of driving the step motor through the logic circuit 58. . The server motor driver 53 driving the general server motor 25 'converts a signal controlled from the microprocessor 55 into power capable of driving the server motor 25' through the logic circuit 58. Giving device.

The microprocessor 55 directly processes signals input from each motor and other sensors. The microprocessor 55 generates pulses of step motors in conjunction with the computer 70 and transmits various signals to the RS-233C (56, 71). Communicate with the computer 70 through the processing of the functional. RS-232C (56, 71-73) is a communication protocol performs a signal and interworking function of the microprocessor 55 and the computer 70. It is also responsible for the control of the camera 40 and the power supply 60.

The position sensor 22 of the double-sided rotating mirror device 20 is a photo interrupt that accurately grasps the position of the rotating plate 23 of the double-sided mirror 21 on which the symmetrical position holes 24 are installed. And a signal generator for synchronizing the video signal from the camera 40 with each other. The signals generated according to the position of the sensor are two kinds of position holes 24, in which the upper part and the lower part of the camera 40 are photographed.

The linear motor driver 54 which drives the linear motor 41 on which the camera 40 is placed is driven by a pulse controlled by the microprocessor 55 to drive the linear motor 41 through the logic circuit 58. Convert it. The linear motor 41 has a function of determining the photographing area of the camera 40 by the data commanded by the computer 70, and can adjust the size of the image formed according to the perspective of the camera 40.

Therefore, this position is stored in the computer 70, and when using the same component mounting circuit board 32, the data is retrieved from the computer 70 to drive the linear motor 41 to obtain the image of the same ratio have. The linear motor driver 54 for driving the linear motor 41 plays a role similar to the step motor driver 52 described above, and can move the camera 40 in a very fine motion.

On the other hand, the reflector motor driver 57 of the controller 50 is to drive the position of the upper and lower reflection mirror shown in Figure 2 with the step motor 80, which is a logic circuit (controlled by the signal from the microprocessor 55) 58) is a device that converts the server motor 80 into a power capable of driving. The reflector motor driver 57 uses an axis that simultaneously moves four reflectors to the same position. The step motor 80 is also provided with a position sensor.

The height of the reflector (11-14), that is, there is a function that can be changed up and down to adjust the size of the image, this function to adjust the size of the image, such as the linear motor 41 of the camera 40 Can be. At this time, the reflector position control motor 80 moves up and down and can be controlled by the motor control driver 57.

As described above, according to the present invention, a single infrared camera or a high resolution camera can simultaneously capture both sides of the component mounting circuit board to perform a function of two expensive cameras, and secure a little space in the chamber. Therefore, the 2D array camera or the linear array camera can be easily mounted and utilized as needed, so that the optical devices of component-mounted circuit boards and vision systems using high-definition resolution can be used as well as economic savings.

In addition, the present invention can obtain a higher resolution photographic image by fine angle adjustment of the double-sided rotating mirror device without the need for additional mechanism by the easy use of the linear array camera according to the scan format, such an optical system As a result, the value of the system is very high because it reduces the complexity and cost of the future.

Claims (6)

In the chamber 10 in which the light absorber 90 is installed on the inner wall to prevent diffuse reflection and direct incidence of various lights, the upper image or the lower image of the reflected subject is transferred to the lens of the external infrared camera / high resolution camera 40. A double-sided rotating mirror device 20 for incidence and a circuit board fixing stand 30 for applying power and other signals to the component mounting circuit board are respectively provided, and the upper reflecting mirror inclined upwards and downwards of the circuit board fixing stand 30. 13) and the lower reflector 11, the vision system for component mounting circuit board inspection, characterized in that the inclined upper reflector 14 and the lower reflector 12 are respectively installed above and below the double-sided rotary mirror device 20 Optics. The method of claim 1, An opening is formed in the circuit board holder 30 so that the component mounting circuit board 32 is mounted. The power supply required for the component mounting circuit board 32 is supplied from the power supply 60, and other necessary signals are applied. An optical device of a vision system for inspecting a component-mounted circuit board, which is input from the outside. The double-sided rotary device 20 is connected to the step motor driver 52 of the controller 50 while the position sensor 22 is connected to the logic circuit 58; The logic circuit 58 is a step motor 80 and the position sensor 22 of the server motor 25 'is connected, the server motor driver 53, the linear motor driver 54, A microprocessor 55 and a reflector motor driver 57 are respectively connected; The server motor driver 53 uses the server motor 25 ', the linear motor driver 54 uses the linear motor 41, the microprocessor 55 uses the RS-232C 56, the computer 70, Vision system for component mounting circuit board inspection, characterized in that the reflector motor driver 57 is connected to drive the step motor 80, respectively, the camera 40 and the power supply 60 are connected to the computer 70, respectively. Optics. The method of claim 3, wherein The position sensor 22 of the double-sided rotating mirror device 20 is a photo interrupt that accurately grasps the position of the rotating plate 23 of the double-sided mirror 21 on which the symmetrical position holes 24 are installed. And the video signal from the camera 40 are synchronized with each other, and the signals generated according to the position of the sensor are two kinds of position holes 24, wherein the upper part and the lower part of the camera 40 are determined. Optical system of vision system for circuit board inspection. The method of claim 3, wherein The power supply 51 of the controller 50 is connected to the camera 40 to supply the necessary power to operate the optical device of the vision system for component mounting circuit board inspection. The method of claim 3, wherein The linear motor 41 determines the photographing area of the camera 40 with data commanded from the computer 70, and adjusts the size of the image formed according to the perspective of the camera 40. Optical system of vision system for board inspection.