SL Introduction to Optical Inspection1

Introduction to Optical Inspection Helge Jordfald Sales & Marketing Manager Tordivel AS – Norway

SL Introduction to Optical Inspection3 Content Why Automated Optical Inspection? How does it work?

SL Introduction to Optical Inspection4 Why Automated Optical inspection? To improve production and reduce cost through: Quality Control Flaw detection Yield Management Factory Automation

SL Introduction to Optical Inspection5 Alternatives Manual Control Sample Control Mechanical Control Photo Sensor Control No Control

SL Introduction to Optical Inspection6 Manual versus Automated Manual Inspection –Varies over time and with different persons –Monotonous work Automated Optical Inspection –Fixed quality over time –High speed –Traceability and documentation

SL Introduction to Optical Inspection7 Quality Control Zero faults to customers –100% control instead of sample control –Objective and constant quality control Use Vision Control as sales argument

SL Introduction to Optical Inspection8 Flaw Detection Reduce added value to defective parts –Identify and remove products with flaw early in the production line –Use several inspection station –Reduce materiel consumption –Increase your production capacity

SL Introduction to Optical Inspection9 Yield Management Monitor changes in production performance Do corrections before the yield is reduced Real time statistics and trends

SL Introduction to Optical Inspection10 Flexible Automation Increase production efficiency and flexibility by: –Automatic guiding of robots for picking and packing products –Automatic product sorting and program selection Reduce inspection costs Improve Health, Environment and Safety –Automate heavy and monotonous manual job functions

SL Introduction to Optical Inspection11 How does it work? System components Resolution and tolerances Basic image processing techniques Magic?

SL Introduction to Optical Inspection12 Basic system Standard PC One or more cameras Illumination Mounting system and protection for light and cameras Communication interface to Control System

SL Introduction to Optical Inspection13 The Optical System Camera –CCD array, Line camera, Area camera –Analogue or Digital signal transmission Lenses –Adapted to the individual applications An Optical System –A picture of a physical area (FOV = Field Of View) –With a specified resolution –With a minimum of optical distortion (compromise)

SL Introduction to Optical Inspection14 Illumination The key to a good and reliable Vision system An increasing number of specialised lighting sources for different applications –Fiber, LED, Laser –On-Axis, Cloudy Day, Darkfield Selection of lighting source – a job for experts

SL Introduction to Optical Inspection15 Communication with the production line Logical –Trigger – Take image –Answer – Result Physical - Electrical –24 volt isolated –RS-232, Ethernet – tcp/ip Protocols to robot, PLC and web TDVCmdProtocol – RS TCP/IP OPC – ip – profibus (PLC and PC systems)

SL Introduction to Optical Inspection16 Graphical User Interface

SL Introduction to Optical Inspection17 Process insight

SL Introduction to Optical Inspection18 Documentation

SL Introduction to Optical Inspection19 Camera - Field of View Piksels in X direction Pixels in Y direction

SL Introduction to Optical Inspection20 Grey scale pictures Original Greyscale Pixel grid

SL Introduction to Optical Inspection21 Pixel resolution VGA Camera –640 x 480 pixels FOV: 5mm x 5mm –Resolution ca. 0,01mm FOV: 50mm x 50 mm –Resolution ca. 0,1mm FOV: 500mm x 500mm –Resolution ca. 1 mm High Res. Camera –1024 x 768 pixels FOW: 5mm x 5mm –Resolution ca. 0,005mm FOW: 50mm x 50 mm –Resolution ca. 0,05mm FOW: 500mm x 500mm –Resolution ca. 0,5 mm

SL Introduction to Optical Inspection22 Example - Pixel Resolution

SL Introduction to Optical Inspection23 Gauging Intensity level variations along the line. Simple gauging of distance Measure the distance between two intensity levels

SL Introduction to Optical Inspection24 Improving the result FilteringUsing geometry

SL Introduction to Optical Inspection25 Calibration Transforming pixel to a dimensional unit (mm) Corrections for distortion in the optical system (camera and lens) Using GRID Calibration only related to one measurement plane Scorpion Vision Software can be calibrated in many planes

SL Introduction to Optical Inspection26 Other advantages using Calibration Large ObjectsPerspective 50 cm Camera

SL Introduction to Optical Inspection27 How to build an inspection Perform and validate a number of ”simple” measurements –Dimension –Lines –Greyscale values – colour A set of these measurements are combined to identify specific Conditions

SL Introduction to Optical Inspection28 Image processing example 1.Distance calculated with NearestPointOnLine Tool 2.Based on Calibration tool result directly presented in mm 3.Measurement resolution: better than 0,01 mm 4.Measurement tolerance: estimated to 0,05 mm

SL Introduction to Optical Inspection29