Telecentric Optical Vision Measurement System Parameters On The Accuracy Of The Influence Mechanism

With the rapid development of optoelectronic technology and computer technology,machine vision inspection has become a very important aspect in the industrialproduction. The workpiece is required to have high precision by manufacturers. Theaccuracy of measurement is up to micrometers. The so-called machine vision, we cansee from the literal which is the visual function of the computer. It appears because wehuman eye does not recognize the object, then a computer you can used instead ofhuman eye. And machine vision products are integrated to form a machine visionsystem.Hardware and software are included in a complete set of machine vision systems.Lens, camera, light source, image acquisition card, PC, monitor and line are included inhardware. Software is an image processing system and responsible for patternrecognition, comparison, characteristics extraction, spatial information extraction, anddepending on the application object. Different applications are needed to develop.Characteristics of the machine vision system are good safety, high resolution,reproducibility, and the ability to have a full inspection. Also it can reduce labor costs.In the photoelectric vision measurement system, a combination of generalindustrial lens and calibration plate conscious is often required to reduce the distortionof the lens and lens magnification on measurement accuracy by using a softwarealgorithm. In some occasions it is unable to adopt such a composition to be measured.For example, the need for greater depth of field range of the working environment,which is not only by the algorithm will be able to solve the problem. Telecentric lenscompared to ordinary industrial lens with low distortion characteristics of high depth offield, high resolution. So telecentric optical vision measurement system in the field ofmachine vision measurement occupies an extremely important position.After determining accuracy specifications in telecentric machine visionmeasurement system, with highly reflective cylinder as the object to be measured,characteristics of the light source, the object, the image are researched in different lighting conditions and different lens conditions. According to these characteristicscombined with relevant Principles of Optics, the accuracy of the telecentric opticalvision measurement system is improved.This paper will examine the results are applied to a typical industrial parts-PINlatch edge of irregular shape detection. A new method for optical imaging based on theprinciple of telecentric vision is proposed. The problem of high precision and fastmeasurement of the irregular edges with a certain thickness is solved. The experimentapplication and theoretical analysis show that the edge sharpnesses of the flat PIN, thequadrilateral PIN and the cylindrical PIN are respectively increased by2.8%,10.4%and21.4%, after imaged by telecentric vision system. It is clear that the telecentric visionsystem is more beneficial to inspect the workpiece with thickness and smooth transitionedge.