The light source in the imaging system of the image measuring instrument is very important

The imaging optical path quality of the image measuring instrument refers to the imaging quality under the influence of the optical lens and lens mounting system used by the imaging probe. The application of the light source has a powerful auxiliary effect on data acquisition, and the light source control is very important for the measurement effect of the image measuring instrument. Good light source design can not only reduce the requirements of image processing algorithms, but also improve the accuracy and efficiency of the system. But it is not possible to select the same light source for any part measurement. Inappropriate lighting will have a great impact on the measurement results of the parts. The role of the light source: illuminate the target component and increase the brightness; form an imaging effect that is conducive to image processing, reduce the complexity of the system and the requirements of image processing algorithms; overcome the interference of ambient light, ensure image stability, and improve system accuracy and effectiveness. The light source in the imager usually includes three types, namely surface light, contour light and coaxial light. According to the classification and application of the light source, it can be divided into: Illumination angle:

Coaxial light: used to measure high reflectivity parts, the circular multi-angle programmable light source can easily achieve deep hole and thickness cross-section Measurement; Surface light: located on the same side of the camera, mainly used to measure the surface size of the object, blind holes and boss measurement; Contour light: through hole measurement and profile measurement, called bottom light, usually more commonly used. Low-angle ring light: used for plastic parts appearance defect detection, bottle mouth defect detection and hardware edge positioning, etc.; high-brightness bar light source: mainly used for character reading of electronic components, destructive testing of large-format products, and large-format Appearance test of printed products; Ring low-angle display without sufficient light source: used for defect detection on workpiece surface, OCR recognition on plastic surface, and capacitive character recognition, etc.; Dome light source: cylindrical surface inspection, surface irregularity defect inspection and appearance Defective electronic component inspection; Linear light source: Mainly used for PCB circuit board measurement and large-format accuracy measurement. In visual inspection technology, image measurement systems and defect detection systems rely on the acquisition of images, and the acquisition of images requires appropriate photos. Ming system. Different light sources act on different parts and different inspection positions. In the inspection process of the image measuring instrument, the light source must be flexibly operated to prepare for obtaining accurate inspection data.