In this example, the difference in reflectivity between the solder and the legends produces a high-contrast image. He has taught courses in lighting for machine vision, and he has presented papers on lighting at international conferences. Choose a Light Type Light can come from various types of sources, and knowing what light can do will help you select the best source for your inspection job. You should also know about the techniques you can use to light a product. The most popular light sources used for inspection are described below.
Fluorescent lamps provide a highly diffuse, cool, white source of light.
Halogen lamps furnish a high-intensity light source that has a broad spectrum. Halogen light sources may provide a fiber-optic cable that directs light to specific points for front and back lighting. Fiber-optic lamps can shape light into slits, rings, and other forms. Light emitting diodes , or LEDs, supply monochromatic light that you can pulse or strobe. Coherent light can have some disadvantages such as causing speckling and diffraction, and lasers have stringent safety requirements.