Regardless of the illumination technology (fiber optic or LED), the technologies used in microscopy and Machine Vision follow the same physical rules. Achieving sufficient contrast is always the chief task in illuminating the object. Without good contrast, the object properties that are to be examined are not visible to either the human eye or the Machine Vision system.
The different illumination techniques can be divided into three categories:
Brightfield illumination
Direct and diffuse incident light, coaxial illumination, line illumination
