Backlight in industrial Machine Vision:

Shadow images for checking contours and transparent objects

 

There are two types of backlight lighting: Diffuse backlight illuminates the contour of an object, which creates a shadow image and facilitates the detection of outer outlines and free inner contours. Collimated backlight or telecentric backlight is suitable for specific applications such as the inspection of deep objects and objects with curved edges, as they enable more precise edge imaging. This directional homogeneous backlight also scores more points when inspecting semi- and transparent objects.

Find out more about the different types of backlight illuminations: