Laser triangulation depends upon capturing a small amount of reflected energy in the imaging system. Most materials can be scanned using laser triangulation.
Specular vs. Diffuse Reflection
The scanner must be able to see a reflection from the object being scanned to gather data. The laser or camera cannot be obstructed, and the target must have at least some component of diffuse (multi-direction) reflection. Diffuse materials will reflect the reference laser in “all” directions. Specular reflection refers to a mirror-like surface where incident light is reflected in equal and opposite direction. Even highly specular reflective material may be scanned with appropriate scan zone design. However, an object with a purely specular surface cannot be scanned as the reflected beam will have no component directed at the image sensor.
Learn more about 3D and 2D machine vision at Hermary’s Guide to Unlocking Your Automation Potential.