Coolens Lens
Coolens is the machine vision lens brand of Shenzhen Vico Technology, which has concentrated on industrial optics since 2008 and is among the largest lens manufacturers in China by volume. The range covers telecentric lenses for measurement, FA lenses for general inspection, and custom optical modules. A telecentric lens is what keeps a measurement honest: because its rays enter parallel to the optical axis, a part does not appear to grow or shrink as its distance to the camera changes, and a dimension read at the edge of the field agrees with one read at the centre. That single property is the difference between a dimensional gauge and a camera that merely takes a picture of the part.