Tuesday, December 4, 2012

Lighting is job one

All those fancy vision tools in your favorite package, none of them inspect the objects passing down your conveyor. All they do is perform measurements on the image the camera acquired. So if the image is not a reliable representation of reality the results will be pretty meaningless.

You vision experts know what I’m driving at: the image is everything and it all starts with lighting that maximizes the signal to noise. In this case the signal is the features you want to detect or measure and the noise is all the other clutter.

We’ve learnt a lot about lighting over the years but sometimes it’s still good to be reminded of the basics, and it used to be that the best material on lighting came from Nerlite. Well Nerlite was absorbed into Microscan long ago, but their material still exists, and has recently been reissued in the pages of Assembly. The article title, “Eight Tips for Optimal Machine Vision Lighting” sums it up nicely.

No comments: