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Published on: 07/09/2020

Last Reply on: 01/27/2021

Category: Non-Visible Imaging

Technology: Vision

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What would be the best lighting solution for inspecting glass parts within a polycarbonate plastic enclosure?

7 Replies

A3 Member Expert

I am assuming that both the glass and polycarbonate are clear and transparent. I see two options. If the glass has a lower transmission than the polycarbonate in the infrared region, infrared backlighting might work. If the transmissivity of the two is the same within a reasonable wavelength range, then you need to take advantage of the differences in index of refraction. The easiest way to image this is with a collimated (telecentric) backlight. You might experiment with a polarizing sensing camera which are available from several camera companies. There are other techniques (e.g., schlieren imaging), but they are far more difficult to implement. You can contact me if you have more questions.

Perry West from Automated Vision Systems, Inc. | 07/09/2020

Cyth Systems, Inc. Logo

Kyle, As Perry hinted at this could be a challenging issue depending on the two surfaces you are looking at, If you have samples you are willing to share, we can undertake a vision study and see if we can get any results that would be usable in a system. Andy

Andrew Long from Cyth Systems, Inc. | 07/09/2020

Gibson Engineering Logo

Hey Kyle, The simple answer is that it depends, I say there is no one perfect solution! It depends on the thickness of the enclosure, the transparency of the glass, and what inspection you are actually going for. I very recently helped with an application using IR light which would "burn" through the plastic enclosure but would not make it through the substance it contained ... worked great when we were doing presence/absence and basic measurement. Here at Gibson we represent a number of different lighting manufacturers and have a complete vision lab to test parts/applications/projects out (usually we perform vision evaluations with our Cognex cameras), shoot me an email if you'd like to know more!

Brett Concannon from Gibson Engineering | 07/09/2020

Machine Vision Lighting Inc. Logo

We can not understand it without looking at the actual one, but if you use our V-ISA lighting, you can see the 3D information of most things and the change of the surface condition, so please consider it.

Shigeki Masumura from Machine Vision Lighting Inc. | 07/14/2020

Opto GmbH Logo

Hi Kyle, our new Imaging Modules, and Digital Microscope have both a Coaxial LED and a Ringlight LED, which you can use on option: Take a look at our homepage: If you send us samples, we can make tests for you. Sometimes we use a light source from above and a mirror underneath. Are you already using a Microscope - which one? Contact us at: [email protected]

Sandra Rossberg from Opto GmbH | 07/16/2020

Smart Vision Lights Logo

Kyle, thank you for your question. We can help you with this however to do so with the best results there is more information needed. Please reach out to Nolan Greve our Applications Specialist and he would be happy to assist you. 231-722-1199 or [email protected]. Also feel free to visit our website at Thank you, Dave Spaulding

Dave Spaulding from Smart Vision Lights | 08/13/2020

EVT Eye Vision Technology GmbH Logo

I would suggest a Hyperspectral Camera, with the resulting Cube you can work very well.

Michael Beising from EVT Eye Vision Technology GmbH | 01/27/2021