I want to detect from a distance of 1-2cm, in a low light environment, a line drawn on paper, by a UV marker such as the following UV markers:
https://www.ebay.com/itm/353313822362?s … 2749.l2649
What UV sensor should i use? Do UV sensors have an internal UV LED or would i need to add a LED that lights the paper? If i need to add a LED, what kind of LED should i use?
Those types of markers become visible when illuminated with UV light, they don’t produce light on their own.
You’d need a UV light source to make them visible and then a light detector that responds to visible light but not UV to detect the glowing mark. You might need to add some UV filtering to whatever you end up using as a detector if the UV light source can be seen by it.