When I was experimenting the infra-red LEDs I observed that the mark-space ratio of the received pulse stream varied as the distance varied. It seemed to be useful (easily detectable) from about 5cm to 30 cm but perhaps it could be optimised for different distances. I attributed the effect to the saturation of the receiving LED. I filed the observation away along with the possibility of using it in my window frames to report not just if the window is open, but also by how much. Justin On 1 September 2015 at 11:39, Neil wrote: > Anyone know of a non-contact distance sensor that can measure up to say > 1 inch? I built a machine for maker faire (in less than 2 weeks) that > lets people draw on a touch screen an that will get printed with > frosting on a cookie. But if the cookie is not flat (rarely are they > really flat), there are issue with the frosting not sticking properly in > some corners or sharp curves. I'm thinking if I can map the surface of > the cookie quickly before printing each one, I can have the Z-axis track > the cookie's "terrain". This is a fun project so low-cost is important. > > Cheers, > -Neil. > > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .