I am experimenting with IR video cameras. They have a broad sensitivity peak at 940 nm. There is a filter blocking 750 nm and shorter in front of the sensor.
I am looking for an IR fluorescent substance to use for markers in the scene the camera is observing. Something that can be turned on with ultraviolet illumination bursts so I can differentiate between my markers and other IR sources.
My hope is for some affordable and harmless substance. Something that could be mixed with polyester, acrylic or epoxy potting compound wold be nice. An already solid watherproof material is even better.
My searches so far have found some IR fluorescent stains for microscopy but I am afraid they are expensive.
This might be a physics question also but I think chemists works a lot with IR absorption and IR fluorescence.