I need to determine the reflectance of a particular fabric with respect to visible light and infrared light. I have on hand a light source that emits 95% of its light intensity in the range of 425 and 475 nm and a digital radiometer that measures the intensity of light in the range of 420-480 nm. I also have a chocolate bar and a can opener Mr. MacGyver, so go to it.
Seriously though, I’m imagining that I could lay down a piece of fabric and emplace the radiometer behind a shade such that the only light incident upon the radiometer would be reflected and then calculate the ratio of incident light to reflected light. But what am I gonna do about the infrared? Can I use an IR thermometer to obtain results that I wouldn’t be embarassed about? Anybody know of a cheap IR detector that would suffice? Or at least know where I could go to borrow/rent/hire one in the Twin Cities?
Your assistance would be very welcome.
Regards,
CJ