I'm looking for equipment that can measure the UltraViolet% (UV), Visible Light Transmittance% (VLT), & InfraRed% (IR)Solar Energy. I need this type of product(s) because I'm a Dealer/Installer of Solar Window Films for Automotive & Buildinguse. I found a couple of handheld radiometers thru the internet, but what I'm looking for is equipment that I can use to show customers the percentage of solar energy and (VLT) that penatrates the chosen film from the other side, also I have to do this in the evening when there is no sunlight
? Any Help Guys?? 