Reference

Principle

The ML8511 is a UV sensor, which is suitable for acquiring UV intensity indoors or outdoors. iT is equipped with an internal amplifier, which converts photo-current to voltage depending on the UV intensity. This sensor detects 280-390nm light most effectively. This is categorized as part of the UVB (burning rays) spectrum and most of the UVA (tanning rays) spectrum. It outputs a analog voltage that is linearly related to the measured UV intensity (mW/cm2).

Mapping the outputVoltage to intensity is straight forward. No UV light starts at 1V with a maximum of 15mW/cm2 at around 2.8V.

Other Supplementary Information

Arduino has a built-in map() function, but map() does not work for floats. Thanks to users on the Arduino forum, we have a simple mapFloat() function from http://forum.arduino.cc/index.php?topic=3922.0.