GUVA-S12SD UV Sensor
The GUVA-S12SD UV Sensor chip is suitable for detecting UV radiation in sunlight. It can be used in any application where you want to monitor for the amount of UV light and is simple to connect to any microcontroller.
The module, with a typical UV detection wavelength of 200 – 370nm, outputs a calibrated analog voltage which varies with the UV light intensity so basically all you need to do is connect this to an ADC input and read in the value. This value ties in with the UV index.