There have been multiple versions of the UV sensing element in the Go Direct® Light and Color Sensor (GDX-LC).

The most recent version of the UV sensor has a half-sensitivity range from 300 nm to 425 nm. It is important to note that this range extends into the blue end of the visible light spectrum. This sensor will provide a non-zero response to some deep-blue but visible light sources, such as fluorescent light bulbs. The label indicating the location of the sensor for this version reads “UV-BLUE.”

If the label for the UV sensor is not “UV-BLUE” then the sensor has a half-sensitivity range from 320 nm to 375 nm — spanning most of the region considered to be UVA. This sensor does not respond significantly to the visible light spectrum.

Go Direct Light and Color Sensor Troubleshooting and FAQs