The sun-a-wear sensor measures the UV index at irregular intervals. That depends on how much light reaches its solar cell. When the sensor is in the sun, it measures every 5 seconds. In the shade, it does this about every 20 seconds. The sun-a-wear app adds up the measurements to a UV dose.
Measurement precision of the sun-a-wear sensor
We test and calibrate the sensors using a high-precision reference sensor. In comparison, our sensor has a deviation of about 10 to 15%. That may sound like quite a lot. However, if you look at the measurements superimposed, you can see that they are very similar. The more important part for sun-a-wear is the further processing of the data. This further processing allows us to improve the measurement based on other data to better estimate an individual's actual UV exposure.
