The light intensity of LED’s drops over time. Bogdan wanted to figure out exactly by how much the light intensity of his LED strips dropped, so he build a light intensity logger. It’s basically a closed box with an LED strip and a light intensity sensor inside. An Arduino reads the sensor and stores the reading in its EEPROM.
Very interesting. Does the “light intensity sensor” degrade over time too?
If you’re using a silicon photodiode as the sensor, I’m pretty sure the LED degradation with time will be at least 10x worse than the sensor. However light intensity is difficult to measure. As I recall from a table of the state of the art in measurement accuracy/uncertainty (volts, amps, resistance etc.) the very least accurate one is light intensity.
Have you explored if the current is constant, that the light indensity does not decrease?