As photons (light) land on the detector, the resistance will decrease. The more light is we will have a lower resistance. By reading different values from the sensor, we can detect if is it light , ...

UV (ultraviolet) sensors of all sorts have been an interest of mine. They become interesting when you find the diversity of real-world practical applications. While searching for affordable UV light ...

An Arduino uses a set of LEDs and an RFID reader to bring the object alive. A matching ring contains the RFID tag that activates the lights when held up to the lantern’s lens.