This circuit senses the brightness levels in the surroundings and converts it into a analog signal which the micro-controller converts and displays the brightness that it senses. This circuit works with Atmel Atmega device, Arduino and other micro-controllers. This circuit is basically a variable voltage divider. If the LDR senses more brightness, the voltage from the output decreases, the darker the LDR is in, the output voltage increases. Stay tuned for the code that I used for this light sensor with my Atmega micro-controller.
Above is what an LDR used in the circuit looks like.
