Hi, I have to use a photovoltaic cell to read the degree of light in the room and then light up some LEDs according to the light intensity. I am using a Galileo Arduino compatible board. I don't really get how to rad the degree light in a room, what kind of values should I obtain an d how. Could you help me please?
A solar cell is sometimes used in a wheather station, to measure the amount of daylight. They can withstand direct sunlight, and many light sensors can not. There are sensors that give the amount of lumen. With those sensors you don't have to calculate or calibrate something. At www.adafruit.com they have some light sensors.
Google for : solar cell lux voltage
And click on images.
You will find many graphs that show the amount of light according to the voltage.
Connect the solar cell to an analog input. You might want to use a protection resistor of 1k between the solar cell and the analog input. Read the voltage, and calculate the degree of light.