photovoltaic cell or solar cell is a common light sensor device that converts light energy directly into electric energy modern silicon solar cells are basically pn junctions with a transparent p layer shining light on the transparent p layer causes a movement of electrons between p and n layers thus producing a small dc voltage. typical value is 0.5 v per cell in full sunlight.
• The junction of dissimilar materials (n (+) and p (-) type silicon) creates a voltage,
• Energy from sunlight knocks out electrons, creating a electron,
• Connecting both sides to an external circuit causes current to flow,
• In essence, sunlight on a solar cell creates a small battery with voltages typically 0.5 volt DC.