1. A device that produces an electric current or voltage when exposed to light, used in cameras, light meters, and automatic door openers.
Usage: Also called photoelectric cell or photosensitive cell.; Common in electronics and automation.

Examples

• The photocell in the camera measures light to set the correct exposure.
• Automatic doors use a photocell to detect when someone approaches.
• A photocell converts light energy into electrical signals.
• The light meter contains a photocell that helps photographers adjust their settings.
• Street lamps often use photocells to turn on at dusk and off at dawn.