Light curtain

A light curtain that includes

• a light projector including a plurality of first light projecting elements,
• a light receiver arranged to face the light projector, and including a plurality of first light receiving elements configured to receive light beams projected from the plurality of first light projecting elements, and
• a synchronization unit configured to synchronize a light projection timing of the light projector and a light reception timing of the light receiver by optical communication,
• a safety signal generated based on whether or not each of a plurality of optical axes formed between the light projector and the light receiver is in a light shielding state being output to an outside, the light curtain comprising:
• a first operation indicator lamp provided in the light projector and configured to display an operation state of the light curtain;
• a second operation indicator lamp provided in the light receiver and configured to display the operation state of the light curtain;
• at least one set of optical elements provided in each of the light projector and the light receiver and configured to interlock and display the first operation indicator lamp and the second operation indicator lamp;
• and
• a control circuit configured to interlock and display the first operation indicator lamp and the second operation indicator lamp by using the at least one set of optical elements.