Light curtain

The invention discloses a light curtain, which relates to the field of photoelectric control, and is provided with a first control circuit, a first clock circuit, a second clock circuit, an equipment control circuit, N light-emitting modules and N light-receiving modules, the first control circuit is connected in series with the N light-emitting modules, and the two clock circuits are respectively connected with the light-emitting modules and the light-receiving modules. The two clock circuits are arranged in parallel, clock signals output by the two clock circuits are consistent, the receiving end of the equipment control circuit is connected with the output ends of the N light receiving modules, the control end of the equipment control circuit is connected with the enabling end of the mechanical equipment, and the equipment control circuit controls the mechanical equipment to stop when the number of the light receiving signals received by the equipment control circuit is not equal to N. The mode that the N