The emitter emits several invisible infrared beams, and the light receiver receives the infrared beams from the emitter, forming a rectangular detection light curtain. The entire set of light curtains detects by scanning beam by beam. Any opaque object larger than a certain size (such as a part of the operator's body, opaque workpieces, etc.) that invades the light curtain area will cause light blocking. When the safety light curtain detects light blocking, it will enter the "abnormal" state within the response time of 20ms - interrupt output (such as the relay going from closed to open state, the transistor going to cut-off state, etc.).
