The Omron EE-SPY402 is a compact diffuse reflective photoelectric sensor designed for near-contact object detection. It uses an infrared LED and a phototransistor receiver in a single through-hole package, sensing white paper targets at a maximum distance of 0.197 mm. The NPN open-collector output with Light-ON logic provides a sinking signal that connects directly to PLC input modules without external pull-up resistors. This sensor is built for applications where space is tight and the target passes within a millimeter of the lens — think PCB presence detection, edge sensing on small parts, or registration mark detection in compact assembly fixtures.
Omron continues to manufacture this part, so new designs can proceed without a last-time-buy risk. For dual-sourcing, the EE-SPZ401-A shares the same NPN open-collector output and 5 V supply but uses a retroreflective sensing method with a longer range — it is a functional alternative only if the application can tolerate the different sensing geometry and requires a mirror target.