Motion Sensors - Optical definition: A motion sensor (or motion detector) is the linchpin of your security system, because it's the main device that detects when someone is in y... Motion Sensors - Optical Product Listing: 189,5578.Sensors, Transducers type:Pressure Sensors, Transducers(84536),Current Sensors(57379),Encoders(27450),Proximity Sensors(21296),Sensor Cable - Assemblies(20019) .Motion Sensors - Optical has 2 pieces of spot stock price information, you can click the "RFQ" button to confirm the inventory and price with the Twicea.