Fiber Optic FU Sensor

The FU Series from KEYENCE is a versatile line of fiber optic sensor units designed for precise detection in industrial automation, offering multiple sensing types, high environmental resistance, and flexible installation options.OverviewThe FU Series fiber optic sensors consist of sensor heads (fiber units) connected to a fiber optic sensor amplifier, which contains the light source and processing electronics. The fiber units themselves are used solely to transmit and receive light, allowing detection in tight spaces, harsh environments, or areas where conventional sensors cannot be used. These sensors detect targets by measuring changes in light intensity caused by reflection, refraction, or obstruction of the transmitted light, enabling highly accurate detection even in challenging conditions .Types of FU Fiber UnitsThe FU Series offers a wide variety of sensing heads to suit different applications:Through-beam type: Light passes directly from emitter to receiver, ideal for precise object detection and long distances .Reflective type: Detects objects by measuring light reflected from the target surface, suitable for small or irregular objects .Retro-reflective type: Uses a reflector to return light to the sensor, effective for detecting objects at a distance or in narrow spaces .Definite-reflective type: Provides long-distance detection with high precision, often used for circuit board or wafer inspection .Area detection type (e.g., FU-E40): Uses an area light to detect targets passing in various positions, minimizing interference from dust or gradual light changes .Key FeaturesEnvironmental resistance: Many FU units are resistant to water, chemicals, oil, and high temperatures (up to 350°C / 662°F) for industrial applications .Flexible installation: Thin, compact fibers with stainless steel jackets allow mounting in tight or complex spaces .High precision: Certain models, such as FU-35FZ and FU-35TZ, offer high sensitivity and anti-interference capabilities for harsh environments .Long detection distances: Some units can detect objects up to 900 mm (FU-61) or 1800 mm (FU-71), depending on the model .Durability: Unbreakable fibers and robust housings ensure reliable operation in demanding industrial settings .ApplicationsFU Series fiber optic sensors are widely used in factory automation, including:Detecting small or irregular objects in tight spacesMonitoring liquid levels in tubes or tanksCircuit board inspection and wafer mappingHigh-precision positioning and alignment tasksEnvironments with dust, oil, or extreme temperaturesSummaryThe KEYENCE FU Series provides a flexible, durable, and precise solution for industrial detection needs. By separating the amplifier from the fiber head, these sensors allow installation in restricted or harsh environments while maintaining high detection accuracy. With multiple sensing types and specialized models, the FU Series can be tailored to a wide range of applications, from general object detection to high-precision industrial automation .