SparkFun Proximity Sensor Breakout - 20cm, VCNL4040 (Qwiic)

The SparkFun Proximity Sensor Breakout is a simple high-performance IR presence and ambient light sensor built around the VCNL4040 from Vishay. If you have ever used an automatic paper towel dispenser or a touchless soap dispenser you have likely interacted with this type of technology.This sensor is the perfect digital alternative to popular analog "Sharp" sensors. But what separates it from them is that it has absolutely no dead zone. Unlike many sensors that require an object to be at least 4cm away to be detected the VCNL4040 can detect objects up to the face of the sensor making it ideal for close-range detection and touchless interfaces.Qualitative vs. QuantitativeIt is essential to understand that this is a qualitative sensor not a quantitative one.What it does: It detects if an object is present within its 20cm range and determines if it is getting closer or moving farther away.What it doesn't do: It does not provide a precise millimeter distance reading (e.g. "The object is exactly 177mm away").If your project requires precise millimeter-accurate distance measurements we recommend checking out our Time-of-Flight (ToF) sensors. But for detecting presence gestures or collisions the VCNL4040 is what you need.Two Sensors in OneIn addition to proximity the VCNL4040 features a built-in Ambient Light Sensor (ALS). This allows the board to measure lux and the lighting conditions of the environment making it great for adjusting screen brightness controlling automatic night lights or triggering your next glitter cannon.Easy Integration & No-Code LoggingUtilizing the handy Qwiic Connect System no soldering is required to connect the VCNL4040 to the rest of your system. However if you want to skip the programming entirely this breakout is fully compatible with the SparkFun OpenLog Artemis and DataLogger systems. When connected the sensor is automatically detected scanned configured and logged. This allows you to start gathering proximity data immediately! No programming soldering or complex setup required.By eliminating the "blind zone" found in legacy sensors the VCNL4040 offers effective detection from 0 to 20cm. Paired with excellent ambient light suppression it ensures consistent readings in fluctuating environments making it a dependable solution for precise short-range presence detection.