Introduction Automatic doors rely on sensors to detect approaching people and trigger the door mechanism. PIR sensors are a popular choice due to their low cost, reliability, and ability to detect warm bodies. Types of Automatic Door Sensors PIR sensors:…

Introduction Vending machines are becoming smarter. PIR sensors play a key role in detecting approaching customers, waking up the machine, and powering down when no one is around. Applications in Vending Customer Detection When a person approaches, the machine can:…

Introduction Smart lighting systems combine PIR occupancy sensing with daylight harvesting (adjusting light levels based on available sunlight) to maximize energy savings. This article explains the integration. What is Daylight Harvesting? Daylight harvesting automatically dims or turns off electric lights…

Introduction Energy harvesting – powering devices from ambient energy (light, vibration, heat) – is becoming practical. Ultra-low power PIR sensors are key enablers for maintenance-free wireless motion sensors. The Power Challenge A typical wireless sensor must operate for years on…

Introduction Robots often need to detect people for safety, interaction, or following. PIR sensors provide a low-cost, low-power solution for human detection in robotics applications. Applications in Robotics Human Detection for Safety When a robot detects a person nearby, it…

Introduction Traditional PIR sensors output an analog voltage or a simple digital pulse. Newer digital PIR sensors integrate amplification, ADC, and digital logic, offering I2C interface for configuration and readout. Advantages of Digital PIR Sensors Programmable parameters: Sensitivity, threshold, timing…

Introduction Curtain lenses, also known as long-range or corridor lenses, are specialized Fresnel lenses that create a narrow, elongated detection pattern. They are essential for applications requiring long-distance detection. How Curtain Lenses Work Unlike wide-angle lenses that spread zones across…

Introduction Counting people entering and exiting a space is valuable for retail analytics, building occupancy management, and security. While cameras are common, PIR sensors offer a privacy-preserving alternative. Challenges of People Counting with PIR Single sensor cannot determine direction (entry…

Introduction Most pyroelectric sensors include an integrated JFET (Junction Field Effect Transistor) configured as a source follower. This buffer converts the extremely high impedance of the pyroelectric element to a more manageable level and provides initial amplification. Why a JFET…

Introduction Almost all PIR sensors use a dual-element design. This is not arbitrary – it’s essential for the sensor’s function. This article explains why two elements are better than one. The Problem with Single-Element Sensors A single pyroelectric element responds…