Active Infrared Sensor

An active infrared sensor is a device that uses active infrared light emission and detection of its reflection or interruption to determine the presence or movement of an object. It typically consists of an infrared emitter and an infrared receiver. It is widely used in automation, security, and consumer electronics fields that require non-contact detection, positioning, or triggering.

Working Principle

The core of an active infrared sensor lies in the infrared emitter continuously emitting infrared light of a specific wavelength. When there are no obstacles in front, the infrared light does not return or is not received by the receiver. Once an object approaches or passes by, the infrared light is reflected or blocked, causing the receiver to detect the reflected signal or signal interruption, thereby determining the presence or change of the target.

Key Features

• Fast response: Typically responds within milliseconds, suitable for high-frequency detection.
• Unaffected by visible light: Exhibits strong adaptability in environments with strong interference from ambient light, dust, etc.
• Suitable for various materials: Can detect different materials such as metal, plastic, glass, and liquids.
• Low cost and simple structure: Easy to integrate into end products in large quantities.
• Non-contact detection: Effectively avoids wear and tear, suitable for use in harsh environments.

Typical Applications

Active infrared sensors have widespread applications in modern life and industrial automation. In automatic door systems, active infrared sensors can precisely detect approaching personnel and control door opening and closing, enhancing convenience and safety. In elevator systems, they are used to detect passenger entry and exit, enabling intelligent control. In industrial production lines, active infrared sensors are commonly used in object counting, product positioning, and dimensional inspection processes, improving production efficiency. In robotics, they are used for path avoidance, distance measurement, and target recognition, helping robots achieve autonomous navigation.

Notes

• Installation angle and distance settings must be reasonable to ensure optimal reflection or alignment.
• Infrared interference (such as sunlight) may cause false triggers, so avoid using them under direct strong light.
• Reflective sensors are highly dependent on the surface material of the object, with shiny flat surfaces providing better reflection.
• Regularly clean the transmitter and receiver windows to prevent dust buildup from affecting sensitivity.

SUCH active infrared sensors offer advantages such as flexible application and strong adaptability, making them an indispensable sensing component in numerous smart devices, industrial systems, and everyday scenarios.