Liiketunnistin

Liiketunnistin is a Finnish term that translates to motion sensor or motion detector in English. It refers to an electronic device that detects movement. These sensors are widely used in various applications for security, automation, and convenience.

The most common types of liiketunnistimet utilize passive infrared (PIR) technology. PIR sensors detect changes in infrared radiation emitted by warm objects, such as humans and animals. When a warm body moves within the sensor's field of view, it disrupts the infrared pattern, triggering the sensor. Another type is microwave motion sensors, which emit microwave pulses and detect changes in the reflected signal caused by movement. Ultrasonic motion sensors work by emitting ultrasonic sound waves and detecting alterations in the reflected waves.

Liiketunnistimet are integral components in home security systems, triggering alarms when unauthorized movement is detected. They are also employed in automatic lighting systems, turning lights on when someone enters a room and off after a period of inactivity. Other applications include automatic doors, energy management systems, and even in some types of smart home devices to control various functions based on occupancy. The sensitivity and range of liiketunnistimet can vary greatly depending on their design and intended use.