Different Type of Sensors for Automatic Doors

Here's an brief introduction about the radars /sensors which assembled in TSTC automatic sliding doors, swing doors , they are Microwave Sensor, Infrared Sensor, Ultrasonic Sensor, Laser Detective Sensor .

1. Microwave Sensor

The microwave sensor is the most widely used sensor for automatic doors,  it detects motion based on the doppler effect (frequency shift of reflected waves).

Features

▪  Wide detection range (typically 3–10 meters).

▪  Works well in various weather conditions (rain, fog, dust).

▪  Detects movement only (not suitable for stationary objects).

▪  May have false triggers from moving objects outside the intended area.

▪  Best for High-traffic areas like shopping malls, airports.

2. Infrared (PIR) Sensor (Passive Infrared Type )

The infrared sensor detects the objects through the temperature /heat (infrared radiation).

Features

▪  Energy-efficient (consumes less power than radar).

▪  Works best for human detection (not affected by wind or moving objects like curtains).

▪  Limited range (usually 1–5 meters).

▪  Affected by temperature changes (may fail in extreme heat/cold).

▪  Best for Indoor automatic doors (offices, hospitals).

3. Ultrasonic Sensor

The Ultrasonic Sensor adopt the sound waves to detect objects.

Features

▪  Detects both moving and stationary objects.

▪  Short to medium range (0.5–5 meters).

▪  Slower response time compared to radar.

▪  Affected by air turbulence and noise.

▪  Best for Sliding doors where object presence (not just motion) matters.

4. Laser Detective Sensor

The Laser Detective Sensor adopt the laser pulses for accurate distance measurement.

Features

▪  High accuracy (millimeter-level precision).

▪  3D mapping capability (useful for smart door systems).

▪  Expensive compared to microwave/PIR sensors.

▪  Limited performance in direct sunlight or fog.

▪  Best for Advanced automatic doors in smart buildings.

Brief Comparison for the 4 types of radars above .

How To Choose a Suitable Sensor ?

Indoor vs. Outdoor Use (Microwave sensor for outdoor，PIR sensor for indoor).

Traffic Density (Sensor for high traffic，PIR for controlled access).

Energy Efficiency (PIR consumes less power).

False Trigger Prevention (Microwave sensor may need tuning to avoid interference).