1. Transmission of Light/Sound/Electromagnetic Waves: A signal is emitted via a laser transmitter, ultrasonic generator, or radio wave modulator. The signal travels through the air, reflects off the target object, and is received by the receiver.

2. Time/Phase Measurement: The round-trip time or phase difference of the signal is recorded. Based on the speed of light (approximately 3×10⁸ m/s), sound (approximately 340 m/s), or electromagnetic waves (close to the speed of light), the distance is calculated.

Main Types and Characteristics

· Pulse Method: Short laser pulses are emitted, and the distance is calculated by measuring the round-trip time. It offers high accuracy (±1 mm to ±5 mm) and is suitable for long-distance measurements (50 m to 2000 m for typical handheld models).

· Triangulation Method: Distance is measured based on the principle of laser triangulation. Accuracy is inversely related to the measurement range, meaning higher range typically results in lower accuracy.

· Laser Range Finder:

· Ultrasonic Range Finder: Emits ultrasonic waves and calculates distance using the time difference of reflected sound waves. It has lower accuracy (affected by environmental noise) and is mostly used for short-distance measurements.

· Infrared Range Finder: Emits infrared light and is suitable for long-distance measurements (e.g., Earth-Moon distance) but is easily affected by obstacles.

Key Components

· Transmitter: Generates laser or sound wave signals, such as laser diodes or ultrasonic generators.

· Receiver: Receives reflected signals and converts them into electrical signals, such as photodiodes or microphones.

· Timer/Processor: Measures the round-trip time of the signal and calculates the distance using algorithms.

Application Scenarios

· Power Construction: Used for power line positioning, conductor sag measurement, etc., requiring high accuracy and long-distance measurement capabilities.

· Architectural Surveying: Enables rapid measurement of building spacing and topographic data.

· Industrial Inspection: Applied in equipment installation calibration, material thickness detection, and more.