Ultrasonic Rangefinder VS Laser Rangefinder

Ultrasonic rangefinder and laser rangefinder are two widely-used tools to measure the distance. They both have their own advantages and disadvantages. When choosing suitable rangefinders, we should do specific analysis according to the actual situation.

The first difference for ultrasonic rangefinder and Laser Rangefinder is their working principle.

Ultrasonic rangefinder calculates the distance based on the transmission speed of the ultrasonic wave in the air(known) and the characteristic that ultrasonic wave encounter obstacles will reflect back. Ultrasonic emitter emits ultrasonic wave to a certain direction, the launch timing starts at the same time, the ultrasonic wave spreads in air and return immediately when encounters obstacles, then the ultrasonic receiver receives the reflected wave and interrupts immediately to stop timekeeping. According to the time difference between transmitting and receiving time, the distance between launch point and the obstacles can be calculated. By continuously detecting the echo reflected by the obstacle after the generated wave is transmitted, the time difference T between the transmitted ultrasonic wave and the received echo is measured, and then the distance L is calculated. Ultrasonic range finder is composed of ultrasonic generating circuit, ultrasonic receiving amplifier circuit, counting and display circuit.

laser range finder is a device that uses laser to accurately measure the distance of the target. The laser rangefinder shoots a very concentrated laser to the target when it is working. The photoelectric element receives the laser beam reflected from the target. The timer measures the time from the laser beam to the reception and calculates the distance from the observer to the target. Laser rangefinder is the most widely used measuring device at present, it can be classified into handheld laser rangefinder and telescope laser rangefinder.

The performance differences between ultrasonic and laser range finder:

1. accuracy: the measurement accuracy of ultrasonic rangefinder is centimeter level, the measurement accuracy of laser rangefinder is millimeter level;

2. measurement range: ultrasonic range finder measurement range is usually within 80 meters, and the measurement range of handheld laser range finder can reach up to 200 meters, laser ranging telescope measurement range is up to hundreds of or thousands of meters, even further.

3. Error probability: Ultrasonic rangefinder often gets an error, the main reason is that ultrasonic rangefinder is acoustic emission, fan of acoustic emission characteristics, so when sound waves through the obstacles is large, the sound waves bounce back more. The more interference, the more prone to error, and the laser distance meter is a tiny laser beam to launch out and come back, so as long as the light beam can pass, almost no interference.

4. price: the price of ultrasonic range finder is usually from a few dollars to dozens of dollars, laser range finder price is from dozens of dollars to hundreds of dollars, based on the accuracy and measuring distance.