Ultrasonic Distance Sensor and Laser Distance Sensor are two widely-used device to measure the distance. They both have their own advantages and disadvantages. When choosing suitable distance sensors, we should do specific analysis according to the actual situation. The first difference for ultrasonic distance sensor and laser distance sensor is their working principle. Ultrasonic Range Sensor 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 sensor is composed of ultrasonic generating circuit, ultrasonic receiving amplifier circuit, counting and display circuit. Laser Distance Module is a device accurately using laser to measure distance of the target. The laser distance sensor 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 distance sensor is the most widely used measuring device at present, it can be classified into handheld laser distance sensor and telescope laser distance sensor. 
The performance differences between ultrasonic and laser Distance Measurement Sensors:
1. Accuracy: the measurement accuracy of ultrasonic distance sensor is centimeter level, the measurement accuracy of laser distance sensor is millimeter level; 2. Measurement range: ultrasonic range sensor measurement range is usually within 80 meters, and the measurement range of Laser Range Sensor can reach up to 150 meters, laser pulse measurement range is up to hundreds of or thousands of meters, even further. 3. Error probability: Ultrasonic distance sensor often gets an error, the main reason is that ultrasonic distance sensor 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 sensor is usually from a few dollars to dozens of dollars, laser range sensor price is from dozens of dollars to hundreds of dollars, based on the accuracy, measuring distance and working condition.
Chengdu JRT Main Ranging Modules: Industrial Laser Distance Sensors, Laser Rangefinder Sensor, Tof LiDAR Sensors.
Chengdu JRT Meter Technology Co., Ltd
