What are the technical principles of laser rangefinders?


The principle of pulsed laser ranging technology:

The phase method is similar to the method used in ultrasonic speed and distance measurement. The maximum measurement distance is usually a few hundred meters, which can easily reach the order of millimeters. However, the maximum measurement distance of a rangefinder designed according to this method is limited. Extension. This method is widely used in foreign countries. The pulsed laser ranging generally uses infrared lasers, including near-infrared lasers and mid-infrared lasers. Lasers in this waveband can be divided into visible and invisible. And the rangefinder based on this technology has low requirements for coherence, fast speed, simple implementation structure, high peak output power, high repetition frequency and large range, so this project uses the pulse method to design a handheld laser rangefinder.

The principle of phase method laser ranging technology:

The mainstream laser rangefinder on the market is a laser rangefinder based on the phase method. This is because the laser rangefinder based on the phase method can easily overcome a major defect of ultrasonic ranging: the error is too large, so that the measurement accuracy reaches the millimeter level. The main disadvantage of laser rangefinders based on this method is that the circuit is complex and the operating distance is short (about 100 meters, after the efforts of many scientists, there are now phase-based laser rangefinders with operating distances of several hundred meters) .

The phase method laser ranging technology is to use the laser of the radio frequency band to carry out amplitude modulation and measure the phase difference produced by the distance between the sinusoidal modulated light and the distance between the rangefinder and the target object. According to the wavelength and frequency of the modulated light, the laser is converted Flight time, and then calculate the distance to be measured in turn. This method generally requires a mirror to be placed at the object to be measured to reflect the laser back to the laser rangefinder in the original path, and the discriminator of the receiving module will receive and process it. In other words, this method is a passive laser ranging technology that requires cooperative targets.

Good Thing Recommended :

M120Portable laser distance meter

Aluminum housing design with clip, make it textured and portable. Practical functions satisfy with all needs of daily household meaurement, decorating and construction.