Principle for Choosing and Measuring a Laser Range Finder
1. Understand the required range;
2. Accuracy requirements;
3. Do you need other functions such as height measurement and angle measurement?
Generally, the 200m range finder is a handheld device, and the shape of the large range is similar to that of a telescope, also called: a range finder.
Measuring principle and function method
With the development of science and technology, it seems that most people don't know about laser range finders, and don't understand laser range finders. Some workers even use measuring tapes to measure distances, and use pens to calculate areas, volumes, and so on. Let me introduce the principle and usage of the laser range finder, which can allow workers to work and study with high efficiency and high precision.
The laser rangefinder is an instrument that uses laser to accurately measure the distance of the target. When the laser range finder is working, it emits a very thin laser beam to the target, and the photoelectric element receives the laser beam reflected by the target. The timer measures the time from the launch to the reception of the laser beam, and calculates the distance from the observer to the target.
If the laser is emitted continuously, the measurement range can reach about 40 kilometers, and the operation can be carried out day and night. If the laser is emitted in pulses, the general accuracy is low, but it can achieve good relative accuracy for long-distance measurement.
Measuring Principle and Method of Laser Range Finder
1. What is the principle of using infrared ranging or laser ranging?
The principle of ranging can basically be attributed to measuring the time required for light to go back and forth to the target, and then calculate the distance D through the speed of light c = 299792458m/s and the atmospheric refraction coefficient n. Because it is difficult to measure time directly, it is usually to measure the phase of continuous wave, which is called phase measuring range finder. Of course, there are also pulse rangefinders, typically WILD's DI-3000
It should be noted that phase measurement does not measure the phase of infrared or laser, but the phase of the signal modulated on infrared or laser. The construction industry has a handheld laser distance meter for house surveying that works on the same principle.
2. Must the plane of the measured object be perpendicular to the light?
Usually precision distance measurement requires the cooperation of a total reflection prism, while the rangefinder used for house measurement directly measures with smooth wall reflection, mainly because the distance is relatively short and the signal strength of the light reflected back is large enough. It can be known from this that it must be vertical, otherwise the return signal is too weak and the maximum distance cannot be obtained.
3. Is it possible if the plane of the measured object is diffuse reflection?
It is usually possible. In actual engineering, a thin plastic plate is used as a reflective surface to solve the problem of serious diffuse reflection.
4. The accuracy of ultrasonic ranging is relatively low, and it is rarely used now.
