We know that industrial laser rangefinders are different from ordinary laser rangefinders. Industrial laser rangefinders have higher measurement accuracy, longer measurement range and wider application range than ordinary rangefinders. However, there are also many types of laser rangefinders. Today we take a look at the classification and measurement methods of industrial laser rangefinders.
According to the distance measured, it can be divided into the following three categories:
1. Short-range laser rangefinder, its measurement range is only within 5 kilometers, suitable for various engineering measurements;
2. Mid- and long-range laser rangefinders, ranging from 5 kilometers to dozens of kilometers, are suitable for geodetic control surveys and earthquake predictions.
3. Long-range laser rangefinders are used to measure the distance of space targets such as missiles, artificial satellites and the moon.
Classification of different ranging methods
(1) Pulse Ranging Method: The rangefinder emits light pulses, and after the light pulses are reflected by the target to be measured, it returns to the rangefinder receiving system to measure the time interval between the emission and reception of the light pulses, that is, the light pulses. The round-trip propagation time T of the pulse over the distance to be measured. The ranging accuracy of the pulse method is mostly in the order of meters.
The requirements of the optical pulse rangefinder: the optical pulse should have sufficient intensity; the directivity of the optical pulse is better. The light pulse monochromaticity is better. The width of the light pulse should be narrow. Lasers for laser ranging: ruby lasers, neodymium glass lasers, carbon dioxide lasers, semiconductor lasers.
(2) Phase Ranging Method: The time T is indirectly measured by measuring the phase change of the continuously modulated light wave propagating back and forth over the measured distance. This method has high measurement accuracy and has been widely used in geodetic surveying and engineering surveying.