Brief introduction of laser range finder
Brief introduction of laser range finder
1. 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 laser rangefinder 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 pulsed rangefinders.
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. The plane of the measured object must be perpendicular to the light
Usually precision distance measurement requires the cooperation of a total reflection prism, while the rangefinder and infrared thermometer used for house measurement directly measure 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. Laser plummet can measure the object plane as 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.
5. The accuracy of the laser rangefinder can reach 1 mm error, which is suitable for various high-precision measurement purposes.
Laser rangefinder use: Laser rangefinder is widely used in terrain survey, battlefield measurement, tanks, aircraft, ships and artillery laser rangefinder
Range measurement of targets, measurement of altitudes of clouds, aircraft, missiles and artificial satellites, etc. It is an important technical equipment to improve the accuracy of high tanks, aircraft, ships and artillery. Due to the continuous reduction in the price of laser range finders, laser range finders have gradually begun to be used in industry, which can be widely used in industrial measurement and control, mines, ports and other fields.
