Laser rangefinder technical indicators
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 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. 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 accurate 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.
Application of handheld laser range finder in house measurement
Application of handheld laser range finder in house survey House survey has always been a concern and bother for the housing management department. It is not only directly facing the old
The common people, and it is directly related to the economic interests of the common people, so the control of the measurement error of the house is particularly important.
It can meet the basic requirements, but there are large errors in the measurement of long-distance, high-level, and difficult-to-reach places, and there are shortcomings such as high labor intensity and complicated work. In today's rapid development of high-tech, so
The original and traditional measurement methods obviously do not meet the fast and efficient requirements of today's information society. For this reason, after introducing two Leica handheld laser rangefinders, after several months of actual use, the overall opinion is that
The instrument is especially suitable for the measurement of buildings with complex structures, mid-rise buildings and long distances. Easy to use, accurate measurement data (3 mm accuracy), improved work efficiency (non-contact measurement), completely discarded a
The method of measuring houses with a tape measure (or steel tape measure) reduces surveying errors, ensures the accuracy of area measurement, and makes the owners more convinced by the measurement results. Of course, the instrument also has aspects that need to be improved urgently, such as under strong sunlight,
Long-distance target objects are difficult to see clearly, and accessories such as binoculars are required. In addition, it is laborious to calibrate the level bubble for each measurement, and it may be automatically calibrated.
Measuring principle and function method of laser range finder With the development of science and technology, it seems that most people don't know that there is a laser range finder, and they don't understand the laser range finder. 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 absolute accuracy is generally low, but for long-distance measurement, good relative accuracy can be achieved. The world's first laser was successfully developed in 1960 by Maiman, a scientist from the Hughes Aircraft Company of the United States. The U.S. military soon launched research on military laser devices on this basis. In 1961, the first military laser range finder passed the demonstration test of the US military, after which the laser range finder soon entered the practical complex. The laser range finder is light in weight, small in size, easy to operate, fast and accurate, and its error is only one-fifth to several hundredths of other optical range finders, so it is widely used in terrain measurement, battlefield measurement, tank , Aircraft, ships and artillery to the target range, measuring the altitude 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, the industry has gradually begun to use laser range finders. A batch of new miniature rangefinders with the advantages of fast ranging, small size and reliable performance have emerged at home and abroad, which can be widely used in industrial measurement and control, mines, ports and other fields. Main classification One-dimensional laser rangefinder is used for distance measurement and positioning; Two-dimensional laser rangefinder (Scanning Laser Rangefinder) is used for contour measurement, positioning, area monitoring and other fields; Three-dimensional laser rangefinder (3D Laser Rangefinder) is used for 3D contour measurement, 3D space positioning and other fields. Figure: Schematic diagram of using laser to measure the distance from the moon to the earth Measuring principle and method of laser rangefinder 1. What is the principle of using infrared 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 type 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 accurate 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.
