Laser rangefinder measuring range
Illumination ranging methods are divided into phase method rangefinders and pulse method rangefinders. Pulsed laser rangefinders emit a beam or a series of short-lived pulsed laser beams to the target during operation, and the photoelectric element receives the laser reflected by the target. The timer measures the time from emission to reception of the laser beam, and calculates the distance from the observer to the target. The phase method laser rangefinder detects the distance by detecting the phase difference between the emitted light and the reflected light when they propagate in space. The laser rangefinder is light in weight, small in size, simple in operation, fast and accurate, and its error is only one fifth to several hundredths of other optical rangefinders. The picture on the right is a typical phase method rangefinder. and pulse method rangefinder diagram.
What is the error of the laser rangefinder?
The measurement accuracy is based on ISO/R1938-1971 recommended by ISO, 95% reliable statistics (2s, that is, twice the standard deviation). Standard measurement accuracy is the specified measurement error based on the normal measurement environment. Not available in special application functions and calculations, such as Pythagorean measurement and tracking mode (continuous tracking measurement).
There are two ways to use the laser rangefinder: the pulse method and the phase method.
If the laser rangefinder uses pulse emission, the absolute accuracy is generally low, but for long-distance measurement, it can achieve good relative accuracy.
If the laser rangefinder uses the phase test, the accuracy can reach plus or minus 1 mm, which is the highest in the rangefinder.
The error in the accuracy of a laser rangefinder is not proportional to the distance measured and is the same over the entire distance. However, over long distances will increase the error by +/-5ppm (parts per million) (+/-0.5mm/100m).
The accuracy of laser rangefinders has always been concerned by people in the industry, and relatively high-precision laser rangefinders are required in some industries. For medium and long-distance telescope laser rangefinders, the general accuracy of this rangefinder is 1 yard +-1. At present, it can be called a high-precision laser rangefinder, with an accuracy of 0.5 yards +-1. This high-precision rangefinder has an accuracy of less than 0.5 yards within 100 meters.
The main error of a rangefinder comes from measurement errors. For example, the laser light is blocked or penetrated, the measurement end point is incorrectly selected, and the rangefinder selects the measurement start point incorrectly. Under ideal conditions, the error is small.
