It is the quality level of laser pointer

It is the quality level of laser pointer .
Measured distance X or variation, you can find the bandwidth b, or its variation. Laser ranging. Production practices and scientific research, often encounter the problem of measuring distance. Geodetic and geological exploration, the need to measure the distance between two hills; in the construction of the bridge, you need to measure large Riverbanks interval. In the military, the emplacement of targeting long-range combat and can not do without the correct measurement of the distance. The optical distance earlier proposed a physical distance measuring method, in the early fifties in the late 1940s, made geodimeter and practical application of the measurement of the distance between the ground targets. However, then geodimeter, by the brightness of the light and the monochromatic limit, did not get a lot of development. To inspect the quality of laser pointer .So the case can accommodate laser pointer
In the early sixties, the emergence of the laser played a great role in promoting the development of optoelectronic rangefinder. Laser high brightness, good color, strong direction, a narrow beam, is the ideal light source for optical rangefinder. (As compared to the microwave range finders, optical range finder, etc.) and other rangefinder, laser range finder [30] the detection distance, ranging accuracy, strong anti-jamming, and confidentiality as well as small size, light weight, high repetition rate. To the Moon and artificial Earth satellite laser ranging, a variety of civilian and military laser rangefinder after generations of improvements, has been used extensively for practical work. laser pointer needs to be inspected.
Different from the laser measurement, the length of the laser ranging measurements is much greater. Broken down according to odometry, laser ranging roughly the following three categories: short-range laser range finder, and its measurement range is only five kilometers or less, for a variety of engineering measurement; in the long-range laser rangefinder, measuring range from five to tens of kilometers, for geodetic measurements and earthquake prediction; remote laser range finder for measuring the distance of the missiles, satellites, lunar and other space targets. According to the methods of measurement, laser ranging can be divided into a pulse ranging method and phase ranging France, the former measurement accuracy is relatively low, for not too high in the military and engineering precision in the measurement occasions; the latter is relatively high measurement accuracy, geodetic and engineering survey has been widely used. Figure 6-7 shown below, issued by the dual frequency laser perpendicular linearly polarized light into a polarizing beam splitter group 1 after separation apart two parallel beams of R, respectively, fired at cone angle of the retroreflector components prism and Return to pan some distance along the original direction.