ISSN:
1573-1987
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Summary A rangementer, working at 1,06 μ, using neodymium-doped glass rods, is described. By applying a rotating prism (15000 r.p.m.) as a Q-switch a single pulse is emitted. At a pumpenergy of 55 joules the peakpower is 1 Megawatt and the risetime is 20 nanoseconds. It is shown that the peakvalue of the noise is most important. The different noise characteristics of photomultipliers and high-frequency photodiodes are discussed and a figure of merit relating their performances is defined. It turns out that at a wavelength of 1.06 μ the photodiode is superior. The performance of the rangefinder is given. The maximum distance, which can reliably be measured is plotted against the visual range. The dependence of this curve on different atmospheric conditions (fog, rain, snow) is considered. The device is comparable in performance to those using ruby, with the following advantages: 1. The pumpenergy is reduced by a factor of 5, leading to a reduction in size and weight. 2. The homogeneity and low losses of the material facilitate the construction of the Q-switch. 3. The attenuation, due to scattering in the atmosphere, is much smaller at the longer wavelength of the neodymium laser.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00419625
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