Spacer
Distance lines , also distance threads or Reichenbach 's distance threads, are a pair of parallel lines equidistant from the center on the reticle of rifle scopes of surveying instruments and firearms. They are used to determine the distance to an object. From the metric distance, e.g. B. read on a leveling staff, the distance can be determined by simple calculation. The spacer threads are usually attached at a distance at which the distance is determined by multiplying the read distance by a factor of 100.
In the picture, the distance read on the leveling staff with decimeters is:
- (15 dm - 13.45 dm) 100 = 1.55 dm 100 = 155 dm = 15.5 m.
literature
- Fritz Deumlich : Instrument science of surveying technology . 7th revised edition. VEB Verlag für Bauwesen, Berlin 1980.