A rangefinder is a device that measures distance from the observer to a target.
Techniques[]
Some devices use active methods to measure (such as sonar, laser, or radar); others measure distance using trigonometry (stadiametric rangefinders and parallax, or coincidence, rangefinders). Older methodologies that use a set of known information, usually distances or target sizes, to make the measurement, have been in regular use since the 18th century.
Applications[]
Applications includes surveying, navigation, determining focus in photography, choosing a golf club, or accurately aiming a weapon.
Ballistics[]
Rangefinders may be used by military or law enforcement snipers as a means of finding the distance to the target in order to set up a "perfect shot".[1] If range is not known before the first shot, it may be necessary to walk the rounds in on the target, such as using tracer ammunition or observing splashes. The laser rangefinder is not always the best option though, as it sends out a light source that may give away the rangefinder's position.
Photography[]
A rangefinder camera is a camera fitted with a rangefinder which allows the photographer to measure the distance to the subject and thus take photographs that are in sharp focus. Most modern cameras have automatic-focus capabilities.
Forestry[]
Rangefinders are also used for surveying in forestry. Special devices with anti-leaf filters are used.
Virtual reality[]
Since the 1990s, rangefinders have been used in virtual reality systems to detect operator movements and locate objects.[2]
See also[]
Wikimedia Commons has media related to Rangefinders. |
References[]
- ↑ Farey, Pat and Spicer, Mark (2009) Sniping: An Illustrated History Zenith Press, Grand Rapids, Michigan, page 7, ISBN 978-0-7603-3717-2
- ↑ Kidd, Cory D. et al. (1999) "The aware home: A living laboratory for ubiquitous computing research" Lecture Notes in Computer Science 1670: pp. 191–198, doi:10.1007/10705432_17
Ballistics[]
- Army Test and Evaluation Command, Aberdeen Proving Ground Maryland (1969) Laser Rangefinders Ft. Belvoir Defense Technical Information Center, U.S. Army, Ft. Belvoir, Virginia, OCLC 227620848 20 pages (early history of the use of lasers in rangefinders)
- Gething, Michael J. (1993) Airborne Weapons: A Defence Handbook: A compilation of articles from Defence magazine over the last five years, charting the development of Airborne Weapons since 1987 Cardiff Publishing Company, Englewood, Colorado, ISBN 1-881289-11-7, 44 pages
- Infantry and Cavalry School (1905) Notes on rangefinders, compasses and on contouring with the Scale of Horizontal Equivalents (series: Infantry and Cavalry School Lectures 1902-1910) Staff College Press, U.S. Army, Fort Leavenworth, Kansas, OCLC 278057724, 35 pages
Photography[]
- Photographic and Imaging Manufacturers Association (1999) American national standard for photography (optics) : rangefinders and other focusing aids – performance specifications (revision and redesignation of "ANSI PH3.619-1988" as "ANSI/PIMA IT3.619-1998") American National Standards Institute, New York, OCLC 41501265, 14 pages
- Hicks, Roger and Schultz, Frances (2003) Rangefinder: Equipment, History, Techniques Guild of Master Craftsman, Lewes, United Kingdom, ISBN 1-86108-330-0
Surveying[]
- Ehlert, Detlef; Adamek, Rolf and Horn, Hans-Juergen (2009) "Laser rangefinder-based measuring of crop biomass under field conditions" Precision Agriculture 10(5): pp. 395–408
- Infantry and Cavalry School (1905) Notes on rangefinders, compasses and on contouring with the Scale of Horizontal Equivalents (series: Infantry and Cavalry School Lectures 1902-1910) Staff College Press, U.S. Army, Fort Leavenworth, Kansas, OCLC 278057724, 35 pages
- Whitehouse, J. C. (2005) "Further considerations of defocus rangefinders" Transactions of the Institute of Measurement and Control 27(4): pp. 297–316
Virtual space[]
- Ward, A.; Jones, A and Hopper, A. (1997) "A New Location Technique for the Active Office" IEEE Personal Communications 4(5): pp. 42–47
- Werb, J. and Lanzi, C. (1998) "Designing a positioning system for finding things arid people indoors" IEEE Spectrum 35(9): pp. 71–78
External links[]
- Range-Finding in the Army. How to use range-finders to get results: the erect and inverted types, Popular Science monthly, February 1919, page 118-120, Scanned by Google BooksPopular Science
- "No doubt, this best rangefinder is completely water proof and fog proof"'.
- "Distance calculator - Calculates the exact distance between places" [1]
- "Rangefinder Comparison - A National Forest Service document" [2]
- "Light Pulse Generator for rangefinder testing" [3]
The original article can be found at Rangefinder and the edit history here.