Search results
Results from the WOW.Com Content Network
Stereoscopic rangefinder atop the bridge of the German cruiser Admiral Graf Spee Portable stereoscopic rangefinder with binoculars from WWII. A stereoscopic rangefinder or stereoscopic telemeter [1] is an optical device that measures distance from the observer to a target, using the observer's capability of binocular vision.
Range (r) = approximate height of object (h) × (1000 ÷ aperture in milliradians (a)) r = h(1000/a) → where r and h are identical units, and a is in milliradians. r = h/a → where r and h are identical units, and a is in radians. The above formula functions for any system of linear measure provided r and h are calculated with the same units.
Rangefinders may be used by users of firearms over long distances, to measure the distance to a target to allow for projectile drop. [10] Until the development of electronic means of measuring range during the Second World War, warships used very large optical rangefinders—with a baseline of many meters—to measure range for naval gunnery.
A long-range laser rangefinder is capable of measuring distance up to 20 km; mounted on a tripod with an angular mount. The resulting system also provides azimuth and elevation measurements. A laser rangefinder , also known as a laser telemeter , is a rangefinder that uses a laser beam to determine the distance to an object.
The radius or radial distance is the Euclidean distance from the origin O to P. The inclination (or polar angle) is the signed angle from the zenith reference direction to the line segment OP. (Elevation may be used as the polar angle instead of inclination; see below.)
A height finder radar is a type of 2-dimensional radar that measures altitude of a target. The operator slews the antenna toward a desired bearing , identifies a target echo at a desired range on the range height indicator display, then bisects the target with a cursor that is scaled to indicate the approximate altitude of the target. [ 7 ]
While a radian is defined as an angle on the unit circle where the arc and radius have equal length, a milliradian is defined as the angle where the arc length is one thousandth of the radius. Therefore, when using milliradians for range estimation, the unit used for target distance needs to be thousand times as large as the unit used for ...
The concept of the position angle is inherited from nautical navigation on the oceans, where the optimum compass course is the course from a known position s to a target position t with minimum effort.