milirradianes

Miliradianes are a unit of angular measurement. One miliradian is equal to one thousandth of a radian. The radian is the SI unit of angular measure, defined as the angle subtended at the center of a circle by an arc equal in length to the radius. Therefore, one radian is approximately 57.3 degrees. Consequently, one miliradian is approximately 0.0573 degrees.

Miliradianes are frequently used in fields such as optics, artillery, and surveying. In optics, they are employed to measure small angles of divergence or beam spread. For instance, the angular resolution of a telescope or microscope might be expressed in miliradianes. In artillery and military applications, miliradianes are used for aiming and rangefinding. A common system, the "milliradian system," divides a circle into 6400 miliradianes. This system allows for quick calculations of range and deflection, as a target's apparent size in miliradianes multiplied by a constant factor (often 1 or 1000 depending on the context) provides an estimate of its range in meters or yards. Surveyors also use miliradianes for precise angle measurements in topographic mapping and land division. The small size of the miliradian unit makes it suitable for measuring the subtle changes in angle encountered in these disciplines.