A condition, function, or situation that applies to a point, rather than a line, an area, or a volume. Note: Examples of point functions are (a) the irradiance of an electromagnetic wave, (b) the refractive index on the endface of an optical fiber, (c) the pulse repetition rate at the endface of an optical fiber, (d) the electric field strength of an electromagnetic wave, such as a lightwave or a radio wave, and (e) the radiance on the emitting surface of a light-emitting diode. See also  condition,  electric field strength,  electromagnetic wave,  emit,  function,  irradiance,  light-emitting diode,  lightwave,  optical fiber,  optical fiber endface,  point,  pulse repetition rate,  radiance,  radio wave,  refractive index.