Height measuring instruments, referred to as altimeters and altimeters, are mainly used to measure the height of workpieces, as well as to measure shape and position tolerance dimensions, such as perpendicularity and straightness. They can also be used to measure depth, slot width, internal and external aperture, highest point, lowest point, flatness, angle, etc.

The altimeter is an instrument placed on a platform for uniaxial measurement, and the ideal placement platform is a granite platform. Altimeters, like other precision instruments, have certain requirements for the environment. Their optimal working environment is (20 ± 2) ℃, and the humidity is 55% - 65%. The purpose is to ensure the accuracy of data.