NLS-Glossary

The numeric ratio of the bar’s height to the symbol’s length.                                                                                                                                                                                         

Aspheric lenses have non-spherical shapes, and have a more complex front surface, such as ellips, parabola, hyberbola, quadric, as well as toric which resembles a section of the surface of a rugby ball or a doughnut.

is the distance of the target to the sensor where the sensor can be guaranteed to have turned on. If a target approaches within the assured operating distance, you can be confident that the sensor will detect it. It is (0 ≤ sa ≤ 0.81 sn).

is a defect of optical lenses or a property of laser beams.
An optical system that exhibits astigmatism focuses two orthogonal axes of light at two different distances. In other words, astigmatism is an optical aberration that causes rays to propagate in two perpendicular planes with two different foci. The name of this aberration is derived from the Greek words ‘a’, meaning without, and ‘stigma’, meaning a spot or puncture.

Also referred to as start/stop transmission. Every character transmitted has special bits attached, telling the receiving device when the data begins and ends. Data is transmitted independently with no associated clock.

is not synchronized to any one time reference signal. A synchronous transmission does not use a common clock signal between the transmitter and receiver.