NLS-Glossary

Scanners read bar codes by using red light to recognize the contrast between the bars and spaces of the symbol. Colors that will scan effectively need to be chosen. Black bars against a white background are the safest choice, but other combinations will also work. Quiet Zone: The margins around the bar codes are vital, they enable the scanner to identify the beginning and the end of the bar code.

contains both donors and acceptors in the same crystal region which compensate for each other's effects. For example, if there are more donors than acceptors, Nd > Na, then some of the electrons released by donors are captured by acceptors and the net effect is that Nd – Na number of electrons per unit volume are left in the conduction band.

characterizes the propagation of a light wave in a medium in which there is a loss of energy, that is, the electromagnetic wave experiences attenuation, due to various loss mechanisms such as the generation of phonons (lattice waves), photogeneration, free carrier absorption, scattering, etc.

Composite codes like GS1 DataBar Composite Symbology are combining linear with 2D (stacked) symbologies. The advantage of such codes is that the linear code component encodes the most  important information. The 2D component is used for additional data. This separation ensures better  migration (e.g. with respect to scanning hardware) between linear and 2D technology.

is the scattering of a high energy photon by a "free" electron. The Compton effect is experimentally observed when an X-ray beam is scattered from a target that contains many conduction ("free") electrons such as a metal or graphite. When an X-ray photon interacts with a conduction electron in a metal it becomes deflected just as if it were a "particle" with a certain momentum p. The photon loses some of its energy to the electron and therefore suffers a reduction in the frequency from $𝜐$to $𝜐\text{'}$ From the Compton experiment, the momentum of the photon has been shown to conform to $p=\frac{h}{\lambda }$ De Broglie relationship.

Factory automation term where information is shared between computer aided design programs, materials resource planning (MRP) programs, and machine tools on the shop floor. Bar code data collection is an important part of a successful CIM implementation.