Optical amplifier is a device that amplifies an optical signal directly, without converting it to an electrical signal. It is used in optical communication and laser physics. The amplification is based on stimulated emission. The gain medium contains some atoms, ions or molecules in an excited state, which is stimulated by the signal light to emit more light into the same radiation modes.

In optical communications, an optical attenuator is used to reduce the power level of an optical signal. In optical attenuator used in fiber optic systems, the attenuation may depend on: the modal distribution in the optical signal; the absorptive, reflective, and scattering characteristics of the attenuator material; and the use of special coatings & films. The basic types of optical attenuators are fixed, step-wise variable, and continuously variable.

Optical Biometric Scanner forces perfect finger placement with each scan to produce an optimized image with maximum captured surface area. This fingerprint reader works well with dry, moist or rough fingerprints and is mountable to a 6″ adjustable, metal stand. It is ideal for use in high-throughput scanning environments. The drivers support windows xp, 2000, me, nt 4.0 and 98.

Optical brightner is a dyes, which absorb light in the ultraviolet and violet region of the electromagnetic spectrum, and re-emit light in the blue region. These additives are designed to enhance the appearance of colours in fabrics and on papers. They may also enhance or modify the appearance of white items. This creates a whitening effect by making materials look less yellow and by increasing the overall amount of light reflected to the eye. The most common class of chemicals with this property are the stilbenes. These chemicals are commonly part of laundry detergents to replace fluorescent whitening agents removed during washing and enhance the appearance of garments.