Frequently Used Abbreviations of Sensor Technologies at a Glance

In alternating current (AC) the movement of electric charges periodically reverses direction.

Analog-to-digital converter.

Angle Of Incidence, see figure.

Anti-reflection coating is a single or multi layer coating without filter function to improve transmittance of windows or filters.

Multi channel detectors with common cap hole for all spectral channels and internal splitting into two or four channels.

Multi channel detectors with one cap hole per spectral channel each.

Current mode, an operation mode of pyroelectric detectors, especially used in types with integrated operational amplifier, like the LME-335.

Complementary metal-oxide-semiconductor: A technology for constructing integrated circuits.

This is a possible form of specification of the NBP, it is the wavelength at 5% or 50% of peak transmission on both flanks (left side Cut-on, right side Cut-off).

Center wavelength is the center of the pass band of a band pass filter, see figure.

Specific Detectivity: Figure of merit used to characterize performance, equal to the reciprocal of noise equivalent power (NEP), normalized to square root of unit area and unit bandwidth, see figure.

In direct current (DC), the flow of electric charge is only in one direction.

Electrostatic discharge: Through improper handling the ESD can cause detector damage.

Here: Field of view of IR detector. It is mostly limited by the detector's aperture hole, see figure.

Fabry-Pérot filter

Free spectral range: the spacing in optical frequency or wavelength between two successive reflected or transmitted optical intensity maxima or minima of an interferometer.

Full width half measure: Another vocable for HPBW.

Half power Bandwidth: Bandwidth at 50% of peak transmittance, see figure.

Infrared: radiation with a wavelength between (0.78 and 1,000) µm.

Junction field effect transistor: special low current and voltage noise transistor for impedance transformation.

Long Wave Pass is a filter with cut-on wavelength but no specification of cut-off. All wavelength longer than cut-on are able to pass, all wavelengths below are blocked. Opposite from SWP (Short Wave Pass), see figure.

Mid Infrared, radiation with a wavelength between (3 and 50) µm.

Micro-Opto-Electro-Mechanical Systems: A special kind of Micro-Electro-Mechanical Systems (MEMS) merged with Micro-optics.

Mean time to failure, which measures average time to failures with the modeling assumption that the failed system is not repaired. For InfraTec’s single and dual channel detectors the MTTF amounts more than 300 years, for quad channel detectors about 100 years.

Narrow Band Pass is a band pass filter with a bandwidth of < 10% of the center wavelength, see figure.

Non Dispersive Infrared Radiation.

Noise equivalent power: At a given modulation frequency, operating wavelength and effective noise bandwidth, the NEP is the radiant power that produces a signal-to-noise ratio of unity at the output of the optical detector.

Note: Some manufacturers and authors define NEP as the minimum detectable power per square root bandwidth. When defined this way, NEP has the units of watts per (hertz)1/2. Therefore, the term is a misnomer, because the units of power are watts.

Near Infrared: Radiation with a wavelength between (0.78 and 3) µm.

Operational amplifier.

Brandmark of InfraTec for state-of-the-art multi channel detectors in buttonhole and beam splitter design.

Current responivity: short-circuit current of pyroelectric element divided by incident radiant power.

Voltage responsivity: output signal voltage divided by incident radiant power.

Signal-to-noise-ratio.

Temperature coefficient [%/K or ppm/K].

Transistor Outline: Specifies a transistor's package, see figure.

Voltage noise normalized at 1Hz bandwidth, also known as noise density.

Ultraviolet (radiation), see figure

Human visible radiation with a wavelength between (0.38 and 0.78) µm.

Voltage mode, a conventional operation mode of pyroelectric detectors, for example used in LIE-302.

Wide Band Pass is a band pass filter with a bandwidth of > 10 % of the center wavelength, see figure.