Detectors

A detector is the device that registers, or detects, a signal, stimulus, interference, or a physical parameter of interest.

Detector is the core of any acquisition. Detectors include hardware device(s) that is sensitive to specific phenomenon and the interface between the hardware and the operator, including A/D converters.

Depending on the implementation, most detectors can be either single-channel or multi-channel. A simple temperature or pressure sensor is an example of a single-channel detector, while an array of such sensors may be organized as a multi-channel detector. Light measurement in a scanning spectrometer is done by a single-channel photomultiplier. Many modern spectrometers incorporate photodiode arrays or CCD arrays, which are multi-channel.

type	sensors	measurement
single-channel	one sensor	single measurement at a time, unrelated to other detectors
multi-channel	array or matrix of sensors	multiple measurements simultaneously; data from sensors relate by phenomenon

In many cases a single-channel detector can be used to record a multi-channel signal. Scanning UV-Vis spectrometers are the most common examples where a single photomultiplier or a photodiode sensor records light intensity as wavelength is continuously scanned by turning diffraction grating. Examples of scanning detectors used in this group include mid-frequency Bruker FTIR spectrometer (MCT or DTGS detectors) and low-frequency Bomem FTIR spectrometer (Si-bolometer detector).

Pressure and temperature sensors are typically used in this group as single-channel detectors. While there may be several such sensors that are being used concurrently in acquisition and produce a multi-channel data, each sensor in essence behaves as a separate detector.

Some detectors used in our group:

brand	parameter	type	configuration	details	XDSoft
Jobin Yvon CCD's	UV to near-IR radiation	CCD	imaging	256×1024 and 800×2000 two-dimensional matrices of sensors	yes
Ocean Optics SD2000	UV to near-IR radiation	CCD	linear	2048 sensors	yes
Hewlett Packard 8453	UV to near-IR radiation	photodiode	linear	910 sensors	no
Bruker Equinox	mid-IR radiation	MCT or DTGS	scanning	one sensor, Fourier-transformation of time into frequency	no
Bomem	far-IR radiation	Si-bolometer	scanning	one sensor, Fourier-transformation of time into frequency	no
Lakeshore & Cryocon	temperature	thermocouple, thermistor, Pt, Si-Diode etc.	single	1-4 individual sensors, also a controller	yes
Omegadyne & Newport	pressure	load cell	single	3 sensors via iSeries process monitors,	yes

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