Ocean Optics ARCoptix ANIR - Manual (Page 10)

1: Introduction
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Thanks to micromechanics technology and to the LGI concept, this instrument could have been made
compact enough to be portable and, because of the principle, easily upgradeable to any much larger
wavelength ranges. The limitation in wavelength range is not due to the concept, but due to the
photodetector that is used. In the standard model the detection of the interferogram is carried with one
single InGaAs photodiode. A single photodiode instead of a CCD line leads to lower noise and cost-
effective detection solutions, particularly in the near-IR. In addition, the choice of available detectors
is much larger than CCD and it is therefore easier to dedicate a detector to specific needs. There is no
risk of defective pixels as it is generally the case for conventional NIR spectrometers using arrays of
photodiodes.
As a result, this instrument is unrivaled and perfectly suited for detection in transmission like
measurement of gases and liquids. In particular, the absorption signatures of gases are measured with
high accuracy. The instrument is capable of recording 2 spectra per second but needs more time for
processing so that an effective measurement time results that might be larger.
The spectrometer provides a number of important benefits including the following:
 Laser controlled interferometer
 Choice of resolution
 Different amplification levels
 Data acquisition in 500 ms with an effective measurement time of 5 s
 A minimum power requirement - The spectrometer is driven by a standard USB 2.0 port
of a personal computer.
 The performance is unaffected by stray light
 The system is compact and lightweight.
The spectrometer is typically employed as a part of a system that includes a source and a sample
holder (a cuvette holder or a reflectance sphere). As an example, the spectrometer can be used with
the Tungsten Halogen Light Source and the Holder for 1-cm cuvettes. The source and cuvette holder
or reflectance sphere are acquired separately. As an alternative, the spectrometer can be directly
connected to the source to obtain the spectrum provided by the source).
The ARCoptix Near-Infrared Spectrometer can be used in a broad range of applications including
 Portable Field Measurements
 Laboratory Analyses
 Industrial Process Control
Product Description
The ARCoptix ANIR spectrometer is a lamellar grating spectrometer that combines the advantages of
Fourier Spectroscopy with micromechanics technology. The first gives exciting optical features while
the second leads to miniaturization and reliable operation. A lamellar grating interferometer is a
grating that operates in the zeroth order. This particular type of apparatus was invented by Strong [J.
Strong, and G. A. Vanasse, “Lamellar grating far-infrared interferometer”, J. Opt. Soc. Am. 50, 113-
118 (1960). A scheme of the principle is illustrated in the Fig. 1.2 below.