Miniaturized spectrometers

R.V. Kruzelecky and A.K. Ghosh, Miniature spectrometers, in Handbook of Vibrational Spectroscopy, J.M. Chalmers and P.R. Griffiths (eds), vol 1, John Wiley Sons, New York, 2002. 

Kruzelecky, R.V. and Ghosh, A.K., Miniature Spectrometers. In Chalmers, J.M. and Griffiths, P.R. (eds), Handbook of Vibrational Spectroscopy, vol 1 John Wiley 8c Sons New York, 2002, pp. 423 35. Miller, C.E., Near-Infrared Spectroscopy of Synthetic and Industrial Samples. In Chalmers, J.M. and Griffiths, P.R. (eds), Handbook of Vibrational Spectroscopy, vol 1 John Wiley 8c Sons New York, 2002, pp. 196-211. 

Young MA, Stuart DA, Lyandres O, Glucksberg MR, Van Duyne RP. Surface-enhanced Raman spectroscopy with a laser pointer light source and miniature spectrometer. Canadian journal of Chemistry 2004, 82, 1435-1441. 

There is also a prototype of a Raman sensor module scheduled and in future a miniature spectrometer as shown in Figure 4.71 could be integrated [119]. 

Figure 2-33 Raman spectra of skim and whole milk measured with a miniature spectrometer. (Reproduced with permission from Raman Systems, Inc.)...

To gather additional information on a reaction, reaction calorimeters are often coupled with other analytical devices e.g., on-line FTIR, particle-sizing probes, turbidity probes, pH or other ion selective probes, etc.). Therefore, we developed a reaction cell that allows stirring, different dosing profiles for one or two reactants and can accommodate a small optical probe coupled to a miniaturized spectrometer, Figure 2. 

UV-Vis spectrometers have become much smaller in recent years due, in part, to the availability of hbre optics and very small grating monochromators. Miniature spectrometers have been available commercially since the 1990s. These spectrometers are often devised so that they can be interfaced to the sample and source via optical fibres. This enables difficult locations to be accessed, analytes of interest to be measured in the field and in-process and biological measurements to be taken. Some of these mini UV-Vis-NIR spectrometers can be nsed both in the laboratory and outside the laboratory for field testing. 

Figure 7.3 The USB4000 miniature spectrometer and a schematic of its optical system (Reproduced by permission of Ocean Optics).

T2. This can be measured directly from the FID length, as in simple miniature spectrometers, provided one does not need to resolve resonances with different shift. Full Fourier transform measurements are normally performed using a Carr-Purcell B sequence. In principle this is with... 

The i-LAB Visible Hand Held Analyzing Spectrometer from Microspectral Analysis, LLC (www.microspectralanalysis.com) is a portable miniaturized spectrometer powered by 3 AA batteries that covers the 400-700 nm region and weighs only 200 g (Figure 5.37). The instrument has a bandwidth of 4-7 nm, spectral resolution of 1.4 nm, and no moving parts. 

In situ ATR-FTIR spectroscopy also provides a unique way to analyze the surface of the target material during polishing. The information obtained can help to improve the understanding of material removal mechanism and other chemical processes in CMP, for example interactions of additives like amino acids or effects of the pH value. The presented technique using mSRE is applicable to all kinds of dielectric materials like Si nitride, low-k materials and even very thin metallic films. With the appropriate technical effort, it could be used for EPD as well as for miniaturized spectrometer systems as described in Section 14.3.2 in process control. 

A miniaturized spectrometer with CCD array for mounting on a printed circuit card inside the electronics has been developed for a film thickness monitor (18, 19). Light from the input fibre is focused by a 40 mm achromatic lens on to a blazed reflection grating with 300 lines/mm. A 50-element CCD array gives a spectral resolution of 10 nm. The spectrometer is 10 mm thick and 80 mm long. Spectrometers made by integrated optics have also been suggested (20). 

The present state of fibre-optic technology has provided miniaturized spectrometers, multiple sensing possibilities, remote measurement capabilities and even miniaturization of optical probes for incorporation into hypodermic needles for clinical and other biomedical measurements. This fast-moving technology offers many exciting possibilities for the future in the area of chemical sensing. 

XL Wang, DE Vaughn, V Pelekhaty, J Crisp. A novel miniature spectrometer using an integrated acousto-optic. Rev Sci Instrum 65 3653-3656, 1994. 

Miniature spectrometers find useful applications in plastics waste sorting. Chemiluminescence is used for the continuous determination of nitrogen oxides. 

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