Near-IR spectrometer

Quality control, pharmaceutical product identity checks, and quantification are important fields in the broad application of the different spectroscopic methods. There are many spectroscopic aspects, e.g., concerning sample preparation, influences from different accessories, and possibly spectrometer effects, which certainly influences quantitative measurements. The latter problems could be solved using calibration transfer between different spectrometer types, for example, a scanning and an FT-near-IR spectrometer. 

Because many atmospheric constituents absorb efficiently in the infrared spectral region, the development of an IR multichannel spectrometer was important to complement our near IR spectrometers. Originally, the pyroelectric vidicon (16) was selected as the IR image devices. This imager is a thermal rather than photon detector, and as such detects only variations... 

A. M. Bartz, Near-IR Spectrometer Analyzer, Instruments and Control Systems 33, 458, Mar. 1960. 

See also Near-IR Spectrometers Vibrational CD, Applications Vibrational CD Spectrometers Vibrational CD, Theory. 

The idea of a spectrometer dedicated to near-IR spectroscopy is relatively recent, and the early commercial near-IR instruments were simply UV-visible (or mid-infrared) spectrometers fitted with an additional detector and occasionally a second grating blazed for the near-IR. This equipment provided the basis for the pioneering work of Kermit Whetzel and Wilbur Kaye, who were largely responsible for laying the foundation of analytical near-IR spectroscopy. The development of modern near-IR instrumentation was spurred by research at the US Department of Agriculture Karl Norris discovered that no commercial spectrometer of the time could provide diffuse reflectance measurements of the quality he required, and developed his own computerized near-IR spectrometer... 

It is easy to find a pair of near-IR spectrometers that would not be recognizable as belonging to the same species even placed side by side. This diversity has arisen largely as a result of the tremendous variety of applications, with each unique application satisfied by a unique set of design and performance characteristics. 

Some of the spectral criteria that characterize and differentiate near-IR spectrometers are wavelength accuracy and precision photometric accuracy, precision, and linearity signal-to-noise and resolution (or spectral bandwidth). Among these, the attributes... 

Practical considerations almost always play a role in choosing a near-IR spectrometer, reflecting specific demands that may be placed by a specific application. Among these considerations are size and/or portability speed susceptibility to extreme (e.g. industrial) environments cost measurement type and flexibility (e.g. can the spectrometer be used only for transmittance measurements, or are reflectance and/ or fibre optic measurements feasible ). Manufacturers consider all of these factors. For example, it is common to find commercial instrumentation housed in enclosures that are ruggedized to meet specific industry standards (National Electrical Manufacturers Association - NEMA). 

The following sections are intended to illustrate the measurement principles for commercial near-IR spectrometers, and to provide an understanding of the strengths inherent in each design. Because near-IR spectroscopy and chemical analysis are inextricably linked, particular emphasis is placed on features relevant to this application. 

Analytical Spectral Devices Boulder CO USA Near IR spectrometers... 

Perten Instrumerrts Reno, NV Hbi emount Anaiyiicai Orrville, OH USA Near IR spectrometers near I n speurm nuitii [ s... 

See also Calibration and Reference Systems (Regulatory Authorities) FT-Raman Spectroscopy, Applications IR Spectrometers IR Spectroscopy, Theory Near-IR Spectrometers Raman Spectrometers. 

See also Light Sources and Optics Near-IR Spectrometers Raman Spectrometers. 

See also EPR, Methods Fluorescence Microscopy, Applications Fluorescent Molecular Probes Hole Burning Spectroscopy, Methods Laser Magnetic Resonance Laser Applications in Electronic Spectroscopy Laser Spectroscopy Theory Light Sources and Optics Luminescence Theory Near-IR Spectrometers Raman Optical Activity, Applications Symmetry in Spectroscopy, Effects of UV-Visible Absorption and Fluorescence Spectrometers Zeeman and Stark Methods in Spectroscopy, Applications. 

See also ATR and Reflectance IR Spectroscopy, Applications Chromatography-IR Methods and Instrumentation Far IR Spectroscopy, Applications Forensic Science, Applications of IR Spectroscopy High Resolution IR Spectroscopy (Gas Phase), Applications High Resolution IR Spectroscopy (Gas Phase), Instrumentation Hydrogen Bonding and other Physicochemical Interactions Studied By IR and Raman Spectroscopy Industrial Applications of iR and Raman Spectroscopy iR and Raman Spectroscopy of inorganic. Coordination and Organometaiiic Compounds iR Spectrometers iR Spectroscopy Sampie Preparation Methods Medicai Science Appii-cations of iR Near iR Spectrometers Poiymer Appii-cations of iR and Raman Spectroscopy Surface Studies By iR Spectroscopy. 

Spectroscopy, Theory Near-IR Spectrometers Surface Studies by IR Spectroscopy. 

See also Atomic Absorption, Theory Eiectromag-netic Radiation EPR, Methods EPR Spectroscopy, Appiications in Chemistry EPR Spectroscopy, Theory Far-iR Spectroscopy, Appiications High Resoiu-tion iR Spectroscopy (Gas Phase) instrumentation iR Spectroscopy, Theory Laser Spectroscopy Theory Near-iR Spectrometers Rotationai Spectroscopy, Theory Spectroscopy of ions Zeeman and Stark Methods in Spectroscopy, Appiications Zeeman and Stark Methods in Spectroscopy, instrumentation. 

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