Master these principles, you can better use the near-infrared spectrophotometer

Release Time:

2019-07-20 00:00


The light emitted by the light source of the near-infrared spectrophotometer is divided into two beams with equal energy and symmetry, one beam is the sample light passing through the sample, and the other beam is the reference beam as the reference. After entering the photometer through the sample chamber, the two beams of light are modulated at a certain frequency by the fan-shaped mirror to form an alternating signal.

The basic principle of near-infrared spectrophotometer:
The light emitted by the light source is divided into two beams of equal energy and symmetrical. One is the sample light passing through the sample and the other is the reference light. After the two beams enter the photometer through the sample chamber, they are modulated at a certain frequency by the fan-shaped mirror to form an alternating signal. The two beams are then combined into one, which alternately enters the monochromator through the entrance slit. The beam is projected parallel to the grating through an off-axis parabolic lens, and after passing through the slit, the dispersion is filtered with an optical filter. In addition to the higher-order spectrum, the detector is focused on the receiving surface by means of an ellipsoid mirror. The detector converts the above-mentioned AC signal into a corresponding electrical signal. After amplifying the voltage, the detector is sent to the A/D conversion unit. After computer processing, the infrared absorption spectrum from high wavenumber to low wavenumber was obtained.

Near-infrared spectrophotometer can be widely used in the analysis and determination of grains, oilseeds, food, animal feed, textiles, goods, industrial products, etc. It is mainly used for rapid non-destructive qualitative and quantitative analysis of the physical properties of liquids, sols without suspended solids, solids, powders, coatings, and other samples.

Features of near-infrared spectrophotometer:
Near-infrared qualitative and quantitative analysis software package, an external laptop computer is provided randomly, which can run Windows interface data acquisition, analysis and processing control software, and perform single-channel spectral scanning, self-checking and calibration, in-machine modeling, inspection and transfer models, sample analysis, and more. Channel operation, channel scan curve storage/display comparison/print report and other functions.
The scanning speed is less than 2min.
Equipped with imported PbS detector with cooling, the reflectivity of integrating sphere is more than 95%. Built-in sample cell structure, two kinds of sample cells are used for different samples.
The background of the rotary sample stage is fixed, and the sample can be rotated in all directions for multi-faceted measurement to solve the problem of uneven mixing.
Equipped with imported indium gallium arsenide detector. The sample cell with 4-connected cell structure is convenient for sample measurement.