As the core equipment for material structure analysis and composition detection, the scanning mode of infrared spectrometer directly determines the analysis efficiency, data accuracy, and experimental applicability. Quick scanning is a common measurement mode.

Quick Scan（Rapid Scan）Based on Fourier Transform Infrared Spectroscopy（FTIR）The principle of the interferometer is to generate a continuously changing optical path difference through the uniform and continuous motion of the moving mirror, and then obtain an interferogram containing full band information. Its core advantage lies in“quick”——A single scan can cover the entire infrared band (usually4000-400 cm ⁻¹）The scanning speed can reach0.1-10 cm ⁻¹/Seconds, even faster. Due to the characteristics of continuous motion, fast scanning signal acquisition has“real-time”However, due to the influence of mirror motion accuracy and mechanical vibration, in high-resolution (such as...)< 0.1 cm ⁻¹）Signal distortion may occur in time-resolved experiments.

The core value of fast scanning lies in “Effective coverage”and“real-time monitoring”When the experimental requirements focus on routine analysis, batch testing, or real-time tracking of dynamic processes, its advantages are particularly prominent.

（1） Qualitative and quantitative analysis of conventional substances: batch testing “effective tool”

In routine laboratory analysis, if it is necessary to collect infrared spectra of a large number of samples (such as chemical products, drugs, and food additives) to achieve qualitative composition (such as determining the presence of functional groups) or quantitative content (such as detecting impurity concentration), rapid scanning is the primary choice. This type of experiment usually does not require high resolution (conventional resolution is4 cm⁻¹or2 cm⁻¹）And efficiency needs to be taken into account——Fast scanning can take as short as a few seconds or even milliseconds per scan, and with the help of an automatic sampling system, hundreds of samples can be analyzed in a day. For example, infrared identification of active pharmaceutical ingredients in drug production can be achieved through rapid scanning10 Complete the spectral collection of a sample within seconds to meet the batch testing requirements of the production line.

（2） Real time monitoring of dynamic processes: capturing “Instantaneous changes”

When it is necessary to track chemical reactions, phase transitions, or adsorption/Rapid scanning during real-time changes in dynamic processes such as desorption“real-time”crucial. For example, when studying the thermal aging process of polymers, real-time infrared spectra of polymers at different temperatures can be collected through rapid scanning to observe hydroxyl groups（-OH）Or carbonyl（C=O）Analyze the aging rate based on changes in the strength of functional groups; For example, in catalytic reactions, rapid scanning can capture the generation and disappearance of intermediates on a millisecond scale, providing dynamic data for the study of reaction mechanisms. The key requirement for this type of experiment is“Quickly capture changes”The continuous acquisition mode of fast scanning can avoid problems caused by step size stagnation“Time gap”Ensure the continuity of data.

（3） On site in-situ analysis: portable scene analysis “Adaptation selection”

In field geological exploration, environmental emergency detection and other on-site scenarios, portable infrared spectrometers usually adopt fast scanning mode. On the one hand, on-site analysis requires high efficiency (quick data acquisition is needed to determine the type of pollutant or mineral composition); On the other hand, the mechanical stability of portable devices is limited, and the continuous motion of the fast scanning mirror is more adaptable to the on-site environment (such as slight vibrations), while the step-by-step stop mode of step scanning may cause signal fluctuations due to environmental interference. For example, in on-site detection of heavy metal pollution in soil, rapid scanning can be used 1 Complete the infrared spectrum collection of soil samples within minutes to quickly determine the presence of carbonates（CO₃²⁻）Or characteristic peaks of organic matter, providing a basis for subsequent processing.