RAMAN Spectrometer, Dual Channel, Portable, MAS 6083
A dual-channel Raman spectrometer is an advanced spectroscopic instrument designed to capture and process two independent spectral streams simultaneously—either from two distinct sample lines (via dual probes) or across combined/dual excitation wavelengths and detector paths—without channel crosstalk or the need for multiple bulky standalone spectrometers
Compact & Portable Dual-Laser Units: Systems like the DUPLA, integrate dual excitation wavelengths (e.g., 532 nm and 785 nm) into compact, low-noise portable form factors built for chemical identification, trace detection, and laboratory analysis
Versatile Wavelengths: Accommodates multiple laser sources (such as 532 nm, 785 nm, or 1064 nm FT-Raman) to suppress fluorescence or optimize scattering intensity depending on the material
Abstract
High-throughput on-line Raman detection has become commonplace in pharmaceutical and PAT. This has increased the demand for efficient, parallel spectral detection. In this work, a method of adjusting the optical structure parameters through multi-field theory is proposed to realize the detector accepting two spectral information from the light source at the same time. By combining two Raman probes and two customized Y-fibers, Raman spectra of two samples at the same laser power can be acquired simultaneously online. Compared with the multi-channel Raman spectroscopy detection system based on microscope device and multiple Raman spectroscopy coupling system, the measurement time and cost are greatly reduced. Thus, dual-channel Raman spectroscopy detection devices provide a cost and time-saving method for modern high-throughput on-line Raman detection.
Introduction
Spatially offset Raman spectroscopy facilitates the direct acquisition of Raman spectra for solid and liquid samples contained within vessels. Similarly, surface-enhanced Raman spectroscopy and conventional Raman assays offer the capability to measure both partially solid and liquid samples in containers. Due to the versatility and accuracy of Raman spectroscopy, these techniques have an important place in pharmacopoeias around the world. [1], [2], [3], [4], [5], [6], [7], [8] This method offers several advantages, including speed and the elimination of prior sample preparation and destruction. Additionally, it can be utilized for on-line process detection during drug synthesis. Online Raman detection technology has become one of the most widely used methods in the process of drug synthesis, [9], [10] particularly for real-time monitoring of active pharmaceutical ingredient reactions, synthesis, crystallization, granulation, mixing, drying, lyophilization, extrusion, encapsulation, and coating. The measurement results are utilized to analyze and control the manufacturing processes of pharmaceutical products in a timely manner, serving as a powerful tool for the biological, pharmaceutical, chemical, and food industries. Raman spectroscopy has emerged as a powerful analytical technique characterized by its high chemical selectivity and remarkable versatility. [11], [12], [13], [14], [15] In this work, we propose a novel optical system illustrated in Fig. 1. This system adjusts the parameters of the optical structure based on the multiple field-of-view theory, [16] enabling a single detector to simultaneously receive two spectral information from the light source. The system utilizes two Raman probes in conjunction with a Dual-Channel Raman Spectrometer for real-time Raman analysis of solid samples in petri dishes. This technology, based on the Czerny-Turner structure and utilizing the multi-field-of-view theory, can simultaneously detect two different monitoring points. Each point possesses a complete Raman spectrum, enabling dual-channel online simultaneous detection.
Both traditional Raman spectroscopic detection and hyperspectral Raman spectroscopic detection techniques are based on the Raman scattering principle. Hyperspectral Raman imaging spectrometers boast the advantage of superior spatial resolution when capturing Raman signals, which facilitates Raman imaging and spectral analysis of samples in tiny regions or intricate multiphase systems. However, they often come with a higher price tag and necessitate additional time to garner a comprehensive Raman image replete with complete spatial information. Most current multi-channel Raman spectrometers predominantly utilize a combination of a hyperspectral imaging Raman spectrometer and a microscope. An alternative configuration involves a hyperspectral Raman spectrometer and multiple probes. The light is focused with a diffractive optics, [17], [18], [19] scanning lenses, [20], [21], [22], [23], [24], [25] micro-lens arrays [26] or beam splitters [27] to several points under the microscope objective. Another method is by combining multiple probes with a hyperspectral spectrometer [28], [29], [30] or multiple Raman spectrometers, [31], [32] where different probes focus on different focal points. The Raman-scattered light from these points is collected and rearranged mainly by fiber optical arrays, which are then introduced into the hyperspectral spectrometer or multiple Raman spectrometers. [33], [34], [35], [36], [37] The optical fibers are rearranged along the slit of the spectrometer, enabling it to measure each point concurrently. The Raman spectrum is reorganized by reading pixel points across various rows and columns to create a hyperspectral image. However, hyperspectral cameras are costly, and the instrumentation is bulky, immobile, and not well-suited for online inspections.
Therefore, we propose a method to adjust the optical structure parameters through the multi-field-of-view theory to realize that the detector accepts two spectral information from the light source at the same time. The combination of two Raman probes and two y-fibers enables the simultaneous online acquisition of two Raman spectra at the same laser power. The laser is focused onto the sample plane through the y-fiber and the probes. The Raman-scattered light is collected through the split-beam end of the fibers and directed into the multi-field Raman spectrometer through the combined beam end of the y-fiber. The optical fibers are rearranged along the slit into the spectrometer, and the detector can collect Raman spectral information from different channels simultaneously. Compared to a hyperspectral camera or multiple detectors, an area imaging detector offers several advantages: cost savings, portability, suitability for integration into online inspection equipment, and potential for miniaturization.