High-speed line-scan confocal Raman microscope with enhanced diffraction efficiency. (15th November 2019)

• Record Type: Journal Article
• Authors: Xing, Jingchao; Kang, Sung-Hoon; Choi, Young-Man; Lee, Seungwoo; Yoo, Hongki
• Is Part Of: Measurement science & technology. Volume 31:Number 2(2020)
• Publication Date: 2019-11-15
• Subjects: confocal Raman microscopy -- spectrometer -- high-speed Raman imaging -- volume phase grating; Physical measurements -- Periodicals; Scientific apparatus and instruments -- Periodicals; Equipment and Supplies -- Periodicals; Science -- instrumentation -- Periodicals; Technology -- instrumentation -- Periodicals; Mesures physiques -- Périodiques; Physical measurements; Scientific apparatus and instruments; Periodicals; 502.87
• DOI: 10.1088/1361-6501/ab4b74
• Languages: English
• ISSNs: 0957-0233

Abstract

Abstract: Confocal Raman microscopy is commonly employed across different research fields because it allows for label-free sample investigation at high spatial resolution. However, the slow data acquisition speed of Raman microscopy limits its application for imaging large area samples. We developed a line-scan confocal Raman microscope to achieve parallel detection for high-speed data acquisition and proposed a dual mirror scan method to enhance the diffraction efficiency of the spectrometer. We used a Powell lens for the line illumination and demonstrated that it can provide a more uniform intensity distribution than a cylindrical lens. The spectrometer consists of a volume phase holographic grating and two scanning mirrors. Using the proposed dual mirror scan method can provide a high-resolution Raman spectrum at high efficiency over a wide spectral range. The system has a maximum spectral rate of 25 600 spectra s −1 and a theoretical spectral resolution of 1.2 cm −1 . With the parallel detection by the line illumination and the enhanced diffraction efficiency, we expect the proposed system can be used in a variety of applications that require a high spectral rate, such as wide-field Raman imaging.