Invited by TIPC’s Future Youth Forum and Laboratory of Organic Nano Photonics and CAS Key Laboratory of Bio-Inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences (TIPC-CAS), Prof. Katsumasa Fujita from Graduate School of Engineering, Osaka University and his research team visited TIPC on August 29^th 2023.  

During the visit, Prof. Katsumasa Fujita and his team conducted a seminar and presented academic reports. The seminar was chaired by Prof. ZHENG Meiling. 

Firstly, Associate Prof. Yasuaki Kumamoto gave a report entitled as "High-throughput line-illumination Raman microscopy with multislit detection". In the presentation, Raman microscopy is reported as an emerging tool for molecular imaging and analysis of living samples, and Raman spectroscopic imaging technology has limited its application in life sciences due to the inability of rapid scanning in large areas. For this reason, he proposed a multislit ultrafast Raman spectral imaging method. A spectrophotometer equipped with a periodic array of confocal slits detects Raman spectra from a sample irradiated by multiple line illuminations. A comb-like Raman hyperspectral image is formed on a two-dimensional detector in the spectrophotometer, and a hyperspectral Raman image is acquired by scanning the sample with multiline illumination array. By irradiating a sample with 21 simultaneous illumination lines, high-throughput Raman hyperspectral imaging of mouse brain tissue was achieved, acquiring 1108800 spectra in 11.4 min. They also measured mouse kidney and liver tissue as well as conducted label-free live-cell molecular imaging. The ultrafast Raman hyperspectral imaging enabled by the presented technique will expand the possible applications of Raman microscopy in biological and medical fields. 

Subsequently, Prof. Katsumasa Fujita, whose research fields are super-resolution fluorescence and Raman microscopy, especially for applications related to biorephotonics, presented academic report entitled as "Super-resolution imaging and fabrication using nonlinear light-material interactions". In the presentation, Prof. Katsumasa Fujita pointed out that due to the lack of optical components and devices available in this deep UV region, its applications have been limited compared to visible light. Moreover, he introduced a methodology that aims to emulate the optical excitation properties of deep-ultraviolet light, focusing on two-photon excitation using visible laser pulses. By utilizing this methodology, it is possible to induce high energy excited states in materials using existing optics and visible pulse radiation. Experimental results show that this technique can be applied to two-photon excitation fluorescence microscopy, facilitating simultaneous high-resolution multicolor imaging of biological specimens. Furthermore, it has been shown that this two-photon excitation can activate the photopolymerization process of various materials without the need for conventional polymerization initiators. 

After giving reports, Prof. Fujita and his team discussed with the audiences. Researchers, postdoctoral fellows and graduated students attended the seminar.  

After the seminar, Prof. Fujita's team visited Laboratory of Organic Nano Photonics and had in-depth academic exchanges with researchers. During August 29^th and August 30^th, the research team between China and Japan have also held a seminar related to the "Green Environment-friendly Two-photon Micro/nano 3D Printing and Applications" project, including 6 oral presentations. Both sides have had a deep communication on the field of micro-nano photonics and micro-nano fabricating, and comprehensively discussed about the project plan. This seminar has played an important role in further strengthening the international cooperation. 

Prof. Katsumasa Fujita gave an academic report

Associate Prof. Yasuaki Kumamoto gave an academic report