Hyperspectral imaging with sub-cycle mid-infrared pulses


  • Takao Fuji ⋅ JP Toyota Technological Institute, Japan


Hyperspectral imaging is a technique that combines imaging and spectroscopy to map the distribution of chemical constituents. Mid-infrared (MIR) hyperspectral technique identifies and maps the chemical composition of an object through molecular vibration. However, the limited number of pixels and the low signal-to-noise ratio of MIR detectors prevent high performance of MIR hyperspectral imaging. To address this issue, up-conversion of the MIR ultrashort pulses to visible or near-infrared light is used. This approach improves the performance of MIR imaging since visible or near-infrared light can be detected with Si-based detectors, which have much higher performance than MIR detectors. In this talk, a new MIR hyperspectral imaging method based on sub-cycle MIR pulses is suggested. This method covers both the functional group and the fingerprint regions with high intensity. Unlike previous methods, the size of the image does not depend on the wavelength, which simplifies the calibration process. The sub-cycle MIR pulses are generated by using four-wave mixing through two-color filamentation. The MIR pulse passes through a sample and is sent to a GaSe crystal, while a chirped 800 nm pulse is also sent to the crystal. The sum frequency signal is then sent to a silicon-based hyperspectral camera and records hyperspectral images. The analytical ability of the new method is tested by imaging and mapping onion cells. The results show that the method has great potential for cell analysis since it can map the cell wall, cytoplasm, and nuclei, with the distribution of nuclei only visible in the MIR hyperspectral image.

About the Speaker

Takao Fuji, Toyota Technological Institute, Japan

Takao Fuji earned his Ph.D. degree in Engineering from University of Tsukuba, Tsukuba, Japan, in 1999. He began his career as a Research Associate at the University of Tokyo, where he worked from 1999 to 2002. During this time, he was awarded a JSPS Postdoctoral Fellowships for Research Abroad, which allowed him to broaden his knowledge and experience as a Guest Researcher at the Vienna University of Technology in 2002. In 2004, he was a Postdoctoral Researcher at the Max Planck Institute of Quantum Optics, Garching, Germany. He returned to Japan in 2006 to join RIKEN, Wako, as a Research Scientist, and he was promoted to Senior Scientist in 2008. In 2010, He was appointed as an Associate Professor at the Institute for Molecular Science in Okazaki, Japan. In recognition of his research contributions, he was subsequently offered a Professorship at Toyota Technological Institute in Nagoya, Japan in 2019. Throughout his career, his research interests have included the development of ultrashort pulse lasers, nonlinear optics, and ultrafast spectroscopy. He was awarded the Encouragement Award of the Optical Society of Japan in 1999, the Kondo Award of Osaka University in 2008, and the Laser Research Development Award of the Laser Society of Japan in 2015.



Article ID



Invited Presentations



How to Cite

T Fuji, Hyperspectral imaging with sub-cycle mid-infrared pulses, Proceedings of the Samahang Pisika ng Pilipinas 41, SPP-2023-INV-3E-01 (2023). URL: https://proceedings.spp-online.org/article/view/SPP-2023-INV-3E-01.