利用傅立葉轉換光譜影像技術快速測量金屬奈米粒子散射光譜

Abstract

本研究為架設ㄧ新的光學掃描系統，可大面積且快速的獲得玻片表面上金屬奈米粒子之光譜。 以傅立葉轉換光譜儀為基礎架設ㄧ多光譜影像系統。藉由改變Michelson干涉儀中兩道光束之光路程差產生光譜的資訊，利用電荷耦合器(CCD)擷取干涉強度，並表示成隨光路程差產生強度變化之干涉圖形(interferogram)，最後再對干涉圖形做傅立葉轉換獲得光譜。目前本光學系統已可獲得白光與不同filter產生之光譜以及兩種金屬奈米粒子之散射光譜。最終目標是希望能應用在以金屬奈米粒子所標記之基因晶片上，達到大面積、高解析度與快速檢測的目的。 最後與Berkeley大學Dr. Lee團隊所架設之多光譜影像系統做比較，其系統獲得300 µm 300 µm視野內所有金屬奈米粒子之光譜所需時間約為5分鐘；而本系統掃瞄視野大小465 µm 617 µm約為80秒。相較於Dr. Lee團隊，本系統在光譜解析度與掃描時間上都有改善的空間，需更努力以達到比他們更好的效果。

In this thesis, we present a novel optical scanning system for rapidly detecting scattering spectra of metal nanoparticles within large field of view on a slide. We constructed a hyperspectral imaging system based on Fourier transform spectrometry. Spectral information was generated by changing optical path difference between two beams in a Michelson interferometer. We utilized charge couple detector to record interference intensity as a function of the optical path difference (interferogram), and calculated the spectra with Fourier transformed the interferogram. By our optical system, we successfully obtained spectral information from white light source with different filters, and scattering spectra from two types of metal nanoparticles on glass slides. The ultimate goal is to apply our optical system to fast scan the scattering spectra of the metal nanoparticles used as optical tags in the microarray. For benchmarking, we compared our results with the multispectral microscopic imaging system built by Dr. Lee’s group at the university of California-Berkeley. Their measuring time of the scattering spectra of metal nanoparticles within the 300 µm x 300 µm field of view is 5 min and ours within the 465 µm x 617 µm field of view is approximately 80 seconds. Compared with Dr. Lee’s group, we have improvable performance in spectral resolution as well as scanning time, and need further effort to get beyond them.