title: Correction of depth-induced spherical aberration for deep observation using two-photon excitation fluorescence microscopy with spatial light modulator.
abstract: We demonstrate fluorescence imaging with high fluorescence intensity and depth resolution in which depth-induced spherical aberration (SA) caused by refractive-index mismatch between the medium and biological sample is corrected. To reduce the impact of SA, we incorporate a spatial light modulator into a two-photon excitation fluorescence microscope. Consequently, when fluorescent beads in epoxy resin were observed with this method of SA correction, the fluorescence signal of the observed images was ∼27 times higher and extension in the direction of the optical axes was ∼6.5 times shorter at a depth of ∼890 μm. Thus, the proposed method increases the depth observable at high resolution. Further, our results show that the method improved the fluorescence intensity of images of the fluorescent beads and the structure of a biological sample.
authors.affiliation: Central Research Laboratory, Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamakita-ku, Hamamatsu-City, Shizuoka-Pref., 434-8601, Japan.
authors.forename: Naoya
authors.initials: N
authors.lastname: Matsumoto
authors.affiliation: Central Research Laboratory, Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamakita-ku, Hamamatsu-City, Shizuoka-Pref., 434-8601, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Inoue
authors.affiliation: Department of Biochemistry, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya-City, Aichi-Pref., 466-8550, Japan.
authors.forename: Akiyuki
authors.initials: A
authors.lastname: Matsumoto
authors.affiliation: Department of Medical Spectroscopy, Applied Medical Photonics Laboratory, Medical Photonics Research Center, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu-City, Shizuoka-Pref., 431-3192, Japan.
authors.forename: Shigetoshi
authors.initials: S
authors.lastname: Okazaki
keywords: (170.2520) Fluorescence microscopy; (170.3880) Medical and biological imaging; (220.1000) Aberration compensation; (230.6120) Spatial light modulators