title: Implementation of spatial overlap modulation nonlinear optical microscopy using an electro-optic deflector.
abstract: A spatial overlap modulation (SPOM) technique is a nonlinear optical microscopy technique which enhances the three-dimensional spatial resolution and rejects the out-of-focus background limiting the imaging depth inside a highly scattering sample. Here, we report on the implementation of SPOM in which beam pointing modulation is achieved by an electro-optic deflector. The modulation and demodulation frequencies are enhanced to 200 kHz and 400 kHz, respectively, resulting in a 200-fold enhancement compared with the previously reported system. The resolution enhancement and suppression of the out-of-focus background are demonstrated by sum-frequency-generation imaging of pounded granulated sugar and deep imaging of fluorescent beads in a tissue-like phantom, respectively.
authors.affiliation: Laser Technology Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan ; RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Isobe
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kawano
authors.forename: Akiko
authors.initials: A
authors.lastname: Kumagai
authors.forename: Atsushi
authors.initials: A
authors.lastname: Miyawaki
authors.forename: Katsumi
authors.initials: K
authors.lastname: Midorikawa
keywords: (180.2520) Fluorescence microscopy; (180.4315) Nonlinear microscopy; (190.4180) Multiphoton processes