title: Digital holographic microscope with low-frequency attenuation filter for position measurement of a nanoparticle.
abstract: We propose a new method for three-dimensional (3D) position measurement of nanoparticles using an in-line digital holographic microscope. The method improves the signal-to-noise ratio of the amplitude of the interference fringes to achieve higher accuracy in the position measurement by increasing weak scattered light from a nanoparticle relative to the reference light by using a low spatial frequency attenuation filter. We demonstrated the improvements of signal-to-noise ratio of the optical system and contrast of the interference fringes, allowing the 3D positions of nanoparticles to be determined more precisely.
authors.affiliation: Center for Optical Research & Education (CORE), Utsunomiya University, 7-1-2 Yoto, Utsunomiya 321-8585, Japan.
authors.forename: Quang Duc
authors.initials: QD
authors.lastname: Pham
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Kusumi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Hasegawa
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Hayasaki