title: Detection of microbubble position by a digital hologram.
abstract: This paper reports on a new technique of measurements of microbubble position in three dimensions with high time-resolution. The technique is based on micro digital holographic particle tracking velocimetry. In this technique, an intensity profile is constructed from a holographic image of a microbubble where the profile results in showing two peaks. The distance between the two peaks appears to relate to the size of the microbubble's diameter. The three-dimensional position of the bubble can be detected by the center of the two peaks and the center point of the bubble image focused by a digital hologram. We also theoretically obtained the intensity profile of a microbubble by considering a refraction of light on a bubble surface to a ring-shaped aperture model. The theoretically obtained distance between the two peaks is found to be in good agreement with the values obtained experimentally.
authors.affiliation: Department of Applied Electronics, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan. satake@te.noda.tus.ac.jp
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Satake
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Yonemoto
authors.forename: Tadashi
authors.initials: T
authors.lastname: Kikuchi
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Kunugi