title: Fundamental imaging properties of transillumination laser computed tomography based on coherent detection imaging method.
abstract: The coherent detection imaging (CDI) method uses the optical heterodyne detection technique. CW and single frequency lasers having long coherence lengths are used to exploit the maximum advantages of heterodyne detection, such as high directionality, selectivity and sensitivity. The CDI method based on optical heterodyne detection enables selective filtering of the directional coherence-retaining emergent photons, which leads to image reconstruction from projections, similar to X-ray computed tomography (CT). So far we have demonstrated the advantages and capabilities of the measurement technique for transillumination optical computed tomography in biomedicine. Here, we investigate the fundamental imaging properties of CDI method, such as its high directionality and quantitativeness, with preliminary physical phantom experiments. The results show that the CDI method satisfies the requirements for CT reconstruction under the first order approximation, and enables quantitative measurements in the sense that the relationship between estimated and actual concentration retains a satisfactory linearity.
authors.affiliation: Faculty of Engineering, Yamagata University, 4-3-16 Jonan, Yonezawa 992-8510, Japan. yuasa@eat72.yz.yamagata-u.ac.jp
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Yuasa
authors.forename: Shinji
authors.initials: S
authors.lastname: Tanosaki
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Sasaki
authors.forename: Michiaki
authors.initials: M
authors.lastname: Takagi
authors.forename: Akira
authors.initials: A
authors.lastname: Ishikawa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Taniguchi
authors.forename: Balasigamani
authors.initials: B
authors.lastname: Devaraj
authors.forename: Takao
authors.initials: T
authors.lastname: Akatsuka
mesh_terms: D004867:Equipment Design; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation / Q000379:methods*; D019047:Phantoms, Imaging; D012680:Sensitivity and Specificity; D015898:Tomography Scanners, X-Ray Computed / Q000592:standards*