Project/Area Number |
10650396
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Measurement engineering
|
Research Institution | HOKKAIDO UNIVERSITY |
Principal Investigator |
IWAI Toshiaki Hokkaido Univ., Reseat Institute for Electronic Science, 電子科学研究所, 助教授 (80183193)
|
Project Period (FY) |
1998 – 1999
|
Project Status |
Completed (Fiscal Year 1999)
|
Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 1999: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1998: ¥2,500,000 (Direct Cost: ¥2,500,000)
|
Keywords | Diffusing light topogaphy / Multiple backscattering / Monte Carlo simulation / Photon diffusion theory / Optical path-length distribution / Optical CT / Visualization of blood vessel / Deconvolution / 拡散光 / トポグラフィ / 血管造影 |
Research Abstract |
The purpose of the research project is to establish a diffusing light topography in a surface profiling of an absorber embedded in a strongly scattering medium. The relation between a backscattered intensity distribution and an optical path-length distribution was first studied by means of Monte Carlo simulations. The fairly well images for a slab-plane, stir-like, and modified-pyramidal absorbers were reconstructed in experiments and simulations and, therefore, the availability of the proposed method was confirmed. The deconvolution method was introduced to the formation of the backscattered intensity distribution at the boundary to improve the quality of the blurred image. A portion of the edge in the blurred image was sharpened by using the point spread function estimated by the Monte Carlo simulation for the point-like absorber placed at the shallowest depth. Finally, the optical path-length distribution was derived theoretically from a photon diffusion equation. The new relation between the depth of the absorber and the maximum path-length was obtained, by which the image was reconstructed with the same accuracy as the simulation. Throughout this research project, we are convinced that the proposed diffusing light topography leads us to the visualization of the blood vessel map and the tumor under the skin.
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