Abstract
This paper presents an iterative method for accurate particle detection in digital holographic measurement, and the performance evaluation is numerically carried out for particle depth measurement. Digital holography is a powerful and monocular technique for three-dimensional measurement to be applied to quantitative measurements of small objects, such as fuel spray and cluster of bubbles, in the industrial field of fluid engineering. In the present iterative method, virtual particles are introduced to be numerically placed at the first estimate of the particle positions in order to overcome conventional problems in which measured depth position has non-negligible error and particle detection itself is done by mistake. Then, virtual particles are adjusted in such a way that observed hologram patterns match those computed for virtual particles to improve measurement accuracy by regarding the converged solution as final measurement results. In numerical simulation, the effect of particle parameters on depth measurement accuracy is investigated by using multi-particle models for particle size 10〜50μm.
