- 一般社団法人 日本機械学会
- 日本機械学会論文集 (ISSN:21879761)
- vol.81, no.823, pp.14-00348-14-00348, 2015 (Released:2015-03-25)
This paper presents a normalized deconvolution approach for a digital holographic particle measurement in order to decrease the elongation of the reconstructed particles along the depth direction. The performance of this approach is evaluated using numerical simulations, and its practicality is experimentally demonstrated. In the numerical simulations, the performance is evaluated mainly based on the cross-correlation between the true distribution and the deconvolution results. Tests were carried out for two types of recording systems and three kinds of reconstructed information. The results indicate that the most accurate particle images were obtained using the phase-shifting observation method and reconstructed quantities that contain phase information, such as the complex amplitude. Furthermore, the RMS error in the particle depth position is found to be improved especially for higher number density within the particle distribution. Experimental measurements with standard particles confirm that particle elongation along the depth direction can be successfully suppressed using the normalized deconvolution method. The experimental results thus confirm that this method is useful for real particle measurements.