A micro digital in-line holographic particle tracking velocimetry (micro-DHPTV) system has been developed and applied to investigate the three-dimensional flow field in straight and Y-junction microchannels. The micro-DHPTV system comprises a cooled frame-transfer CCD camera and a double-pulsed laser. The processing algorithm introduced to evaluate the three-dimensional velocity is based on the combination of integrated cross-correlation and nearest neighbor matching algorithms, taking advantage of information from both the reconstructed particle field and the original holograms fringes patterns. Tests on simulated pairs of holograms show that the particles can be detected, located, and paired with high probability and accuracy. Results obtained in the straight and Y-junction microchannels show that the superimposed vector field is physically reasonable.
© 2011 Optical Society of America
Original Manuscript: June 29, 2011
Revised Manuscript: November 2, 2011
Manuscript Accepted: November 2, 2011
Published: December 5, 2011
Yingchun Wu, Xuecheng Wu, Zhihua Wang, Gerard Grehan, Linghong Chen, and Kefa Cen, "Measurement of microchannel flow with digital holographic microscopy by integrated nearest neighbor and cross-correlation particle pairing," Appl. Opt. 50, H297-H305 (2011)