Accurate size measurement of needle-shaped particles using digital holography

Taslima Khanam, Mohammad Nurur Rahman, Arvind Rajendran, Vinay Kariwala, Anand K. Asundi

Research output: Contribution to journalArticlepeer-review


In this paper, a digital holography based method is proposed to accurately measure the length and orientation of the needle-shaped particles in solution. The method involves recording of the hologram and numerical reconstructions (focusing) of the hologram at several depths. An image analysis routine is then used to determine the length, location and orientation of the particles from the reconstructed images without any a priori information about the orientation of particles. The performance of the method is verified using a single fiber with known size and orientation. Subsequently, the proposed method is applied to a suspension of fibers, where the length measurements are found to be in good agreement with the true values. This proposed technique can overcome the shortcoming of existing 2D imaging tools, which can provide only the projected lengths of randomly oriented particles.

Original languageEnglish
Pages (from-to)2699-2706
Number of pages8
JournalChemical Engineering Science
Issue number12
Publication statusPublished - 15 Jun 2011
Externally publishedYes


Dive into the research topics of 'Accurate size measurement of needle-shaped particles using digital holography'. Together they form a unique fingerprint.

Cite this