We propose a new method for three-dimensional (3D) position measurement of nanoparticles using an in-line digital holographic microscope. The method improves the signal-to-noise ratio of the amplitude of the interference fringes to achieve higher accuracy in the position measurement by increasing weak scattered light from a nanoparticle relative to the reference light by using a low spatial frequency attenuation filter. We demonstrated the improvements of signal-to-noise ratio of the optical system and contrast of the interference fringes, allowing the 3D positions of nanoparticles to be determined more precisely.
© 2012 Optical Society of America
Original Manuscript: May 22, 2012
Revised Manuscript: August 27, 2012
Manuscript Accepted: August 29, 2012
Published: September 28, 2012
Quang Duc Pham, Yuichi Kusumi, Satoshi Hasegawa, and Yoshio Hayasaki, "Digital holographic microscope with low-frequency attenuation filter for position measurement of a nanoparticle," Opt. Lett. 37, 4119-4121 (2012)