title: A method for detecting forward scattering signals on-chip with a photonic-microfluidic integrated device.
abstract: A photonic integrated microfluidic device is demonstrated to perform optical excitation and forward scatter collection all on-chip in a planar format. Integrated on-chip optics formed a tailored beam geometry for optimal excitation of particles while a special design modification allowed for on-chip forward collection with the beam shaping capabilities. A notch was placed in the lens system that caused a dark spot on the facet of a collection waveguide while not affecting the beam geometry at the point of interrogation. The modified device with the ability to form a 10 μm beam geometry was demonstrated to detect the forward scatter from blank 5 μm diameter polystyrene beads. Free-space collection of side scatter signals was performed simultaneously with the on-chip collection and the designs demonstrated and enhanced SNR while the reliability of detection was determined to be appropriate for many applications. Excellent performance was confirmed via a false positive rate of 0.4%, a missed events rate of 6.8%, and a coincident rate of 96.3% as determined between simultaneously performed free-space and on-chip detection schemes.
authors.affiliation: Department of Engineering Physics, McMaster University, Hamilton, Ontario L8S 4L7, Canada.
authors.forename: Benjamin R
authors.initials: BR
authors.lastname: Watts
authors.forename: Zhiyi
authors.initials: Z
authors.lastname: Zhang
authors.forename: Chang-Qing
authors.initials: CQ
authors.lastname: Xu
authors.forename: Xudong
authors.initials: X
authors.lastname: Cao
authors.forename: Min
authors.initials: M
authors.lastname: Lin
keywords: (130.3120) Integrated optics devices; (130.5460) Polymer waveguides; (170.0170) Medical optics and biotechnology; (230.3990) Micro-optical devices; (290.2558) Forward scattering