Integration of optical components on-chip for scattering and fluorescence detection in an optofluidic device

An optofluidic device is demonstrated with photonic components integrated onto the chip for use in fluorescence and scatter detection and counting applications. The device is fabricated by integrating the optical and fluidic components in a single functional layer. Optical excitation on-chip is accomplished via a waveguide integrated with a system of lenses that reforms the geometry of the beam in the microfluidic channel into a specific shape that is more suitable for reliable detection. Separate counting tests by detecting fluorescence and scattered signals from 2.5 and 6.0 μm beads were performed and found to show detection reliability comparable to that of conventional means of excitation and an improvement over other microchip-based designs.