title: PDMS 2D optical lens integrated with microfluidic channels: principle and characterization.
abstract: In this paper, the fabrication and characterization of PDMS 2D-optical lenses are reported. These lenses are designed in order to improve the performance of fluorescent spectroscopy detection performed on a portable chip using optical fibers. The fabrication process of the PDMS layer is first detailed, and the patterns are then checked with a SEM. By comparing various interfacial structures, it is shown that the beam properties of the light coming out from the fiber can be modified depending on the lens curvature radius. As a consequence, for a constant dye concentration, the use of such lenses can increase the intensity of fluorescent response close to the fiber or far from the fiber, compared to the same design with a flat interface. This excitation improvement corresponding to a stronger response from the dye then consequently leads to around three times higher sensitivity of the on-chip detection method for fluorescent spectroscopy.
authors.affiliation: Institute of Industrial Science, Universuty of Tokyo, 4-6-1 Komaba, Meguro-ku, 153-8505, Tokyo, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Camou
authors.forename: H
authors.initials: H
authors.lastname: Fujita
authors.forename: T
authors.initials: T
authors.lastname: Fujii
mesh_terms: D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D004867:Equipment Design; D005336:Fiber Optic Technology; D007909:Lenses; D044085:Microfluidics / Q000295:instrumentation / Q000379:methods; D055100:Optical Fibers; D013050:Spectrometry, Fluorescence / Q000295:instrumentation / Q000379:methods
chemical_list: D004129:Dimethylpolysiloxanes