title: Optofluidic lens with low spherical and low field curvature aberrations.
abstract: This paper reports an optofluidic lens with low spherical and low field curvature aberrations through the desired refractive index profile by precisely controlling the mixing between ethylene glycol and deionized water in an optofluidic chip. The experimental results demonstrate that the spherical aberration is reduced to 19.5 μm and the full width at half maximum of the focal point is 7.8 μm with a wide divergence angle of 35 degrees. In addition, the optofluidic lens can focus light at different off-axis positions on the focal plane with Δx' < 6.8 μm and at opposite transverse positions with |Δy - Δy'| < 5.7 μm. This is the first demonstration of a special optofluidic lens that significantly reduces both the spherical and field curvature aberrations, which enhances the focusing power and facilitates multiple light source illumination using a single lens. It is anticipated to have high potential for applications such as on-chip light manipulation, sample illumination and multiplexed detection.
authors.affiliation: School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798. eaqliu@ntu.edu.sg ewser@ntu.edu.sg.
authors.forename: H T
authors.initials: HT
authors.lastname: Zhao
authors.affiliation: School of Physics and Technology, Wuhan University, Wuhan 430072, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Yang
authors.affiliation: School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798. eaqliu@ntu.edu.sg ewser@ntu.edu.sg.
authors.forename: L K
authors.initials: LK
authors.lastname: Chin
authors.affiliation: School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798. eaqliu@ntu.edu.sg ewser@ntu.edu.sg.
authors.forename: H F
authors.initials: HF
authors.lastname: Chen
authors.affiliation: School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798. eaqliu@ntu.edu.sg ewser@ntu.edu.sg.
authors.forename: W M
authors.initials: WM
authors.lastname: Zhu
authors.affiliation: School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798. eaqliu@ntu.edu.sg ewser@ntu.edu.sg.
authors.forename: J B
authors.initials: JB
authors.lastname: Zhang
authors.affiliation: Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232.
authors.forename: P H
authors.initials: PH
authors.lastname: Yap
authors.affiliation: Interdisciplinary Graduate School, Nanyang Technological University, Singapore 639798.
authors.forename: B
authors.initials: B
authors.lastname: Liedberg
authors.affiliation: Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan and College of Medical Science and Technology, Taipei Medical University, Taipei 110, Taiwan.
authors.forename: K
authors.initials: K
authors.lastname: Wang
authors.affiliation: School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798. eaqliu@ntu.edu.sg ewser@ntu.edu.sg.
authors.forename: G
authors.initials: G
authors.lastname: Wang
authors.affiliation: School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798. eaqliu@ntu.edu.sg ewser@ntu.edu.sg.
authors.forename: W
authors.initials: W
authors.lastname: Ser
authors.affiliation: School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798. eaqliu@ntu.edu.sg ewser@ntu.edu.sg.
authors.forename: A Q
authors.initials: AQ
authors.lastname: Liu