Sugioka K.,RIKEN |
Cheng Y.,CAS Shanghai Institute of Optics and fine Mechanics
Lab on a Chip - Miniaturisation for Chemistry and Biology | Year: 2012
Femtosecond laser direct writing is a promising technique for fabricating optofluidic devices since it can modify the interior of glass in a spatially selective manner through multiphoton absorption. The chemical properties of laser-irradiated regions in glass are modified allowing them to be selectively etched by subsequent wet etching using aqueous solutions of etchants such as hydrofluoric (HF) acid. This technique can be used to directly form three-dimensional microfluidic systems. The two-step process can also be used to fabricate free-space optical components such as micromirrors and microlenses inside glass. In addition, femtosecond laser direct writing can alter the optical properties of a substrate to create a wide range of micro-optical components inside glass, including optical waveguides, Mach-Zehnder interferometers, and optical attenuators. The unique ability of femtosecond laser direct writing to simultaneously alter the chemical and optical properties of glass opens up a new avenue for fabricating a variety of optofluidic microchips for biological analysis. Optofluidic microchips fabricated using femtosecond lasers have been used to determine the functions of living microorganisms, determine the concentrations of liquid samples, detect and manipulate single cells, and rapidly screen algae populations. This paper presents a comprehensive review of optofluidic devices for biological analysis fabricated by femtosecond laser processing. © 2012 The Royal Society of Chemistry. Source
Xu J.,CAS Shanghai Institute of Optics and fine Mechanics
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2011
We theoretically demonstrate the generation of a high-order harmonic and isolated attosecond pulse in an orthogonally polarized laser field, which is synthesized by an 800-nm chirped laser pulse and an 800-nm chirp-free laser pulse. Owing to the instantaneous frequency increasingly reducing close to the center of the driving pulse, the extreme ultraviolet supercontinuum for the chirped synthesized field is even broader than that for an orthogonal chirp-free two-color laser field. It is found that the broadband supercontinuum spectrum can be achieved for the driving pulse with ten and above optical cycles. After phase compensation an isolated attosecond pulse with a duration of ∼16 as is produced. Furthermore, the optimization of the chirping rate parameters is investigated to achieve cutoff extension and an isolated short attosecond pulse. © 2011 American Physical Society. Source
Liu L.,CAS Shanghai Institute of Optics and fine Mechanics
Applied Optics | Year: 2013
This paper reviews our studies on coherent and incoherent synthetic-aperture imaging ladars (SAILs). Using optical diffraction, a systematic theory of side-looking SAIL was mathematically formulated and the necessary conditions for assuring a correct phase history are established. Based on optical transformation and regulation of wavefront, a down-looking SAIL of two distinctive architectures was invented and the basic principle, systematic theory, design equations, and necessary conditions are presented. An incoherent spotlight-mode SAIL was proposed, and detailed mathematically. To validate the concepts, laboratory experiments were conducted. The spatially and temporally dependent laser speckles are analyzed by applying the partial coherence theorem, and proposals to reduce their effect are given. Optical antennas and their components are discussed. It is shown that for down-looking SAIL the width of the scanning strip may be greatly increased without loss of high resolution, and the influences from atmospheric turbulence and unmodeled line-of-sight motion can be automatically compensated. © 2013 Optical Society of America. Source
CAS Shanghai Institute of Optics and fine Mechanics | Date: 2011-06-28
A compact optical mount for adjust optical component in 3 dimensions. Based on the traditional 2D adjustable optical mount, its inner space is utilized for installing the third dimension angular adjustment. By virtue of its compact structure, convenient adjustment, high precision and good stability, the invention is suitable for adjusting small optics in 3 dimensions, by which the real optical axel can agree with the idea optical axel well to fast adjust the whole optical system.
Shanghai Micro Electronics Equipment Co., CAS Shanghai Institute of Optics and fine Mechanics | Date: 2014-01-10
Four-axis four-subdividing interferometer comprising a four-axis light splitting module and an interference module which are sequentially arranged along the incident direction of polarization orthogonal double-frequency laser. The four-axis light splitting system comprises three 50% plane beam splitters and three 45-degree plane reflecting mirrors. The invention comprises a four-axis four-subdividing plane mirror interferometer and a four-axis four-subdividing differential interferometer. In the differential interferometer, an adjustable 45-degree reflecting minor is used to guide the reference light to a reference reflecting minor which is arranged in the same direction as a measurement minor and fixed on the moving object.