共查询到20条相似文献,搜索用时 31 毫秒
1.
In this paper, a scanning laser induced fluorescence detection system for capillary electrophoresis microchip based on single-mode optical fiber has been established using a green diode pumped solid-state laser as excitation source. It includes laser induced fluorescence detection subsystem, capillary electrophoresis microchip, mechanical scanning platform, channel identification unit and fluorescent signal processing subsystem. Two V-shaped detecting probes composed of optical fiber for transmitting the excitation light and detecting the induced fluorescence were constructed. Parallel four-channel signal analysis of capillary electrophoresis was performed by this system using Rhodamine B sample solution. Furthermore, the separation and distinction of different concentrations of Rhodamine B sample were achieved with the constructed detection system. The lowest detected concentration is 1.0 × 10−5 mol/L for Rhodamine B sample. The results show that the constructed detection system possesses some advantages of compact structure, low cost, and better stability which could be used as reference to the design and optimization of laser induced fluorescence detection system for capillary electrophoresis microchip. 相似文献
2.
Femtosecond laser-written integrated devices involving Fresnel Zone Plates (FZPs) and waveguide arrays are demonstrated as built-in optical couplers. These structures were fabricated in borosilicate glass using a direct laser writing technique. The optical properties of these integrated photonic structures were investigated using CW lasers and high-resolution CCDs. For a single FZP coupled to a single waveguide, the overall coupling efficiency was 9%. A multiplexed optical coupler composed of three FZP layers was demonstrated to couple three waveguides simultaneously in a waveguide array. Structures of this type can be used as platforms for multichannel waveguide coupling elements or as microfluidic sensors that require higher light collecting efficiency. 相似文献
3.
Low-cost, compact, automated optical microsystems for chemical analysis, such as microflow cytometers for identification of individual biological cells, require monolithically integrated microlenses for focusing in microfluidic channels, to enable high-resolution scattering and fluorescence measurements. The multimode interference device (MMI), which makes use of self-imaging in multimode waveguides, is shown to be a simple and effective alternative to the microlens for microflow cytometry. The MMIs have been designed, realized, and integrated with microfluidic channels in a silica-based glass waveguide material system. Focal spot sizes of 2.4 μm for MMIs have been measured at foci as far as 43.7 μm into the microfluidic channel. 相似文献
4.
A compact LED-based module for DNA capillary electrophoresis 总被引:1,自引:0,他引:1
A setup consisting of a bifurcated optical fiber made from high-transmission fused-silica cores with relatively high numerical apertures (NA=0.22), high-power cyan light-emitting diodes (LEDs) and Peltier cooling elements controlled by a proportional–integrative–derivative (PID) module is introduced to replace bulky, power- consuming lasers conventionally used in laser induced fluorescence (LIF) microchip capillary electrophoresis (μCE). The output fiber beam size, divergence, power distribution and power stability over time are documented. A modified epifluorescence microscope arrangement is used in conjunction with a compact fixed spectrometer aligned with a cooled charge-coupled device (CCD) camera for added sensitivity. Fluorescent dyes such as fluorescein, 6-carboxyfluorescein (6-FAM) and rhodamine B can be detected in cyclic olefin copolymer (COC) and glass microchannels at submicromolar levels. A single-stranded DNA oligonucleotide (10-mer) labeled with 6-FAM is also detected with reasonable signal-to-noise ratio when electrophoretically migrated at 100 V/cm. The compact LED excitation system presented herein will allow using capillary electrophoresis for DNA detection in compact mobile devices. 相似文献
5.
We present a fully planar integrated optical approach to single-molecule detection based on microfabricated planar networks of intersecting solid and liquid-core waveguides. We study fluorescence from dye molecules in liquid-core antiresonant reflecting optical waveguides, and demonstrate subpicoliter excitation volumes, parallel excitation through multiple pump waveguides, and single-molecule detection sensitivity. Integrated silicon photonics combined with single-molecule detection in solution create a compact, robust, and sensitive platform that has applications in numerous fields ranging from atomic physics to the life sciences. 相似文献
6.
Focused proton beam writing has been utilized to fabricate optical channel waveguides in Nd:GGG crystals. The 1?MeV proton beam irradiation creates a local modified region with positive refractive index changes at the end of the proton trajectory, in which the channel waveguide could confine the light field in a symmetric way. Room-temperature laser emission has been achieved at 1063.7?nm, with absorbed pump power of 61?mW (at 808?nm). The obtained slope efficiency of the Nd:GGG waveguide laser system is as high as 66%, which is, to our best knowledge, the highest value for integrated lasers from ion beam processed channel waveguide systems. 相似文献
7.
Hô N Phillips MC Qiao H Allen PJ Krishnaswami K Riley BJ Myers TL Anheier NC 《Optics letters》2006,31(12):1860-1862
We demonstrate the design, fabrication, and characterization of single-mode low-loss waveguides for mid-infrared (MIR) wavelengths. Planar waveguide structures were fabricated from multilayer thin films of arsenic-based chalcogenide glasses followed by the creation of channel waveguides by using the photodarkening effect. Propagation losses as low as 0.5 dB/cm were measured for a quantum cascade laser end-fire coupled into the waveguides. This is a first step toward the design and fabrication of integrated optical components for MIR applications. 相似文献
8.
Zhongke Wang Koji Sugioka Katsumi Midorikawa 《Applied Physics A: Materials Science & Processing》2008,93(1):225-229
By the one-continuous fabrication procedure of hollow microstructures using femtosecond (fs) laser direct writing followed
by thermal treatment, successive chemical wet etching and additional annealing, three-dimensional integration of microoptics
with microfluidics, i.e., a planoconvex microlens with a microfluidic chamber, in a single Foturan glass chip was achieved.
Further integration of an optical waveguide was performed through internal refractive index modification by fs laser direct
writing after the fabrication of the microlens and the microchamber. An “all-in-one” microchip that is highly effective for
on-chip photonic biosensing can be manufactured by the present technique with easy assembly of each microcomponent and without
any cumbersome processes for stacking and joining substrates. Experimental demonstration of photonic biosensing using the
integrated microchip has revealed that fluorescence analysis and absorption measurement of liquid samples can be performed
with efficiencies enhanced by factors of 8 and 3, respectively. 相似文献
9.
A. A. Egorov 《Optics and Spectroscopy》2012,112(2):280-290
Specifics of theoretical analysis of wave phenomena in irregular integrated optical waveguides are investigated. The object
of the investigation and the main types of irregularities (smooth, statistical, and sharp) are described. The goals of the
numerical modeling are formulated. The structure of the program and the general structure of the algorithm allowing numerical
investigation of guided modes’ scattering from 3D-irregularities of an integrated optical waveguide are described. The dispersion
relations of the TE and TM modes of the integrated optical waveguide under investigation, as well as field patterns of the
radiating TE modes of the substrate and the laser radiation scattered from the three-dimensional guiding-layer inhomogeneities
of an integrated optical waveguide, are presented. The results are analyzed in detail. The methods developed can be used for
numerical investigation of the characteristics of laser radiation scattered in various optical waveguides with three-dimensional
irregularities. 相似文献
10.
Optical waveguide arrays induced in fused silica by void-like defects using femtosecond laser pulses
C. Méndez J.R. Vázquez de Aldana G.A. Torchia L. Roso 《Applied physics. B, Lasers and optics》2007,86(2):343-346
We report a new approach to the microfabrication of permanent optical waveguide arrays inside fused silica induced by focusing
infrared femtosecond laser pulses with microjoule energy. These arrays consist of waveguides limited by void-like damage zones
with very loose coupling among adjacent guides, thus allowing the excitation of a single one. The proposed method shows the
possibility of using created void-like structures for both the fabrication of integrated optical devices as well as for the
control of previously induced refractive index change regions.
PACS 42.65.Re; 42.82.Et; 42.79.-e 相似文献
11.
Mogensen KB Friis P Hübner J Petersen N Jørgensen AM Telleman P Kutter JP 《Optics letters》2001,26(10):716-718
The UV wavelength region is of great interest in absorption spectroscopy, which is employed for chemical analysis, since many organic compounds absorb in only this region. Germanium-doped silica, which is often preferred as the waveguide core material in optical devices for telecommunication, cannot accommodate guidance below 400 nm, owing to the presence of UV-absorbing centers. We show that silicon oxynitride (SiO(x) N(y)) waveguides exhibit very good UV performance. The propagation loss for 24-microm -wide SiO(x)N (y) waveguides was found to be ~1.0dB/cm in the wavelength range 220-550 nm. The applicability of these waveguides was demonstrated in a biochemical microsystem consisting of multimode buried-channel SiO(x)N (y) waveguides that were monolithically integrated with microfluidic channels. Absorption measurements of a beta -blocking agent, propranolol, at 212-215 nm were performed. The detection limit was reached at a concentration of 13microM , with an optical path length of 500microm (signal/noise ratio, 2). 相似文献
12.
In this Letter, we demonstrate a biocompatible microscale optical device fabricated from agarose hydrogel that allows for encapsulation of cells inside an optical waveguide. This allows for better interaction between the light in the waveguide and biology, since it can interact with the direct optical mode rather than the evanescent field. We characterize the optical properties of the waveguide and further incorporate a microfluidic channel over the optical structure, thus developing an integrated optofluidic system fabricated entirely from agarose gel. 相似文献
13.
14.
I. U. Primak 《Technical Physics》2004,49(10):1319-1324
The sensitivity of integrated optical sensors based on prismatic excitation of planar waveguides is analyzed. It is shown
that the sensitivity peak is attained when the waveguide modes are excited under nearly critical conditions. 相似文献
15.
Fabrication of microfluidic optical waveguides on glass chips with femtosecond laser pulses 总被引:1,自引:0,他引:1
We describe the fabrication of microfluidic channel structures on the surface of a borosilicate glass slide by femtosecond laser direct writing for optical waveguide application. Liquid with a variable refractive index is fed into the microchannel, serving as the core of the waveguide. We demonstrate that either a multimode or a single-mode waveguide can be achieved by controlling the refractive index of the liquid. 相似文献
16.
离子交换铒掺杂硅酸盐玻璃波导光放大特性 总被引:5,自引:1,他引:4
将集成光学放大器用于光纤通信系统中是人们越来越感兴趣的课题,由此导致人们寻找与此相适应的稀土掺杂玻璃材料。给出了一系列Er^3 /Yb^3 共掺杂硅酸盐玻璃波导的制备和光谱特性的基本结果。平面和条型波导均由Ag^ -Na^ 离子交换技术制备。光谱测量显示,所有样品在1532nm都观测到了荧光发射峰.其半高谱宽为19nm。用波长为514.5nm和980nm的激光抽运,测得多数样品中Er^3 离子在亚稳态^4I13.2能级上的荧光寿命均为7ms左右。Er^3 /Yb^3 共掺杂玻璃的上转换均低于单掺Er^3 玻璃。用250mW,波长为980nm的激光抽运3.5cm长的条形波导,在1536nm波段下得到的最大净增益是5dB,增益谱的半峰全宽是14nm。 相似文献
17.
18.
It is known that deep ultraviolet (UV) radiation induces a refractive index increase in the surface layer of polymethylmethacrylate (PMMA) samples. This effect can be used for the fabrication of integrated optical waveguides. PMMA is of considerable interest for bio and chemical sensing applications because it is biocompatible and can be micromachined by several methods, e.g. structuring by photolithography, ablation and hot embossing. In the presented work direct UV irradiation of a common PMMA substrate by a krypton fluoride excimer laser beam through a contact mask has been used to write integrated optical Mach-Zehnder interferometers (MZI). MZI are used as sensitive bio and chemical sensors. The aim was to determine contact mask design and laser irradiation parameters for fabricating single-mode MZI for the infrared region from 1.30 μm to 1.62 μm. Straight and curved waveguides have been generated and characterized to determine the optical losses. The generation of channel waveguide structures has been optimized by a two step irradiation process to minimize the lithographic writing time and optical loss. By flood exposure to UV laser radiation in the first step the optical absorption of PMMA can be increased in the irradiated region. The required refractive index profile is then achieved with a second lithographic irradiation. The spectral behaviour of an unbalanced, integrated optical MZI fabricated by this excimer laser based contact mask method is shown for the first time. Further the optical intensity at the output port of a MZI has been measured while the optical path length difference was tuned by creating a temperature difference between the two arms of the MZI. 相似文献
19.
Trivalent samarium ion (Sm3+) doped SU8 polymer materials were synthesized and characterized. Intense red emission at 645 nm was observed under UV laser light excitation. Spectroscopic investigations show that the doped materials are suitable for realizing planar optical waveguide amplifiers. About 100 μm wide multimode Sm3+-doped SU8 channel waveguides were fabricated using a simple UV exposure process. At 250 mW, 351 nm UV pump power, a signal enhancement of ∼7.4 dB at 645 nm was obtained for a 15 mm long channel waveguide. 相似文献
20.
将多光子激发荧光探测与毛细管电泳技术相结合,研制了多光子激发荧光-毛细管电泳联用装置。这种方法可以高效快速的分离检测复杂样品中多种不同的荧光分子。作者对5HT,FAD,NADH这三种重要的生物分子,不用染料标记,分别用双光子激发和三光子激发,进行了直接的分离、识别和检测。得到的检测限分别是5HT 1.0×10-6 mol·L-1,FAD 7.4×10-7 mol·L-1,NADH 9.8×10-7 mol· L-1。5HT的检测限比紫外吸收低2个数量级;FAD和NADH的检测限比紫外吸收低1个数量级。 相似文献