共查询到20条相似文献,搜索用时 15 毫秒
1.
The impact of particle defects in the free propagation region on the performance of an etched diffraction grating demultiplexer is analyzed in the present paper. Numerical simulations using a method of moment and a Green function method show that particle defects with some special sizes can result in a strong resonance with the incident wavelength and will produce a large scattering loss. 相似文献
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In this paper, we propose a novel reconfigurable optical dispersion compensator achieved by waveguide grating and electro-optic effect of lithium niobate on insulator. Reconfigurable compensation is attained by controlling the voltage of the electrodes on waveguide grating. The measured bit error rate in the system is below 10?10 in a 40 Gbit/s quadrature phase shift keying transmission system. 相似文献
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We propose a new type of arrayed waveguide grating (AWG) device that operates as a Fourier-transform (FT) spectrometer without the need of scanning elements. The large input aperture size typical of a FT spectrometer eliminates the requirement for a narrow single-mode input waveguide while still achieving high spectral resolution with a markedly increased light-gathering capability (etendue). An example of the device with a resolution of 0.07 nm (approximately 10 GHz) and designed for a silicon-on-insulator platform is presented. The calculated spectra show no noticeable deterioration for aperture widths as large as 40 microm, yielding more than a 50-fold increase in aperture size compared with conventional AWG or echelle grating based devices at the equivalent resolution. 相似文献
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A novel 1 × N optical switch array based on arrayed waveguide grating (AWG) structure is presented in this paper. The device is designed for polymeric materials with a large negative thermooptic (TO) coefficient, which is employed to change the imaging effect and to realize optical switching. When input wavelength is located in a special waveband, the optical signal will image at different output channel as temperature changes. The two-dimensional finite difference beam propagation method (FD-BPM) has been used to simulate a 1 × 9 optical switch array. The insertion loss of this switch array is below 1.37 dB and the extinction ratio is better than 31 dB at 1550 nm, when the coupling and propagation loss is neglected. The optimum design and the simulation results show that this structure could be a multiple wavelengths switching at the same time. 相似文献
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Dolgaleva K Malacarne A Tannouri P Fernandes LA Grenier JR Aitchison JS Azaña J Morandotti R Herman PR Marques PV 《Optics letters》2011,36(22):4416-4418
We experimentally demonstrate the first integrated temporal Fourier transformer based on a linearly chirped Bragg grating waveguide written in silica glass with a femtosecond laser. The operation is based on mapping the energy spectrum of the input optical signal to the output temporal waveform by making use of first-order chromatic dispersion. The device operates in reflection, has a bandwidth of 10 nm, and can be used for incident temporal waveforms as long as 20 ps. Experimental results, obtained through both temporal oscilloscope traces and Fourier transform spectral interferometry, display a successful Fourier transformation of in-phase and out-of-phase pairs of input optical pulses, and demonstrate the correct functionality of the device for both amplitude and phase of the temporal output. 相似文献
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The polarization dependence of an arrayed waveguide grating demultiplexer based on Si photonic wires is analyzed. The height and width of the arrayed waveguides are optimized to make the channel spacing polarization insensitive. To make the central wavelength polarization insensitive, different diffraction orders are chosen for TE and TM polarizations, and the remaining polarization-dependent wavelength is compensated with a noncentral input. A detailed design procedure is presented and numerical simulation results are given. 相似文献
9.
In this Letter, we present an electrically tunable holographic waveguide display(HWD) based on two slanted holographic polymer dispersed liquid crystal(HPDLC) gratings. Experimental results show that a see-through effect is obtained in the HWD that both the display light from HWD and the ambient light can be clearly seen simultaneously. By applying an external electric field, the output intensity of the display light can be modulated,which is attributed to the field-induced rotation of the liquid crystal molecules in the two HPDLC gratings.We also show that this electrically tunable performance enables the HWD to adapt to different ambient light conditions. This study provides some ideas towards the development of HWD and its application in augmented reality. 相似文献
10.
We propose a novel method that, for the first time to our knowledge, makes it possible to tailor the spectral response of an input grating coupler. This method is based on the idea of computer-generated waveguide holography. Grating couplers with different spectral responses have been designed and fabricated, and experimental results are presented that demonstrate the effectiveness of the proposed method. 相似文献
11.
We propose and demonstrate a compact tunable optical dispersion compensation (TODC) device with a 100 GHz free spectral range capable of mitigating chromatic dispersion impairments. The TODC is based on longitudinal movement of a waveguide grating router, resulting in chromatic dispersion compensation of ±1000 ps/nm. We employed our TODC device for compensating 42.8 Gbit/sec differential phase-shifting keying signal, transmitted over 50 km fiber with a -2 dB power penalty at 10??. 相似文献
12.
Analytical and numerical study on grating depth effects in grating coupled waveguide sensors 总被引:1,自引:0,他引:1
R. Horvath L. C. Wilcox H. C. Pedersen N. Skivesen J. S. Hesthaven P. M. Johansen 《Applied physics. B, Lasers and optics》2005,81(1):65-73
The in-coupling process for grating-coupled planar optical waveguide sensors is investigated in the case of TE waves. A simple analytical model based on the Rayleigh–Fourier–Kiselev method is applied to take into account the depth of the grating coupler, which is usually neglected in the modeling. Analytical expressions are derived both for the position and width of the in-coupling peaks to illustrate the effects of grating depth on the guided mode resonances in grating coupled waveguide sensors. Numerical computations verify the model for shallow gratings both in terms of peak shape and position and provide the limitations for the analytical formulas. 相似文献
13.
We consider the initial stage of formation of photorefractive gratings in planar waveguides based on cubic electrooptic crystals.
We have obtained solutions for the components of the space-charge field for arbitrary ratios between parameters characterizing
the spatial inhomogeneity of the light interference pattern in the waveguide as well as the diffusion length. The dependence
of the component of the space-charge field parallel to the grating vector on its period in the initial section of the recording
is also determined by the sum and difference of the transverse propagation constants of the interacting waveguide modes. We
show that for waveguide interactions characterized by a small transverse scale of spatial inhomogeneity, the distributions
of the space-charge field and the light intensity in the interference pattern are substantially different. These effects must
be considered in analysis of the nonlinear interactions occurring in a refractive index grating due to the electrooptical
effect.
Tomsk University of Control Systems and Radioelectronics. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika,
pp. 65–73, June, 1997. 相似文献
14.
Interrogating fiber Bragg grating sensors by thermally scanning a demultiplexer based on arrayed waveguide gratings 总被引:2,自引:0,他引:2
We evaluate a wavelength interrogation technique based on an arrayed waveguide grating (AWG). Initial results show that the Bragg wavelength of fiber Bragg grating (FBG) sensors can be precisely interrogated by thermally scanning an AWG-based demultiplexer. The technique potentially offers a low-cost, compact, and high-performance solution for the interrogation of FBG distributed sensors and multisensor arrays. 相似文献
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导模共振生物传感器由于具有微型化、免标签、高通量和实时检测等优势被广泛研究。利用严格耦合波理论分析了该生物传感器对样品折射率和厚度的灵敏度随共振波长的变化规律。当样品厚度和共振波长一定时,其折射率灵敏度恒定;随着共振波长的增大,折射率灵敏度显著提高。当样品折射率和共振波长一定时,厚度灵敏度随着厚度的增加而降低,最后趋近于0;当共振波长增加时,厚度灵敏度明显提高,厚度测量范围增大。结果表明:选取较长的共振波长有利于样品的检测和分析。 相似文献
17.
Fei Wang Chunsheng Ma Wei Sun Aize Li Yu Zhao Zhenhua Jiang Daming Zhang 《Optics & Laser Technology》2005,37(7):527-531
In this paper, certain important parameters are optimized for a polymer/Si arrayed waveguide grating (AWG) multiplexer by using grating theory. A 32-channel multiplexer is designed and fabricated using newly synthesized fluorinated poly (ether ether ketone) with a high thermal stability. The measured wavelength channel spacing is 0.796 nm, and center wavelength and 3-dB bandwidth are 1548 nm and 0.3 nm, respectively. 相似文献
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Rajneesh Kaler 《Optik》2011,122(7):620-625
In this paper, we have demonstrated the quality-of-service offered by the metropolitan area network which is based on optical cross connect (OXC) and arrayed waveguide grating (AWG) demultiplexer operating at 10 Gb/s with 0.1 nm channel spacing for NRZ signal transmission. The data is successfully transmitted to a distance of 40 km with a reasonably good BER of 2.388 × 10−35. The OXC and AWG demultiplexers in the proposed architecture allow incremental expansion in terms of the number of wavelength channels to be transmitted. Dispersion and crosstalk are the main signal-degrading factors arising from the operation of the OXC and the effectiveness of each factor is individually investigated. 相似文献
20.
In this paper, a photonic crystal waveguide platform on silicon-on-insulator substrate is proposed in order to realize a highly sensitive refractive index based biosensor. Following the design, the analysis of the sensor structure are made by using the three dimensional Finite Difference Time Domain method. The principle of sensing is based on the change in refractive index, which in turn changes the output spectrum of the waveguide. Results show that the sensitivity of the sensor depends mainly on the geometrical properties of the defect region of the photonic crystal structure. The phenomenon is verified for various samples having refractive index ranging from 1 (air) to 1.57 (Bovine serum albumin). Further, the structure is compared with few other conventional photonic crystal waveguide designs to analyze the sensing performance. The estimated value of sensitivity of the sensor is found to be 260 nm/RIU with a detection limit of 0.001 RIU. This high sensitivity can enhance the performance of low-concentration analytes detection. 相似文献