Optics Express (OPT EXPRESS )

Publisher: Optical Society of America, Optical Society of America

Description

Optics Express is the world's first international all-electronic journal of optics. Published bi-weekly, Optics Express offers OSA quality, rapid publication of original, peer-reviewed articles in all fields of optical science and technology. Color graphics and audio or video features are included at no extra cost to the authors. This journal is freely and widely available to readers via the Internet.

Impact factor 3.53

  • Hide impact factor history
     
    Impact factor
  • 5-year impact
    3.58
  • Cited half-life
    3.80
  • Immediacy index
    0.80
  • Eigenfactor
    0.25
  • Article influence
    1.13
  • Website
    Optics Express website
  • Other titles
    Optics express
  • ISSN
    1094-4087
  • OCLC
    37160672
  • Material type
    Document, Periodical, Internet resource
  • Document type
    Internet Resource, Computer File, Journal / Magazine / Newspaper

Publisher details

Optical Society of America

  • Pre-print
    • Author can archive a pre-print version
  • Post-print
    • Author can archive a post-print version
  • Conditions
    • On non-profit server
    • On author's personal website or arXiv only
    • Publisher's version/PDF may be used
    • Publisher copyright and source must be acknowledged with set statement (see policy)
    • Set statement to accompany deposit (see policy)
    • Not allowed on PubMed Central, unless funded by NIH
  • Classification
    ​ green

Publications in this journal

  • [Show abstract] [Hide abstract]
    ABSTRACT: Highly reflective coatings with strong light scattering effect have many applications in optical components and optoelectronic devices. This work reports titanium dioxide (TiO2) pigment-based reflectors that have 2.5 times higher broadband diffuse reflection than commercially produced aluminum or silver based reflectors and result in efficiency enhancements of a single-junction amorphous Si solar cell. Electrophoretic deposition is used to produce pigment-based back reflectors with high pigment density, controllable film thickness and site-specific deposition. Electrical conductivity of the pigment-based back reflectors is improved by creating electrical vias throughout the pigment-based back reflector by making holes using an electrical discharge / dielectric breakdown approach followed by a second electrophoretic deposition of conductive nanoparticles into the holes. While previous studies have demonstrated the use of pigment-based back reflectors, for example white paint, on glass superstrate configured thin film Si solar cells, this work presents a scheme for producing pigment-based reflectors on complex shape and flexible substrates. Mechanical durability and scalability are demonstrated on a continuous electrophoretic deposition roll-to-roll system which has flexible metal substrate capability of 4 inch wide and 300 feet long.
    Optics Express 02/2015; 23(3).
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this work, InGaN/GaN light-emitting diodes (LEDs) possessing varied quantum well (QW) numbers were systematically investigated both numerically and experimentally. The numerical computations show that with the increased QW number, a reduced electron leakage can be achieved and hence the efficiency droop can be reduced when a constant Shockley-Read-Hall (SRH) nonradiative recombination lifetime is used for all the samples. However, the experimental results indicate that, though the efficiency droop is suppressed, the LED optical power is first improved and then degraded with the increasing QW number. The analysis of the measured external quantum efficiency (EQE) with the increasing current revealed that an increasingly dominant SRH nonradiative recombination is induced with more epitaxial QWs, which can be related to the defect generation due to the strain relaxation, especially when the effective thickness exceeds the critical thickness. These observations were further supported by the carrier lifetime measurement using a pico-second time-resolved photoluminescence (TRPL) system, which allowed for a revised numerical modeling with the different SRH lifetimes considered. This work provides useful guidelines on choosing the critical QW number when designing LED structures.
    Optics Express 02/2015; 23(3).
  • [Show abstract] [Hide abstract]
    ABSTRACT: The transmittance of phosphor-in-glass (PIG) color converter material was studied as a factor affecting the luminescence properties of light emitting diode packaging; it is closely related to the residual pores of sintered glass. In this study, the correlation between porosity and optical properties of the glass and PIG plates was investigated. The transmittance, luminescence properties, and porosity were measured by UV-visible spectrometer, integrating sphere and scanning electron microscope, respectively. Transmittance of the sintered glass plate and the luminous efficacy of the PIG plate both increase with decreased porosity, while the light scattering coefficient decreases. Luminescence properties such as emission intensity and color coordinates are also influenced by transmittance of the PIG plate.
    Optics Express 02/2015; 23(3).
  • [Show abstract] [Hide abstract]
    ABSTRACT: An anti-glare luminaire design is proposed to reduce the effect of glare and the multi-shadow while preserving high optical efficiency, high illumination uniformity and low unified glare rating (UGR). Comparison to the traditional direct light emitting diode (LED) luminaire in optical simulations showed an enhancement of the illumination uniformity from 64.9% to 80.0%. The optical efficiency was 79.5%, and the UGR value was controlled under 18.8. For the actual measurement, the finished product had an illumination uniformity of 77.0%, optical efficiency of 76.0%, UGR value of 19.0, and efficacy of 81.4 lm/w. Through this design, the lighting performance was greatly enhanced.
    Optics Express 02/2015; 23(3).
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    ABSTRACT: This paper proposes an energy-saving passive optical network framework (ESPON) that aims to incorporate optical network unit (ONU) sleep/doze mode into dynamic bandwidth allocation (DBA) algorithms to reduce ONU energy consumption. In the ESPON, the optical line terminal (OLT) schedules both downstream (DS) and upstream (US) transmissions in the same slot in an online and dynamic fashion whereas the ONU enters sleep mode outside the slot. The ONU sleep time is maximized based on both DS and US traffic. Moreover, during the slot, the ONU might enter doze mode when only its transmitter is idle to further improve energy efficiency. The scheduling order of data transmission, control message exchange, sleep period, and doze period defines an energy-efficient scheme under the ESPON. Three schemes are designed and evaluated in an extensive FPGA-based evaluation. Results show that whilst all the schemes significantly save ONU energy for different evaluation scenarios, the scheduling order has great impact on their performance. In addition, the ESPON allows for a scheduling order that saves ONU energy independently of the network reach.
    Optics Express 02/2015; 23(3).
  • [Show abstract] [Hide abstract]
    ABSTRACT: Metal transparent conductive electrode (TCE) with surface plasmons has been extensively studied for light absorption enhancement in solar cells and light extraction in Light-Emitting Diodes etc. But its transparent conductive properties and surface plasmons are controlled by its micromorphologies and microstructures. In this work, photoelectric coupling effects and optical transmittance modulations of period, linewidth and height of Au nanowire in square mesh electrode were investigated detailedly using a comprehensive finite-difference time domain calculation stimulation, and then Au square mesh TCEs with the 500 nm in period, 70 nm in height and linewidth ranging from 60 to 100 nm were fabricated using electron beam lithography. The measured results showed that the optical transmittance of the TCEs is about 70% in the 350-700 nm wavelength range and over 80% in the 700-1000 nm range, which accord with the theoretical simulation results. Optical transmittance is affected by reflection loss, localized surface plasmon resonances and surface plasmon polarizations (SPPs) absorption loss, concerned about geometry parameters. SPPs dip peak position exhibits a blue-shift from 844 to 812 nm and the width of peak increases with increasing the linewidth from 60 to 100 nm, The measured surface resistivity of the TCEs with the 500 nm in period, 50 nm in height and 50 nm in linewidth is about 74.5 Ω/m2, about two times bigger than that of commercial indium tin oxide glass.
    Optics Express 02/2015; 23(3).
  • [Show abstract] [Hide abstract]
    ABSTRACT: In present study, the intense sensitized three photon near-infrared quantum cutting luminescence of Tm3+ ion activator in Tm3+Bi3+:YNbO4 powder phosphor is reported. It is induced both by [{1G4→3H4, 3H6→3H5} or {1G4→3H5, 3H6→3H4}] and {3H4→3F4, 3H6→3F4} cross-energy transfer. We found that the 1820.0 nm 3F4→3H6 luminescence intensity of Tm0.08Bi0.01Y0.91NbO4 powder phosphor excited by 302.0 nm is 151 and 8.38 times larger, compared to Tm0.005Y0.995NbO4 excited by 302.0 and 468.0 nm, in which the quantum cutting takes place between Tm3+ ions and Bi3+ ion only acts as sensitizer. To the knowledge of the authors, it is the first time that the effective Bi3+ sensitized near-infrared quantum cutting of Tm3+ ion activator has been reported. It can facilitate the probing of the next-generation environmentally friendly germanium solar cell.
    Optics Express 02/2015; 23(3).
  • [Show abstract] [Hide abstract]
    ABSTRACT: This study demonstrates the application of DBR structure into the remote phosphor structure to improve the angular correlated color temperature (CCT) deviation in white light-emitting diodes (WLEDs). In the experiment, the LED device with DBR structure yielded a higher luminous efficiency than a conventional structure. The CCT deviation can be improved from 1758K to 280K in a range of −70 to 70 degree and the luminous flux increases more than 10% due to the enhancement of the light extraction of the blue light. Moreover, the reflectance of the different DBR structures is analyzed with different angles to reveal the reasons of such improvements. As the result, this LED device with DBR structure shows the great potential to use as the next generation lighting source.
    Optics Express 02/2015; 23(3).
  • [Show abstract] [Hide abstract]
    ABSTRACT: We present a non-z-scanning multi-molecule tracking system with nano-resolution in all three dimensions and extended depth of field (DOF), which based on distorted grating (DG) and double-helix point spread function (DH-PSF) combination microscopy (DDCM). The critical component in DDCM is a custom designed composite phase mask (PM) combining the functions of DG and DH-PSF. The localization precision and the effective DOF of the home-built DDCM system based on the designed PM were tested. Our experimental results show that the three-dimensional (3D) localization precision for the three diffraction orders of the grating are σ-1st(x, y, z) = (6.5 nm, 9.2nm, 23.4 nm), σ0th(x, y, z) = (3.7 nm, 2.8nm, 10.3 nm), and σ+1st(x, y, z) = (5.8 nm, 6.9 nm, 18.4 nm), respectively. Furthermore, the total effective DOF of the DDCM system is extended to 14 μm. Tracking experiment demonstrated that beads separated over 12 μm along the axial direction at some instants can be localized and tracked successfully.
    Optics Express 01/2015; 23(2).
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    ABSTRACT: A thin film based erbium doped tellurium oxide (TeO2) waveguide amplifier producing gain from 1500nm to 1640nm when pumped at 980nm is demonstrated. At measured internal gains exceeding 14dB lasing due to end facet reflection set in producing the first tellurite waveguide laser. High gains were observed despite significant upconversion, whose impact appears to be mitigated to some extent by residual OH contamination. The device displayed no photosensitive effects from either the high pumping intensities used or the intracavity intensity at 1550nm.
    Optics Express 01/2015; 23(2).
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    ABSTRACT: We demonstrate experimentally and numerically that an x-ray prism made of beryllium can be used to disperse and monochromatize x-rays. A polished beryllium cuboid was employed as refractive and dispersive optics. The results of a proof-of-principle experiment and methods of performance optimization are presented. The spatial separation of undulator harmonics and their subsequent selection using a slit are described. A numerical study, assuming realistic beam and beamline parameters, suggests that undulator harmonics can be spatially separated in the range from 3 keV to beyond 20 keV, while maintaining throughput above 50%. Refractive optics is particularly suitable for low-repetition-rate sources such as free-electron lasers and other LINAC-based short-pulse sources.
    Optics Express 01/2015; 23(2).
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    ABSTRACT: In this article, we propose and demonstrate a cascaded interferometers structure based on a dual-pass Mach–Zehnder interferometer (DP-MZI) and a Sagnac interferometer (SI) for simultaneous measurement of strain and lateral stress. The cascaded interferometers configuration consists of a SI structure following with a MZI setup. By inserting a section of polarization-maintaining photonic crystal fiber (PM-PCF) in the sensing loop of the SI structure, an inline interference between the two orthogonal polarization modes of PM-PCF, as well as the interference between the sensing arm and the reference arm of the DP-MZI, i.e., the cascaded interferometers with dual interference, are realized. Theoretical study shows that the reflection spectrum of such cascaded interferometers is consisted of two parts: the big spectrum envelope owing to the SI and the fine interference fringes as a result of the DP-MZI. Experimental results show that the SI achieves the sensitivity of lateral stress and strain 1.28 nm/kPa, 0.78 pm/µε, respectively, while the DP-MZI achieves −0.009 nm/kPa and 5.65 pm/µε, demonstrating the ability for dual parameters measurement with high accuracy.
    Optics Express 01/2015; 23(2).
  • [Show abstract] [Hide abstract]
    ABSTRACT: Efficient unconditionally stable FDTD method is developed for the electromagnetic analysis of dispersive media. Toward this purpose, a quadratic complex rational function (QCRF) dispersion model is applied to the alternating-direction-implicit finite-difference time-domain (ADI-FDTD) method. The 3-D update equations of QCRF-ADI-FDTD are derived using Maxwell’s curl equations and the constitutive relation. The periodic boundary condition of QCRF-ADI-FDTD is discussed in detail. A 3-D numerical example shows that the time-step size can be increased by the proposed QCRF-ADI-FDTD beyond the Courant-Friedrich-Levy (CFL) number, without numerical instability. It is observed that, for refined computational cells, the computational time of QCRF-ADI-FDTD is reduced to 28.08 % of QCRF-FDTD, while the L2 relative error norm of a field distribution is 6.92 %.
    Optics Express 01/2015; 23(2).
  • [Show abstract] [Hide abstract]
    ABSTRACT: A new form of double pulse composed of a nanosecond laser and a millisecond laser is proposed for laser machining transparent materials. To evaluate its advantages and disadvantages, experimental investigations are carried out and the corresponding results are compared with those of single millisecond laser. The mechanism is discussed from two aspects: material defects and effects of modifications induced by nanosecond laser on thermal stress field during millisecond laser irradiation. It is shown that the modifications of the sample generated by nanosecond laser improves the processing efficiency of subsequent millisecond laser, while limits the eventual size of modified region.
    Optics Express 01/2015; 23(2).
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    ABSTRACT: We propose an alignment method for the near-zero pretilt angle of liquid crystals (LCs) using polyimide films doped with a UV-curable polymer. The near-zero pretilt angle can be obtained by UV curing of reactive mesogen monomers mixed with planar alignment material while a vertical electric field is applied to an LC cell assembled after the rubbing process. We demonstrated that the pretilt angle can be decreased from 2.390° to 0.082° by employing the proposed method.
    Optics Express 01/2015; 23(2).