48,607 results match your criteria Applied optics[Journal]


Three-degrees-of-freedom laser interferometer based on differential wavefront sensing with wide angular measurement range.

Appl Opt 2019 Jan;58(3):723-728

We present a three-degrees-of-freedom laser interferometer based on differential wavefront sensing with a wide angular measurement range. To obtain measurement signals with a high AC/DC ratio and improve the linearity of differential wavefront sensing in a wide range angular displacement measurement, a fiber bundle instead of a quadrant photodiode is applied to receive the interference light. Meanwhile, a decoupled algorithm with quadratic correction derived by the ray tracing method and kinematic analysis is detailed in the case of the wide range angular displacement. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000723DOI Listing
January 2019

Supernumerary bows: caustics of a refractive sphere and analysis of the relative overall Gouy phase shift of supernumerary rays.

Appl Opt 2019 Jan;58(3):712-722

The modified Young's theory of interference related to supernumerary rainbows is based on a difference of 90° in the Gouy phase shifts for the parallel rays producing these bows. An observation screen placed at a given distance from a refractive sphere illuminated by a point source of light should also show supernumerary screen bows. An extensive description and analysis of the caustics involved are given. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000712DOI Listing
January 2019

High-transmission polarization-dependent active plasmonic color filters.

Appl Opt 2019 Jan;58(3):704-711

Plasmonic color filters, exhibiting great promise as an alternative for existing colorant-based filters, often only output one fixed color. Developing active color filters with controllable color output will lead to more compact color filter-based devices. In this paper, we present an approach to achieve active color filtering with a polarization-dependent plasmonic structural color filter, which comprises arrays of asymmetric cross-shaped nanoapertures in an ultrathin film of silver. Read More

View Article

Download full-text PDF

Source
https://www.osapublishing.org/abstract.cfm?URI=ao-58-3-704
Publisher Site
http://dx.doi.org/10.1364/AO.58.000704DOI Listing
January 2019
3 Reads

Security analysis and enhancement of a cryptosystem based on phase truncation and a designed amplitude modulator.

Authors:
Y Xiong A He C Quan

Appl Opt 2019 Jan;58(3):695-703

In this paper, the security of a cryptosystem based on phase truncation and a designed amplitude modulator (AM) is evaluated. In the cryptosystem, an undercover AM used as an additional key is added to modulate the amplitude information of the spectrum in the Fourier plane. Compared to the conventional phase-truncated Fourier transform (PTFT)-based cryptosystem, the security of the cryptosystem is improved by increasing the number of unknown keys. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000695DOI Listing
January 2019

Suppressing residual amplitude modulation to the 10 level in optical phase modulation.

Appl Opt 2019 Jan;58(3):690-694

Residual amplitude modulation is one of the major stability-degrading factors in many precision measurements. Using an electro-optic (EO) crystal with wedged input and output surfaces is an effective way to suppress residual amplitude modulation. Here the mechanism of residual amplitude modulation in this approach is investigated. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000690DOI Listing
January 2019
2 Reads

Multi-point fiber refractometer using Fresnel reflection and a coherent optical frequency-domain multiplexing technique.

Appl Opt 2019 Jan;58(3):684-689

We demonstrate a simple multi-point refractometer based on the coherent optical frequency-domain multiplexing technique. As local refractive index sensors, interferometers of different lengths formed between cleaved fiber tips and reference weak reflectors are employed. Referent reflectors were fabricated by splicing into lead SMF-28 fiber a very short section of hollow optical fiber using a standard fiber splicer and a cleaver with an optical microscope. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000684DOI Listing
January 2019

Design of confocal off-axis two-mirror system for head-up display.

Appl Opt 2019 Jan;58(3):677-683

We present a new optical system for a combiner-type head-up display (HUD) without any asymmetrical elements by employing a confocal, off-axis, two-hyperboloid mirror as an aberration corrector. From an off-axial aberration analysis, we initially obtain an off-axis two-mirror system corrected for linear astigmatism and spherical aberration by configuring its parameters to satisfy the confocal condition. In addition, to compensate the down angle in the HUD, the image display plane is tilted to satisfy the Scheimpflug condition. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000677DOI Listing
January 2019
1 Read

Theory and method for large electric field intensity enhancement in the nanoantenna gap.

Appl Opt 2019 Jan;58(3):670-676

We first investigate the field intensity in the nanoantenna gap as a function of common antenna properties including polarization, input resistance, and gain. This function provides us a method on how to effectively enhance the field intensity. In the case of polarization matched to the incident wave, the nanoantenna should have both large input resistance and high gain in the arrival direction. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000670DOI Listing
January 2019
2 Reads

Intercomparison of airborne multi-angle polarimeter observations from the Polarimeter Definition Experiment.

Appl Opt 2019 Jan;58(3):650-669

In early 2013, three airborne polarimeters were flown on the high altitude NASA ER-2 aircraft in California for the Polarimeter Definition Experiment (PODEX). PODEX supported the pre-formulation NASA Aerosol-Cloud-Ecosystem (ACE) mission, which calls for an imaging polarimeter in polar orbit (among other instruments) for the remote sensing of aerosols, oceans, and clouds. Several polarimeter concepts exist as airborne prototypes, some of which were deployed during PODEX as a capabilities test. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000650DOI Listing
January 2019
2 Reads

Design of off-axis three-mirror systems with ultrawide field of view based on an expansion process of surface freeform and field of view.

Appl Opt 2019 Jan;58(3):609-615

Unobscured reflective optical systems with a wide field of view (FOV) have significant application values. However, the aberration increases with the increase of the system FOV, so a wide FOV system is difficult to design. In this paper, a design method that is effective in achieving off-axis three-mirror systems with ultrawide FOV is proposed. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000609DOI Listing
January 2019

Dual-directional shearography based on a modified common-path configuration using spatial phase shift.

Appl Opt 2019 Jan;58(3):593-603

This paper describes a dual-directional shearography system to address the issue of two-dimensional characterization of the surface strain. A common-path configuration coupled with an additional light path is used to provide the shearing in two directions. One of the three interfering beams is shared by both directional shearograms to improve the light efficiency and enhance the robustness of the system. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000593DOI Listing
January 2019
1 Read

Field-enhanced nanofocusing of radially polarized light by a tapered hybrid plasmonic waveguide with periodic grooves.

Appl Opt 2019 Jan;58(3):588-592

This study reports the field-enhanced nanofocusing of radially polarized light by tapered hybrid plasmonic waveguide (THPW) with periodic grooves. The THPW consists of a conical high-index dielectric cone, a sandwiched low-index dielectric thin layer, and a metal cladding. The axially symmetric 3D finite element method is used to investigate the nanofocusing effect. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000588DOI Listing
January 2019

Optical athermalization in the visible waveband using the 1+∑ method.

Appl Opt 2019 Jan;58(3):635-641

In this paper, the 1+∑ method, which is based on the double-lens equivalent model, is proposed to achieve optical athermalization in the visible waveband. The glass in the system was replaced by calculating and analyzing the synthetic weights of the thermal power and chromatic power. A complex aerial camera with long focal length was designed over a temperature difference of 100°C. Read More

View Article

Download full-text PDF

Source
https://www.osapublishing.org/abstract.cfm?URI=ao-58-3-635
Publisher Site
http://dx.doi.org/10.1364/AO.58.000635DOI Listing
January 2019
3 Reads

Thermal emission spectroscopy for single nanoparticle temperature measurement: optical system design and calibration.

Appl Opt 2019 Jan;58(3):642-649

We discuss the design of an optical system that allows measurement of 600-1650 nm emission spectra for individual nanoparticles (NPs), laser-heated in an electrodynamic trap in controlled atmospheres. An approach to calibration of absolute intensity versus wavelength for very low emission intensities is discussed, and examples of NP graphite and carbon black spectra are used to illustrate the methodology. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000642DOI Listing
January 2019
1 Read

Rapid measurement of the fourth-order texture coefficient by laser ultrasonic surface acoustic waves based on a neural network expert system.

Appl Opt 2019 Jan;58(3):626-634

In anisotropic materials, texture components and orientation density directly affect the surface acoustic waves' (SAW) velocity dispersion and SAW velocity variation. In this paper, a texture feature recognition and analysis system for a neural network is constructed based on the corresponding characteristics of texture components and orientation density and SAW velocity dispersion and variation by combining laser ultrasound technology with the partial texture analysis method, which is used for the identification and analysis of texture type and feature. At the same time, based on the relationship between surface wave velocity and the fourth-order texture coefficient, an expert system for accurate prediction of the fourth-order texture coefficient is constructed. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000626DOI Listing
January 2019
1 Read

Analysis of energy monitoring for a double-pulsed CO integrated path differential absorption lidar at 1.57  μm.

Appl Opt 2019 Jan;58(3):616-625

For double-pulsed 1.57 μm integrated path differential absorption lidar, the transmitted pulse energy measurement is an important factor that can influence the uncertainty of CO concentration measurement. An energy monitoring experiment was performed to determine how to improve the measurement precision of the transmitted pulse energy. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000616DOI Listing
January 2019

Rotation velocity measurement based on self-mixing interference with a dual-external-cavity single-laser diode.

Appl Opt 2019 Jan;58(3):604-608

A novel Doppler velocity measurement method based on laser self-mixing interference with two parallel optical external cavities is investigated. In this method, the target object rotation velocity can be measured by the sum of two Doppler frequency shifts, which can be extracted by fast Fourier transform without setting and measuring incident angles. This study highlights the validity of the proposed method through a theoretical model analysis. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000604DOI Listing
January 2019
1 Read

SFDR and gain enhancement in photonic downconversion link by linearization and full spectrum utilization.

Appl Opt 2019 Jan;58(3):579-587

In this work, an all-optical scheme to improve the gain and linearity of the downconverted analog photonic link is proposed and verified. We utilize the different electro-optic coefficients of the z-cut LiNbO phase modulator to realize the suppression of the third-order intermodulation distortion. On this basis, the link gain is improved by reusing optical carrier and lower sidebands. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000579DOI Listing
January 2019
1 Read

Limiting factors for optical switching using nano-structured graphene-based field effect transistors.

Appl Opt 2019 Jan;58(3):571-578

Thanks to the particular band diagram of graphene, it is recognized as a promising material for developing optoelectronic devices at the nano-scale. In this paper, a functional stack comprised of graphene and other materials is numerically investigated to extract the related capacitance-voltage curve by taking into account practical considerations regarding the nano-structured electronic devices. Polycrystalline silicon gates are used as electrical contacts in this stack, which are considered as semiconductor materials rather than metal contacts owing to the nano-scale dimensions of the constitutive materials. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000571DOI Listing
January 2019
2 Reads

Spectroscopic investigation of molecular formation in laterally colliding laser-produced carbon plasmas.

Appl Opt 2019 Jan;58(3):561-570

We report detailed spectroscopic investigation of carbon dimer production in the stagnation layer formed due to laterally colliding plasma plumes under vacuum and N ambience. Two spatially separated Nd:YAG laser pulses are used to generate plasma plumes in close proximity to a solid graphite target. A comparative optical emission spectroscopic study of a stagnation layer and a single carbon plasma plume is carried out in order to find the optimum experimental conditions for carbon dimer (C) production. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000561DOI Listing
January 2019

Image-spherizing-based planeness detecting method for a micro-channel plate.

Appl Opt 2019 Jan;58(3):554-560

Based on the mathematical models proposed by the image spherizing algorithm, a novel planeness detecting method for a micro-channel plate (MCP) is presented. After describing the theory of the image spherizing algorithm, a straight line image is chosen as a standard picture, and the imaging simulation for a deformed MCP is performed. According to the simulated results, the deformation characteristic of the MCP and the mechanism of the image twisting phenomenon were analyzed. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000554DOI Listing
January 2019
1 Read

Control of resonance mode using a fine-structured grating: toward a high resolving power filter.

Appl Opt 2019 Jan;58(3):549-553

A band-stop filter with high resolving power is designed for mid-infrared spectroscopic sensing and imaging applications. By utilizing a truncated grating consisting of multiple gold nanowires in each unit cell of the periodic structure, compression of the stop bandwidth and improvement of the resonance extinction are realized simultaneously. It shows only a single stop band at ∼4. Read More

View Article

Download full-text PDF

Source
https://www.osapublishing.org/abstract.cfm?URI=ao-58-3-549
Publisher Site
http://dx.doi.org/10.1364/AO.58.000549DOI Listing
January 2019
4 Reads

Comparison of different schemes for stimulated Brillouin scattering enhancement.

Appl Opt 2019 Jan;58(3):545-548

A comparison of different schemes to enhance stimulated Brillouin Scattering (SBS) in single-mode optical fiber is performed. Specifically, we evaluated SBS generation efficiency in a 3 km length fiber with and without power recycling versus the same fiber placed in a ring resonator and in a ring resonator in a recycling configuration. For the latter case, a large number of both odd and even higher-order Stokes and anti-Stokes harmonics is generated. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000545DOI Listing
January 2019
1 Read

Planar antenna array as a highly sensitive terahertz sensor.

Appl Opt 2019 Jan;58(3):540-544

In this paper, a planar comb-shaped antenna array for terahertz sensing based on the excitation of spoof surface plasmon modes is proposed. The structure is constructed by an array of three periodic rectangular grooves perforated through metal stripes on top of a silicon substrate. The effective detection of lactose is given as an example to demonstrate the ability of this structure to enhance detection sensitivity. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000540DOI Listing
January 2019

Temperature sensor based on multi-layer MoS coated etched fiber Bragg grating.

Appl Opt 2019 Jan;58(3):535-539

The development of an etched fiber Bragg grating (eFBG)-based temperature sensor with a uniform multi-layer molybdenum-di-sulphide (MoS) coating is presented in this paper. Multi-layer MoS has been coated on clad etched FBG sensors by DC magnetron sputtering of molybdenum (Mo) and subsequent sulfurization. The dependence of temperature sensitivity on the coating thickness of MoS on eFBGs has been tested from room temperature to 100°C. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000535DOI Listing
January 2019

Refractive index sensor in eccentric fiber Bragg gratings using a point-by-point IR femtosecond laser.

Appl Opt 2019 Jan;58(3):528-534

In this paper, we demonstrate point-by-point inscription of eccentric fiber Bragg grating (EFBG) in conventional single-mode fiber (Corning SMF-28) with second-order Bragg resonances within the C-band using an IR femtosecond laser. Highly localized fiber Bragg gratings can be inscribed point-by-point with focused ultrashort pulses. EFBGs are localized close to the core-cladding interface, yielding strong cladding mode resonance couplings and high photoinduced birefringence. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000528DOI Listing
January 2019
1 Read

Reconstruction method based on the Hilbert fractal curve recovery sequence in a Fourier ptychography microscope.

Appl Opt 2019 Jan;58(3):517-527

Many Fourier ptychography microscopy techniques have been proposed to achieve higher recovery accuracy in the past few years, yet it is little known that their reconstructed quality is also dependent on the choice of recovery sequence, which is important for fast solution convergence during the Fourier ptychography reconstruction process. In this paper, we propose to use the Hilbert fractal curve, which is one of the most representative of classic space-filling curves, as a new kind of recovery sequence of mesh LED arrays and validate its effectiveness and robustness with both simulated and real experiments. Results show that the Hilbert fractal curve as the recovery sequence is a better choice for periodic LED arrays, compared with raster line, spiral line, and wave-shaped-curve three-recovery sequences. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000517DOI Listing
January 2019
1.784 Impact Factor

Extended light-source-based lensless microscopy using constrained and regularized reconstruction.

Appl Opt 2019 Jan;58(3):509-516

Lensless microscopy is a simple, portable, and cost-effective method of microscopy. It has been extensively investigated with coherent light sources such as laser setups or partially coherent light sources such as an LED filtered with a pinhole aperture. The coherence of light has a direct influence on the resolution of the reconstructed object. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000509DOI Listing
January 2019

3D shape shearography technique for surface strain measurement of free-form objects.

Appl Opt 2019 Jan;58(3):498-508

Shearography is a non-destructive testing technique that provides full-field surface strain characterization. Previous inspection of flat objects or simple geometric shapes has been reported. However, real-life objects especially in aerospace, transport, or cultural heritage are not flat, but their inspection with shearography is of interest for both hidden defect detection and material characterization. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000498DOI Listing
January 2019
1 Read

Design of stable and high-efficiency graphene-based polarizers for oblique angle of incidence in terahertz frequency.

Appl Opt 2019 Jan;58(3):492-497

Most investigations of polarizers consider a normal angle of incidence only. This paper expands our investigation to also include an oblique angle of incidence. Essential problems are encountered for an oblique angle of incidence: there is an upward shift of the center frequency, and the impedance match gets worse as the angle of incidence increases. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000492DOI Listing
January 2019

Compact reflective system for ideal imaging concentration.

Appl Opt 2019 Jan;58(3):485-491

We propose a new design principle for optimal concentration of light with small diffusivity based on the conservation of local brightness in passive optical transformations. A coordinate transformation is applied on the incoming rays to compensate for the variations in local brightness by the focusing stage. We apply this analytic design for a compact reflective configuration for ideal imaging concentration of diffuse light such as sunlight in one dimension on an elongated target with arbitrary cross-sectional shape at the thermodynamic limit. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000485DOI Listing
January 2019

Laser micromachining of periodic surface radius change on the optical fiber circumference.

Appl Opt 2019 Jan;58(1):189-196

In this paper, we are showing that holes and marking spots with sizes that are comparable to the wavelength of a CO laser at λ=10.6  μm can be achieved reproducibly on a conventional optical fiber SMF28 when it is positioned at the focal point. Some theory on Gaussian beam propagation is briefly reviewed and readily applied to drill a fiber on its axis near the focal point. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000189DOI Listing
January 2019
1 Read

Crystal structure dependence of the breathing vibration of individual gold nanodisks induced by the ultrafast laser.

Authors:
Yong Gan Zheng Sun

Appl Opt 2019 Jan;58(1):213-218

The ultrafast laser-excited breathing vibrations of gold nanodisks with different crystal structures have been studied via atomistic simulations. The vibrational periods and damping rates of nanodisks are obtained by the analysis of the simulated transient responses of nanodisks. It is shown that the breathing period of nanodisks is considerably dependent on their crystal structure, which is contrary to the cases for the breathing vibration of metal nanospheres and nanorods. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000213DOI Listing
January 2019
5 Reads

Reconstruction of two-dimensional velocity distribution in scramjet by laser absorption spectroscopy tomography.

Appl Opt 2019 Jan;58(1):205-212

We propose a method to reconstruct the two-dimensional (2D) velocity distribution of flow fields by laser absorption spectroscopy tomography. A mathematic model is established to reveal the dependence of spectral absorbance on line-of-sight velocity distribution. Then, with multiple laser beams from different angular views covering the region of interest, a nonlinear equation set of 2D velocity distribution is established according to the model. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000205DOI Listing
January 2019
1 Read

Coherence control of entanglement dynamics of two-mode Gaussian state via Raman driven quantum beat laser using Simon's criterion.

Appl Opt 2019 Jan;58(1):197-204

We study the entanglement dynamics of two-mode Gaussian state (TMGS) in a quantum beat laser driven by two classical fields in Raman configuration using Simon's criterion of quantum state separability. The two modes of the cavity field are considered initially in general single-mode Gaussian states. The effect of the non-classicality, purity, and relative phase of the cavity modes on the entanglement phenomenon is studied thoroughly. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000197DOI Listing
January 2019
2 Reads

Thin lens aberrations for anamorphic lenses.

Appl Opt 2019 Jan;58(1):182-188

This paper provided thin lens aberrations for anamorphic lenses, including the central thin lens aberrations, the central Lagrange invariant shift, the central conjugate shift, and the central pupil shift. Based on thin lens theory and the paraxial lens module, the aberration of the anamorphic lens system can be easily corrected. The central Lagrange invariant shift can be used for aberration correction for an anamorphic zoom lens system. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000182DOI Listing
January 2019
2 Reads

Enhanced circular dichroism of tilted zigzag-shaped nanohole arrays.

Appl Opt 2019 Jan;58(1):177-181

Circular dichroism (CD) of nanostructures is in great demand for applications in biological molecules, photocurrent devices, and photocatalysis. Planar nanostructures can be prepared in a concise manner, and their CD effects have gained much research interest. In this study, tilted zigzag-shaped nanohole (TZSN) arrays are proposed, and the CD effect is studied by the finite element method. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000177DOI Listing
January 2019
1 Read

Recording digital color information on transparent polyethylene films by thermal treatment.

Appl Opt 2019 Jan;58(1):172-176

This study characterizes the use of transparent low-density polyethylene laminate films for the purpose of recording digital information in the form of linear and color two-dimensional matrix codes that are distinguishable in polarized light. Color characteristics of multilayer laminated materials made from polyethylene and heat treatment methods for changing their coloring are examined. The contribution of the number of multilayer film interfaces to the lightness and color of the laminate is shown. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000172DOI Listing
January 2019
1 Read

Exo-atmospheric infrared objects classification using recurrence-plots-based convolutional neural networks.

Appl Opt 2019 Jan;58(1):164-171

Object discrimination plays an important role in infrared (IR) imaging systems. However, at long observing distance, the presence of detector noise and absence of robust features make exo-atmospheric object classification difficult to tackle. In this paper, a recurrence-plots-based convolutional neural network (RP-CNN) is proposed for feature learning and classification. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000164DOI Listing
January 2019
3 Reads

Optical characterization and adaptive optics correction of polymer adaptive lens aberrations.

Appl Opt 2019 Jan;58(1):158-163

Adaptive lenses based on fluid-filled polymer membranes allow for great simplification of optical systems providing large focal length variation and reduction of size, weight, and power consumption. However, aberrations can reduce their optical quality and, for some demanding applications, their correction by means of adaptive optics implies increased complexity, especially if reflective wavefront correctors are used. In this work, we characterize two adaptive lenses in terms of optical power and aberrations. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000158DOI Listing
January 2019
1 Read

Double square rings with different dimensions produce multiple absorption bands.

Appl Opt 2019 Jan;58(1):152-157

The quantity of absorption bands is traditionally less than the quantity of resonator subunits. Based on the absorption theory of electromagnetic resonance, three-millimeter-wave metamaterial absorbers (MWMAs) based on periodic resonators with double square rings (DSRs) are proposed, discussed, fabricated, and measured. Multiple absorption bands including two, three, and four bands can be effectively achieved by adjusting the dimensions of the DSRs. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000152DOI Listing
January 2019
1 Read

Plasmonic-induced absorption based on an end-coupled combined resonance system of a semiannular cavity and rectangular cavity.

Appl Opt 2019 Jan;58(1):43-49

A semiannular rectangular composite cavity structure based on metal-insulator-metal waveguides is proposed. By adding a rectangular cavity at a suitable position around the semiannular cavity (SAC), a single analogous plasmonic-induced absorption (PIA) effect is achieved at the expected mode of the SAC structure. After adding two rectangular cavities together in the SAC system, dual analogous PIA effects for both modes can be realized simultaneously. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000043DOI Listing
January 2019
1 Read

Low-noise and high-gain of stimulated Brillouin amplification via orbital angular momentum mode division filtering.

Appl Opt 2019 Jan;58(1):147-151

We demonstrate a Brillouin amplifier scheme by using orbital angular momentum mode division filtering, which is able to amplify the weak optical signals with low noise and high gain. The system retains the advantages of a conventional collinear Brillouin amplifier structure, and employs a liquid-crystal spatial light modulator to generate distinguishable degree-of-freedom of beams. As we all know, the noise mainly derives from the unwanted coupling in stimulated Brillouin scattering (SBS) processes, which severely limits the amplifier's performances. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000147DOI Listing
January 2019
2 Reads

Weighted-least-squares multi-filter phase imaging with partially coherent light: characteristics of annular illumination.

Appl Opt 2019 Jan;58(1):137-146

Multi-filter phase imaging with partially coherent light (MFPI-PC) is a promising microscopic quantitative phase imaging (QPI) method that measures the phase of a transparent object. In the present work, a weighted-least-squares version is developed and applied to the important case of annular illumination. The resulting improved algorithms have largely solved the noise magnification problem associated with the original MFPI-PC in annular illumination. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000137DOI Listing
January 2019
2 Reads

Improvements to dispersed reference interferometry: beyond the linear approximation.

Appl Opt 2019 Jan;58(1):131-136

Interferometric instruments with dispersion introduced in the reference arm have previously been created, as the controlled dispersion can be used to generate a signal that contains a clearly identifiable point, the location of which relates to the position of the scattering surface in the measurement arm. In the following, we illustrate that the linear approximations that have been used previously can lead to significant errors, and that second-order terms need to be included in order to correct this. These corrections are vital if these instruments are to be used for metrological applications. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000131DOI Listing
January 2019
1 Read

Nine-sector three-stage Fresnel lens concentrator.

Appl Opt 2019 Jan;58(1):122-130

In this paper, we design a three-stage Fresnel lens concentrator with a low f number. The proposed concentrator consists of a primary optical element (POE) and a second optical element (SOE). The nine-sector three-stage Fresnel lens is composed of three types of triangular prisms: the refractive triangular prism, single total internal reflection triangular prism, and double total internal reflection triangular prism. Read More

View Article

Download full-text PDF

Source
https://www.osapublishing.org/abstract.cfm?URI=ao-58-1-122
Publisher Site
http://dx.doi.org/10.1364/AO.58.000122DOI Listing
January 2019
4 Reads

Tunable defect modes of one-dimensional photonic crystals containing a Dirac semimetal-based metamaterial defect layer.

Appl Opt 2019 Jan;58(1):94-101

The transmission properties of one-dimensional photonic crystals (PCs) containing a metamaterial (MM) defect layer are investigated using the transfer matrix method. The MM is composed of alternating layers of a dielectric material and a Dirac semimetal (DS) material. Numerical results show that the defective PCs possess a tunable defect mode, which is significantly dependent on the Fermi level of the DS as well as the structural parameters of the MM defect layer. Read More

View Article

Download full-text PDF

Source
https://www.osapublishing.org/abstract.cfm?URI=ao-58-1-94
Publisher Site
http://dx.doi.org/10.1364/AO.58.000094DOI Listing
January 2019
5 Reads

Total internal reflection shell for light-emitting diode bulbs.

Appl Opt 2019 Jan;58(1):87-93

A total internal reflection (TIR) shell capable of generating illuminating light with a wide-angle distribution from light-emitting diodes (LEDs) is proposed. The TIR shell can be used to create an LED light bulb with enclosed heat dissipaters to release the heat generated by the LEDs. The TIR shell has light-scattering areas on its inner surface and a mirror-polished free-form outer surface that can guide all rays emitted from the LEDs to the scattering areas by the TIR. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000087DOI Listing
January 2019
3 Reads

Microstructured light guiding plate for single-sided light emission as light source for room illumination.

Appl Opt 2019 Jan;58(1):76-86

Microstructured light guiding plates (LGP) open up new capabilities in the design of energy efficient and flexible light sources for room lighting. One desirable application is the illumination of office rooms by LGPs located mainly at the façade. Starting with the requirements of an ideal light distribution curve for uniform room lighting, suitable optical microstructures have been designed and investigated by numerical ray tracing methods to be integrated in façade elements. Read More

View Article

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.58.000076DOI Listing
January 2019
3 Reads

Color holographic display using single chip LCOS.

Appl Opt 2019 Jan;58(1):69-75

An algorithm for calculating a phase-only computer-generated hologram (CGH) for 3D color display using single chip liquid crystal on silicon (LCOS) is proposed. As an evolution of the G-S iteration, the proposed algorithm was obtained by replacing the Fresnel diffraction of single wavelength in the G-S algorithm with a color Fresnel diffraction process. Moreover, combined with "Ping-Pong" iteration, this algorithm was used to calculate 3D color holograms. Read More

View Article

Download full-text PDF

Source
https://www.osapublishing.org/abstract.cfm?URI=ao-58-1-69
Publisher Site
http://dx.doi.org/10.1364/AO.58.000069DOI Listing
January 2019
6 Reads