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Liu F.,CAS Chengdu Institute of Optics and Electronics | Liu F.,University of Chinese Academy of Sciences | Wu Y.,CAS Chengdu Institute of Optics and Electronics | Wu F.,CAS Chengdu Institute of Optics and Electronics
Optics Express | Year: 2015

We propose a novel phase shifting interferometry from two normalized interferograms with random tilt phase-shift. The determination of tilt phase-shift is performed by extracting the tilted phase-shift plane from the phase difference of two normalized interferograms, and with the calculated tilt phase-shift value the phase distribution can be retrieved from the two normalized frames. By analyzing the distribution of phase difference and utilizing special points fitting method, the tilted phase-shift plane is extracted in three different cases, which relate to different magnitudes of tilts. Proposed method has been applied to simulations and experiments successfully and the satisfactory results manifest that proposed method is of high accuracy and high speed compared with the three step iterative method. Additionally, both open and closed fringe can be analyzed with proposed method. What's more, it cannot only eliminate the small tiltshift error caused by slight vibration in phase-shifting interferometry, but also detect the large tilt phase-shift in phase-Tilting interferometry. Thus, it will relaxes the requirements on the accuracy of phase shifter, and the costly phase shifter may even be useless by applying proposed method in high amplitude vibrated circumstance to achieve high-precision analysis. ©2015 Optical Society of America.


Park H.J.,University of Michigan | Xu T.,University of Michigan | Xu T.,CAS Chengdu Institute of Optics and Electronics | Lee J.Y.,University of Michigan | And 2 more authors.
ACS Nano | Year: 2011

Color filters are indispensable in most color display applications. In most cases, they are chemical pigment-based filters, which produce a particular color by absorbing its complementary color, and the absorbed energy is totally wasted. If the absorbed and wasted energy can be utilized, e.g., to generate electricity, innovative energy-efficient electronic media could be envisioned. Here we show photonic nanostructures incorporated with photovoltaics capable of producing desirable colors in the visible band and utilize the absorbed light to simultaneously generate electrical powers. In contrast to the traditional colorant-based filters, these devices offer great advantages for electro-optic applications. © 2011 American Chemical Society.


Feng Q.,CAS Chengdu Institute of Optics and Electronics | Feng Q.,Southwestern Institute of Physics | Pu M.,CAS Chengdu Institute of Optics and Electronics | Hu C.,CAS Chengdu Institute of Optics and Electronics | Luo X.,CAS Chengdu Institute of Optics and Electronics
Optics Letters | Year: 2012

We propose a broadband infrared absorber by engineering the frequency dispersion of metamaterial surface (metasurface) to mimic an ideal absorbing sheet. With a thin layer of structured nichrome, a polarizationindependent absorber with absorption larger than 97% is numerically demonstrated over a larger than one octave bandwidth. It is shown that the bandwidth enhancement is related with the transformation of the Drude model of free electron gas in metal film to the Lorentz oscillator model of a bound electron in the structured metallic surface. We believe that the concept of dispersion engineering may provide helpful guidance for the design of a broadband absorber. © 2012 Optical Society of America.


Jing H.,CAS Chengdu Institute of Optics and Electronics | King C.,University College London | Walker D.,University College London
Optics Express | Year: 2010

The Extremely Large Telescope (ELT) projects presuppose segmented primary mirrors. The metrology of the off-axis aspherical segments is particularly challenging in terms of global form, mid spatial frequencies and matching of the base-radius and conic constant. We propose to use a swing arm profilometer (SAP) to provide verification independent of interferometry. In this paper we present results of a simulation of the swing arm profilometer as applied to mirror segments, and experimental verification of the simulation using a prototype instrument. ©2010 Optical Society of America.


Jing H.,CAS Chengdu Institute of Optics and Electronics | King C.,University College London | Walker D.,University College London
Optics Express | Year: 2010

We present a novel method to accurately measure 3D polishing influence functions by using a swing arm profilometer (SAP) and a laser tracker. The laser tracker is used to align the SAP and measure the parameters of the SAP setup before measuring the influence function. The instruments and the measurement method are described, together with measurement uncertainty analysis. An influence function deliberately produced with asymmetric form in order to create a challenging test is measured, and compared with that of a commercial 3D profilometer. The SAP result is 48.2μm in PV, 7.271mm3 in volume. The 3D profilometer result is 48.4μm in PV, 7.289mm3 in volume. The forms of the two results show excellent correlation. This gives confidence of the viability of the SAP method for larger influence functions out of range of the commercial instrument. © 2010 Optical Society of America.


Luo X.G.,CAS Chengdu Institute of Optics and Electronics
Science China: Physics, Mechanics and Astronomy | Year: 2015

Metasurfaces are artificially structured thin films with unusual properties on demand. Different from metamaterials, the metasurfaces change the electromagnetic waves mainly by exploiting the boundary conditions, rather than the constitutive parameters in three dimensional (3D) spaces. Despite the intrinsic similarities in the operational principles of metasurfaces, there is not a universal theory available for the understanding and design of these devices. In this article, we propose the concept of metasurface waves (M-waves) and provide a general theory to describe the principles of such waves. Most importantly, it is shown that the M-waves share some fundamental properties such as extremely short wavelength, abrupt phase change and strong chromatic dispersion, which making them different from traditional bulk waves. We show that these properties can enable many important applications such as subwavelength imaging and lithography, planar optical devices, broadband anti-reflection, absorption and polarization conversion. Our results demonstrated unambiguously that traditional laws of diffraction, refraction, reflection and absorption can be overcome by using the novel properties of M-waves. The theory provided here may pave the way for the design of new electromagnetic devices and further improvement of metasurfaces. © 2015, Science China Press and Springer-Verlag Berlin Heidelberg.


Fu Y.,University of Electronic Science and Technology of China | Fu Y.,CAS Chengdu Institute of Optics and Electronics | Zhou X.,University of Electronic Science and Technology of China
Plasmonics | Year: 2010

Four types of plasmonic lenses for the purpose of superfocusing designed on the bases of approximate negative refractive index concept, subwavelength metallic structures, waveguide mode were introduced, and curved chains of nanoparticles, respectively, were introduced. Imaging mechanism, fabrication, and characterization issues were presented. Theoretical analyses of the illumination with different polarization states on focusing performance of the plasmonic lenses were given also. In addition, a hybrid Au-Ag plasmonic lens with chirped slits for the purpose of avoiding oxidation of Ag film was presented. © 2010 Springer Science+Business Media, LLC.


Wu M.,CAS Chengdu Institute of Optics and Electronics | Peng X.,CAS Chengdu Institute of Optics and Electronics
AEU - International Journal of Electronics and Communications | Year: 2010

In background subtraction, it is challenging to detect foreground objects in the presence of dynamic background motions. The paper proposes two new algorithms to this problem by improving the codebook model with the incorporation of the spatial and temporal context of each pixel. The spatial context involves the local spatial dependency between neighboring pixels, and the temporal context involves the preceding detection result. Only the spatial context is incorporated into the first algorithm which makes the background representation more compact than the standard codebook. The second algorithm explicitly models the spatio-temporal context with a Markov random field model, thus achieving more accurate foreground detection. Extensive experiments on several dynamic scenes are conducted to compare the two proposed algorithms with each other and with the standard codebook algorithm. © 2009 Elsevier GmbH. All rights reserved.


Kaplan A.F.,University of Michigan | Kaplan A.F.,CAS Chengdu Institute of Optics and Electronics | Xu T.,University of Michigan | Jay Guo L.,University of Michigan
Applied Physics Letters | Year: 2011

We propose a nanostructured color filter based on a metallic resonant waveguide structure capable of extremely high transmission efficiency. As an experimental demonstration, a blue and a red device were fabricated over a large area using nanoimprint lithography. Achieving transmission as high as 90 with a variable transmission bandwidth, these devices exhibit desirable features for numerous color filter applications. © 2011 American Institute of Physics.


Luo J.,CAS Chengdu Institute of Optics and Electronics
Sensors (Basel, Switzerland) | Year: 2013

A silver nanoparticle-modified evanescent field optical fiber sensor based on a MEMS microchannel chip has been successfully fabricated. Experimental results show that the sensor response decreases linearly with increasing concentration of analyte. Over a range of methylene blue concentrations from 0 to 0.4 μmol/mL, the sensor response is linear (R = 0.9496). A concentration variation of 0.1 μmol/mL can cause an absorbance change of 0.402 dB. Moreover, the optical responses of the same sensing fiber without decoration and modified with silver nanoparticles have also been compared. It can be observed that the output intensity of the Ag nanoparticle-modified sensor is enhanced and the sensitivity is higher. Meanwhile, the absorbance spectra are found to be more sensitive to concentration changes compared to the spectra of the peak wavelength.

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