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We present a non-contact technique for measuring objects in motion with a laser tracker without the laser tracker needing to follow the object. This method allows the dynamic state of an object to be measured while, to the laser tracker the object appears
The dataset contains several MATLAB files and input files for the software package JCMsuite that enable the modeling of optical imaging of finite multi-line arrays. (Certain commercial materials are identified in order to specify the experimental procedure
Mark Alexander Henn, Bryan M. Barnes, Hui Zhou, Martin Y. Sohn, Richard M. Silver
The full 3-D scattered field above finite sets of features has been shown to contain a continuum of spatial frequency information, and with novel optical microscopy techniques and electromagnetic modeling, deep-subwavelength geometrical parameters can be
Luis Miaja Avila, Galen C. O'Neil, Young Il Joe, Bradley K. Alpert, Niels Damrauer, William B. Doriese, Steven Fatur, Joseph W. Fowler, Gene C. Hilton, Ralph Jimenez, Carl D. Reintsema, Daniel R. Schmidt, Kevin L. Silverman, Daniel S. Swetz, Hideyuki Tatsuno, Joel N. Ullom
Chemical reactions driven by light are fundamental to biology and a source of inspiration for engineering materials to perform tasks such as solar energy harvesting and data storage. Observing and understanding photodynamics requires experimental tools
This study investigates methods for characterizing materials that are mixtures of granular solids, or mixtures of liquids, which may be linear or non-linear. Linear mixtures of materials in a scene are often the result of areal mixing, where the pixel size
Catherine C. Cooksey, Georgi T. Georgiev, Leibo Ding, James J. Butler
Satellite instruments operating in the solar wavelength region require accurate and precise determination of the optical properties of their diffusers used in pre-flight and post-flight calibrations. The majority of recent and current space instruments use
Trajectories of spherical dielectric particles carried across an optical standing wave by a flowing medium areinvestigated. Trajectories are determined by a three-dimensional Monte Carlo calculation that includes drag forces, Brownian motion, and optical
Recently, as part of a study of the ability of a Gaussian standing-wave interference field to sort small dielectric particles entrained in a moving fluid, we implemented a two-length-scale method to determine the trajectories of the particles. In the first
Recently, as part of a study of the ability of a Gaussian standing-wave interference field to sort small dielectric spheres entrained in a moving fluid, we implemented a two-length-scale method to determine the trajectories of the particles. In the first
Alexander Peterson, Michael Halter, Anne Plant, John Elliott
Surface plasmon resonance imaging (SPRI) allows real-time label-free imaging based on index of refraction, and changes in index of refraction at an interface. SPRI can be carried out on a microscope by launching light into a sample, and collecting
Sung Kim, David R. Novotny, Joshua A. Gordon, Jeffrey R. Guerrieri
A free-space measurement method is presented for the characterization of low-loss dielectric materials at millimeter-wave (MMW) frequencies that does not require any assumption of a priori knowledge of the sample thickness. The present method first employs
We consider the effect of volume diffusion on measurements of the bidirectional scattering distribution function (BSDF) when a finite distance is used for the solid angle defining aperture. We derive expressions for correction factors that can be used when
T D. Shoji, W Xie, Kevin L. Silverman, Ari Feldman, Todd E. Harvey, Richard Mirin, Thomas Schibli
Low-noise, high-repetition-rate mode-locked solid-state lasers are attractive for precision measurement and microwave generation, but the best lasers in terms of noise performance still consist of complex, bulky optical setups, which limits their range of
Noncentrosymmetric potassium dihydrogen phosphate (KH2PO4 or KDP) in the tetragonal crystal phase is arguably the most extensively studied nonlinear optical crystal in history. It has prolific applications ranging from simple laser pointers to laser
Paul Witherell, Ibrahim Assouroko, Roh Byeong-Min, Timothy Simpson, Soundar Kumara
Additive manufacturing (AM) is creating renewed interest in manufacturing thanks to the freedom it provides to design and innovate. One of the biggest challenges in AM is inadequate repeatability in product quality and reliability of the process for
Broadband coherent anti-Stokes Raman scattering (BCARS) microspectroscopy is a unique label-free imaging modality that provides detailed chemical information at each pixel. In minutes, this technique captures a hyperspectral cube that co-registers
Lee J. Richter, Jonathan Downing, Sebastian Engmann, Hyun W. Ro, Andrew A. Herzing, Dean M. DeLongchamp, Subhrangsu Mukherjee, Harald Ade, Maged Addelsamie, Aram Amassian, Yuhang Liu, He Yan
Solution processing via roll-to-roll (R2R) coating promises a low cost, low thermal-budget, sustainable revolution for the production of solar cells. Yet virtually all high performance solution processed research cells have been demonstrated by spin
Femtosecond pulsed laser interferometry has previously been used to measure picometer-level displacements on sub-nanosecond time scales. In this paper, we experimentally examine its achievable displacement resolution, as well as the relationship between
Kai Hao, Lixiang Xu, Philip Nagler, Akshay Singh, Kha Tran, Chandriker K. Dass, Rupert Huber, Tobias Korn, Xiaoqin Li, Galan Moody
The optical properties of semiconducting transition metal dichalcogenides are dominated by both neutral excitons (electron-hole pairs) and charged excitons (trions) that are stable even at room temperature. While trions directly influence charge transport
Rosalinda Gaudio, Jelmer J. Renema, Zili Zhou, Varun Verma, Jeff Shainline, Martin Stevens, Richard Mirin, Sae Woo Nam, Martin P. van Exter, Michiel J. de Dood, Andrea Fiore
We use quantum detector tomography to investigate the detection mechanism in WSi nanowire superconducting single photon detectors (SSPDs). To this purpose, we fabricated a 250 nm wide and 250 nm long WSi nanowire and measured its response to impinging
This work treats diffraction corrections in radiometry for cases of point and extended sources in symmetric three-element systems. It considers diffraction effects for both spectral power and total power in cases of Planckian sources. This improves upon an
Cynthia Brooks, Benjamin Kidder, Michelle Grigas, Daniel Jaffe, Ulf Griesmann, Daniel Wilson, Richard Muller
We have explored a number of lithographic techniques and improvements to produce the resist lines that then define the grating groove edges of silicon immersion gratings. In addition to our lithographic process using contact printing with photomasks, which
Qian Gong, David Content, Margaret Z. Dominguez, Thomas Emmett, Ulf Griesmann, Jeffrey Kruk, Catherine Marx, Bert Pasquale, Thomas Wallace
The slitless spectrometer plays an important role in the WFIRST mission for the survey of emission-line galaxies. This will be an unprecedented very wide field, HST quality 3D survey of emission line galaxies1. The concept of the compound grism as a
We consider the problem of sorting, by size, spherical particles of order 100 nm radius. The scheme we analyze consists of a heterogeneous stream of spherical particles flowing at an oblique angle across a Gaussian mode optical standing wave. Sorting is