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Here we describe the implementation and calibration of a streaked visible spectrometer (SVS) for optical pyrometry and emission/absorption spectroscopy on light gas gun platforms in the UC Davis Shock Compression Laboratory. The diagnostic consists of an optical streak camera coupled to a spectrometer to provide temporally and spectrally-resolved records of visible emission from dynamically-compressed materials. Fiber optic coupling to the sample enables a small diagnostic footprint on the target face and flexibility of operation on multiple launch systems without the need for open optics. We present the details of calibration (time, wavelength and spectral radiance) for absolute temperature determination and present benchmark measurements of system performance. [ABSTRACT FROM AUTHOR]

In order to unveil the mystery of ultra high energy cosmic rays (UHECR's), JEM-EUSO (Extreme Universe Space Observatory on-board Japan Experiment Module) will observe extensive air showers induced by UHECR's from the International Space Station orbit with huge acceptance from 2016. Calibration of the JEM-EUSO instrument, which consists of Fresnel optics and 0.3M channel focal surface detector, is very important to discuss the origin of UHECR's precisely with the observed results. In this paper, the calibration system before launch and on-orbit will be reported: the calibration before flight with integrating spheres, on-board calibration light source, and ground light source for on-orbit calibration from ground. [ABSTRACT FROM AUTHOR]

In this work is developed a three-dimensional reconstruction system using the Shades3D tool of the Matlab® Programming Language and materials of low cost, such as webcam camera, a stick, a weak structured lighting system composed by a desk lamp, and observation plane in which the object is located. The reconstruction is obtained through a triangulation process that is executed after acquiring a sequence of images of the scene with a shadow projected on the object; additionally an image filtering process is done for obtaining only the part of the scene that will be reconstructed. Previously, it is necessary to develop a calibration process for determining the internal camera geometric and optical characteristics (intrinsic parameters), and the 3D position and orientation of the camera frame relative to a certain world coordinate system (extrinsic parameters). The lamp and the stick are used to produce a shadow which scans the object; in this technique, it is not necessary to know the position of the light source, instead the triangulation is obtained using shadow plane produced by intersection between the stick and the illumination pattern. The webcam camera captures all images with the shadow scanning the object, and Shades3D tool processes all information taking into account captured images and calibration parameters. Likewise, this technique is evaluated in the reconstruction of parts of the human body and its application in the detection of external abnormalities and elaboration of prosthesis or implant. [ABSTRACT FROM AUTHOR]

A good and complete calibration is the most important step in the electrically addressed spatial light modulator (SLM) initialization. It is clear that the quality and effectiveness of the optical component addressed to the SLM strongly depends on the knowledge of the device response. In fact, the signal must be modified before addressing it to the SLM to compensate for the distortions internally introduced by the device and hence, to eventually reproduce the optical component with the desired performance. In this work we deal with the spatial calibration of reflective zero-twist liquid-crystal on silicon (LCoS) SLM by testing the aperture of the device to characterize the inherent phase distortion. The inherent distortion of the reflective LCoS SLM may need not only the compensation for the backplane curvature but also for other possible non-uniformities caused by thickness variations of the liquid crystal layer across the aperture. Firstly, we build a global Look-Up Table (LUT) of phase modulation versus the addressed grey level for the whole device aperture. Secondly, when a lack of spatial uniformity is observed, we define a grid of cells onto the SLM aperture and develop a multipoint calibration. The relative phase variations between neighbour cells for a uniform grey level lead us to build a multi-LUT for an improved compensation. Multipoint calibration can be done using either phase-shift interferometry or Fourier diffraction pattern analysis of binary phase gratings. Experimental results that give evidence of the compensation progress are provided. We discuss the results obtained when the SLM is used to display diffractive optical elements, with and without compensation of inherent wavefront distortion, and either with global LUT or with multi-LUT. [ABSTRACT FROM AUTHOR]

3D displacement fields are measured by the combination of two optical methods, fringe projection and speckle photography. The use of only one camera recording the necessary information implies that no calibration procedures are necessary as is the case in techniques based on stereoscopy. The out-of-plane displacement is measured by fringe projection whereas speckle photography yields the 2-D in-plane component. To show the feasibility of the technique, we analyze a detailed morphological spatio-temporal evolution of a model of the Earth's crust while subjected to compression forces. The results show that the combination of fringe projection and speckle photography is well suited for this type of studies. [ABSTRACT FROM AUTHOR]

The detailed design of the Impurity Influx Monitor (divertor) has been carried out to provide the measurement capability in the harsh environment such as higher irradiation levels of neutron, gamma-ray and particles than in present devices. The in-situ calibration system using a micro retro-reflector array has been developed to monitor the sensitivity change of the optical system due to the environmental effects. The optical alignment system for the Monitor has been developed by using a dedicated optics for alignment in the collection optics for measurement. [ABSTRACT FROM AUTHOR]

The objectives of this project is to design and install at the SOLEIL synchrotron radiation source a calibration and metrology test facility for the R&D of optical components and detectors. We propose to build, on a bending magnet, three branches dedicated to VUV, soft x-ray and hard x-ray energy ranges. The beamline will cover an energy range from few eV to 28 keV and give access to white beam from the bending magnet. This installation will first address the needs of the SOLEIL experimental groups (Optics and Detectors) and will be used by a large community. This beamline will also be valuable as a general-purpose beamline to prepare, test and set up a wide range of experiments in the field of Astrophysics, laser plasma etc. A complementary important aspect of this installation is the realization of primary standard: the metrology beamline of SOLEIL could become the national primary standard source in collaboration with the Laboratoire National d’Essais (LNE) and help in the design and characterization of several diagnostics for the Megajoule Laser in Bordeaux in collaboration with the CEA DIF. The beamline has been designed to provide great flexibility. In this paper, we describe the beamline design, capabilities, and end station instrumentation. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

A new ultraprecision profiler has been developed to measure for example asymmetric and aspheric profiles. The principle of our measuring method is that the normal vector at each point on the surface is determined by making the incident light beam on the mirror surface and the reflected beam at that point coincident. The gradient at each point is calculated from the normal vector, and the surface profile is then obtained by integrating the gradients. The measuring instrument was designed in accordance with the above principle for the measuring method and is called Surface Gradient Integrated Profiler (SGIP). In the design, four ultraprecision goniometers were applied to adjust the light axis for the normal vector measurement. These goniostages make it possible to attain an angular resolution of 0.018 μ radian by electrically dividing a pulse of the rotary encoder. The surface gradients are determined only by the rotational angle of goniometers. Thus in the measuring instrument, the most important factor is the accuracy of the normal vectors measured by the goniometers. To attain an accuracy of 0.1 μ radian, we developed a system for correcting the rotational angle error of the goniometers in which the trigonometric measuring method is utilized for geometrical angle determination. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]