نتایج جستجو برای: pinhole test

تعداد نتایج: 813623  

Journal: :International Journal of Computer Vision 2014

Journal: :Physics in medicine and biology 2010
Marlies C Goorden Freek J Beekman

State-of-the-art small-animal single photon emission computed tomography (SPECT) enables sub-half-mm resolution imaging of radio-labelled molecules. Due to severe photon penetration through pinhole edges, current multi-pinhole SPECT is not suitable for high-resolution imaging of photons with high energies, such as the annihilation photons emitted by positron emitting tracers (511 keV). To deal ...

Journal: :Journal of nuclear medicine : official publication, Society of Nuclear Medicine 2001
F H Fahey K L Grow R L Webber B A Harkness E Bayram P F Hemler

UNLABELLED Emission tuned-aperture computed tomography (ETACT) is a new approach to acquiring and processing scintimammography data. A gamma camera with a pinhole collimator is used to acquire projections of the radionuclide distribution within the breast. Fiducial markers are used to reconstruct these projections into tomographic slices. Simulation and phantom experiments were performed to eva...

2010
Jae-Hyun Jung Keehoon Hong Gilbae Park Indeok Chung Byoungho Lee

Jae-Hyun Jung Keehoon Hong Gilbae Park Indeok Chung Byoungho Lee (SID Member) Abstract — A 360°-viewable cylindrical three-dimensional (3-D) display system based on integral imaging has been implemented. The proposed system is composed of a cylindrically arranged electroluminescent (EL) pinhole film, an EL film backlight, a barrier structure, and a transmission-type flexible display panel. The ...

2008
J. W. Keen

We use a numerical simulation to investigate the effectiveness of pinhole spatial filters at optical/IR interferometers and to compare them with single-mode optical fibre spatial filters and interferometers without spatial filters. We show that fringe visibility measurements in interferometers containing spatial filters are much less affected by changing seeing conditions than equivalent measur...

2016
S. Takano M. Masaki

At the SPring-8 storage ring, we have recently developed two X-ray instruments for emittance diagnostics. The one for a bending magnet source is the X-ray pinhole camera which directly images the beam profile. A pinhole in the atmosphere is composed of combined narrow X-Y slits made of tungsten. A scintillator crystal is used to convert the X-ray beam image to a visible image. The spatial resol...

2013
A. L. KOROTKOV

We report on the design, calibration and in-flight performance of a sun sensor, which is used to determine the attitude of a balloon-borne telescope. The device uses a position-sensitive detector (PSD) in a pinhole camera. By determining the position of the image of the Sun on the PSD, the orientation of the sun sensor and the boresight of the telescope relative to the Sun can be determined. Th...

2016
Xianjun Ye Matthew D McCluskey

In conventional confocal microscopy, a physical pinhole is placed at the image plane prior to the detector to limit the observation volume. In this work, we present a modular design of a scanning confocal microscope which uses a CCD camera to replace the physical pinhole for materials science applications. Experimental scans were performed on a microscope resolution target, a semiconductor chip...

2006
Voicu Popescu

Camera models are essential infrastructure in computer graphics, visualization, and vision. The most frequently used model is the planar pinhole camera, because it approximates the human eye well, producing familiar images, and because it is simple, enabling efficient software and hardware implementations. However, the requirement that all rays pass through a common point is restrictive and rel...

2002
J. K. Viljas E. V. Thuneberg

We theoretically study the dc Josephson effect between two volumes of superfluid He-B. We first discuss how the calculation of the current-phase relationships is divided into mesoscopic and macroscopic problems. We then analyze mass and spin currents and the symmetry of weak links. In quantitative calculations the weak link is assumed to be a pinhole, whose size is small in comparison to the co...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید