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THE medical imaging technologies and the industrial ones have benefitted from each other. For a baggage inspection for example, multiple-detector helical CT scanning technology has been deployed that was originally developed for a fast volumetric imaging of a patient in clinics. In a helical CT, the detector array and the x-ray source are rotating continuously in a gantry with the slip-ring technology,...
This works shows the feasibility study performed with a new small animal PET design based on SiPM arrays in front of a high field MR scanner. The PET ring is made out of 8 detector blocks each containing a single monolithic 50×50×10 mm3 LYSO block and coupled to an array of 12×12 SiPMs. The PET system performance has been evaluated both alone and in front of the MR with about 400–500 mT magnetic field...
The use of monolithic crystals to detect the incident gamma photons for PET imaging has the flexibility to virtually define the detector pixel size. These pixels determine the Lines Of Response (LORs) needed during the reconstruction process. Although there are very few groups using monolithic crystals for PET, the most common approach is to homogeneously define the dimensions for the virtual pixels...
A new design of the small animal PET Albira system which detectors are based on arrays of SiPMs and monolithic LYSO scintillator is presented here. The system is made out of 3 rings of 8 detectors each, resulting on an axial and transaxial FOVs of 148 and 80 mm, respectively. The scanner is thermally stabilized using air-cooling. Working temperatures around 22–25°C are reached with individual detector...
The KLOE-2 Inner Tracker, the first fully-cylindrical GEM detector ever built, is being commissioned at the Frascati Laboratory of INFN. KLOE-2 is the first experiment exploiting GEM technology with cylindrical geometry. Tracking performance of this novel detector are being studied using both cosmic-ray muon and Bhabha scattering events. Alignment and calibration procedures to reach design spatial...
The finite focal spot size is one of the major physical limitations to the spatial resolution for CT reconstruction. In this paper, a projection restoration based method is proposed to improve the spatial resolution. First of all, the focal spot size is considered into the projection model. Then the equivalence relation between the measured projection and the ideal projection is deduced. Based on...
A resonance neutron imaging system has been developed based on combination of a glass based Gas Electron Multiplier (Glass GEM) detector and a resonance filter. This system has the capability of imaging the neutron spatial distribution in energy of resonance peaks corresponding to a resonance filter. A clear dip corresponding to a resonance peak of 109Ag (4.2∼6.3 eV) was confirmed in measured response...
In the ATLAS Muon Spectrometer, Monitored Drift Tube (MDT) chambers and sMDT chambers with half of the tube diameter of the MDTs are used for precision muon track reconstruction. The sMDT chambers are designed for operation at high counting rates due to neutron and gamma background irradiation expected for the HL-LHC and future hadron colliders. The existing MDT read-out electronics uses bipolar signal...
In this paper, we apply the pixel imaging to generate images for catching picture information. Pixel imaging technique has great advantages over the array imaging in the cost area. It has been found out that multi-spectral imaging with high resolution can be acquired when compared with traditional methods. In the part of dynamic imaging, some technical issues are discussed for the use of the pixel...
The wave scattered by the longitudinal component of a tightly focused radially polarized beam is clearly detected in a confocal system, which may lead to the enhancement of the spatial resolution in confocal microscopy.
We present a technique to drive high-order harmonics with angularly spatially chirped pulses. Our calculations show that each harmonic is emitted with angular chirp, leading to dramatically improved control of spectral and temporal spatial resolution.
Anomaly detection have been studied over few decades and successful results have been given in the literature. Local and global anomaly detection schemes are usually used separately and their strong points are not used perfectly. In this paper, we propose a new method both using local and global anomaly methods. Additionally, we propose a new modified local anomaly technique in between the dual-window...
During acquisition, digital images are invariably degraded by a number of phenomena that limit image resolution and utility. Aliasing from undersampling, blur from optics, and sensor noise are some factors which can affect the image resolution. Multi-frame super-resolution (SR) is a technique that takes several low-resolution (LR) frames of a particular scene and processes them together to produce...
Imaging techniques for domain analysis are still one of the most important means of investigation in magnetic materials field [1]. In this work, we develop a new approach to perform magneto-optical imaging, applying for the first time a high resolution Ghost Imaging (GI) protocol to perform Faraday microscopy, and thus to reconstruct the image of Weiss domains within a magnetic sample.
Corner detection is a important task in low level vision. Detecting corners helps one to establish similarity between two or more images. Traditional approaches for corner detection involve finding significant variation around a pixel neighbourhood in two different directions. In this work, we have developed a novel framework to detect corners in a given image by learning corners from images corresponding...
The Multimodal Imaging of Neurological Disorders (MINDview) project aims to develop a high resolution and sensitivity dedicated brain Positron Emission Tomography (PET) system capable of visualizing neurotransmitter pathways and their disruptions for mental disorders for diagnosis and treatment follow-up. Moreover, this compact PET system should be fully compatible with a Magnetic Resonance Imaging...
A spatially variant resolution modelling technique for PET image reconstruction is presented which models the physical processes of the measurement during the iterative reconstruction. This is achieved by redistributing the line-of-response endpoints according to derived probability density functions describing the detector response function and photon acollinearity. When applying this technique it...
Edge illumination (EI) X-ray phase-contrast imaging has great potential for applications in a wide range of research, industrial and clinical fields. The optimization of the EI experimental setup for a given application is therefore essential, in order to take full advantage of the capabilities of the technique. In this work, we analyze the dependence of the angular sensitivity, spatial resolution...
The feedback of positive ions in gas amplification detectors of a time projection chamber (TPC) causes adverse effects on the electric field in the drift region, thereby degrading the spatial resolution of the TPC. Instead of employing a conventional wire-grid as a gating device, as often done to alleviate this problem, there is a proposed solution to use a gas electron multiplier (GEM) operated in...
For the High-Luminosity LHC (HL-LHC) phase the CMS GEM Collaboration is planning to install new large-size (990×220–455mm2) triple-GEM detectors, equipped with a new readout system, in the forward region of the muon system (1.5< |η| <2.2) of the CMS detector. Combining triggering and tracking functionalities the new triple-foil Gas Electron Multiplier (GEM) chambers will improve both the performance...
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