Last edited by Viramar
Saturday, August 1, 2020 | History

2 edition of Portal imaging with amorphous selenium found in the catalog.

Portal imaging with amorphous selenium

Dennis W. Mah

# Portal imaging with amorphous selenium

## by Dennis W. Mah

Written in English

Edition Notes

The Physical Object ID Numbers Statement by Dennis Mah. Series Canadian theses = Thèses canadiennes Pagination 174 leaves. Number of Pages 174 Open Library OL18552774M ISBN 10 0612276880

Direct conversion imagers utilize photoconductors, such as amorphous selenium (a-Se), to capture and convert incident x-ray photons directly into electric charge. X-ray photons incident upon a layer of a-Se generate electron-hole pairs via the internal photoelectric effect. Amorphous Selenium Direct Radiography for Industrial Imaging Peter K. Soltani, Daniel Wysnewski, Liberty Technologies, Inc., Conshohocken, PA, USA; Ken Swartz, Direct Radiography Corporation, Newark, DE, USA I. Introduction Filmless radiation imaging tools have been available for many years, primarily.

X-ray imaging with amorphous selenium: Theoretical feasibility of the liquid crystal light valve for radiography Rieppo, Pia-Krista; Rowlands, J. A. Abstract. Publication: Medical Physics. Pub Date: August DOI: / Bibcode: MedPhR full text sources. W. Zhao and J.A. Rowlands, "X-ray imaging using amorphous selenium: Feasibility of a flat panel self-scanned detector for digital radiology", Med. Phys, (). doi/; Conference Proceedings.

Amorphous selenium (a-Se), in the form of thermally deposited thin films, is the only x-ray photoconductor that has been successfully developed for making large area medical image sensors. It’s also the only amorphous material that has avalanche multiplication gain.   Investigation of Hole-Blocking Contacts for High-Conversion-Gain Amorphous Selenium Detectors for X-Ray Imaging Abstract: In this paper, we investigated different organic and inorganic hole-blocking contacts for amorphous selenium (a-Se)-based photodetectors: $\hbox{CeO}_{2}$, $\hbox{TiO}_{2}$, perylene tetracarboxylic bisbenzimidazole (PTCBI.

You might also like
scrambler

scrambler

Frog embryo teratogenesis assay Xenopus (FETAX) for soil toxicity screening

Frog embryo teratogenesis assay Xenopus (FETAX) for soil toxicity screening

A report on export potential of Maharashtra

A report on export potential of Maharashtra

Waiving certain points of order against H.R. 4649

Waiving certain points of order against H.R. 4649

Practical solutions in drinking water supply and wastes disposal for developing countries.

Practical solutions in drinking water supply and wastes disposal for developing countries.

Seven sonnets on Puerto Rico

Seven sonnets on Puerto Rico

calculation of neutron cross-sections for the elements hydrogen, carbon, nitrogen and oxygen in the energy range 20-50 MeV.

calculation of neutron cross-sections for the elements hydrogen, carbon, nitrogen and oxygen in the energy range 20-50 MeV.

study on the imitations of Gīta Govinda

study on the imitations of Gīta Govinda

The food stamp application process

The food stamp application process

Ophthalmology in medicine

Ophthalmology in medicine

Fees of Clerks of U.S. Courts, etc.

Fees of Clerks of U.S. Courts, etc.

Bach flower essences and Chinese medicine

Bach flower essences and Chinese medicine

Cupboard Door (Poetry Series)

Cupboard Door (Poetry Series)

### Portal imaging with amorphous selenium by Dennis W. Mah Download PDF EPUB FB2

A flat-panel imager that is expected to achieve these goals is under development. It consists of a thin layer of amorphous selenium that converts x rays directly to an electric charge and a thin-film electronic circuit, or active matrix, to read out the electronic signal directly to a computer host.

The advantages of amorphous selenium include high resolution and low noise without loss of Cited by: Salman M.

Arnab, M. Kabir, Impact of Lubberts Effect on Amorphous Selenium Indirect Conversion Avalanche Detector for Medical X-Ray Imaging, IEEE Transactions on Radiation and Plasma Medical Sciences, /TRPMS, 1, 3, (), ().Cited by:   In this paper, the authors propose a mechanically flexible direct conversion x-ray detector as a potential solution for portable and conformal digital x-ray imaging.

It consists of a micropillar structured layer of μm-thick amorphous selenium (a-Se) on a flexible thin film transistor (TFT) backplane with a pixel size of 70 μm as a substrate.

The flexible substrate is Cited by:   Our work is to investigate and understand the factors affecting the imaging performance of amorphous selenium flat‐panel detectors for digital mammography. Both theoretical and experimental methods were developed to investigate the spatial frequency dependent detective quantum efficiency of a‐Se flat‐panel detectors for digital mammography.

Cited by: imaging. The proposed detector is based on amorphous selenium (a-Se). Amorphous selenium is the most highly developed photoconductor for large area direct conversion X-ray imaging and is still the only commercially available large area direct conversion flat panel X-ray detector.

However, the use of a-Se for indirect conversion imaging has not. It is used in its amorphous form, so amorphous selenium plates can be made by evaporation. Thus, in contrast to many crystalline photoconductors, a-Se based detectors can be made large in area relatively easily and inexpensively.

The electric properties, namely the low dark or leakage current, of a-Se also render it suitable for X-ray imaging use. Imaging performance of an amorphous selenium digital mammography detector in a breast tomosynthesis system Bo Zhao a) and Wei Zhao Department of Radiology, State University of New York at Stony Brook, L-4 Health Science Center, Stony Brook, New York Electronic portal imaging devices (EPIDs) are used to measure the x-ray intensity transmitted through a patient from a radiation port during a treatment session.

The radiation signal is converted electronically into a two-dimensional (2D) digital radiographic image to verify the correct beam placement in relation to the patient’s anatomy.

Yuan Fang, E.O. Bryan, S. Hasibul Majid, R.J. Jennings‘ Pulse-Height Spectroscopy of Amorphous Selenium Detectors for X-ray Imaging Application ’, IEEE Symposium on Radiation Measurements and Applications x-ray interact directly with a radiation-conversion material made of amorphous selenium(a-Se) the photoconductor absorbs the x-rays and convert into electrons that are stored in TFT.

then sequentially read and sent to the ADC and then to the computer to reconstruction. Amorphous-selenium (a-Se) based photodetectors are promising candidates for imaging devices, due to their high spatial resolution and response speed, as well as extremely high sensitivity enhanced by an internal carrier multiplication.

In addition, a-Se is reported to show sensitivity against wide variety of wavelengths, including visible, UV and X-ray, where a-Se. Zhao W, Rowlands JA () X-ray imaging using amorphous selenium: Feasibility of a flat panel self-scanned detector for digital radiology, Medical Physics – CrossRef PubMed Google Scholar.

This book focuses on their imaging applications and related properties. It examines the two groups of amorphous semiconductors that are of most commercial interest: the chalcogenide glasses; the tetrahedrally bonded amorphous solids such as amorphous silicon, germanium and related alloys.

Our code is used to propagate a simulated x-ray fluence through each component of an existing video-based portal imaging system.

book on scientific computing. based on amorphous selenium. The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. Investigation of Hole-Blocking Contacts for High-Conversion-Gain Amorphous Selenium Detectors for X-Ray Imaging Abbaszadeh, S., Allec, N., we investigated different organic and inorganic hole-blocking contacts for amorphous selenium (a-Se.

Imaging performance of amorphous selenium based flat-panel detectors for digital mammography: characterization of a small area prototype detector.

Med Phys ; – Rowlands, JA, Hunter, DM, Araj, N. Amorphous selenium (a-Se) based direct conversion flat-panel imagers (FPI) have been widely used in DM and DBT imaging systems. The a-Se layer is typically μm thick with quantum detective efficiency (QDE) >87% for x-ray energies below 26 keV.

However, QDE decreases substantially above this energy. Amorphous chalcogenide semiconductors have commercial value and have many uses such as image formation, including x-rays, and high-definition TV pick up tubes. This book focuses on their imaging applications and related properties.

It provides information on the amorphous semiconductors that are of most commercial interest. In addition to the physical principles of imaging techniques, the book also familiarizes you with the equipment and procedures used in diagnostic imaging.

Show less Medical Imaging Technology reveals the physical and materials principles of medical imaging and image processing, from how images are obtained to how they are used. Rowlands J A and Hunter D MX-ray imaging using amorphous selenium: Generalised analysis of Photo-induced discharge (PID) readout methods Med.

Phys. 22 Crossref PubMed Google Scholar Rowlands J A, Hunter D M and Araj N X-ray imaging using amorphous selenium: A photoinduced readout method for digital mammography Med. Amorphous selenium direct detection CMOS digital x-ray imager with 25 micron pixel pitch.

In Medical Imaging Physics of Medical Imaging [G] (Progress in Biomedical Optics and Imaging - Proceedings of SPIE; Vol. ). SPIE.Mature amorphous selenium technology and recent progress on high-quality Thin-Film Transistor (TFT) arrays for computer displays have allowed development of practical large-area high-resolution flat-panel x-ray imaging systems.resolution selenium-based imaging system has been measured at megavoltage energies.

These results have been compared with theoretical calculations. The imaging system was a video tube with a 5 m amorphous selenium (a-Se) target which was irradiated by MeVγ-rays. The.