skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Medipix2/USB Portable Radiation Camera

Abstract

Advances in the field of semiconductor technologies in the last years make possible to develop new types of ionizing radiation detectors. The Medipix2 readout ASIC is an example of such a device. It is the hybrid single photon counting imaging chip (sensor and readout chips are fabricated separately). With an appropriate sensor chip on the top, it can count single X-ray photons, without any noise or dark current, at high fluxes (several Gigaphotons per cm{sup 2} per second). It also offers excellent radiation hardness and good position resolution (256x256 pixels, each pixel has a 55x55 {mu}m{sup 2} area). To make the Medipix2 imaging chip more portable for specific applications a microprocessor controlled read-out system based on the USB (Universal Serial Bus) interface has been developed. It integrates all necessary detector support into one compact device (75x46 mm{sup 2}). All power supplies including sensor bias (up to 100 V) are internally derived from the voltage provided by the USB connection.

Authors:
; ; ; ;  [1]
  1. Institute of Experimental and Applied Physics, Czech Technical University in Prague Horska 3a/22, CZ-12800 Prague 2 (Czech Republic)
Publication Date:
OSTI Identifier:
21039371
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 958; Journal Issue: 1; Conference: 4. International summer school on nuclear physics methods and accelerators in biology and medicine, Prague (Czech Republic), 8-19 Jul 2007; Other Information: DOI: 10.1063/1.2825757; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; CAMERAS; EQUIPMENT INTERFACES; IMAGES; MICROPROCESSORS; PHOTONS; POWER SUPPLIES; READOUT SYSTEMS; RESOLUTION; SEMICONDUCTOR MATERIALS; SENSORS; SI SEMICONDUCTOR DETECTORS; X RADIATION; X-RAY DETECTION

Citation Formats

Vykydal, Z., Holy, T., Jakubek, J., Platkevic, M., and Pospisil, S. Medipix2/USB Portable Radiation Camera. United States: N. p., 2007. Web. doi:10.1063/1.2825757.
Vykydal, Z., Holy, T., Jakubek, J., Platkevic, M., & Pospisil, S. Medipix2/USB Portable Radiation Camera. United States. doi:10.1063/1.2825757.
Vykydal, Z., Holy, T., Jakubek, J., Platkevic, M., and Pospisil, S. 2007. "Medipix2/USB Portable Radiation Camera". United States. doi:10.1063/1.2825757.
@article{osti_21039371,
title = {Medipix2/USB Portable Radiation Camera},
author = {Vykydal, Z. and Holy, T. and Jakubek, J. and Platkevic, M. and Pospisil, S.},
abstractNote = {Advances in the field of semiconductor technologies in the last years make possible to develop new types of ionizing radiation detectors. The Medipix2 readout ASIC is an example of such a device. It is the hybrid single photon counting imaging chip (sensor and readout chips are fabricated separately). With an appropriate sensor chip on the top, it can count single X-ray photons, without any noise or dark current, at high fluxes (several Gigaphotons per cm{sup 2} per second). It also offers excellent radiation hardness and good position resolution (256x256 pixels, each pixel has a 55x55 {mu}m{sup 2} area). To make the Medipix2 imaging chip more portable for specific applications a microprocessor controlled read-out system based on the USB (Universal Serial Bus) interface has been developed. It integrates all necessary detector support into one compact device (75x46 mm{sup 2}). All power supplies including sensor bias (up to 100 V) are internally derived from the voltage provided by the USB connection.},
doi = {10.1063/1.2825757},
journal = {AIP Conference Proceedings},
number = 1,
volume = 958,
place = {United States},
year = 2007,
month =
}
  • A Medipix2 device was exposed to radioactive sources ({sup 241}Am, {sup 137}Cs and {sup 106}Ru). To test the reliability of track recognition with this device, the activities of the radioactive sources were extracted from the experimental data and compared to the expected activities.
  • The charge sharing effect has been studied with a Medipix2 detector exposed to protons. This effect has been investigated as a function of the bias voltage and incident angle.
  • A need exists for high-speed single-photon counting optical imaging detectors. Single-photon counting high-speed detection of x rays is possible by using Medipix2 with pixelated silicon photodiodes. In this article, we report on a device that exploits the Medipix2 chip for optical imaging. The fabricated device is capable of imaging at >3000 frames/s over a 256x256 pixel matrix. The imaging performance of the detector device via the modulation transfer function is measured, and the presence of ion feedback and its degradation of the imaging properties are discussed.
  • The combination of a mechanically-collimated camera with an electronically-collimated camera offers both the high efficiency and good angular resolution typical in a mechanically-collimated camera for lower energies and the uncoupling of spatial resolution and efficiency provided by an electronically-collimated camera at higher energies. The application is an industrial gamma-ray imaging system with good angular resolution and efficiency over a broad energy range: 50 keV to 3 MeV. The design and performance modeling of the Hybrid Portable Gamma Camera, currently being built, is described here. The optimization of the Angerlogic first detector module in terms of spatial and energy resolution ismore » accomplished using a Monte Carlo optical photon modeling code and Cramer-Rao lower bound calculations. Approximately 6 mm spatial resolution and 7.5% FWHM (statistical contribution only) energy resolution for a 140 keV incident energy are expected for the 100 x 100 x 10 mm{sup 3} NaI(Tl) first detector. Analytical calculations of angular resolution components and efficiency for the Hybrid Portable Gamma Camera are compared to Monte Carlo calculations of the same quantities. The expected angular resolution performance for on-axis point sources, a central scattering angle of 30{degree} and a detector separation distance of 35 cm ranges from 3--5{degree} FWHM over the sensitive energy range. Intrinsic efficiency results over the same energy range are also presented.« less