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Purpose: A dosimetric system formed by Gafchromic EBT2 radiochromic film and Epson Expression 10000XL flatbed scanner was commissioned for dosimetry. In this paper, several open questions concerning the commissioning of radiochromic films…

Medical Physics · Physics 2014-03-18 I. Mendez , V. Hartman , R. Hudej , A. Strojnik , B. Casar

Purpose : To relate the physical transmittance parameters of the water equivalent Gafchromic EBT 2 Film with the delivered dose in a transparent absolute calibration protocol. The protocol should be easy to understand, easy to perform, and…

Medical Physics · Physics 2011-07-20 Wouter Crijns , Frederik Maes , Frank Van den Heuvel

We describe a method aiming at increasing the dynamic range of X-ray detectors. Two X-ray exposures of an object are acquired at different dose levels and constitute the only input data. The values of the parameters which are needed to…

Medical Physics · Physics 2007-05-23 Evangelos Matsinos , Wolfgang Kaissl

The main objective of multichannel radiochromic film dosimetry methods is to correct, or at least mitigate, spatial heterogeneities in the film-scanner response, especially variations in the active layer thickness. To this end, films can…

Medical Physics · Physics 2018-09-20 I. Méndez , A. Polšak , R. Hudej , B. Casar

Purpose: The purpose of this work is to develop a new approach for high spatial resolution dosimetry based on Raman micro-spectroscopy scanning of radiochromic film (RCF). We generate dose calibration curves over an extended dose range from…

Medical Physics · Physics 2021-09-15 Connor Mcnairn , Iymad Mansour , Bryan Muir , Rowan M. Thomson , Sangeeta Murugkar

High-dynamic range imaging permits to extend the dynamic range of intensity values to get close to what the human eye is able to perceive. Although there has been a huge progress in the digital camera sensor range capacity, the need of…

Computer Vision and Pattern Recognition · Computer Science 2019-05-21 Jennifer Bonnard , Gilles Valette , Céline Loscos

Methods of increasing linear optical dynamic range of commercial photocamera for optical-digital imaging systems are described. Use of such methods allows to use commercial photocameras for optical measurements. Experimental results are…

Computer Vision and Pattern Recognition · Computer Science 2008-05-20 M. V. Konnik , E. A. Manykin , S. N. Starikov

We present an analytical description and an experimental realization of interscale mixing microscopy, a diffraction-based imaging technique that is capable of detecting wavelength/10 objects in far-field measurements with both coherent and…

In this work, we propose using camera arrays coupled with coherent illumination as an effective method of improving spatial resolution in long distance images by a factor of ten and beyond. Recent advances in ptychography have demonstrated…

Computer Vision and Pattern Recognition · Computer Science 2015-11-29 Jason Holloway , M. Salman Asif , Manoj Kumar Sharma , Nathan Matsuda , Roarke Horstmeyer , Oliver Cossairt , Ashok Veeraraghavan

Pixel size in cameras and other refractive imaging devices is typically limited by the free-space diffraction. However, a vast majority of semiconductor-based detectors are based on materials with substantially high refractive index. We…

Optics · Physics 2018-03-28 Bo Fan , Sandeep Inampudi , Viktor A. Podolskiy

Gigahertz (GHz) imaging using hard X-rays ($\gtrsim$ 10 keV) can be useful to high-temperature plasma experiments, as well as research using coherent photons from synchrotron radiation and X-ray free electron lasers. GHz framing rate can be…

Instrumentation and Detectors · Physics 2023-08-22 Zhehui Wang , C. L. Morris , J. S. Kapustinsky , K. Kwiatkowski , S. -N. Luo

Chromatic aberration in optical systems arises from the wavelength dependence of a glass's refractive index. Polychromatic rays incident upon an optical surface are refracted at slightly different angles and in traversing an optical system…

Many adaptive optics systems operate by measuring the distortion of the wavefront in one wavelength range and performing the scientific observations in a second, different wavelength range. One common technique is to measure wavefront…

Astrophysics · Physics 2009-11-07 Henry G. Roe

Refractive index is a fundamental optical property of powder and a key input to the measurement of the size distribution using light scattering and the measurement of the absorption and scattering coefficients using diffuse reflectance…

Optics · Physics 2024-03-05 Cory Juntunen , Adam J. Rish , Carl Anderson , Yongjin Sung

Coherent diffractive imaging (CDI) provides new opportunities for high resolution X-ray imaging with simultaneous amplitude and phase contrast. Extensions to CDI broaden the scope of the technique for use in a wide variety of experimental…

Optics · Physics 2016-01-20 Matthew H. Seaberg , Alexandre d'Aspremont , Joshua J. Turner

Combined frequency-resolved techniques are suitable to study electrochromic (EC) materials. We present an experimental setup for simultaneous electrochemical and color impedance studies of EC systems in transmission mode and estimate its…

Applied Physics · Physics 2020-01-22 Edgar A. Rojas-González , Gunnar A. Niklasson

Combinations of spectroscopic analysis and microscopic techniques are used across many disciplines of scientific research, including material science, chemistry and biology. X-ray spectromicroscopy, in particular, is a powerful tool used…

Medical Physics · Physics 2023-10-17 Oliver Townsend , Silvia Gazzola , Sergey Dolgov , Paul Quinn

We proposed a novel approach to coherent imaging of dynamic samples. The inter-frame similarity of the sample's local structures is found to be a powerful constraint in phasing a sequence of diffraction patterns. We devised a new image…

Optics · Physics 2024-07-11 Pengju Sheng , Fucai Zhang

In recent years, consumer-level depth cameras have been adopted for various applications. However, they often produce depth maps at only a moderately high frame rate (approximately 30 frames per second), preventing them from being used for…

Graphics · Computer Science 2018-11-06 Ming-Ze Yuan , Lin Gao , Hongbo Fu , Shihong Xia

In the process of parametric optical image amplification, images are formed at new frequencies in addition to the amplified original image. We show that the parametric multiplexing of optical images can be used to produce an image with…

Quantum Physics · Physics 2019-03-27 D. A. Balakin , A. S. Chirkin
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