{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,22]],"date-time":"2025-10-22T05:22:31Z","timestamp":1761110551097,"version":"build-2065373602"},"reference-count":30,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2020,10,9]],"date-time":"2020-10-09T00:00:00Z","timestamp":1602201600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The Pencil Beam Scanning (PBS) technique in proton therapy uses fast magnets to scan the tumor volume rapidly. Changing the proton energy allows changing to layers in the third dimension, hence scanning the same volume several times. The PBS approach permits adapting the speed and\/or current to modulate the delivered dose. We built a simple prototype that measures the dose distribution in a single step. The active detection material consists of a single layer of scintillating fibers (i.e., 1D) with an active length of 100 mm, a width of 18.25 mm, and an insignificant space (20 \u03bcm) between them. A commercial CMOS-based camera detects the scintillation light. Short exposure times allow running the camera at high frame rates, thus, monitoring the beam motion. A simple image processing method extracts the dose information from each fiber of the array. The prototype would allow scaling the concept to multiple layers read out by the same camera, such that the costs do not scale with the dimensions of the fiber array. Presented here are the characteristics of the prototype, studied under two modalities: spatial resolution, linearity, and energy dependence, characterized at the Center for Proton Therapy (Paul Scherrer Institute); the dose rate response, measured at an electron accelerator (Swiss Federal Institute of Metrology).<\/jats:p>","DOI":"10.3390\/s20205727","type":"journal-article","created":{"date-parts":[[2020,10,9]],"date-time":"2020-10-09T10:19:23Z","timestamp":1602238763000},"page":"5727","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Characterization of a Low-Cost Plastic Fiber Array Detector for Proton Beam Dosimetry"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4133-2688","authenticated-orcid":false,"given":"Cigdem","family":"Ozkan Loch","sequence":"first","affiliation":[{"name":"Department of Large Scale Research Facilities, Paul Scherrer Institut, 5232 Villigen, Switzerland"}]},{"given":"Michael Alexander","family":"Eichenberger","sequence":"additional","affiliation":[{"name":"Department of Large Scale Research Facilities, Paul Scherrer Institut, 5232 Villigen, Switzerland"}]},{"given":"Michele","family":"Togno","sequence":"additional","affiliation":[{"name":"Center for Proton Therapy, Paul Scherrer Institut, 5232 Villigen, Switzerland"}]},{"given":"Simon Pascal","family":"Zinsli","sequence":"additional","affiliation":[{"name":"Department of Large Scale Research Facilities, Paul Scherrer Institut, 5232 Villigen, Switzerland"}]},{"given":"Martina","family":"Egloff","sequence":"additional","affiliation":[{"name":"Center for Proton Therapy, Paul Scherrer Institut, 5232 Villigen, Switzerland"}]},{"given":"Angela","family":"Papa","sequence":"additional","affiliation":[{"name":"Department for Research with Neutrons and Muons, Paul Scherrer Institut, 5232 Villigen, Switzerland"}]},{"given":"Rasmus","family":"Ischebeck","sequence":"additional","affiliation":[{"name":"Department of Large Scale Research Facilities, Paul Scherrer Institut, 5232 Villigen, Switzerland"}]},{"given":"Antony John","family":"Lomax","sequence":"additional","affiliation":[{"name":"Center for Proton Therapy, Paul Scherrer Institut, 5232 Villigen, Switzerland"}]},{"given":"Peter","family":"Peier","sequence":"additional","affiliation":[{"name":"Laboratory Ionising Radiation, Federal Institute of Metrology (METAS), 3003 Bern-Wabern, Switzerland"}]},{"given":"Sairos","family":"Safai","sequence":"additional","affiliation":[{"name":"Center for Proton Therapy, Paul Scherrer Institut, 5232 Villigen, Switzerland"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1118\/1.597522","article-title":"The 200 MeV proton therapy project at the Paul Scherrer Institute: Conceptual design and practical realization","volume":"22","author":"Pedroni","year":"1995","journal-title":"Med. 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