Sensors 2018, 18(1), 190; https://doi.org/10.3390/s18010190
A Portable Dynamic Laser Speckle System for Sensing Long-Term Changes Caused by Treatments in Painting Conservation
Alberto J. Pérez 1, Rolando J. González-Peña 2,*
, Roberto Braga Jr. 3, Ángel Perles 1,4, Eva Pérez–Marín 5 and Fernando J. García-Diego 6
, Roberto Braga Jr. 3, Ángel Perles 1,4, Eva Pérez–Marín 5 and Fernando J. García-Diego 61
Dep. d’Informàtica de Sistemes i Computadors (DISCA), Universitat Politècnica de València, 46022 Valencia, Spain
2
Dep. Fisiología. Unidad de Biofísica y Física Médica. Facultad de Medicina y Odontología, Universitat de València, 46010 Valencia, Spain
3
Dep. Engenharia (DEG), Universidade Federal de Lavras (UFLA), 3037 Lavras, Brazil
4
ITACA Institute, Camino de Vera, s/n, 46022 Valencia, Spain
5
Dep. de Conservación y Restauración de Bienes Culturales, Universitat Politècnica de València, 46022 Valencia, Spain
6
Dep. de Física Aplicada, Universitat Politècnica de València, 46022 Valencia, Spain
*
Author to whom correspondence should be addressed.
Received: 15 November 2017 / Revised: 5 January 2018 / Accepted: 9 January 2018 / Published: 11 January 2018
(This article belongs to the Special Issue State-of-the-Art Sensors Technology in Spain 2017)
Abstract
Dynamic laser speckle (DLS) is used as a reliable sensor of activity for all types of materials. Traditional applications are based on high-rate captures (usually greater than 10 frames-per-second, fps). Even for drying processes in conservation treatments, where there is a high level of activity in the first moments after the application and slower activity after some minutes or hours, the process is based on the acquisition of images at a time rate that is the same in moments of high and low activity. In this work, we present an alternative approach to track the drying process of protective layers and other painting conservation processes that take a long time to reduce their levels of activity. We illuminate, using three different wavelength lasers, a temporary protector (cyclododecane) and a varnish, and monitor them using a low fps rate during long-term drying. The results are compared to the traditional method. This work also presents a monitoring method that uses portable equipment. The results present the feasibility of using the portable device and show the improved sensitivity of the dynamic laser speckle when sensing the long-term process for drying cyclododecane and varnish in conservation. View Full-Text
Graphical abstract
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MDPI and ACS Style
Pérez, A.J.; González-Peña, R.J.; Braga Jr., R.; Perles, Á.; Pérez–Marín, E.; García-Diego, F.J. A Portable Dynamic Laser Speckle System for Sensing Long-Term Changes Caused by Treatments in Painting Conservation. Sensors 2018, 18, 190.
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