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Figure 3 shows the [[scattering]] of HeNe [[laser]] light from noise gratings recorded in [[Poly(methyl methacrylate)|PMMA]] using a 325 nm HeCd laser.
One of the early results from the project was in developing a repeatable method for joining polymer fiber to standard silica fiber — a major development that enabled using POF Bragg gratings in applications outside an optics lab. One of the first uses for these sensors was in monitoring strain in tapestries<ref>http://eprints.soton.ac.uk/68650/01/137_Lennard.pdf {{Bare URL PDF|date=March 2022}}</ref> shown in Figure 4,.<ref>{{Cite web|url=http://spie.org/x39927.xml?ArticleID=x39927|title = Polymer-fiber grating sensors}}</ref> In this case conventional electrical strain sensors and silica fiber sensors were shown to be strengthening the tapestries in areas where they were fixed. Because polymer fibre devices are much more flexible they did not distort the textiles as much, permitting more accurate measurement of strain.
Temperature and humidity sensing using a combined silica / POF fiber sensor has been demonstrated.<ref>Optical fibre temperature and humidity sensor, C. Zhang, W. Zhang, D.J. Webb, G.D. Peng, Electronics Letters, 46, 9, pp643-644, 2010, {{doi|10.1049/el.2010.0879}}</ref> Combined strain, temperature and bend sensing has also been shown.<ref>Bragg grating in polymer optical fibre for strain, bend and temperature sensing, X. Chen, C. Zhang, D.J Webb, G.-D. Peng , K. Kalli, Measurement Science and Technology, 2010</ref> Using a fiber Bragg grating in an eccentric core polymer has been shown to yield a high sensitivity to bend.<ref>Highly Sensitive Bend Sensor Based on Bragg Grating in Eccentric Core Polymer Fiber, X. Chen, C. Zhang, D.J. Webb, K. Kalli, G.-D. Peng, A. Argyros, IEEE Sensors Journal, 2010</ref>
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* Silica [[microstructured fiber]]s for temperature-insensitive optical sensors - a new pressure-sensitive and temperature-insensitive optical fibre sensor has been developed. The sensor uses a [[fiber Bragg grating]] written into a [[microstructured fiber]]. The pressure sensitivity exceeds the state-of-the-art with a factor of 20, whilst the sensor is truly temperature-insensitive. The sensor is based on a novel design of a highly birefringent (10<sup>−3</sup>) microstructured optical fibre sensor that is designed to have a high pressure sensitivity (3.3 pm/bar), whilst at the same time exhibit negligible temperature sensitivity (10<sup>−2</sup> pm/K). The fabrication method is compatible with conventional ultraviolet grating inscription setups for [[fiber Bragg grating]] manufacture. The temperature insensitivity was achieved by tailoring the design of the doped region in the core of the [[microstructured fiber]] via a series of design iterations.<ref>{{Cite web |url=http://www.phosfos.eu/eng/Phosfos/Facts-Results/Fact-sheet-01-Silica-Microstructured-Optical-Fibre-Sensor |title=Archived copy |access-date=2011-08-14 |archive-url=https://web.archive.org/web/20111126051342/http://www.phosfos.eu/eng/Phosfos/Facts-Results/Fact-sheet-01-Silica-Microstructured-Optical-Fibre-Sensor |archive-date=2011-11-26 |url-status=dead }}</ref>
* Embedded optoelectronic devices - the possibility to integrate optical sources and photodetectors, compatible with the optical fibre sensors has been developed within the PHOSFOS project. The optoelectronic components are thinned down by polishing until they are only 20 μm thick so that they become flexible themselves without compromising functionality. Thin optical sources and detectors are then embedded in optical clear polymers, and electrically contacted using well-established micro- via, metallization and patterning technologies.<ref>{{Cite web |url=http://www.phosfos.eu/eng/Phosfos/Facts-Results/Fact-Sheet-02-Embedded-Opto-electronic-Chips |title=Archived copy |access-date=2011-08-14 |archive-url=https://web.archive.org/web/20111127063559/http://www.phosfos.eu/eng/Phosfos/Facts-Results/Fact-Sheet-02-Embedded-Opto-electronic-Chips |archive-date=2011-11-27 |url-status=dead }}</ref>
* Integrated sensors and optoelectronics - several different approaches for embedding optical fibre sensors in a flexible and stretchable host material, including injection molding, laser structuring, and soft lithography were considered. The influence of the embedding process was studied for silica and polymer [[fiber Bragg gratings]]. Temperature, humidity, strain, curvature and pressure sensitivities were fully characterized for different flexible host materials. An approach in which the embedded optoelectronic chips can be efficiently coupled towards the optical fiber sensors, using dedicated coupling structures, incorporating a 45˚ micromirror, as well as a fiber alignment groove was proposed. This allowed low cost components to be used in combination with well-established fabrication technologies, to demonstrate a truly low cost fully integrated sensing foil for biomedical applications.<ref>{{Cite web |url=http://www.phosfos.eu/eng/Phosfos/Facts-Results/Fact-Sheet-03-Integrating-Sensors-and-Opto-electronics-in-Flexible-Materials |title=Archived copy |access-date=2011-08-14 |archive-url=https://web.archive.org/web/20111127063605/http://www.phosfos.eu/eng/Phosfos/Facts-Results/Fact-Sheet-03-Integrating-Sensors-and-Opto-electronics-in-Flexible-Materials |archive-date=2011-11-27 |url-status=dead }}</ref>
* Polymer [[fiber Bragg gratings]] - prior to the commencement of PHOSFOS, gratings in polymer optical fibre (POF) only existed in the 1550 nm spectral region where the large fibre loss (1 dB/cm) only permitted very short (<10 cm) fibre lengths to be used and the devices had to be butt-coupled to a silica fiber pigtail on the optical bench.
The PHOSFOS consortium has developed a means for reliably splicing POF to silica fibre and produced the first gratings in the 800 nm spectral region where losses are almost 2 orders of magnitude less than at 1550 nm. These developments have allowed POF grating sensors to be used outside the laboratory for the first time.<ref>{{Cite web |url=http://www.phosfos.eu/eng/Phosfos/Facts-Results/Fact-Sheet-04-Polymer-Fibre-Bragg-Gratings |title=Archived copy |access-date=2011-08-14 |archive-url=https://web.archive.org/web/20111127063610/http://www.phosfos.eu/eng/Phosfos/Facts-Results/Fact-Sheet-04-Polymer-Fibre-Bragg-Gratings |archive-date=2011-11-27 |url-status=dead }}</ref>
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* Polymers for flexible skinlike materials - a series of polymer materials were developed that have inherent flexibility and tuneable mechanical strength. They are also visually transparent and are compatible with commercially available formulations. A great step forward in developing novel monomers and prepolymers that supplement commercial formulations was taken and several novel formulations created. Finally, we also developed a new optical fiber coating material that quickly cures on silica fibres under UV irradiation.<ref>{{Cite web |url=http://www.phosfos.eu/eng/Phosfos/Facts-Results/Fact-Sheet-07-Polymers-for-Flexible-Skinlike-Materials |title=Archived copy |access-date=2011-08-14 |archive-url=https://web.archive.org/web/20111127063625/http://www.phosfos.eu/eng/Phosfos/Facts-Results/Fact-Sheet-07-Polymers-for-Flexible-Skinlike-Materials |archive-date=2011-11-27 |url-status=dead }}</ref>
* Sensing system for silica microstructured fibers for pressure and temperature sensing - the silica MSF based pressure sensor has great potential value potential in the field of downhole pressure monitoring within the oil and gas industry. In this application there is a need to monitor high pressures (range from 0 to 1000 bar) in combination with fast temperature variations. The ultralow temperature cross-sensitivity is therefore an important feature of this system<ref>{{Cite web |url=http://www.phosfos.eu/eng/Phosfos/Facts-Results/Fact-Sheet-08-Silica-Microstructured-Optical-Fibre-Sensor-Pre-Product-Prototype |title=Archived copy |access-date=2011-08-14 |archive-url=https://web.archive.org/web/20111126051446/http://www.phosfos.eu/eng/Phosfos/Facts-Results/Fact-Sheet-08-Silica-Microstructured-Optical-Fibre-Sensor-Pre-Product-Prototype |archive-date=2011-11-26 |url-status=dead }}</ref>
* Sensing system for multimode polymer fiber Bragg gratings - fiber Bragg grating sensors are commonly used for strain and temperature sensing but
pressure sensing can be more challenging especially when space is limited. The PHOSFOS project consortium developed a new polymer multipoint FBG sensor that can measure the pressure in various medical applications. The fact that polymer fiber is used rather than silica fiber is beneficial in terms of patient safely. The low [[Young's modulus]] of polymer fiber improves the strain transfer from the surrounding medium to the sensors.<ref>{{Cite web |url=http://www.phosfos.eu/eng/Phosfos/Facts-Results/Fact-Sheet-09-Polymer-Fibre-Bragg-Grating-Oesophageal-Sensor-Demonstrator |title=Archived copy |access-date=2011-08-14 |archive-url=https://web.archive.org/web/20111127063630/http://www.phosfos.eu/eng/Phosfos/Facts-Results/Fact-Sheet-09-Polymer-Fibre-Bragg-Grating-Oesophageal-Sensor-Demonstrator |archive-date=2011-11-27 |url-status=dead }}</ref><ref>{{Cite web |url=http://www.phosfos.eu/eng/Phosfos/Facts-Results/Fact-Sheet-10-Polymer-Fibre-Bragg-Grating-Interrogator |title=Archived copy |access-date=2011-08-14 |archive-url=https://web.archive.org/web/20111127063635/http://www.phosfos.eu/eng/Phosfos/Facts-Results/Fact-Sheet-10-Polymer-Fibre-Bragg-Grating-Interrogator |archive-date=2011-11-27 |url-status=dead }}</ref>
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