Optical fibre long-period grating sensors: characteristics and application

James, Stephen W.; Tatam, Ralph P.

doi:10.1088/0957-0233/14/5/201

Cited by 1,142 publications

(717 citation statements)

References 98 publications

Supporting

Mentioning

674

Contrasting

Unclassified

Order By: Relevance

“…This coupling is manifested in the transmission spectrum of the optical fibre as a series of resonance bands. Each resonance band corresponds to coupling to a different cladding mode and thus shows different sensitivity to environmental changes [28]. The coupling wavelength can be obtained from the following phase matching equation…”

Section: Introductionmentioning

confidence: 99%

“…where x represents the wavelength at which light is coupled to the LP 0x cladding mode, n core is the effective refractive index of the mode propagating in the core of the fibre, n clad(x) is the effective index of the LP 0x cladding mode and is the period of the LPG [28]. The central wavelength of the resonance band is sensitive to changes in the surrounding environment such as temperature or external index of refraction [28].…”

Section: Introductionmentioning

confidence: 99%

“…The central wavelength of the resonance band is sensitive to changes in the surrounding environment such as temperature or external index of refraction [28]. It has been shown that the phase matching condition for the higher order cladding modes contains a turning point and that the LPG exhibits the highest sensitivity when phase matching turning point (PMTP) is reached.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Highly sensitive volatile organic compounds vapour measurements using a long period grating optical fibre sensor coated with metal organic framework ZIF-8

Hromádka

Tokay

Correia

et al. 2018

Sensors and Actuators B: Chemical

View full text Add to dashboard Cite

a b s t r a c tAn optical fibre long period grating (LPG) based volatile organic compound (VOC) sensor coated with ZIF-8, a material from the zeolite imidazolate framework (ZIF) family, functional coating is presented. ZIF-8 film was deposited onto the surface of the LPG using an in-situ crystallization technique by mixing freshly prepared 12.5 mM zinc nitrate hexahydrate and 25 mM 2-metyl-imidazole solutions in methanol. A concentration specific response to acetone, ethanol and methanol vapour was obtained over the high concentration range up to tens thousands ppm. The LPG based sensor works at phase-matching turning point (PMTP) and such operates at the highest sensitivity. A novel approach for the data analysis based on the measurement of the bandwidth of the U-shaped attenuation band of the LPG is introduced. The optimized sensor shows a sensitivity of 0.015 ± 0.001 and 0.018 ± 0.0015 nm/ppm and limit of detection (LOD) of 6.67 and 5.56 ppm for acetone and ethanol respectively.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Highly sensitive volatile organic compounds vapour measurements using a long period grating optical fibre sensor coated with metal organic framework ZIF-8

Hromádka

Tokay

Correia

et al. 2018

Sensors and Actuators B: Chemical

View full text Add to dashboard Cite

show abstract

“…For these gratings the energy typically couples from the fundamental guided mode to discrete, forward propagating cladding mode. Each LPG with a given periodicity selectively filters light in a narrow band width centred on the peak wavelength of coupling i [18] …”

Section: Introductionmentioning

confidence: 99%

Metglas thin film based magnetostrictive transducers for use in long period fibre grating sensors

Thomas

Mathew

Radhakrishnan

et al. 2010

Sensors and Actuators A: Physical

View full text Add to dashboard Cite

a b s t r a c tMetallic glass alloy Metglas 2826 MB based amorphous magnetic thin films were fabricated by the thermal evaporation technique. Transmission electron micrographs and electron diffraction pattern showed the amorphous nature of the films. Composition of the films was analyzed employing X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy techniques. The film was integrated to a long period fibre grating. It was observed that the resonance wavelength of the fibre grating decreased with an increase in the magnetic field. Change in the resonance wavelength was minimal at higher magnetic fields. Field dependent magnetostriction values revealed the potential application of these films in magnetostrictive sensor devices.

show abstract

“…The LPFGs have found a variety of applications in optical communications [1,2]. Tuning of the LPFGs is very attractive since it can offer a form of dynamic spectral control [3,4]. The central attenuation wavelength of the LPFGs is highly sensitive to temperature, strain, bend or surrounding refractive index (SRI) changes.…”

mentioning

confidence: 99%

A Novel Electrically Tunable Long-Period Fiber Grating Using a Liquid Crystal Cladding Layer

Czapla

Woliński

Nowinowski-Kruszelnicki

et al. 2010

Acta Phys. Pol. A

View full text Add to dashboard Cite

The main aim of the presented work is the integration of a long-period fiber grating and a liquid crystal into a hybrid structure, in order to develop an innovative fiber optic device controlled by an external electric field. The studied long-period fiber grating was fabricated using UV irradiation in a boron co-doped fiber (PS1250/ 1500, manufactured by Fibercore). As a liquid crystal we used a typical 5CB nematic liquid crystal. The sensing mechanism of the proposed loss filter relies on long-period fiber grating attenuation bands sensitivity to optical properties of the liquid crystal layer. The results obtained show that the long-period fiber grating with a nanosized liquid crystal layer exhibits one order of magnitude higher electrical sensitivity and a lower level of the voltage control than the long-period fiber grating with a micro-sized liquid crystal layer.PACS IntroductionIn order to achieve light coupling between two co--propagating modes, a grating formed in an optical fiber usually requires a pitch of several hundred micrometers. This type of grating is called a long-period fiber grating (LPFG). Compared to other optical devices, LPFGs have a number of unique advantages such as low-level back reflection, low insertion losses and compact construction (the grating is an intrinsic fiber device). The LPFGs have found a variety of applications in optical communications [1,2]. Tuning of the LPFGs is very attractive since it can offer a form of dynamic spectral control [3,4]. The central attenuation wavelength of the LPFGs is highly sensitive to temperature, strain, bend or surrounding refractive index (SRI) changes. For these reasons filters based on the LPFGs have generated a significant interest for applications in the sensing field as well.Liquid crystals (LCs) are attractive candidates as a coating material since their properties can be controlled through temperature, optical, electrical and magnetic fields [5][6][7]. There are three key points for a good design in order to combine a LPFG and a LC into one component: selection of the LC refractive indices, inherent SRI sensitivity of the LPFG and the LC layer thickness. Majority of LCs have refractive indices that are higher than the refractive index of the silica glass. Thus, the LPFG sensitive to SRI is limited to the range where SRI is higher than the refractive index of the fiber cladding. In this case, the core modes couple to leaky modes [8] and the dependence on the resonance wavelength on the SRI is not so straightforward. So far, most of the studies have focused on the analysis of the SRI sensitivity when the

show abstract

Optical fibre long-period grating sensors: characteristics and application

Cited by 1,142 publications

References 98 publications

Highly sensitive volatile organic compounds vapour measurements using a long period grating optical fibre sensor coated with metal organic framework ZIF-8

Highly sensitive volatile organic compounds vapour measurements using a long period grating optical fibre sensor coated with metal organic framework ZIF-8

Metglas thin film based magnetostrictive transducers for use in long period fibre grating sensors

A Novel Electrically Tunable Long-Period Fiber Grating Using a Liquid Crystal Cladding Layer

Contact Info

Product

Resources

About