John Canning

The utilisation of plants directly as quantifiable natural sensors is proposed. A case study measuring surface wettability of Aucuba japonica, or Japanese Laurel, plants using a novel smartphone field interrogator is demonstrated. This plant has been naturalised globally from Asia. Top-down contact angle measurements map wettability on-site and cha...

The influence of isochronal and isothermal annealing on grating regeneration in single mode silica optical fibers has been investigated. By rapid annealing of Type-I grating under isothermal conditions we demonstrated that the underlying processes in the fiber that contribute toward grating regeneration work best around a certain temperature and th...

Rapid cooling, or quenching, during regeneration of seed gratings in standard single-mode silica optical fiber is explored. It is shown that regeneration can be broken up into stages in time. The novel, to the best of our knowledge, method of “split annealing” offers a unique tool for optimizing regeneration and studying fundamental glass science w...

To address climate change, environmental monitoring and wellness more generally on a global scale, a new concept is presented - the bionic internet-of-things, or b-IoT. We propose the utilization of existing organic “sensor” technology that nature has provided and discuss a future adapting these to an existing inorganic internet to truly open up a...

The government AgriTech Expert Working Group has provided a detailed overview of the practical challenges domestic Australian farmers have to deal with when digitising their farms through the implementation of connected sensor technologies, motivated by the predicted growth of the sector to AUD 100 billion by 2030. In addressing these issues, of wh...

The utilisation of plants directly as quantifiable natural sensors is proposed. A case study measuring surface wettability of Aucuba japonica, or Japanese Laurel, plants using a novel smartphone field interrogator is demonstrated. This plant has been naturalised globally from Asia. Top-down contact angle measurements map wettability on-site and cha...

Annealing effects on optical losses in silica optical fiber drawn from 3D-printed preform were investigated. An irreversible reduction in loss was observed through multiple annealing cycles at a temperature $T =$ 800 ° C . Changes in Raman spectroscopy confirm densification of the core as the stresses in glass relax with annealing. The temper...

Single and multi-core preforms doped with Bi and Er are fabricated using additive manufacture and drawing into optical fibre. We observe an increasing trend towards shape distortion with increasing number of cores. This is explained by noting that the composite effective softening point falls as the number of doped cores rises. The use of a silica...

A fused deposition modeling (FDM) 3D printer extruder was utilized as a micro-furnace draw tower for the direct fabrication of low-cost optical fibers. An air-clad multimode microfiber was drawn from optically transparent polyethylene terephthalate glycol (PETG) filament. A custom-made spooling collection allows for an automatic variation of fiber...

We review recent results analyzing a 3D printed optical fibre and show how ignoring the core-cladding interface to use an effective index approximation when interpreting fibre-based measurements can lead to potential misunderstandings of photo-dependent phenomena, in this case the origin of optical loss in 3D printed fibres.

The peak strength of regenerated gratings is found to be maximum around a certain temperature. The underlying transformations and their mechanisms can be frozen in at any stage during regeneration by rapid cooling of fibre.

The use of anti-reflection coatings on 3D-printed components to reduce both Fresnel reflections and scattering is explored. Two similar photo-initiated acrylic commercial material structures, known as Standard Clear (SC: T~60% @ λ = 800 nm) and VeroClear (VC: T~90% @ λ = 800 nm), used specifically for optical components, are examined. The refractiv...

The SARS-Coronavirus-2 (SARS-CoV-2) infectious disease, COVID-19, has spread rapidly, resulting in a global pandemic with significant mortality. The combination of early diagnosis via rapid screening, contact tracing, social distancing and quarantine has helped to control the pandemic. The absence of real time response and diagnosis is a crucial te...

This paper presents an overview of recent developments in smartphone spectrometers focusing on light collection, dispersion, detection and spectral calibration. These spectrometers potentially offer unprecedented field diagnostics that can exploit real-time IoT edge data transfer into the cloud and back. However, there are technical challenges if t...

A robust and adaptive smartphone-based colorimetric sensing platform is reported. It utilizes multiple regression analysis to address nonlinear concurrent variations of multiple sensing variables. The instrument can perform colorimetric measurement with improved accuracy over a wide range where both color and intensity information of a colorimetric...

A multichannel smartphone spectrometer exploiting multiple identical diffraction orders of a customized 2D diffractive element is reported. The instrument utilizes diffraction grating holographic imaging to converge and capture the multiple diffraction orders simultaneously within the limited field-of-view of the smartphone’s camera detector. This...

The impact of drawing pressure on the structure of solid-core structured optical fibres (SOFs) is investigated. A modified single-capillary model to cater for multi-capillary structural constraint in the radial axis within a larger single capillary draw, whilst retaining analytical simplicity, is proposed and shown to give improved fits with experi...

To address the challenge of appropriate cementitious materials that can support future optical fibre sensors with reduced strains for smart city infrastructure, reducing structural heterogeneity by integrating diatomous earth is proposed. A series of samples made up of commercial grade instant mortar and an increased percentage of diatomous earth a...

A robust and adaptive smartphone-based colorimetric sensing platform is reported. It utilizes multiple regression analysis to address nonlinear concurrent variations of multiple sensing variables. The instrument can perform colorimetric measurement with improved accuracy over a wide range where both color and intensity information of a colorimetric...

Fiber drawing from a 3D printed perform was recently discussed to go beyond the limitations of conventional optical fiber manufacturing in terms of structure and materials. In this work, the photosensitivity of silica optical fibers to femtosecond laser light, and fabricated by 3D printing a preform, is investigated. The writing kinetics and the th...

A study on birefringence compensation of highly asymmetric germanosilicate fibre drawn from a 3D printed preform is carried out. Surprisingly large compensation is locked in when twist is released, amounting to more than 80% compensation. Large bandgap attenuation is observed when gratings are written into this fibre.

A brief assessment is made of existing wireless and photonic sensor networks in buildings. It follows interests in the premium hotel sector to assess the feasibility integrating fibre optic sensors with existing fibre optic based communications

3D printing is a disruptive technology that could revolutionise the fabrication of optical fibre by offering greater flexibility and diversity in material and structure designs. This paper reviews the recent research and development of material and fabrication techniques toward 3D printing-based polymer optical fibre (POF) and silica optical fibre...

Using induced UV attenuation across a twisted fiber asymmetric core drawn from a 3D printed preform, linear fiber Bragg gratings (FBGs) are produced on one side of the core. By removing the twist, a helical grating with a period matching the twist rate is produced. Balancing the rate with the polarization beat length in a form birefringent fiber al...

A robust multichannel smartphone spectrometer exploiting multiorder diffraction imaging on a smartphone camera is reported. The instrument utilizes a thin film diffractive element generating multiple orders of diffracted light from a broadband visible source (white LED, λ = 400–700 nm). The smartphone's CMOS camera captures all the diffraction or...

In 2020 the world is experiencing a pandemic when a virus emerged from Wuhan, China the year before, at this stage identified from a bat species through an intermediary market animal host to humans [1]. Politics creates uncertainty: testing the claims it accidentally came out of a Wuhan laboratory, a literature search reveals strong US-China resear...

The employment of type-I pyrethroids for airplane disinfection in recent years underlines the necessity to develop sensing schemes for the rapid detection of these pesticides directly at the point-of-use. Antibody-gated indicator-releasing materials were thus developed and implemented with test strips for lateral-flow assay-based analysis employing...

Fiber Bragg gratings are embedded within 3D printed polymer packages. Information about both induced and applied stresses, and operator error, can be determined from the observed spectral shifts and chirping. A novel way to produce packaged broadband gratings, with $\Delta {\lambda _{\rm BW}}\gt {7}\;{\rm nm/cm}$ΔλBW>7nm/cm, is proposed and demonst...

This research aims to promote photocatalysis of endocrine disrupting chemicals (EDCs) in water. Two reactor setups with (i) modified air-clad optical fibres and (ii) waterproof LED strips were utilised to transmit light to photocatalysts P25 TiO2 and gold-modified TiO2 (Au-TiO2). The performances to photodegrade 17α-ethynylestradiol (EE2) and estri...

Based on 3D printing technology, multi-core doped silica optical fibre has been fabricated. The demonstration heralds a new fibre manufacturing milestone one that enables the design of fibres not previously feasible.

A robust multi-channel smartphone spectrometer is reported by utilizing the multiple diffraction orders of an ordinary diffraction grating.

Additive manufacture (AM) offers a simple route to packaging components such as fibre Bragg gratings. Further, polymers with higher solid state densities than liquid state enable a simple approach to tightly fixing optical components with AM packages. With applied load and using printer directionality, chirping fibre Bragg gratings becomes possible...

Embedding fibre Bragg gratings (FBGs) in memory retaining flexible thermo plastic copolyester is assessed.

We demonstrate that under appropriate conditions it is possible to build in tolerance to poor design of a structured optical fibre like photonic crystal fibre. During drawing its internal symmetry of the structure is improved.

In response to hotel industry feedback a simulated power analysis of a fibre Bragg grating (FBG) wavelength division multiplexed (WDM) sensing system integrated within a passive optical local area network (POLAN) for remote structural health monitoring (SHM) is assessed.

Combined rocking filters and polarisation balanced fibre Bragg gratings are demonstrated in a 3D printed optical fibre.

A self-contained smartphone-based colorimetric sensing platform adaptable for multiple analytes is demonstrated. Concurrent variation of multiple optical sensing parameters is addressed using multiple nonlinear regression analysis.

This paper reports a 3D printing intelligent insole gait monitoring system based on embedded fiber Bragg grating. The smart insole combines 3D printing technology and fiber Bragg gratings (FBGs) sensors providing high sensitivity and end-point low cost. Results using pressure points measured by four FBGs are sufficient to differentiate foot loads a...

The application of self-contained field-portable, internet connected spectroscopic diagnostics in food analysis using a fibre endoscopic smart fluorimeter is reported. A UV-induced fluorescence is used to measure the quality of olive oils, distinguishing between extra virgin and others within a smartphone platform. When excited at $\lambda \sim ~3...

Silica optical fiber was drawn from a three-dimensional printed preform. Both single mode and multimode fibers are reported. The results demonstrate additive manufacturing of glass optical fibers and its potential to disrupt traditional optical fiber fabrication. It opens up fiber designs for novel applications hitherto not possible.

In this paper, various types of high temperature fibre Bragg gratings (FBGs) are reviewed, including recent results and advancements in the field. The main motivation of this review is to highlight the potential of fabricating thermally stable refractive index contrasts using femtosecond (fs) near-infrared radiation in fibres fabricated with non-co...

Excitation of surface waves on conducting materials provides a near resistance-free interface capable of a material glissade either by plasmon forces or by optical beam tractors. Analogous to an ice hockey rink, as proof-of-principle plasmon-assisted optical traction, or hoovering, of water drops on a gold surface is demonstrated. Changes in the co...

Conventional silica fiber fabrication using chemical vapor deposition (CVD) has been a successful optical fiber fabrication platform, producing the bulk of commercial optical fibers and fiber amplifiers that form the backbone of today’s Internet. As the Internet evolves into a so-called ubiquitous “Internet of things,” or IoT, the role of optical f...

Transmission Mueller-matrix spectroscopic ellipsometry is applied to study femtosecond laser induced nanogratings in silica glass in a wide spectral range 250–1800 nm. By using differential decomposition of the Mueller matrix, the circular birefringence and dichroism of femtosecond laser irradiated SiO2 are quantified for the first time in the UV a...

Excitation of surface waves on conducting materials provides a near resistance-free interface capable of a material glissade either by plasmon forces or optical beam tractors. Analogous to an ice hockey rink, as proof of principle plasmon assisted optical traction, or hoovering, of water drops on a gold surface is demonstrated. Variability in thres...

Top-down contact angle (CA) measurements [1] are used to characterize the green leaves and purple flowers of both old and young the Cattleya warneri orchids. Top down CA allows the characterization of large surfaces away from the leaf edge, avoiding traditional cutting required for side view CA measurement. This allows large area mapping without da...

This paper presents three applications of carbon fiber reinforced polymer with integrated FBG sensor systems in biomechanics. In vivo tests were performed showing that the sensors are robust for the different applications.

Horses are empowered by using a specialized network of optical fiber sensors integrated to augmented reality technology which enhances their communication with the rider/owner during training, racing and possibly entire life.

This article presents two in vivo instrumentation techniques to study the different types of gait of horses performing athletics using fiber Bragg gratings (FBG). These techniques can be used as an auxiliary tool in the early diagnosis of injuries related to the horse’s locomotor system, mainly in the distal portion of the digit, one of the most co...

The special features of photonic crystal fibres (PCFs) are achieved by their air hole structures. PCF structure is determined and formed by its origin preform design and drawing process. Therefore, structure formation dynamics in drawing PCF is important for the fabrication of PCF achieving desirable structure and thus the intended feature. This pa...

This work presents a method to measure the temperature of the fixed and mobile bearings of a crankshaft in a large diesel engine using optical fiber Bragg gratings (FBGs). The FBG sensor development and the encapsulation with stainlesssteel tube are described. The sensors were tested in a large diesel engine in full operation and the results demons...

A review of the literature offers an explanation for the large anomalous electro-optic (e.o.) effect reported by Fujiwara et al. in 1994. It is based on the large e.o. coefficient of ordered water at an interface measured in recent years >1000 pm/V. More broadly, the concept of water-based photonics, where water could be a new platform material for...

The papers in this special issue were presented at the 25th International Conference on Optical Fiber Sensors that was held at Maison Glad Hotel, Jeju, Korea, from April 24 to 28, 2017.

Fibre Bragg grating regeneration involves, at its simplest, the annealing and resurrection of a seed FBG through thermal annealing. Micro-Raman spectroscopy provides evidence that inscribing the seed structure has changed the thermal history of the glass so that whilst the annealing is identical in all areas, the local glass relaxation is different...

3D-printing is changing the way research is being conducted. By enabling the ready demonstration of prototype devices and instruments, 3D printing accelerates the adaptation of IoT technologies going beyond simple, latency-enhancing sensors. Prototyping and custom packaging is easier, rapid and increasingly low cost, circumventing traditional appro...

An explanation is offered for the large anomalous electro-optic (e.o.) effect reported by Fujiwara in 1994. It is based on the large e.o. coefficient of ordered water at an interface measured in recent years. The concept of water-based photonics is introduced, suggesting that liquid states of matter can allow ready shaping and exploitation of many...

Top-down contact angle measurements have been validated and confirmed to be as good if not more reliable than side-based measurements. A range of samples, including industrially relevant materials for roofing and printing, has been compared. Using the top-down approach, mapping in both 1-D and 2-D has been demonstrated. The method was applied to st...

Top-down contact angle measurements have been validated and confirmed to be as good if not more reliable than side-based measurements. A range of samples, including industrially relevant materials for roofing and printing, has been compared. Using the top-down approach, mapping in both 1-D and 2-D has been demonstrated. The method was applied to st...

A dual 830 and 980 nm pumping scheme is proposed aiming at broadening and flattening the spectral performance of bismuth/erbium codoped multicomponent fiber (BEDF). The spectral properties of distinct Bi active centers (BACs) associated with germanium (BAC-Ge), aluminium (BAC-Al), phosphorus (BAC-P) and silicon (BAC-Si) are characterized under sing...

A smartphone fluorimeter capable of time-based fluorescence intensity measurements at various temperatures is reported. Excitation is provided by an integrated UV LED (370 nm) and detection obtained using the in-built CMOS camera. A Peltier is integrated to allow measurements of the intensity over T = 10 to 40 C with a maximum temperature resolutio...

The temperature distribution within extrusion nozzles of three low-cost desktop 3D printers is characterized using fiber Bragg gratings (FBGs) to assess their compatibility as micro-furnaces for optical fiber and taper production. These profiles show remarkably consistent distributions suitable for direct drawing of optical fiber. As proof of princ...

This paper presents the first time studies on chemical sensing characteristics of HF etched thermally regenerated fiber Bragg grating (FBG). No shift in Bragg wavelength, λBragg, of the FBG during HF etching has been observed for thermally regenerated FBGs. This contrasts with etching of conventional Type-I gratings both with and without annealing...

The temperature distribution within extrusion nozzles of three low-cost desktop 3D printers is characterized using fiber Bragg gratings (FBGs) to assess their compatibility as micro-furnaces for optical fiber and taper production. These profiles show remarkably consistent distributions suitable for direct drawing of optical fiber. As proof of princ...

Multi-point surface plasmon resonance (SPR) excitation using a skew ray within a multimode plastic optical waveguide coated with gold, Au, is reported. The effect of skew rays on the performance of SPR has been studied both theoretically and experimentally. The approach also entails a novel method of measuring the SPR angle that is in agreement wit...

Multipoint surface plasmon resonance (SPR) excitation using a skew ray within a multimode plastic optical waveguide coated with gold, Au, is reported. The effect of skew rays on the performance of SPR has been studied both theoretically and experimentally. The approach also entails a novel method of measuring the SPR angle that is in agreement with...

I have just come out of being in the throes of organising the Brag Gratings, Photosensitivity and Poling Conference [1], globally recognised as BGPP, just held in Sydney within the Sydney Masonic centre, an exquisite piece of aptly called brutalist architecture (the term coming from the French “beton brut” or raw concrete), only recently softened b...

A new approach to fabricating nanobot technology based on charge transfer with optical excitation is proposed.

Optical fibre is drawn from a dual-head 3D printer fabricated preform made of two optically transparent plastics with a high index core (NA ~ 0.25, V > 60). The asymmetry observed in the fibre arises from asymmetry in the 3D printing process. The highly multi-mode optical fibre has losses measured by cut-back as low as {\alpha} ~ 0.44 dB/cm in the...

Education is changing – you only have to read the wonderful array of articles within LinkedIn and elsewhere that reflect that change across so many disciplines. It is a result of both changing business models through globalisation and technology. Such change is inevitably interspersed with various interpretations and manipulations, with emotive and...

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An optical fiber-based smartphone spectrometer incorporating an endoscopic fiber bundle is demonstrated. The endoscope allows transmission of the smartphone camera LED light to a sample, removing complications from varying background illumination. The reflected spectra collected from a surface or interface is dispersed onto the camera CMOS using a...

Room-temperature self-assembly was used to fabricate a periodic array of uniformly sized Al3+-doped SiO2 nanoparticles (Al−SiO2NPs, 20–30 nm). The uniform mesoporous structure was suitable for uniformly incorporating and distributing Pt nanoparticles (PtNPs), which were used as hydrogen-evolution catalysts in artificial photosynthetic systems, with...

Correction for 'Water on Au sputtered films' by J. Canning et al., Chem. Commun., 2014, 50, 9172-9175.

Glass modifications on the nanoscale occurring after femtosecond laser irradiation give rise to strong form birefringence. This birefringence is related to the so-called nanogratings. By observing induced tracks in various germanosilicate glasses using scanning electron microscopy (SEM), we demonstrate that porous nanoplanes can be formed not only...

Polarization mode coupling (PMC) and related effects from writing fiber Bragg gratings in polarization maintaining fiber (FBGs-in-PMF) are observed experimentally for the first time by optical fiber coherence domain polarimetry (OCDP) using a broadband light source. PMC is another useful aspect of FBG-in-PMF besides Bragg wavelength and its possibl...

Nanoscale glass milling with mild thermal annealing is proposed and shown to occur within a tri-material composite optical fibre. Evidence of glass relaxation with annealing is inferred directly through measured diameter changes in the core and inner cladding of the long period gratings (LPGs) (Δφcore = (0.13 ± 0.05) μm; Δφinner cladding = -(0.5 ±...

Abstract A structured optical fiber (also called Fresnel fiber, Bragg fiber, photonic crystal fiber, photonic bandgap fiber, air-clad fiber, holey fiber, hole-assisted fiber, microstructured fiber, nanostructured fiber, and so on) is an optical fiber that obtains its properties by controlling the structure and pattern of structure within the length...

The dependency between erasing and subsequent regeneration of a Type-I grating in H2 loaded standard single mode fiber as a function of T is explored with accelerated annealing.

We observe the first chemical complexity for Type IA FBG growth under prolonged UV laser exposure. Out-of-phase oscillatory behaviour in GeOH/SiOH formation provides evidence of laser-driven autocatalysis and chemical origins for grating formation.