Browsing by Author "Tatam, Ralph P."

Browsing by Author "Tatam, Ralph P."

Sort by: Order: Results:

  • AI-Sawaf, Firas (Cranfield University, 2005-06)
    In the field of optical interferometry, two-dimensional projections of light interference patterns are often analysed in order to obtain measurements of interest. Such interference patterns, or interferograms, contain ...
  • Tatam, Ralph P.; Davies, Jeremy C.; Buckberry, Clive H.; Jones, Julian D. C. (International Society for Optical Engineering; 1999, 1990-12-31)
    The incorporation of laser diodes and monomode fibre optics into an Electronic Speckle Pattern Interferometer (ESPI) has led to the development of a novel holographic surface contouring system. Height contours are obtained ...
  • Khaliq, Sarfraz; James, Stephen W.; Tatam, Ralph P. (Iop Publishing Ltd, 2002-05-05)
    Surrounding a long period grating, fabricated in a standard optical fibre, with a material with a high thermo-optic coefficient enhances the temperature sensitivity of a long period grating. Temperature sensitivities as ...
  • Rigas, E.; Correia, Ricardo N.; Stathopoulos, N. A.; Savaidis, S. P.; James, Stephen W.; Bhattacharyya, Debabrata; Kirby, Paul B.; Tatam, Ralph P. (SPIE, 2014-06-02)
    A polling topology that employs optical switching based on the properties of erbium-doped fibres (EDFs) is used to interrogate an array of FBGs. The properties of the EDF are investigated in its pumped and un-pumped states ...
  • Wei, C. Y.; Ye, Chen-Chun; James, Stephen W.; Tatam, Ralph P.; Irving, Phil E. (2001-06-25)
    This paper developed a method to evaluate the strain transfer efficiency of fibre Bragg grating sensors to host structures. Various coatings were applied to fibre Bragg grating sensors after being fabricated. They were ...
  • James, Stephen W.; Cheung, C. S.; Tatam, Ralph P. (2007-10-01)
    The sensitivity of attenuation bands corresponding to the 2nd order coupling to cladding modes by a fibre optic long period grating (LPG) to the deposition of nanostructured coatings is investigated and compared with ...
  • Tothill, Alexander M.; Partridge, Matthew; James, Stephen W.; Tatam, Ralph P. (IOP Publishing: Hybrid Open Access, 2017-02-15)
    A 3D-printed microfluidic device was designed and manufactured using a low cost ($2000) consumer grade fusion deposition modelling (FDM) 3D printer. FDM printers are not typically used, or are capable, of producing the ...
  • Mullaney, Kevin (Cranfield University, 2016-11)
    This thesis describes the processes used to manufacture optical fibre tapers and tapered long period gratings (TLPGs) using a CO2 laser. A semi-automated system for fabricating adiabatic and non-adiabatic tapers with ...
  • Korposh, Sergiy; James, Stephen W.; Lee, Seung-Woo; Topliss, Stephen M.; Cheung, Sammy C.; Batty, William J.; Tatam, Ralph P. (Optical Society of America (OSA), 2010-06-07)
    A novel approach to chemical application of long period grating (LPG) optical fibers was demonstrated, which were modified with a film nanoassembled by the alternate deposition of SiO2 nanoparticles (SiO2 NPs) and ...
  • Flannery, D.; James, Stephen W.; Tatam, Ralph P.; Ashwell, Geoffrey J. (Osa Optical Society of America, 1999-12-20)
    Fiber-optic chemical sensing has been demonstrated with a side-polished single- mode optical fiber, evanescently coupled to chemically sensitive Langmuir- Blodgett (LB) overlay waveguides. The sensors exhibit a ...
  • Correia, Ricardo N.; Li, Jin; Staines, Stephen E.; Chehura, Edmon; James, Stephen W.; Tatam, Ralph P.; Kutner, Joel; Dewhurst, Paul; Ferreira, Pedro (International Society for Optical Engineering; 1999, 2009-12-31)
    An effective-soil-pressure sensor for geotechnical applications based on Fibre Bragg Gratings is presented. The sensor simultaneous measures total soil pressure and pore pressure, allowing the calculation of the effective ...
  • Li, Jin; Correia, Ricardo N.; Chehura, Edmon; Staines, Stephen E.; James, Stephen W.; Tatam, Ralph P. (International Society for Optical Engineering; 1999, 2010-12-31)
    The measurement of ground movement is an essential part of many geotechnical engineering operations. For decades, inclinometer systems have traditionally been used for this purpose to provide crucial information to ...
  • Buggy, Stephen J.; Chehura, Edmon; Skordos, Alexandros A.; Dimopoulos, A.; James, Stephen W.; Partridge, Ivana K.; Tatam, Ralph P. (2007-06-17)
    Optimum performance from advanced composites requires careful control of the resin matrix during cure. This is to ensure there are no cure induced voids and to minimise the build up of internal stresses. Careful control ...
  • Ford, Helen D.; Tatam, Ralph P. (Iop Publishing Ltd, 2007-01-01)
    An imaging fibre bundle is incorporated into a full-field imaging OCT system, with the aim of eliminating the mechanical scanning currently required at the probe tip in endoscopic systems. Each fibre within the imaging ...
  • Casaubieilh, P. (Cranfield University, 2006)
    The aim of the project was to develop the Fizeau interferometer configuration to take advantage of the benefits derived from its “downlead insensitivity” to temperature and polarisation fading. This sensing interferometer ...
  • Chowdhury, S. A. (Cranfield University, 2015-09)
    Hydrogen is an explosive and flammable gas with a lower explosive limit of just 4% volume in air. It is important to monitor the concentration of hydrogen in a potentially hazardous environment where hydrogen may be ...
  • James, Stephen W.; Tatam, Ralph P. (Institute of Physics, 2006-07-01)
    A review of optical fibre devices employing nano-structured coatings is presented. Active and passive coatings, deposited using the Langmuirâ  Blodgett and electro-static self-assembly techniques, have been utilised ...
  • Kissinger, Thomas; Correia, Ricardo N.; Charrett, Thomas O. H.; James, Stephen W.; Tatam, Ralph P. (Institute of Electrical and Electronics Engineers, 2016-02-18)
    Using a novel range-resolved interferometric signal processing technique based on the sinusoidal optical frequency modulation of a cost-effective laser diode, a fibre sensing approach termed fibre segment interferometry ...
  • Kissinger, Thomas; Charrett, Thomas O. H.; Tatam, Ralph P. (Iop Publishing Ltd, 2013-09-30)
    A novel optical signal processing scheme for multiplexing fibre segment interferometers is proposed. The continuous-wave, homodyne technique combines code-division multiplexing with single-sideband modulation. It uses only ...
  • Khaliq, Sarfraz (Cranfield University, 2003-03)
    Long period gratings (LPGs) are formed by inducing a permanent periodic modulation of the refractive index (RI) of the core of an optical fibre. The transmission spectrum of the LPG contains a series of attenuation bands ...