11 research outputs found

    Anti-Spoof Reliable Biometry of Fingerprints Using En-Face Optical Coherence Tomography

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    Optical coherence tomography (OCT) is a relatively new imaging technology which can produce high-reso- lution images of three-dimensional structures. OCT has been mainly used for medical applications such as for ophthalmology and dermatology. In this study we demonstrate its capability in providing much more re- liable biometry identification of fingerprints than conventional methods. We prove that OCT can serve se- cure control of genuine fingerprints as it can detect if extra layers are placed above the finger. This can pre- vent with a high probability, intruders to a secure area trying to foul standard systems based on imaging the finger surface. En-Face OCT method is employed and recommended for its capability of providing not only the axial succession of layers in depth, but the en-face image that allows the traditional pattern identification. Another reason for using such OCT technology is that it is compatible with dynamic focus and therefore can provide enhanced transversal resolution and sensitivity. Two En-Face OCT systems are used to evaluate the need for high resolution and conclusions are drawn in terms of the most potential commercial route to ex- ploitation

    Millbank tendency: the strengths and limitations of mediated protest ‘events’ in UK student activism cycles

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    UK students’ desire to create disruptive, media-friendly ‘events’ during the 2010-11 protests against fees and cuts is reflective of wider cycles and processes in student activism history. First, constant cohort turnover restricts students’ ability to convert campaigns into durable movements, necessitating that they must periodically ‘start from scratch’. This informs a second process, namely the need to gain the attention of mainstream media, as this can potentially amplify students’ grievances far beyond their own organisational capacities. Both have shaped student activism over the past fifty years, compelling contemporary students to create protest events that live up to their radical history. These processes were evident in autumn 2010, when an NUS demonstration saw students attack and briefly occupy Conservative Party headquarters at 30 Millbank. The protest’s mass mediation was central to activists’ ‘eventing’ processes, and provided the spark for the radical UK-wide campaign that followed. Yet once the fees bill was passed by Parliament, students’ dependency on mainstream media cycles was quickly exposed. With ‘mediatization’ tendencies having dogged student activism since the sixties, this article argues that creating ‘events’ epitomises students’ longstanding strengths and limitations as society’s ‘incipient intelligentsia’ (Rootes, 1980: 475)

    A rapid method of measuring dispersion in low coherence interferometry and optical coherence tomography systems

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    A method of using multiple spectral channels to measure dispersion mismatch in optical coherence tomography (OCT) and low coherence interferometry systems is presented. The method is tested on a time domain OCT system in comparison to the measurement of the auto-correlation profile. The method is quicker to implement and is more sensitive than the measurement of the auto-correlation profile

    Visualization 1: High-speed adaptive optics for imaging of the living human eye

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    AOSLO video with AO correction for wavefront aberration at 100 Hz (Media 1). Originally published in Optics Express on 07 September 2015 (oe-23-18-23035
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