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Amblyopia is a significant issue for children worldwide, and current treatment methods have drawbacks that can hinder treatment effectiveness and/or patient experience. This study proposes a new treatment method using holographic diffusers while also comparing their optical characteristics to a current treatment method (Bangerter foils). Holographic diffusers were developed by optically patterning thin polymer layers on a micron scale. Two compositions of photopolymer (acrylamide and diacetone acrylamide based) are analysed herein. Characterisation shows that holographic diffusers of either composition can achieve a wide range of on-axis intensity reductions, allowing for precise and customisable treatment levels by altering recording exposure time in a low-cost and durable manner.

Effect of material shrinkage on hologram diffraction efficiency

The international mobilisation of tertiary students is increasing from 0.8 million in 1975 to 3.5 million worldwide by 2016 (OECD, 2018). This increasingly fluid student migration, supported with various European initiatives, the Erasmus exchange program (since 1987) and the Bologna Declaration (since 1999), have influenced the profile of students within the Irish higher education system. By 2016, international students comprised 5.1% of total tertiary students in Ireland (OECD, 2018). According to Irish and UK research, lecturers have an important role in facilitating integration (British Council, 2014; Irish Council for International Students, 2017). However, for most faculty, the term internationalisation of the curriculum was unfamiliar (Clarke, Hui Yang & Harmon, 2018) and faculty also had mixed views on a need to explicitly address cultural and language issues in their learning outcomes or assessment tasks. Although some faculty viewed intercultural training as important most had not received this kind of support (Clarke et al., 2018). This report focuses on the integration challenges international students face, and what best-practice recommendations are available to assist lecturers in aiding integration.

Purpose: To compare three clinical corneal topographers in their ability to describe the posterior corneal shape. Methods: The corneas of 30 eyes of 30 healthy subjects were measured twice with a dual Scheimpflug camera (Galilei), a scanning slit system (Orbscan), and a single Scheimpflug camera (Pentacam). Elevation data describing the posterior corneal shape were fitted with Zernike polynomials. Mean values with standard deviation (SD), test-retest variability (coefficient of repeatability), and inter-device variability were determined for the defocus (z[2,0]), astigmatism (z[2,-2], z[2,2]), coma (z[3,-1], z[3,1]), trefoil (z[3,-3], z[3,3]), and spherical aberration (z[4,0]) coefficients, for 5.5 and 8.0 mm diameter zones. Results: At 5.5 mm, the mean (SD) Zernike coefficients were, for the Galilei, +176 (7), +0.1 (1.3), -6.6 (2.4), +0.3 (0.8), +0.1 (0.8), -0.4 (0.5), +0.9 (0.6), and 1.6 (0.6) for z[2,0], z[2,-2], z[2,2], z[3,-1], z[3,1], z[3,-3], z[3,3], and z[4,0], respectively. The coefficients of repeatability ranged from 0.3 to 4.3 μm for the Galilei, from 1.6 to 5.2 for the Orbscan, and from 0.3 to 2.0 μm for the Pentacam; the repeatability was similar for Galilei and Pentacam (p=0.43) and significantly poorer for the Orbsan (p Conclusions: For the assessment of the posterior corneal shape, the repeatability is generally good for the Galilei and Pentacam but poor for the Orbscan. Interdevice variability between Galilei and Pentacam compromises the exchangeability of the devices’ measurement values.

The U.S. Navy anticipates moving to a shipboard high-energy laser program of record in the fiscal year 2018 and achieving an initial operational capability by 2020. The design of a distance support capability within the high-energy laser system was expected to assist the Navy in reaching this goal. This capstone project explored the current Navy architecture for distance support and applied system engineering methodologies to develop a conceptual distance support framework with application to the high-energy laser system. A model and simulation of distance support functions were developed and used to analyze the feasibility in terms of performance, cost, and risk. Results of this capstone study showed that the implementation of distance support for the high-energy laser system is feasible and would reduce the total ownership cost over the life of the program. Furthermore, the capstone shows that moving toward the team’s recommended distance support framework will address current gaps in the Navy distance support architecture and will provide a methodology tailored to modern enterprise naval systems. http://archive.org/details/distancesupporti1094545248 Approved for public release; distribution is unlimited.

Approximately 20 million cataract operations are performed per year worldwide, routinely removing the opaque cataractous lens and implanting an artificial intraocular lens (IOL). Modern technologies used to treat cataract are highly sophisticated and the operation involves remarkable skills; however the IOL power calculation in certain circumstances can be unsatisfactory. Currently the calculation of required IOL power is based on formulas developed from the paraxial geometrical optics equations and/or statistical analysis of retrospective cases. This work aims to improve upon the methodologies currently used to predict required IOL power, particularly for unusual eyes with extreme ocular biometry (e.g. extreme axial length or corneal shape). This work also demonstrates the usefulness of individual personalised ray-tracing eye models in investigations of IOL designs proposed to correct the higher order aberrations of the eye.