Large-area origination and replication of microstructures with optical functions

Structuring surfaces on a microscopic scale allows to modify their optical properties. The exact tailoring of these properties requires very precise manufacturing techniques. On large areas, mainly replication techniques allow competitive production cost. This paper addresses the challenge of originating and replicating microstructures with optical functions with dimensions between 200nm and 50m on areas of up to half a square meter. The whole experimental process chain is described and discussed. For the microstructure origination, interference lithography was used. An argon ion laser was chosen as a coherent light source at a wavelength of 364nm. Periodic and stochastic interference patterns were recorded in positive photoresist by using large interferometer set-ups. Structures with good homogeneity were originated on areas of up to 4800 cm2 by optimizing the set-up and the photoresist processing. By carefully modeling resulting resist profiles it was possible to orig inate a wide variety of surface-relief profiles including prismatic ones. Different replication techniques like hot compression molding and UV casting are discussed. Some applications of large-area micro-structured films and sheets are presented

Household energy use: a study investigating viewpoints towards energy efficiency technologies and behaviour

Improving the energy efficiency of our homes presents an excellent opportunity to reduce greenhouse gas emissions and increase thermal comfort. However, a shortfall exists between the full potential and realised adoption of energy efficiency measures, a phenomenon termed the ‘Energy Efficiency Gap’. To better understand the Energy Efficiency Gap, this research identified household viewpoints towards energy, and stated preferences towards energy efficiency technologies and behaviour. The research was carried out through interviews and a Q Study in the cities of Manchester and Cardiff, alongside a questionnaire. The results revealed a range of nuanced viewpoints, which mapped onto three principal household themes: energy use in terms of the environment; energy in relation to money; and apathy towards energy. A key finding was the small number strong correlations between distinct energy viewpoints and specific energy efficiency technologies or behaviours. This result implies that being environmentally aware and actively concerned about energy efficiency does not in itself lead to a stated desire, or even, intention to install energy efficient technologies. The wider implication is that households that hold proactive energy efficiency viewpoints based on environmental concern may still require specifically targeted incentives to encourage the uptake of energy efficiency measures, i.e. their proactive and environmental beliefs are not alone enough to motivate them to improve the energy efficiency of their home.EPSR