25 resultados para 4point light 10W with miniature Wenner-Array
em Cambridge University Engineering Department Publications Database
Resumo:
Increasing the field of view of a holographic display while maintaining adequate image size is a difficult task. To address this problem, we designed a system that tessellates several sub-holograms into one large hologram at the output. The sub-holograms we generate is similar to a kinoform but without the paraxial approximation during computation. The sub-holograms are loaded onto a single spatial light modulator consecutively and relayed to the appropriate position at the output through a combination of optics and scanning reconstruction light. We will review the method of computer generated hologram and describe the working principles of our system. Results from our proof-of-concept system are shown to have an improved field of view and reconstructed image size. ©2009 IEEE.
Resumo:
Landslides occur both onshore and offshore, however little attention has been given to offshore landslides (submarine landslides). The unique characteristics of submarine landslides include large mass movements and long travel distances at very gentle slopes. Submarine landslides have significant impacts and consequences on offshore and coastal facilities. This paper presents data from a series of centrifuge tests simulating submarine landslide flows on a very gentle slope. Experiments were conducted at different gravity levels to understand the scaling laws involved in simulating submarine landslide flows through centrifuge modelling. The slope was instrumented with miniature sensors for measurements of pore pressure beneath the flow. A series of digital cameras were used to capture the flow in flight. The results provide a better understanding of the scaling laws that needs to be adopted for centrifuge experiments involving submarine landslide flows and gives an insight into the flow mechanisms. © 2010 Taylor & Francis Group, London.
Resumo:
We experimentally demonstrate a self-aligned approach for the fabrication of nanoscale hybrid silicon-plasmonic waveguide fabricated by local oxidation of silicon (LOCOS). Implementation of the LOCOS technique provides compatibility with standard complementary metal-oxide-semiconductor technology and allows avoiding lateral misalignment between the silicon waveguide and the upper metallic layer. We directly measured the propagation and the coupling loss of the fabricated hybrid waveguide using a near-field scanning optical microscope. The demonstrated structure provides nanoscale confinement of light together with a reasonable propagation length of ∼100 μm. As such, it is expected to become an important building block in future on-chip optoelectronic circuitry. © 2010 American Institute of Physics.
Resumo:
Reconfigurable liquid crystal microlenses employing arrays of multiwalled carbon nanotubes (MWNTs) have been designed and fabricated. The cells consist of arrays of 2 microm high MWNTs grown by plasma-enhanced chemical vapor deposition on silicon with a top electrode of indium tin oxide coated glass positioned 20 microm above the silicon and the gap filled with the nematic liquid crystal BLO48. Simulations have found that, while its nematic liquid crystal aligns with MWNTs within a distance of 10nm, this distance is greatly enhanced by the application of an external electric field. Polarized light experiments show that light is focused with focal lengths ranging from approximately 7 microm to 12 microm.