Summary: | Visible light communications (VLC) is an important emerging field aiming to use optical communications to supplement Wi-Fi. This will greatly increase the available bandwidth so that demands for ever-higher data rates can be met. In this vision, solid state lighting will provide illumination whilst being modulated to transmit data. An important obstacle to realizing this vision are receivers which need to be inexpensive, sensitive, fast and have a large field of view. One approach to increasing the sensitivity of a VLC receiver is to increase the area of the receiver’s photodetector, but this makes them expensive and slow. An alternative approach is to use optical elements to concentrate light, but conservation of étendue in these elements limits their field-of-view. In this letter we demonstrate novel antennas that overcome these limitations, giving fast receivers with large collection areas and large fields of view. Our results exceed the limit of étendue, giving an enhancement of light collection by a factor of 12, with field of view semi-angle of 60° and we show a 3-fold increase in data rate.
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