A Novel Method of Wireless Data Transfer Through a Variable Focus Lens-Induced Irradiance Modulation of a Gaussian Beam

Abstract

Mindful of several recent developments in the area of wireless optical data transfer over long and short distances, we present a novel technique to transmit data using an optical carrier. With this technique, the irradiance distribution of a Gaussian optical beam is controlled by passing it through an electronically controlled tunable lens (ECTL). The focal length of the ECTL is controlled by varying the root mean squared voltage of its input electrical drive signal, which alters the irradiance distribution of the Gaussian beam at any fixed plane located after the ECTL. These changes in the irradiance distribution can be interpreted as irradiance modulation with an applied input electrical signal. Variations in the input voltage signal to the ECTL result in variations in the photo-current produced inside a photo-detector of a finite active area. This paper aims to use this unique and simple method for free-space data transfer, and understand the limitations imposed by the currently available commercial ECTL technologies. With rapidly improving ECTL switching speeds and their already widespread use in mobile devices, this method promises an excellent alternative to existing point-to-point wireless data transfer schemes with minimum alterations to the existing hardware architecture of portable mobile devices.