Free-space powering using 3W high-power laser source at 980nm

Optical power transfer is a promising technology for wireless energy transmission, with two primary implementation approaches: Power over Fiber (PoF) and free-space power delivery. PoF utilizes optical fibers to transmit power over a guided medium, providing advantages such as minimal environmental interference and high efficiency. In contrast, freespace optical power transfer enables wireless energy delivery. Free-space optical power transfer is useful for applications, where physical connections are impractical, such as remote sensors, space systems, and industrial automation. This paper presents a free-space optical power transfer setup designed for power transmission over a 5-meter distance in standard atmospheric conditions. The system utilizes a High-Power diode Laser Source with an optical input of 3 W at a wavelength of 980 nm. The laser output is delivered through a multimode (MM) optical fiber with core diameter 105 μm and collimated using a 30 mm lens for efficient beam propagation. At the receiving end, a Gallium Arsenide (GaAs) Photonic Power Converter (PPC) is employed for optical-to-electrical energy conversion, with a 400 mm lens used to collect and focus the transmitted light onto the PPC. A Keithley source meter is used for electrical characterization and performance analysis. The study investigates system efficiency, beam propagation characteristics, and conversion performance, providing insights into the feasibility and optimization for practical applications.