Science Daily August 30, 2022
Researchers in South Korea used an erbium-doped fiber amplifier optical power source with a central wavelength of 1550 nm. and wavelength division multiplexing filter that created a narrowband beam with optical power within the safety limits for free space propagation. They optimized distributed laser charging which enables self-alignment without tracking processes and automatically shifts to a safe low power delivery mode if an object or a person blocks the line of sight. They incorporated a spherical ball lens retroreflector in the receiver unit to facilitate 360-degree transmitter-receiver alignment, which maximized the power transfer efficiency. The system’s overall performance depended on the refractive index of the ball lens. The experimental results showed that a single-channel wireless optical power transfer system could provide an optical power of 400 mW with a channel linewidth of 1 nm over 30 meters. According to the researchers with further development, it could be increased to levels necessary to charge mobile devices. The receiver could be integrated into devices and sensors. This power is sufficient for charging sensors…read more. Open Access TECHNICAL ARTICLEÂ
Schematic of experimental setup for demonstration. PD: photodiode. PV: Photovoltaic. Credit: Optics Express Vol. 30, Issue 19, pp. 33767-33779 (2022)Â