But unfortunately, the research in this field has been delayed for a century. A big obstacle of Zui is that the transmission efficiency is too low and dangerous. Electromagnetic radiation is only suitable for transmitting information, not energy. Because radiation has no directionality, energy will be wasted in useless space. Some people imagine using directional electromagnetic radiation, such as laser, but it is not feasible and extremely dangerous.
Professor Xu Shuyuan from the Department of Electronic Engineering of City University of Hong Kong successfully developed a "wireless battery charging platform" a few years ago, which can put a variety of electronic products on a charging platform and automatically charge them through low-frequency electromagnetic fields, without external wires, and the charging time is the same as that of traditional chargers. However, this technology still needs the product to contact the charger, mainly using the principle of near-field electromagnetic coupling.
Researchers at the Massachusetts Institute of Technology have made new progress in wireless power transmission. They lit a 60-watt light bulb "across the ground" with a power supply two meters away. The design of Soglia Qiqi has a distance limit for non-radiative wireless energy transmission, and the smaller the receiver, the shorter the distance. He calculated that an object the size of a laptop can receive wireless energy transmission within a few meters, "so install one in every room." ...