What Is Wireless Charging?

Wireless charging technology (English: Wireless charging technology) originates from wireless energy transmission technology, and can be divided into two ways: low-power wireless charging and high-power wireless charging.

1890, physicist and electrical engineer

There are five mainstream wireless charging standards: Qi standard , Power Matters Alliance (

The wireless charging industry chain is divided into two parts: receiving and transmitting. The upstream and downstream industrial chains at the receiving end are divided into chips, magnetic materials, transmission coils, module manufacturing, and system integration. The transmitting end is divided into: chip, coil module, scheme design.

The receiver chip and system integration design link has high technical barriers and high profits (approximately 30% of the profits of the wireless charging industry chain each). The main customers are mobile phone terminals. The development status is very similar to the fingerprint identification three years ago. Only IDT has experience in shipping. Broadcom is an official customization for Apple. Others, including TI and Qualcomm, have failed to seize the first wave of opportunities in the industry. Can enter the supply chain of any mobile phone manufacturer ^[4]

According to the World Wide Web report, the latest "iPhone" that Apple is scheduled to release in 2017 may use a wireless charging module. Some people say that the radiation of ordinary mobile phones must be protected, let alone wireless charging mobile phones! Some people worry that the radiation generated by wireless charging will cause cancer? To this end, the reporter interviewed Zhou Hongzhi, associate professor of the School of Applied Mathematics and Science, Beijing University of Technology ^[5] .

1. What's the matter of wirelessly charging your phone?

The principle of wireless charging technology is actually very simple. Zhou Hongzhi said, "The basic principle of the so-called wireless charging technology is the same as that of a transformer. As an example, a mobile phone has a magnetic core in a charger, and a coil is wound on the outside, which can convert electricity into an electromagnetic field, and the electromagnetic field can propagate in space. At the same time, the mobile phone also has a corresponding receiving coil. After the electromagnetic field emitted by the device is processed by a certain circuit, the mobile phone can be charged ^[5] . "

2. Can the radiation generated by wireless charging of mobile phones cause cancer?

Zhou Hongzhi said, "Wireless charging of mobile phones will generate some radiation, but under the premise of quality assurance and correct use, this radiation will have little harm to the human body, and will not cause cancer. On the one hand, when wireless charging, the magnetic field It is closed and has little external radiation; on the other hand, as long as it is a national 3C certified product, it will undergo strict inspection, and the radiation it produces must also meet certain standards, which will not cause harm to humans.

3. Will the radiation generated by various electronic products be superimposed?

With the development of science and technology, people are more and more exposed to electronic products: computers, mobile phones, tablets and so on. Some people worry that there will be radiation in electronic products? Will these radiations add up and produce the effect of "1 + 1 = 2" or even "1 + 1> 2"?

Zhou Hongzhi said, "Electronic products have radiation, but as long as they meet the national 3C certification standards, they will not cause harm to the human body. As for radiation superposition, it must meet very strict conditions. In daily life, '1 + 1 = 2' Or there is almost no '1 + 1> 2'. The radiation generated by various electronic products will interfere with each other, but they will not overlap each other, and in many cases they will even cancel each other out. For example, many people throw at the lake at the same time. Stones, each stone will form a water wave, but these water waves will not be superimposed into huge waves, and it is also true that radiation does not superimpose. ^[5]

4. Why hasn't the technology for wireless charging of mobile phones spread?

The technology of wireless charging for mobile phones has been expected, but it has not been popularized yet. Is it because its cost is too high, or is it technically difficult to achieve?

Zhou Hongzhi said, "Technically speaking, wireless charging of mobile phones can be achieved, and the cost is not high. The reason why this technology has not been popularized is mainly the issue of standards and requirements, such as which specifications should be used for the charger. How to close the magnetic field, etc., these standards have not yet been officially released. "However, Zhou Hongzhi said that once the relevant standards are officially released, the technology for wireless charging of mobile phones will soon be popular ^[5] .