Once Established and Commercialized, Murata's Unique Technology Will Bring About Innovation in Wireless Power Transmission

Increased customer awareness is prompting the use of wireless power technology. Murata has successfully developed a concept unique among the several solutions the market has seen to date. Featuring ease of introduction, a wide charging area, and low heat generation, this unique technology is now finding increasing use among customers. Murata is now ready to move further ahead of the competition with its capacitive coupling technology.
Satoshi Ishino Director, New Business Development Group, Technology & Business Development Unit


After joining Murata Manufacturing in 1983, Ishino was responsible for trimmer capacitor and variable resistor technologies in the Circuit Module Dept. He worked for Murata's American subsidiary between 1987 and 1995. From 1995 to 2008, he worked on ceramic multilayer products and RF modules, before being assigned to his current position in 2008 to create new businesses. When off work, he enjoys walking at scenic locations and in traditional cultural districts.

Wireless power has been attracting increasing attention as a solution that makes mobile phones, smartphones, and tablet terminals even more convenient.
This technology makes it possible to transmit electric power to rechargeable batteries without the need for cables.
Energy transfer represents a completely new terrain for Murata.
Our engineers have come up with an innovative module, which has now been commercialized.

Murata Wireless Power Transmission Module Hits the General Market

I have been working on the development of a wireless power transmission module as part of Murata's energy business. Designed to recharge mobile phones and tablet terminals in a contactless fashion, the Murata wireless power transmission module can transfer power once a device is placed within a defined area around the module.

It features ease of introduction, a wide charging area, and low heat generation in the wireless power transmitter. We had aimed to commercialize this technology for some time before Hitachi Maxell, Ltd. introduced a Murata module into the "AIR VOLTAGE for iPad2*" in November 2011.

Wireless power transmission modules can be used in a variety of equipment, making recharging easy at home, work, and in public places.

* iPad is a registered trademark of Apple Inc.

Different Contactless Power Transmission Concepts

Three major technologies are being used to achieve wireless power transmission. The first, electromagnetic induction, transmits power using induced magnetic flux between transmitter and receiver. When the coil in the transmitter is energized, it generates a magnetic flux, which in turn generates an electric current in the receiver coil. A drawback is that any misalignment of the coils reduces transmission efficiency. Another disadvantage is that the coils in both the transmitter and receiver require relatively large space. This technology, which Murata, among others, worked on for a long time, represents a relatively old approach to contactless power transmission.

The second, capacitive coupling technology, is employed in the new wireless module from Murata. Electrodes are installed in both transmitter and receiver. As both electrodes are brought close to each other, an electric field is generated between them that is used to transmit energy. Compared with electromagnetic induction, this technology provides higher transmission efficiency and alleviates the need for precise alignment between the electrodes of the charging pad and the mobile terminal. What's more, one charging pad can be used to recharge two or more terminals. This patented Murata technology was developed in collaboration with a partner.

The third technology, magnetic field resonance, is based on semiconductor technology. Radio wave technology is a further alternative that converts radio waves received by an antenna into electric power. We have suspended the development of this technology because it doesn't allow us to take advantage of Murata's strengths.

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