Bone conduction is a method to transmit sound to the auditory apparatus using bone vibration in the skull. This method features greater loudness sensitivity so that phone users can hear the speaker’s sound more easily in noisy surroundings. According to the company, it is the world’s first cellular phone using bone conduction.

Three TU-KA group companies will launch the “TS41,” a cellular phone that has a sonic speaker using bone conduction, at the end of December 2003.

The handset was developed by Sanyo Electric Co, Ltd. It is a folding-type cellular phone weighing 98g that accommodates a normal speaker as well as a sonic speaker. Continuous talk time lasts about 140 minutes when using a normal speaker and about 130 minutes using the sonic speaker. Standby time is about 400 hours.

Products using bone conduction, such as hearing aids and cordless phones, already are on the market.
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