Japanese train commuters who don't want to reach conspicuously into their bags or pockets to start their iPods will soon be able to do it more subtly -- by simply clenching their teeth.

Japanese researchers have developed head gear that uses infrared sensors and a microcomputer to let people operate music players by clenching their teeth.

The computer receives a command when the user clenches his or her teeth for about one second -- which differentiates the action from other activities such as chewing gum and talking.

The research team at state-run Osaka University hopes to put the device to commercial use for music players and believes it can eventually be adapted to run cellphones, wheelchairs and other products.

"You are able to operate the devices without using your hands," said Fumio Miyazaki, an engineering science professor who heads the laboratory working on the project.

"You would be able to listen to music hands-free or operate your cellphone in a crowded train. Handicapped people would also be able to move wheelchairs," he told reporters.

Kazuhiro Taniguchi, who is playing a leading role in the research, said the system can be used by anybody who can chew food with their teeth -- real or artificial.

"I just thought it's inconvenient" to have to use your hands to switch on iPods or phones, especially on packed trains, Taniguchi said.

In the laboratory, grinding right teeth can play and halt music on an iPod while clenching left teeth makes it skip to the next track, he said.

The system could also allow users to flip through pages of a PowerPoint demonstration, allowing the presenter to gesture freely by clenching teeth instead of pressing buttons.

(AP) 乘火車通勤的日本人如果覺得把手伸進包里或口袋里開iPod太費勁，那么這一問題很快就能解決了——你只需咬咬牙就能啟動iPod。

日本研究人員近日開發出一種內置紅外線傳感器和微型計算機的頭套，通過這種裝置，人們只需咬緊牙就能啟動音樂播放器。

當人們咬緊牙約一秒鐘時，微型計算機就能接收到一個指令。而這里所說的咬緊牙與嚼口香糖和說話等活動是不同的。

大阪國立大學的研究小組希望能將這一裝置投入商用，用于音樂播放器，并相信這一裝置經“改造”后，最終還能用于手機、輪椅和其它產品。

工程學教授、該項目的實驗室工作負責人宮崎文雄說：“你不用手就能啟動播放器?！?/P>

“以后在擁擠的火車上聽音樂、擺弄手機，就不用手了。殘疾人也能自己移動輪椅了。”

該研究的主要負責人谷口一浩說，只要能用牙（真牙假牙都可以）咀嚼食物的人就可以使用這一系統。

他說：“我只是覺得用手操作iPod或手機不方便，尤其是在擁擠的火車上?！?/P>

據他介紹，在實驗室所做的實驗中，咬緊右邊的牙齒能夠啟動和停止iPod，咬左邊的牙則能使播放器跳至下一個節目。

人們還能通過這一系統翻動PowerPoint演示頁，這樣演示者就可以騰出雙手自由地做手勢了，因為他們只需要咬咬牙，不用再按鍵了。