NTT DoCoMo's president Ryuji Yamada displays a new smartphone for elderly people, the Raku-Raku smartphone, at an unveiling ceremony in Tokyo.

Leading Japanese mobile operator NTT DoCoMo on Wednesday unveiled its first smart phone specially designed for elderly users, as the company bids to tap into an ageing consumer population.

The touch-screen handset, to go on sale by August, will show large fonts and icons with simplified steps for emails and taking pictures, it said.

"The handsets display large buttons and fonts to show the menu that is easy to understand," the firm said.

Japan's population is ageing because of a low birth rate.