TOKYO (AP) - Japanese scientists say they have used cutting-edge technology to create a noodle bowl so small it can be seen only through a microscope.

Mechanical engineering professor Masayuki Nakao said Thursday he and his students at the University of Tokyo used a carbon-based material to produce a noodle bowl with a diameter 1/25,000 of an inch in a project aimed at developing nanotube-processing technology.

The Japanese-style ramen bowl was carved out of microscopic nanotubes, Nakao said.

Nanotubes are tube-shaped pieces of carbon, measuring about one-ten-thousandth of the thickness of a human hair.

Carbon nanotubes are being explored for a wide range of uses in electronics and medicine because their structure endows them with powerful physical properties such as a strength greater than steel.

The ramen bowl experiment included a string of "noodles" that measured one-12,500th of an inch in length, with a thickness of one-1.25 millionth of an inch.

"We believe it's the world's smallest ramen bowl, with the smallest portion of noodles inside, though they are not edible," Nakao said.

The hardest part was to keep the noodles from rising upright from the bowl "like alfalfa sprouts," he said. "The achievement was mostly for fun."

The microscopic bowl was first created in December 2006, but revealed only Thursday after it was entered for a microphotography competition last week.