America Online Inc., the world's largest on-line service provider with 8 million members, announced Mar. 25 that it will launch a Japanese-language Internet service on April 15.

In cooperation with the Nihon Keizai Shimbun and Mitsui & Co., AOL Japan intends to provide an on-line service similar to the popular one its parent company runs in the United States. Prospective users will be offered 10 hours of free usage for one month. After the trial period ends, AOL will charge a monthly fee of 980 yen per 3 hours, with each additional hour requiring 480 yen. The company also says that it will charge no entry fees or surcharges on the content it provides.

AOL plans to set up 34 access sites nationwide, which will cover over two thirds of the population within their local calling area, according to company officials.