Nintendo of America introduced Virtual Boy today, a 32-bit home video-game system that it says includes three-dimensional effects. “Virtual Boy will take video- game players to a completely new dimension in gaming,” Peter Main, Nintendo’s executive vice president of marketing, said, adding that the American unit of the Nintendo Company of Japan expects to sell more than 1.5 million hardware units and 2.5 million pieces of software by the end of the year. The new game will have a retail price of $179.95.