CORNING, N.Y., Aug 7 -- In an effort to keep up with market demand for its precision flat glass, Corning Inc. will invest $250 million to increase production of its liquid crystal display glass, the company said. The LCDs are used for computers, Internet and communications tools. This latest investment makes more than $500 million the company has put into expansion in less than a year, and will triple its worldwide capacity by the end of 2001, the company said. The capital expenditure on active matrix LCDs will be used to increase capacity at Corning's facilities in Harrodsburg, Kentucky; Shizuoka, Japan; and in Tainan, Taiwan.