A dispute between two Orange County companies over technology that increases the memory capacity of computer systems has spilled over to the courts, with Santa Ana-based Simple Technology Inc. filing a lawsuit accusing Dense-Pac Microsystems Inc. of Garden Grove of patent infringement. The suit, filed Wednesday in U.S. District Court, accuses Dense-Pac of infringing on Simple Technology's 1996 patent for "stacking" three-dimensional memory products, allowing more memory to be crammed into a smaller space. The suit does not specify a damage amount. "We will not allow our proprietary technology to be used without our permission," said Mark Moshayedi, chief operating officer of Simple Technology. Dense-Pac denied the allegations, noting that its own memory-stacking technology patent had been filed in 1990. "We're evaluating the suit, but we believe it is without merit," said William Stowell, chief financial officer of Dense-Pac.