NEW YORK (AP) — New tablet computers from Samsung will feature screens that are richer in color than standard LCDs.These screens, known as AMOLED for active-matrix organic light-emitting diodes, are already found in smartphones made by Samsung and a few other manufacturers. But until now, tablets haven’t used them because larger AMOLED screens are more difficult to produce.Samsung Electronics Co. is trying to change that with its upcoming line of Android tablets, called the Galaxy Tab S. On Thursday, Samsung announced two such models, with screens of 8.4 inches and 10.5 inches, as measured diagonally.The tablets will start selling in the U.S. in July at $400 for the smaller model and $500 for the larger one — the same as comparable iPads. Models with 4G LTE cellular access are expected later in the year.Samsung is the world’s second-largest maker of tablets, behind Apple and its trend-setting iPads.