SAN FRANCISCO -- Apple Inc. on Monday said it's introducing a laptop with a super-high resolution "Retina" display, setting a new standard for screen sharpness.

The new MacBook Pro will have a 15-inch screen and four times the resolution of previous models, Apple executive Phil Schiller told developers at a conference in San Francisco on Monday.

Apple already uses "Retina" displays -- with individual pixels too small to be distinguished by the naked eye -- in its latest iPhones and iPads.

On the phones and tablets, the Retina display is a standard feature. On the MacBook, it's an expensive upgrade. The new MacBook will cost $2199 and up, $400 more than the non-Retina MacBook with the same-sized screen.

The new MacBook is part of a general revamp of Apple's personal computer line announced Monday.

Apple also said the new version of its Mac operating system, Mountain Lion, will go on sale next month for $20. The update brings features from Apple's phone and tablet software, like the iMessage texting application, to the Mac.

Mountain Lion will also bring dictation to Macs. Users will be able to input text by talking to the computer, in any program. This is already a feature of Microsoft Corp.'s competing Windows software.