The Apple Retina display is a backlit LCD (liquid crystal display) that provides resolution levels of 220 to 326 pixels per inch. Retina displays are included in recent models of Apple's mobile devices and the MacBook Pro notebook computer.
The Retina display includes an ambient light sensor that allows for automatic screen brightness adjustment for optimum viewing in environments ranging from darkness to sunlight. It has received mostly positive reviews, particularly the one in the third-generation iPad released in March 2012. That device's screen has 2048 by 1536 pixels with a 9.7-inch diagonal measure, doubling the resolution for height and width from that of the iPad 2, whose screen had 1024 by 768 pixels with a 9.7-inch diagonal measure.
Apple has registered the name "Retina" as a trademark, although the displays are manufactured by LG or Samsung, depending on the particular device.