The exact original model used by Lenovo is the AUO B156HW01 V.4. This is a 15.6", matte, 1080p panel with wider than average viewing angles.

This display has been measured by notebookcheck.net and anandtech.com and shown to be one of the best laptop displays shipping.

A contrast ratio over 500 is available and this display is able to show over 95% of the colors in the AdobeRGB spectrum. 1080p is a much higher resolution than the basic 1366x768 display, allowing for more work space.

Viewing angle image courtesy of notebookcheck.net