Dr. Raymond Soneira takes a close look at the 9.7-inch IPS TFT LCD on the iPad 2:
As we show in the Comparison Table below the display on the iPad 2 delivers almost identical performance to the impressive iPhone 4 Retina Display. Although the iPad has a higher pixel resolution than the iPhone 4, the screen is much larger so the number of Pixels Per Inch is only 132 ppi compared to the iPhone 4 Retina Display value of 326 ppi. Lower ppi makes the pixels more apparent, an effect called pixelation. The very high ppi is a major marketing feature for the iPhone 4, but itâ€™s actually something of an overkill (and primarily there for App compatibility) because existing anti-aliasing methods can successfully reduce noticeable pixelation at lower resolutions and ppi.
While the iPad 2 has excellent LCD display hardware, there are two significant shortfalls in the OS display software that Apple could â€œeasilyâ€ fix with a software update that would notably improve the already excellent iPad 2 display performance.
The iPad 2 sports an excellent IPS display, but there are two problems with the software though. One is anti-aliasing that negatively impacts sharpness in text and graphics. Dr. Soneira recommends Apple go to sub-pixel anti-aliasing. The second problem is auto brightness that keeps the brightest ambient light sensor value from when it was woken up resulting in display brightness that’s too bright and wastes energy. For the Comparison Table that thoroughly compares the iPad 2 display to the original iPad and the iPhone 4, hop on over to DisplayMate.