Improvements to the iPad's LED backlighting will allow Apple to create a thinner iPad 5, according to NPD DisplaySearch's Paul Semenza.

"It's likely that part of the thinner/lighter design will be reducing the size of the LED backlight, partly by making the display more efficient and partly by using more efficient LEDs," said Paul Semenza, an analyst at NPD DisplaySearch, in an e-mail to CNET.

The Retina displays of the third and fourth generation iPads required a dual-LED backlight along with a bigger battery, which caused them to be thicker than the previous iPad 2.

Semenza also pointed out that a shift to a film-based touch sensor might also serve to reduce bulk. The current iPad mini incorporates a DITO film touch panel sensor which contributes to its 7.2mm thickness. He was unsure whether Apple might consider a switch to different display technology, but some reports have suggested that Apple is investigating IGZO panels.