“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.
He said he also expects other modifications to reduce thickness. “The other significant change that we feel is likely is a shift to a film-based touch sensor,” Semenza said.
While it might seem obvious that successive models of new tech get slimmer and smaller, the iPad 3 and 4 were actually thicker than the iPad 2 due to the additional requirements of supporting the Retina display. The iPad 5 is also rumored to be copying the narrow-edged bezel design of the iPad Mini.