Display in iPhone 5: What to expect?
Most other phone manufacturers have already released touch-based smartphones with display size up to 4.5". Some of these large phone even rival the "Retina Display" with a 720 HD size: for example Sharp's 'Aquos Phone 102SH' boasts a 4.5" glasses-free 3D display with a 1280 x 720 resolution (326 ppi), while Hitachi has just demoed another 4.5-inch HD-ready IPS LCD panel based on a more affordable a-Si (amorphous silicon) TFT technology compared to the more expensive and more complicated low temperature polysilicon or LTPS used in the iPhone 4's display (see our blog on "Retina Display" in the next iPad? Part II: Technological Constraints).
Although Steve Jobs has dismissed the idea of larger phone ("no one's going to buy a phone you can't get your hand around it") at a press conference last year, to stay competitive Apple has to deliver an iPhone with a larger display while maintaining the same quality as in the "Retina Display". However this could be done without increasing the physical size of the phone as illustrated below:
A 4" display can perfectly fit inside the iPhone 4 enclosure by slightly reducing the space around the display, a solution that would probably please Steve Jobs! It is worth noting that the vertical reduction from 0.8" to 0.6" (i.e. 25%) is not very challenging since 0.6" is already the space found between the display in the top and bottom borders of the last generation of the iPod touch which also incorporates front and back cameras. The horizontal reduction from 0.18" to 0.06" (i.e. 67%) appears much more challenging as it would require a much thinner bezel to support this edge-to-edge display technology, but not impossible given Apple's involvement in the development of advanced manufacturing processes. Then one can reasonably expect that the iPhone 5 will sport at least a 4" LCD display, a 25% increase in surface area compared to the previous generations.
What resolution?
All iPhones released so far have a 3:2 size ratio and there is no reason to believe that this will change: 480 x 320 at 165 ppi for the 3 first generations of iPhones and 960 x 640 at 326 ppi for the latest generation. Assuming the iPhone 5 keeps the same 3:2 ratio, the various possibilities are summarized in the table below:
| Product | Resolution | Specification | Size (inches) | Density (ppi) |
|---|---|---|---|---|
| iPhone 3GS/iPod touch 3G | 480 x 320 | HVGA | 3.5 | 165 |
| iPhone 4/iPod touch 4G/iPhone 4S? | 960 x 640 | WSVGA | 3.5 | 326 |
| iPhone 4S? | 1080 x 720 | HD720 | 3.5 | 371 |
| iPhone 5? | 1080 x 720 | HD720 | 4.0 | 325 |
| iPhone 5? | 1080 x 720 | HD720 | 4.3 | 302 |
| iPhone 5? | 1080 x 720 | HD720 | 4.5 | 288 |
| iPhone 5? | 1080 x 720 | HD720 | 5.0 | 260 |
| iPhone 5? | 1440 x 960 | WSXGA | 5.0 | 346 |
The closest configuration to the "Retina Display" pixel density is the HD720 resolution (1080 x 720) with a display diagonal of 4". As suggested above, such a display would fit well inside the standard enclosure of the iPhone or iPod touch by slightly reducing the space below and above an edge-to-edge display. Consequently we think that a new iPhone with an improved display would certainly boast a 4" HD720 LCD panel. We will find out this coming Tuesday...
October 4, 2011 - Update
Unsurprisingly, Apple only announced the iPhone 4S with the same "Retina Display" as the previous generation. We will probably have to wait until next year to see display improvements in the iOS devices...
William H.A. Beaudot, PhD
Founder & Chief Scientist
KYBERVISION Consulting, R&D
