iPad 2 glass 27% thinner, yet stronger than original iPad?

iPad 2 glass 27% thinner, yet stronger than original iPad?

Perhaps to save weight, the glass screen of the iPad 2 is 27% thinner than the glass screen on the original iPad yet this new test by iFixYouri shows it might be even stronger. Or to quote them:

“That glass was redonkulously strong!”

The increase in strength seems to come from greater flexibility. They performed a number of tests, including drops, without breaking the glass. Video after the break.


Have something to say about this story? Leave a comment! Need help with something else? Ask in our forums!


Senior Editor at iMore and a practicing therapist specializing in stress and anxiety. She speaks everywhere from conferences to corporations, co-host of Vector, Review, and Isometric podcasts, and should be followed on Twitter @Georgia_Dow.

More Posts



← Previously

Real Racing 2 HD for iPad 2 to provide 1080p, full screen video out to TV

Next up →

Apple releases iOS 4.3.1 for iPhone, iPad

Reader comments

iPad 2 glass 27% thinner, yet stronger than original iPad?


Watching him flex it with bare hands made me wince. I could just see the glass shards piercing his radial artery and making a mess of the situation.

This is not a strength test, it's a flexibility test, and it makes perfect sense that a thinner screen is more flexible.

This is nice and everything, but what does it prove? That the glass will be the only thing you won't have to replace when you drop your iPad? Weight the glass to the same weight as the iPad, then drop it on a corner and see what you get. THAT would be a real world test.

Damn, that's impressive. Remember guys, this is GLASS. I'm not used to seeing glass flex that much and not break.
That said, I've already seen a handful of stories on Macrumors from iPad 2 owners who have already cracked their glass fairly easily.
So as always, it all depends on how the device hits the ground after a drop.

Unfortunately this was an errored test of this glass. Bending or flexing the glass in this instance, because the glass, without researching fully is either chemically toughened (which I think it has), heat treated but is, because of the way it broke in the video a laminated glass it means that this glass has a high flexibility. Simply by reducing the thickness it becomes more flexible, it is the nature of glass.
Making glass thinner just allows a little more flexing but the tensile strength of glass is determined by the toughening method use, whether it more than one sheet laminated together (though it will remain as a sheet but will crack).
The weakest part of any toughened glass is the corners, this is the highest stress, especially in heat treated glass. Ask anyone that has broken the glass on the Iphone most images of breakages have the break starting in the corner or if it starts anywhere else it will end up the break ending in a corner.
The glass in the rear of your vehicle has over 2 inches of flex in it and that's 3mmm 4mm or 5mm thick depending on the specification of the manufacturer. This same glass has very likely also been placed under 4 to 8 tonnes of compression when a poly-urethane decorative trim was injection molded to the glass. I've actually seen glass where it has been manually pulled from a mold at an automotive plant in the UK where the glass flexed 8 inches before it failed where the releasing agent was not applied correctly and the PU was sticking to the mold.
I was in the glass industry, designing for home, industrial and automotive processes for over 10 years and glass is far stronger than most people think.
Look at the strength of the Corningware dishware range, they are inherently strong glassware items but while Corning Corporation say that their glass dishware is unbreakable it can and will break under the correct situation.
These guys have chosen a flawed method of demonstrating strength. Tensile strength is not a true gauge of strength for this type of glass.

If the screen was made of paper, this "strength" test would reveal that it was indestructible. A polycarbonate screen would flex much more than this, and yet could anyone argue that a screen that scratches just by wiping a clean cloth over it was "stronger" than glass?

I can't view the video at work, but I assume from what you guys are saying that they didn't do any impact tests. We saw all sorts of flex tests from the i4, all of which were pointless when it's stuck on a case that DOESN'T flex. It's the impact tests we'll need to see.