This morning, I wished for a peek inside the workings of Apple’s iPad Smart Cover. Barely hours later, I get an e-mail from iFixit’s Miroslav Djuric, pointing me to iFixit’s teardown. Amazingly, the step-by-step photo essay is even more interesting than I thought it would be. Did you know, for example, that there is something called “magnetic viewing film” that lets you “X-ray” anything with magnets inside?
Before we begin, I’d like to complement iFixit in its choice of color. If you’re going to cut any cover open, it should be that horrible baby-blue one. (I have my eye on the pink one when they finally arrive in Spain.)
The guide starts with a look at the magnets and sleep sensor inside the iPad 2 itself, which iFixit previously disassembled. Along the right side are the magnets which hold the Smart Cover closed. These alternate their polarities, plus-minus-plus-minus. The magnets inside the cover run the other way, making the cover always sit in the right direction.
The other side of the iPad has the super-strong magnets that clamp the cover’s hinge to the frame. These are actually inside the back cover, and are curved to fit the shape of the iPad’s edge, ensuring they get as close as possible to the case on the other side of the aluminum shell.
Then it’s on to the Smart Cover, and the magic that is magnetic viewing film. This is kind of like e-ink. The film sandwiches a mixture of metal flakes and oil between its flexible sheets. In the presence of a magnetic field, the flakes align. Depending on the direction they line up in, they either show a bright reflective side or a dark edge. This makes a picture that is a good approximation of the magnets beneath.
The film shows the magnets inside the cover. On the right side, there is a grid of three columns and five rows (with one magnet “missing” top left), along with the sensor-triggering magnet. This may seem like overkill to hold it shut, but remember these magnets also have to keep the case rolled closed when folded up into a triangular stand (they attach to a steel plate in the far-left panel).
On the other side are six magnets, arrayed long-short-short, short-short-long. If translated into Morse code, this would read “DU.” Apple conspiracy theorists should start work on this right now. The patterns, combined with varying poles, means that the Smart Cover can only be attached the right way.
Finally, a word on the strength of the magnets from iFixit:
We just can’t keep these things off of one another! The iPad 2’s frame magnets made a solid two-inch leap across the table by the time we took the shot. Their attraction for one another is amazing!
iPad 2 Smart Cover Teardown [iFixit]
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