Over a million developers have joined DZone.
{{announcement.body}}
{{announcement.title}}

How the iPad 2 Smart Cover performs its magic

DZone's Guide to

How the iPad 2 Smart Cover performs its magic

· Mobile Zone
Free Resource

Discover how to focus on operators for Reactive Programming and how they are essential to react to data in your application.  Brought to you in partnership with Wakanda

iFixit has figured out how Apple’s Smart Cover for the iPad 2 works. This blog post summarizes the findings.
The Smart Cover folded as a keyboard stand. [Source: Apple]
The Smart Cover is one of the iPad’s most important features. It has several intriguing characteristics:
  • When you magnetically attach the Cover hinge to the iPad, it automatically “finds” the right place.
  • When you open the cover, the iPad is immediately switched on. There is no button to press and no on-screen widget to swipe.
  • The Cover also snaps closed and stays attached to the surface of the iPad. Upon closing, the iPad goes to sleep.
  • You can fold the Cover behind the iPad to prop it up slightly for typing or to position it vertically for video viewing.
iFixit has disected the Cover and the iPad to figure out how they work together. Here is a summary:
  • iPad
    • Left side (on the back): Magnets to attach the hinge.
    • Right side: Magnets to keep the Cover closed. These magnets are also needed to offset the reduction of rigidity caused by the segments.
    • A sensor in the bezel (on the right) registers whether a magnet is currently attached. Changes lead to the iPad going to sleep or waking up. There is a smaller magnet in the Cover dedicated to this purpose.
  • Smart Cover
    • Hinge: The hinge magnets alternate between positive and negative polarity. Those polarities are matched by the iPad magnets and are responsible for the Cover automatically attaching at the right place. The hinge actually consists of two hinges, to enable folding.
    • Left side: A metal plate works with the magnets at the right side to keep things in place when the Cover is folded up.
    • Right side: In addition to magnets assisting the right side of the iPad in keeping the Cover closed, there are several magnets with the sole purpose of increasing attachment strength during folding. The same effect could have been achieved by making the left side magnetic, but that might have adversely affected the iPad.

The Cover contains a metal plate on the left side and 14 large magnets on the right side. Of these, 4 attach to the iPad, the other 10 are only used to hold the metal plate during folding. An extra small magnet (top left corner of the yellow rectangle) is used for switching the iPad on or off. [Source: iFixit]
I am surprised that Apple has actually built magnets into the iPad, but apparently that was necessary to make the attachment strong enough. It just goes to show how iPad and Cover have been designed in tandem.

Further reading:

Learn how divergent branches can appear in your repository and how to better understand why they are called “branches".  Brought to you in partnership with Wakanda

Topics:

Published at DZone with permission of Axel Rauschmayer, DZone MVB. See the original article here.

Opinions expressed by DZone contributors are their own.

The best of DZone straight to your inbox.

SEE AN EXAMPLE
Please provide a valid email address.

Thanks for subscribing!

Awesome! Check your inbox to verify your email so you can start receiving the latest in tech news and resources.
Subscribe

{{ parent.title || parent.header.title}}

{{ parent.tldr }}

{{ parent.urlSource.name }}