Why the Apple Watch’s Screen Is Its Most Overlooked Feature
With Apple’s highly anticipated and characteristically secret Apple Watch finally revealed to the public, the smartwatch’s features have already been extensively discussed and analyzed. But perhaps the most overlooked advance that Apple introduced with the Apple Watch is its screen: a sapphire display that’s actually flexible and force-sensitive. With those features, the Apple Watch’s screen is set to usher in important innovations in manufacturing and user interface design.
In the months leading up to the launch of the iPhone 6 and the Apple Watch, it was rumored that one or more new iPhone models would feature a display made out of scratch-resistant sapphire glass. They turned out to be wrong, but Apple announced that the Apple Watch comes equipped with a sapphire Retina display, Apple’s first foray into using the expensive material to cover the entire screen of a device. Live Science explains that the synthetic sapphire used for the screen of the Apple Watch is the crystallized form of aluminum oxide, which boasts a crystal clear transparency that makes it ideal for screens.
Vox reports that to make a sapphire screen, aluminum oxide is ground to a powder, then heated to more than 3,600 degrees Fahrenheit, and processed into sheets. Sapphire is a totally clear but remarkably tough material — second only to diamond in hardness — and will likely enable Apple Watch wearers to drop the watch or bump their wrist against things without damaging the device. That would likely not be the case if Apple used its usual Corning Gorilla Glass.
Gorilla Glass is a chemically-infused glass that is more durable than normal glass, but significantly less durable than sapphire. Sapphire is more complex and expensive to manufacture than chemically-infused glass, and it’s frequently been used in expensive watches. While sapphire can be brittle and prone to cracking if processed incorrectly, Apple has likely taken measures to make sure that that doesn’t happen.
However, it’s worth noting that the Apple Watches in the Sport collection don’t feature sapphire, and instead use “strengthened Ion-X glass,” which, Apple explains, along with a new aluminum alloy used for the case, makes the Spot watch up to 30 percent lighter in weight than the stainless steel models. The Ion-X glass is “an aluminosilicate glass that’s especially resistant to scratches and impact,” and is “fortified at the molecular level through ion exchange, with smaller ions being replaced by larger ones to create a surface layer far tougher than ordinary glass.” As the technology section of the Apple Watch website explains:
“A Retina display is the primary surface for every interaction with Apple Watch … On most Apple Watch models, the display is laminated to a machined and polished single crystal of sapphire. Next to diamond, it’s the hardest transparent material. On watches in the Sport collection, protection is provided by strengthened Ion-X glass.”
The high-quality and energy-efficient Retina display also features a high pixel density, which Apple promises will make text and numbers easy to read, and make even finely detailed images and graphics sharp — even on the small screen of a wrist-sized device.
There are still a few unsolved mysteries around the Apple Watch’s display, and one of those is related to the fact that its screen is actually flexible. As MIT Technology Review’s Kevin Bullis reports, the watch’s screen is a flexible display, which is laminated onto a stiff pane to avoid the damage caused by constant bending. But if the screen can’t actually bend or wrap around your wrist, then why did Apple make it flexible? Possibly to allow a slight curve at the edge of the display, or to make the screen thinner and the profile sleeker than those of other smartwatches.
But more importantly, Bullis explains that the Apple Watch’s screen is almost certainly an OLED display, where each pixel glows on its own instead of relying on the backlight needed to illuminate LCD pixels. (Up until now, all of Apple’s “Retina” displays were LCDs, though the term “Retina” doesn’t have a technical meaning attached. The company simply uses the term to denote a high-density display.) OLED displays are thinner and lighter than LCDs, can be brighter than LCDs, and perform better in direct sunlight.
Manufacturers have been able to make flexible OLEDs for years, but the fact that the technology is beginning to appear in commercial devices means that manufacturing advances to make OLED displays durable to develop electronics, touch components, and even batteries that can endure being bent are already underway. That could bring fully flexible devices within the space of just a few years.
Force-Sensitive Touchscreen and Force Touch
The biggest advance Apple packed into the Apple Watch’s small screen is the pressure-sensitive touchscreen’s ability to distinguish between various types of presses. That enables the user interface to be much more complex and capable than such a small screen would otherwise allow. The ability to differentiate between gestures could enable the apps built for the device to incorporate a set of context-aware commands, accessible via a new gesture called a Force Touch instead of via buttons and menus constantly available in the visible user interface.
Wired’s Joseph Flaherty notes that the force-sensitive screen will appear only on the Apple Watch to start. But if it’s successful, it could represent a major step for touch computing. Flaherty characterizes the “press and hold” mode of input as a return, of sorts, of the “right click” that made desktop software like word processors into powerful tools, with easy access to a wealth of functionality. The Force Touch mechanism should let Apple pack more functionality into the small screen of the Apple Watch, but notes that bringing the same feature to larger screens could replace obtrusive user interface features with context-specific press menus.
That would represent a major improvement for full-featured apps — Gmail, Photoshop, or Excel, for example — as designers try to pack all of the desktop interface’s features onto an iPhone screen, and “hamburger buttons” appear in every app where users want more functionality than can otherwise fit in such a small space. Pressing and holding a word in a text editor or a photo in the Photos app could enable users to access options they’d otherwise have to hunt through menus to find.
A 2013 piece by The Wall Street Journal on user interface features commonly found in apps explained not only the hamburger button — the icon of three horizontal lines that supposedly represent a hamburger bun and its contents — but other mechanisms including the “swipe,” the “pull to refresh,” and the “edge gesture” (swiping from or off the edge of the screen). Each of those user interface features represents a step that developers and designers have taken to make apps and mobile operating systems easier to use, more feature-rich, and more able to handle a complex variety of user input.
The user interface of the Apple Watch and its addition of Force Touch is a prime example of how that principle is moving to the future. A touchscreen that can differentiate between a tap and a press isn’t the only method of input. The Digital Crown allows users to navigate and zoom by spinning, or to return home by pressing. Or users can use voice control to dictate commands to Siri, send messages, or ask for directions. Even notifications are getting smarter, with the Apple Watch employing haptic feedback to alert wearers to incoming calls and texts. The watch can even sense when the user raises his or her wrist so that it can activate the screen at the appropriate time.