The current industry standard for display protection is alkali-aluminosilicate, or GorillaGlass. Compared to the chemically treated hardened plastic and lime glass that it replaced, there is arguably no better solution. For a few dollars you get superior protection, less distortion and an opacity that won't increase due to excess heat over time. No one would buy a $300 on-contract device with a lens cover made of plastic, and you would be lucky to find someone who would take one for free. Knowing that in 6 months your device would begin to yellow and scratches from even the most careful handling would distort the view, paying a premium for GorillaGlass is a no-brainer. It's a value. Corning has also experimented with sapphire, but due to its manufacturing costs, production time to market and overall cost to the consumer, they made the decision that the consumer wouldn't realize its value.
Then something changed. Someone decided that it was possible to scale a sapphire production operation to a level that could meet Apple's supply chain management expectations for handset sales. That decision had to be made with the understanding that at the time just 250 pounds of sapphire took 2 weeks to grow. Glass can be made right now for as long you want it. This person had to also understand that the mechanical process to cut sapphire couldn't produce a viable solution. That means someone had enough vision to believe that Apple was capable of changing an industry standard....again.
What would that take? Changes in the production process, improvements in manufacturing technology and the discipline to maintain the supply chain management needed to meet consumer demand. One last thing, we can't forget supply exclusivity. Apple will do what it takes to achieve supply chain dominance. They will buy up all the NAND flash, or buy all the lasers that make tiny holes in aluminum. They even buy assembly operations exclusivity from Foxconn in China. In the case of sapphire, they could buy everything there was, but still needed to invent the rest.All of this for screen protectors? Corning, the undisputed market leader in display protection having documented success not only in consumer but military applications, chose not to pursue sapphire. Not even after testing it. 578 million bucks, and that was just to get started. Who knows how much they blew since then on at least 2 patented inventions, resources to invent new manufacturing technology, research and development behind that and then the means to build that new technology and deploy it? For display protectors? What does a computer company know about making a phone...display cover? To our friends in Cupertino, $578+ million might not even get missed in a $160 billion war chest, but would they invest so heavily into something that was just a little better? Or perhaps simply novel? Apple has spent ridiculous amounts of money for things most people don't even notice, like the green LEDs on the MacBook Air next to the camera and on the Magic Trackpad and Wireless Keyboard. The lasers needed to do that cost $250,000 each and Apple bought all of them, hundreds of machines just to make holes in your computer that you can't even see until the light behind them turns on. Until a couple of days ago, no one had seen the i6 display cover. That's when Marquess Brownlee released his experience with a factory example of the 4.7 inch version. I don't think anyone can watch it and not think why hasn't this been used before? 3 reasons why sapphire is better than mineral glass on a handset with a touch sensitive display are apparent. It's harder. You can easily see the punishment it takes when he was stabbing it with the knife. In fact, it's the second hardest material there is which is why diamond saws were the tool used to cut them, at least they were before Apple changed that. It's more resistant to scratching. It's flexible, obviously. But the clarity that is shown is absolutely stunning. Defense systems that use optical sensors to detect and track are protected with sapphire. It has a high optical transmission of light over a broad spectrum of frequencies, and it's very durable. That's why, to protect its optical sensors, Apple put them on the camera and the biometric sensor. The predicted increase in response and accuracy to touch won't be known until someone gets an entire handset. Apple must have also been very successful with its sapphire laser cutter, and heat exchanger. The laser would provide the ability to cut the lens thin enough, provide chamfering and increase yield. The heat exchanger, used in the growing of the crystal, would decrease the crystal growth time requirement. Finally, Apple's patent on embedding sapphire into controls and markings implies that more than just the display will be covered in sapphire. The sleep/wake button, volume buttons and home button are probably going to be illuminated sapphire. You can expect the etching on the back panel of the handset to be gone, replaced by an ion implantation somewhere underneath a sapphire panel that will show the required marking instead. One of the complaints you hear about the any iPhone, is that is looks just like the last iPhone. It's subtle changes just don't seem enough for many. New materials and a larger form factor on the iPhone 6 could give them what they are asking for.