updated 12:50 pm EST, Sun February 2, 2014
Patent outlines manufacturing and growing process
Along with the patent awarded for the ejectable component assembly last week, the United States Patent & Trademark Office also granted Apple a patent for manufacturing sapphire windows, which had originally been submitted in July 2012. The patent gives credence to the reports of all-sapphire glass displays used on the new iPhone prototypes, as well as the company pushing to open a US sapphire manufacturing plant in Arizona this year.
The patent, application 20140030443, refers to the shaping and polishing process of creating the windows with laser, operating near 50 watts and into the infrared spectrum, via melting or evaporating material to cut it away. The application notes that the sapphire may even be polished ahead of time, as the laser cutting will not disturb the surface. It also describes the process of applying decoration to a polished wafer of sapphire, using inks that are applied to the intended surface and used as an outline for the cutting process.
Growing methods for the artificial sapphires is included in the patent, giving Apple a strong manufacturing edge in the process, which may lead in the reduction in dependence on outside materials. Shortages for screen materials, such as Corning's Gorilla Glass, has led to a hold up in production for device manufacturers in the past.
The patent will allow Apple to step away from the use of Gorilla Glass in the near future. The company is currently already using sapphire glass on touch sensors and back side cameras in the iPhone line. The artificially-made sapphire is favored because it offers a superior resistance to scratches and overall durability, even more so than Gorilla Glass. Speaking with Techcrunch in November, Mathew Hall, the director of the Center for Advance Ceramic Technology at Alfred University stated that the "toughness of sapphire should be around four times greater than Gorilla Glass -- about 3 Mpa-m0.5 versus 0.7 MPa-m0.5, respectively." Weight and cost differences will greatly depend on the thickness of the sapphire used in future devices.
Information on the patent filing, application 20140030443, can be found at the USPTO website.