updated 11:05 pm EDT, Tue November 1, 2011
Both relate to earlier iPhone models
Two patents granted to Apple yesterday by the US Patent and Trademark Office deal with some of the technologies behind multi-touch as used in iOS devices, and go all the way back to the introduction of the original iPhone. The company won a patent relating to front-end signal compression for touchscreens, as well as one detailing an improved method of crystallizing an indium tin oxide layer on top of transparent conductive material more safely.
The front-end signal compression patent is noted as number 8,049,732, and covers the concept of a transparent touch screen layered on top of a display, able to relay touch events to the host device and thus have the host device act based on the information given it by the touchscreen such as where a touch is located compared to what is on the screen in the area touched. Apple's patent calls for around 15 possible touch events to be tracked simultaneously. Apple engineers Steve Hotelling and Brian Land are listed as the co-inventors.
The second patent relates more to the manufacture of touch panels rather than to what they do. It describes a method that allows indium tin oxide, which is a transparent conductive material, to be heated to a high enough temperature to crystallize, but controls the temperature to protect the substrate the ITO will crystallize onto. The old method would subject the touch panel substrate to be exposed to temperatures over 660 degrees.
Apple's idea is to find a way to heat the substrate to the temperature required for the ITO to crystallize in such a way that the amorphous ITO material absorbs much of the energy during crytallizing, preventing the substrate from being exposed to high temperatures. The proposal includes the idea that various forms of radiation, from electro-magnetic to laser light to microwave radiation or physical vapor deposition (PVD) could be used to get the ITO hot without increasing the temperature of the substrate.
The patent Apple was awarded is number 8,049,862 and lists engineers Lili Huang and John Zhong as the inventors. The application was filed in mid-2008. Both patent awards may strengthen Apple's hand as it continues to defend itself from patent disputes centered around mobile device technologies.