The first of those filings discovered by AppleInsider, titled Stylus For Touch Sensitive Devices, depicts a stylus with a conductive tip that may be heated to create a more consistent interaction between the capacitive-sensors in an iPhone or iPad. Such a stylus would include a rechargeable battery which may be recharged through a docking station built into the iOS devices themselves.
In the filing, Apple engineer Douglas Weber noted that heating the stylus tip may be beneficial in offsetting any instability of capacitance due to aging of the stylus itself. He noted that the tip may be heated in a number of ways. For example, a battery powered heating element, a heat sink which transfers the heat from a user's hand to the tip, or through a fluid-based heating element.
Weber added that the heating element may be anything capable of providing a source of heat, such as a "wire made from materials such as a metal or metal alloy, metal bars or wires, wire insulated in steel or brass, ceramics with positive thermal coefficients," or "fluid stored in the same manner as ink is stored in a liquid-ink pen, for example, inside a plastic tube disposed within the body."
Meanwhile, a second filing for a "Communicating Stylus," describes a stylus that includes a position sensing device such as an accelerometer, a tip for writing, a wireless transmitter for sending position data, and a receiver. Apple engineer Aleksandar Pance, who is credited with the invention, said the combination of those components can allow the stylus to enter data into an iPad or iPhone without actually touching the device nor requiring any specialized paper.
"Rather, the stylus is able to enter data into the computing device, corresponding to images or text drawn draw on any surface," he wrote. "Additionally, the stylus can enter the data from a distance, such as from across the room, to the computing device."
This could allow a user to keep their iPhone stored in their pocket and still be able to use the stylus to enter text or drawings into the device. "This makes it easy, for example, in a classroom setting for a user to take handwritten notes and simultaneously create a digital version of those notes," Pance explains. "Additionally, in another embodiment, the stylus allows for the user to write on a whiteboard mounted on a wall and simultaneously display what he has written on a computing device."
While Apple has so far abstained from introducing a stylus for its iOS devices, instead requiring users to interact with the products solely through use of their god-given fingers, rumors have suggested that the company hasn't abandoned the idea completely and is currently looking into a stylus for the iPad in order to make further inroads into the educational market.
For example, one report from back in February of this year cited "a person who works at Apple on the iPad" as saying Apple continues to consider the idea because adding a stylus option to its tablet device may help the company "reach a wider number of children in school."
Its one of the barriers for school kids and college students to purchase an iPad where they want the ability to take notes by hand and draw in class," that person said.
Both of the filings revealed by the United States Patent and Trademark Office on Thursday were filed on January 6th, 2010, shortly before Apple unveiled the first-generation iPad.