Imagine a ball pen that would remember what it writes, whether sketches or hundreds of pages of text. When I thought of it in May of 2008 I did not know that such a device had already been invented, but realised that most of the elements that would comprise the invention were already there in existing technology. I subsequently learned that a very similar device to what I had in mind had been invented and was being commercialized. This was the EPOS-enabled Digital Pen and USB Flash Drive from Advanced Digital Positioning Technologies (http://www.epos-ps.com).
Unaware of the existence of a comparable device, such as the EPOS-enabled Digital Pen, I thought there must be many ways that the device I had in mind could be realized. To narrow the options, I decided to let the ball be light-permeable. The technical name of the device could be ‘an optical ball pen stylus’. The marketing people might come up with a trendier name like a Stilly: a silly stylus with memory. The descriptions below are my original ideas and are not identical to those implemented in the commercial device.
