InPlay Technologies – Under the Hood

The entire team got the opportunity to sit down with InPlay Technologies at CES to catch up on the new technologies. Let’s get this out of the way first. Yes, InPlay Technologies made the troubled FinePoint digitizer. However, a lot has changed since that time – management, engineering, and the manufacturer they use to produce their products. They claim to have addressed the quality control issues that plagued the FinePoint digitizers on the early Gateway models. I hope they have, because the new InPlay Technologies MagicPoint line of digitizers is pretty impressive technically, and I want them to get a chance.

Digital versus Analog Input

The new MagicPoint digitizers use digital signaling based on pulse width modulation (PWM). At its simplest level, Morse code is a type of PWM where the dots and dashes add together to form letters, words, and sentences. InPlay takes PWM a step further to full packet based communication where each packet can convey a variety of information like X-Y coordinates, right click, or even pen tilt angle. By using PWM on a single carrier frequency, InPlay can add features easily through firmware and software. This also means you have an intelligent pen which can be uniquely identified, which could enable me to have a highlighter, ink Pen, and pencil all sitting beside my Tablet PC, with special nibs with a different feel. It could also allow special diagnostic pens to be used at the factory to reprogram the digitizer. The MagicPoint uses a general purpose microcontroller that processes the information and converts to information the drivers understand. This ought to reduce cost.


In contrast, Wacom uses an analog solution where information is conveyed by frequency shift. In analog communication, the pen and digitizer might communicate at 570kHz on hover and 540kHz when the side button is pushed. When the tip is pressed on the screen, the pen communicates in a range of frequencies from 600kHz – 640kHz to indicated the pressure level with which the pen is being pressed. Because of the analog frequency processing, an application specific integrated circuit (ASIC) is required to filter and isolate the intentional pen signal, as well as convert the analog data stream to digital for communication over USB. This custom chip would be unique to the design and only work with a defined set of features, since adding features would require increasing the frequency range or compressing the signal strength so that closer frequencies are used for different purposes. That kind of compression causes the analog filtering task to get harder as you try to differentiate between adjacent signals to determine what the user is requesting. The additional filtering usually requires a change in the ASIC which is expensive and time consuming.

Analog Digitizer


From the hardware standpoint, InPlay has a sleek solution. Most digitizers I have seen in the past add about 3-5mm or more to the screen depth due to the digitizer and electronics. This is due in large part to the custom ASIC required for analog solutions. Specifically with Wacom, most of the Tablet PC digitizers also layer the custom ASIC directly under the digitizer film, so that you have the thickness of the film plus the thickness of the ASIC added together. This depth is actually noticeable – and in some cases objectionable. Can you imagine the MacBook Air adding another 5mm to the system depth to add a digitizer? And we’re not even discussing cost…


The MagicPoint digitizer is generally thinner. InPlay claims that the MagicPoint has the thinnest sensor grid. The grid has three loops – one for the X coordinates, one for the Y coordinates, and one for the power delivery – and puts the circuitry in a narrow strip beside the digitizer. The narrow strip appeared to be narrow enough to fit in an average bezel. While InPlay has not published the depth of any of the MagicPoint digitizers, when I got the chance to see one at CES, it appeared to be about 30-50% thinner than the Wacom solution, pushing it into the 1.5-3mm thick arena, which opens up new possibilities and new applications.


InPlay Technologies digitizer

                                      InPlay MagicPoint digitizer architecture

InPlay Technologies is marketing the MagicPoint digitizers in a variety of sizes and configurations, including pen-only input, pen and resistive touch MagicPoint MPRD, and pen and capacitive touch MagicPoint MPCD. Yes, the MagicPoint MPCD does support multi-touch!


It’s early days to say anything definitive, but on paper, the new InPlay Technologies MagicPoint digitizers look really promising. I hope to see one integrated into products in the near future. Wacom has had a tight hold on the digitizer market since the early days of Tablet PCs. With the new InPlay and the new N-trig digitizers, Wacom is getting a bit of healthy competition. Personally, I think that is a good thing. I hope that Wacom, N-Trig and InPlay are all able to secure healthy market share because ultimately that will help to drive the market forward much faster than the last few years.


If you want to read all about the InPlay Technologies technology, we have their whitepaper (from which I cribbed most of this data!) posted here.