feature article
Subscribe Now

A New Angle on Old-School Writing

Atmel is Lining Up to Own Styli

Left-handers have been handed a disadvantage when it comes to Western scripts.

For right-handed people, you get to see not only what you’re writing, but also what you’ve already written, since your writing hand hovers over the blank portion of paper that you haven’t written on yet.

Not so for the left-handed. Their writing hand covers the portion they’ve just written, making visible only the mark being written at that very second. I’m assuming that’s why left-handed writers often position their hand in a way such that the pen comes down from the top instead of leaning to the left – at least you get a couple letters’ visibility.

Being right-handed, I haven’t been so inconvenienced. At least, until I started monkeying with other scripts. With Chinese and Japanese, for instance, you can choose left-to-right, like Western scripts, or up-to-down with columns starting from the right and moving left. But, in the latter case, you can pretty much see the characters you just wrote as you write beneath them; the only issue is smearing ink with the heel of your palm.

It gets more serious with true right-to-left scripts, as I found when trying to learn a bit of Arabic. Now I got to see how the other side lives over here: you never really appreciate writing visibility until you lose it.

In all of these cases, no matter how limited your view, you can at least see that portion that you’re writing, even if only that. So imagine what a hassle it would be not to be able to see even that, or at least not well. Such is the case with passive capacitive styli.

That’s one of the primary issues that Atmel is attacking with their recent ActiveStylus technology. With its 1-mm tip, it’s much more like a pen that you can see around – unlike a passive stylus, which has a tip on the order to 2 to 3 mm.

But why does a stylus even matter? And how have they done this?

Styli are poised to become a standard part of the user interface for various devices. Again. For those of you that used the early Palm Pilot devices, you will recall that any self-respecting PDA had a stylus. But they’ve largely gone out of favor – for some reason, people seem to think that fat fingers and thumbs somehow work better than a thin, precise utensil. Well, at least a finger is harder to lose…

And, of course, this all becomes more relevant with the proliferation of touchscreens. First in phones (the modern-day PDA) and then in tablets. There’s only so much you can do with a phone (despite the miracles everyone promises); tablets open up more possibilities, especially for artists, and, apparently, even Windows 8 will recognize a stylus as a standard part of the repertoire, as will Android 4.0.

If handwriting recognition works well (sorry to remind you about Palm handwriting recognition – cool in its time, but would suck to do lots of writing), then we really could start writing the old-fashioned way again instead of typing. And if it can read my handwriting, I’ll be really impressed – I’m lucky to be able to read it myself a day after writing…

But this isn’t about handwriting; it’s simply about the stylus. Let’s start with how they work and interact with a touchscreen.

The touchscreen is built with a number of layers. A non-touchscreen would have just a display layer and a glass cover layer. The addition of a thin film of indium tin oxide (ITO) allows for touch sensing. The nice thing about ITO is that it is conductive, and so it is useful for sensing while at the same time being transparent in thin doses, so it can go over the display without interfering with the display. This layer is what makes a screen a touchscreen (well, that and the touchscreen controller that interprets the touch events).

There are, by Atmel’s reckoning, three basic main stylus technologies today: inductive, passive capacitive, and active capacitive. The “best” performing type of stylus is inductive, but such styli need their own sensing layer, which goes under the display layer. This adds cost, making them less attractive for high-volume mass-market applications.

By contrast, capacitive styli can use the same ITO sensor layer that serves to detect your finger. This makes the screen cheaper. So what’s the active/passive deal?

A passive stylus simply has a material that will perturb the electric field around the sensor, much as your finger does. All information about contact with the stylus comes from the touch sensor itself. Because the effect being detected is relatively subtle, the stylus tip has to be large enough to be noticed. Hence their relatively bulky nature (while admittedly slim by comparison to a finger).

The ActiveStylus technology that Atmel is touting puts electronics in the stylus. This lets the stylus announce its presence, so it doesn’t need to be as big – that’s why the smaller tip. In fact, the stylus tip communicates with the touchscreen across the small gap between stylus tip and touchscreen sensor.

Stylus circuitry and a way of talking to the touchscreen provide an opportunity for more smarts and features. You can now have a stylus with a pressure sensor: while the touchscreen figures out where the stylus is on the screen, the stylus itself is reporting how hard you’re pressing. It can also have a tilt sensor and report the amount of tilt. And some companies like to provision their stylus with a button, so a button-press event can also be communicated.

All of which sounds good. But if you think in terms of doing actual handwriting on a tablet, stop for a minute and think about what is probably the most common stylus/pad out there: those point-of-sale pads where you sign for your credit card transaction.

Now admit it: has there ever once been a time when whatever it is you managed to scrawl on that thing looked even remotely like your signature? Hell, you could probably challenge every purchase you made in the last couple of years, and no one would be able to say that you really signed it.

There are lots of reasons why they come out looking horrible (not least of them because the dang thing hasn’t been maintained and isn’t working anymore and ok, whatever, just make a display of pseudo-signing so I can get to the next guy in line…). But I find that the biggest issue is that I can’t rest my wrist. So I’m writing with my whole hand floating in the air, using my gross arm motor skills instead of my fine wrist and finger motor skills. The result isn’t pretty.

So if we’re really going to be able to write, we’ve got to be able to put our wrists or palms down. And you know what happens when you do that on a laptop touchpad; nothing. Call it overstimulation or whatever; when the palm goes down, the pad freezes up.

It’s for this reason that Atmel is drawing particular attention to their “palm rejection” technology. This allows you to write with your hand in a natural, comfortable position without freaking out the machine. It’s not clear exactly what the details of this technology are, but, clearly, having a stylus that says, “Here I am” must make it a lot easier.

Atmel is jumping in aggressively here. They claim – reasonably – that equipment makers want a single stylus architecture for use both in handsets and tablets, and they seem to be trying to take that beachhead. You can’t mix and match screens and styli – the ActiveStylus technology works only with Atmel’s touchscreen controller, and the communication protocol between stylus and screen is proprietary. So when you marry the stylus, you marry the family.

Whether they’ll be challenged for pole position is unclear. But if this kind of technology lives up to its promise, at some point you’ll be able to write naturally into your computer, and you’ll be able to see what you write as you write it. Whether you’ll be able to see what you already wrote depends on your handedness and your language. At the very least, you won’t be smearing any ink. 

Leave a Reply

featured blogs
Dec 4, 2023
The OrCAD X and Allegro X 23.1 release comes with a brand-new content delivery application called Cadence Doc Assistant, shortened to Doc Assistant, the next-gen app for content searching, navigation, and presentation. Doc Assistant, with its simplified content classification...
Nov 27, 2023
See how we're harnessing generative AI throughout our suite of EDA tools with Synopsys.AI Copilot, the world's first GenAI capability for chip design.The post Meet Synopsys.ai Copilot, Industry's First GenAI Capability for Chip Design appeared first on Chip Design....
Nov 6, 2023
Suffice it to say that everyone and everything in these images was shot in-camera underwater, and that the results truly are haunting....

featured video

Dramatically Improve PPA and Productivity with Generative AI

Sponsored by Cadence Design Systems

Discover how you can quickly optimize flows for many blocks concurrently and use that knowledge for your next design. The Cadence Cerebrus Intelligent Chip Explorer is a revolutionary, AI-driven, automated approach to chip design flow optimization. Block engineers specify the design goals, and generative AI features within Cadence Cerebrus Explorer will intelligently optimize the design to meet the power, performance, and area (PPA) goals in a completely automated way.

Click here for more information

featured paper

Power and Performance Analysis of FIR Filters and FFTs on Intel Agilex® 7 FPGAs

Sponsored by Intel

Learn about the Future of Intel Programmable Solutions Group at intel.com/leap. The power and performance efficiency of digital signal processing (DSP) workloads play a significant role in the evolution of modern-day technology. Compare benchmarks of finite impulse response (FIR) filters and fast Fourier transform (FFT) designs on Intel Agilex® 7 FPGAs to publicly available results from AMD’s Versal* FPGAs and artificial intelligence engines.

Read more

featured chalk talk

Portable Medical Devices and Connected Health
Decentralized healthcare is moving from hospitals and doctors’ offices to the patients’ home and office and in the form of personal, wearable, and connected devices. In this episode of Chalk Talk, Amelia Dalton and Roger Bohannan from Littelfuse examine the components, functions and standards for a variety of portable connected medical devices. They investigate how Littelfuse can help you navigate the development of your next portable connected medical design.
Jun 26, 2023
19,537 views