Since the announcement of the iPad companies have been racing to get tablets to the market. A misconception about tablets is that a slate tablet will be good for writing on the screen. The technology used means that just isn’t possible. Read on to see why.


Microsoft first introduced the Tablet PC in the early 2000’s, but it is only in the past year has the concept of a slate computer caught the public’s fancy. Apple stoked the fire with the long rumored iPad, and last year tablet computers started to appear in all sizes. Many companies are currently working to produce slate devices, and one thing they all have in common is the touchscreen. Slate devices provide a natural use for operation by touch, so this is only logical. But there are a lot of misconceptions about touchscreens that are important to address, as not all slates will be as useful as many think they will.

The term touchscreen has become distorted to the point that it is often misused. Tablet PCs as introduced by Microsoft require a special digitizer and pen to operate; they do not work by touch normally. These Tablet PCs often are thought to have touchscreens, even though that is not the case. There are three types of “touchscreens” or digitizers in common use currently, and each has specific uses.

Active digitizer. This is the screen type used in the Microsoft Tablet PC. Active screens do not recognize touch at all, and only hovering or contact with the special pen that is supplied registers interaction with the screen. While these are not touchscreens, the proliferation of the other two types of digitizers have created a huge misconception about active digitizers. These are the only type of digitizer that have been successfully leveraged for handwriting on the computer screen.

Resistive digitizer. These screens have been around since the early PDA days, and were specifically developed to be used with a plastic stylus. A precise tap on the screen is required for accurate sensing by the digitizer, thus the stylus requirement. Touching such screens with a finger nail is also precise enough, enabling touch without a stylus.

Recently, light touch versions of the resistive digitizer have been incorporated in screens that have more sensitive response to touch. These do not interpret handwriting on the screen well like the active digitizer, due to the lower precision of the sensing and the inability to rest the hand on the screen. Resting the hand on the screen for writing on a device with a resistive digitizer results in an effect called “vectoring”, as any touch on these screens is interpreted as a deliberate action. This inability to rest the hand on the screen is the reason that most Microsoft Tablet PCs do not use resistive digitizers. UMPCs designed primarily for touch control aside, only one Fujitsu Tablete PC model line incorporated a resistive digitizer, the P16xx series. This required special “palm rejection” technology to ignore the hand resting on the screen while handwriting with a plastic stylus.

Capacitive digitizer. When we think of touchscreens currently, the capacitive screen is what commonly comes to mind. This is the type of touchscreen brought into the mainstream by the iPhone, and is by nature the only type in use capable of multitouch. The “pinch and zoom” feature of the iPhone is made possible due to the capacitive digitizer. This is the type of touchscreen in the iPad.

Capacitive digitizers work by sensing skin contact by the touching action. They do not work with pressure as the other two types; they require actual touch to register an action. This prevents the use of these touchscreens for handwriting on the screen, unless a special stylus is employed that fools the digitizer into thinking it has been touched by skin.

What does this mean in the real world?

Currently only Tablet PCs with active digitizers can effectively be used for “inking”, or handwriting on the computer screen. Attempts to produce tablets capable of properly allowing handwriting using resistive digitizers have not been successful, with the one exception by Fujitsu noted. Even that was not a complete success, as the inking on the screen was prone to skips due to the palm rejection technology.

Resistive digitizers have largely fallen by the wayside since the appearance of the capacitive type. The resistive type of touchscreen is still being used in many tablets being produced today, from those based on Android to many running Windows. These tablets cannot be used for handwriting on the screen in a productive environment. This is a big misconception that some have about tablets in general, that they can all be used for handwriting on the screen. There will be many people unhappy when they buy a slate using a resistive screen only to discover they cannot write on the display.

Capacitive digitizers can be used for handwriting if software is designed to handle the special stylus required. There are such apps on the iPhone, and when coupled with the stylus (also available through third parties) it is possible to write ink notes on the screen. This is not widely used nor has the capability been developed to the point of providing a full inking experience. Capacitive digitizers are more expensive than resistive types, and prior to the iPad no manufacturer has used one in a device larger than a phone. The true multitouch screen has been relegated to phone devices as a result, with the exception of expensive Tablet PCs that use two digitizers.

Dual digitizer systems incorporate both an active and a capacitive digitizer to provide the best of inking and touch. These require special technology that turns off the touch digitizer when the active pen gets close to the screen for inking, to prevent the erroneous sensing of the hand that results in vectoring. Touch the pen to the screen, and touch is totally turned off until the pen raises from the screen. This works well in Tablet PCs like the ThinkPad x200 I am evaluating, but it is not cheap to implement.

So what does this mean to you, the consumer interested in the tablets flooding the market? With just a few exceptions, virtually every tablet you see running Android or Windows is likely running a resistive digitizer capable of “light touch” sensing. These are good touch tablets, but do not expect these tablets to handle writing on the screen. The technology just can’t handle it.

The iPad is upping the touchscreen game by using a large capacitive digitizer. The multitouch experience is likely to be superb, but the OS used on the iPad is not designed to handle inking, even with a special stylus capable of it. There will need to be third party apps written to capitalize on this unintended capability, so it will not handle it out of the box.

Tablet PCs that run Windows 7 and have dual digitizers are the only devices currently available that can handle both touch (multitouch, too) and handwriting on the screen. These devices are much more expensive than the cheap tablets garnering a lot of attention recently, but you get what you pay for. The important thing to remember is if handwriting on the screen is vital to your needs, the cheap tablets are not going to handle it well, if at all.

To provide a full handwriting on the screen experience, the platform must natively handle it properly. Currently, only Windows 7 and Windows Vista have the capability. Microsoft doesn’t offer Windows XP Tablet Edition any longer, so any tablet with XP will not handle inking at all. Android is starting to appear on slates this year, but it has no native ability to handle handwriting on the screen. It will have to be developed by either Google or third parties to leverage that ability fully. The iPad doesn’t have the ability to handle handwriting either, but I wouldn’t be surprised to see companies produce solutions down the road.

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  1. What about the handwriting being discussed on the microsoft courier. I need to story handwritten notes mainly and secondarily use handwriting recognition. I grade papers by hand on tablet pc’s. Any thinking on whether ms courier thingy will be able to handle that?

    1. The concept videos out there would imply it can but it’s a fictional product until somebody officially announces it. Everything is pure speculation at this point.

    2. While it hasn’t been announced yet as mentioned below, the current speculation is that it’ll run on Windows CE. I’d have to imagine that they’d port over the Windows 7 handwriting recognition to it though. I mean, according to the interface demo videos, they plan on having it recognize handwriting, at least for web URLs and the like.

      Nobody knows if it’ll support say writing out notes and having the whole thing convert to text, like OneNote can do, or like you can do with the Tablet Input Panel though.

      1. The Slate definitely runs Windows 7 as shown at CES and these vids.

      2. Er, I mean, mentioned above.

      3. That’s nice, but Jim and I were speculating about the Courier. :p

      4. My bad! I totally mixed up the thread when checking comments on my phone.

  2. turn.self.off Monday, March 8, 2010

    did you miss the resistive multitouch screen found on the villiv S10?

    1. No, that’s the only device with that special digitizer and one of the reasons the S10 is much more expensive than other alternatives. I have one on the way to test out and will give further impressions when I’ve played with it.

      Initial reports have the inking experience to be abysmal, for the reasons I have mentioned here. Since multitouch is the only real advantage to the digitizer in the S10, I’d rather it have capacitive to tell the truth.

      1. “No, that’s the only device with that special digitizer.” What about Asus t91mt (~$500), t101mt (guessing ~$550) and most likely the Acer 1820pt (~$599)?

        I think with good palm rejection resistive would be far from “abysmal”. See: http://www.youtube.com/watch?v=_0p3DrL0xTs

      2. Information I have received indicates the two Asus multitouch systems you mentioned use capacitive screens. The same caveats for inking apply as stated in the article.

      3. Thanks for clarifying James. Someone should tell all the t91mt owners and t101mt early reviewers that they have been misinformed.

  3. Ubuntu works amazingly well with Tablets.
    A refurb x40 tablet running Linux/Ubuntu is a stellar and very inexpensive Tablet option.

  4. I’m using the Lenovo S10-3t which features a capacitive touch screen (10 inch). This device runs Win 7 and costs $499. So the iPad wouldn’t be the first device with a large capacitive screen. When using a Pogo stylus, the inking experience is pretty good.

    1. You are right on when pointing out the Lenovo has a capacitive screen. Lenovo uses it on the dual digitizer ThinkPad I mentioned too.

    2. Kathryn Bigelow Monday, March 8, 2010

      You don’t need no stylus with an iPad. You’re thinking has been warped by your reality distortion field you can’t seem to escape. The iPad will show you a better way. Try hard not to think like a backward WinMo type user and enter the bright forward thinking world of the iPhone OS, you can thank me later.


      1. True.. And I don’t need a stylus on the Lenovo either… I just prefer writing with a pen over writing with my finger…

        Don’t you have a few Oscars to be buffing about right now?

      2. I honestly hope that’s Internet sarcasm…or a trolling attempt. I really do.

        Do you know why people use the phrase “pen and paper” instead of “finger and paper”? That’s right-people do not write and draw with their fingertips the vast majority of the time. Fat fingertips do not offer the precision or fine inking of a good fine-point pen.

        It’s not the pen I want to get away from-it’s the paper. Very kludgy stuff to work with-it can be lost, it’s not easy to search or duplicate perfectly, editing is more difficult, and so on. Pen tablet computing is about freeing us from the restraints of paper, is it not?

  5. Great Article. Thank you James.

  6. Dell XT2 has a 12.1 inch multi-touch capacitive digitizer.

  7. Just out of curiosity, how much more expensive are the dual-digitizers. And how many companies make them. I know that InPlay used to do so with the Panasonic H1 but they are now out of business.

  8. I have been using HP’s tablets since the TX1000, when that broke, bestbuy gave me a TX2000(got to love a warranty), now I have the TX2500, the latest one before the TM2…I made sure I moved fast and got the TX2500 over the new TM2 because I wanted the Faster AMD processor, plus I already have 3 batteries for it since my original TX1000. I will not cry when the time comes to get the tm2, but we will cross that bridge once i have to go there.

    The original tx1000 used a single resistive digitizer, while the tx2000 used a dual digitizer that had both resistive and active digitizers with the use a wacom stylus. The TX2500 used a Capacitive digitizer, and a active digitizer for the best experience I have had so far. The TM2 uses this same combination. Although the downside to this is I can no longer use a un-clicked pen to click on the screen if i want to (small lose)

    My Experience with MS OneNote 2010 and Evernote has been great for taking notes in school in conjunction with Evernote on my iphone. Every handout i get gets scanned with my iphone 3gs camera, sent to my pc via Evernote via synce, then dragged into OneNote. Once that’s done I can pinch to zoom with my fingers and ink on any park of the handout (that is actually a image file, so its like drawling on it in MS paint)

    When note taking from a power point, I can do the same thing…and ink illustrations in between…or rotate for the keyboard if i need to add more then a line or two of text.

    Tablet PC’s are extremely usefull for me! I am looking forward to them all. I plan to purchase the Ipad for when i need to be a bit more mobile then my HP tablet will allow (more for social interactions with digital media, the for productivity)

    I look forward to the innovations from Microsift and other tablet pc companies to keep innovation alive, so I can move on from my HP tablet wen the time is right.

    1. How do you drag evernote pictures into onenote?

  9. Hi James,
    Thanks for publishing this informative article. As you know, TabletKiosk has been manufacturing and distributing dual mode Slate PCs with Active Digitizer and Resistive Touch for years. As a result of all of the recent iPad hype, we are seeing a surge of interest from companies that are looking for a slate form factor combined with a full Windows OS.

    One other thing that I want to point out is that although XP is no longer offered, when TabletKiosk customers purchase a new Digitizer tablet with Windows 7, they still have the rights to downgrade to XP Tablet and we provide the XP Tablet restore disks for free.

  10. Kathryn Bigelow Monday, March 8, 2010

    Does everyone here suffer from Stylus Separation Anxiety or what ?

    1. The precision that a stylus offers can not be substituted by the finger. Writing utensils have been around for thousands of years,and they have all maintained the same basic design…the design is that of a stylus or pen.

      The finger is great for grose, quick movements, but for productivity, a digitized pen is far for functional.


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