Wednesday, February 18, 2009

Turn a Standard Laptop into a Tablet - Pen DUO

A little bit of writing that was done on my $350 Acer Laptop.
A Tablet PC is a PC that you can take notes on, annotate pdf's, emails etc.  Also known as the best thing ever for a college student.  However, they tend to cost around $800 even for the cheapest ones, and that is just too far out of the price range for a poor college student like me.  So instead I found a way to turn my $350 Acer laptop into one!  It doesn't look completely ridiculous either...Minimizing ridicule is always a good thing :)
The product I found is called the DUO. The company refers to it as a 'Pen Mouse' because it serves both mouse and pen functionalities. It looked legitimate enough after I found a couple videos on youtube such as this one, below:
Notice that the size of the device at the top of the monitor is small and sexy.
No ridiculing to be had here! :)
So, how does it work?  The pen sends out an ultrasonic sound (you can barely hear it if there's no background noise) and a reciever measures the time for the sound to travel to it - so by physics 101, you can derive the distance...because distance = velocity * time.  When you want to draw, lightly press the pen against the screen - this'll push the tip of the pen inward slightly and essentially click a switch in the pen, changing the signal, which tells the reciever to 'draw'.  Neat!
Purchase it - $80-100
So if you're getting excited like I was, you're probably saying, "Sign me up!" but where can you purchase it, and how much does it cost?  A google search for 'Pen DUO' basically results in the company webpage ( and that's about it.  The only place to actually purchase it is on Ebay, and all vendors are based out of Korea, because that's where the product is made.  So..this started to sound pretty sketchy, and in all honesty if I had not seen the video above I probably wouldn't have actually purchased it, but the vendor offered a full refund if the product didn't work as advertised, and paypal had buyer protection, so I felt pretty safe.  
The overall cost for me was $98, and considering I spent $350 on my laptop I was still getting the tablet functionality for a good $300 less than the cheapest tablets on the market.  I found the same vendor selling it a week later for $78, so look around first!
A Review of the DUO
I recieved the item in a record 3 days from Korea, and with free shipping!  Most excellent.  It came in a pretty box that looked like an Apple product.
Its as professional as I could get with a cellphone camera!  Pretty box though :)
Inside was the unit and the pen, both of which were much smaller than I expected.
It also came with a nice little carrying bag, replacement pen tips, a slew of manuals, a nice CD, and some batteries.
Please note, the CD does exist, I just couldn't find it for this picture...but it comes with one :)
Here's my awesome $350 Acer laptop, just to give an idea of what it will be attaching to.
She's oldish but gets me through all the development work I need to do :)
The reciever attaches to the laptop via a pretty strong magnet.  Make sure you keep the reciever away from magnetically sensitive things (i.e. credit cards)!  The magnet is attached to the laptop with a very sticky adhesive.  You can place the reciever on the top, left side, or right side of the laptop.  I chose the top.
You'll want to be careful to place the magnet exactly where you want it - 
because I'm not exactly sure you can reposition it very many times.
Here's what it looks like when it is attached.
Pretty low profile :)
Here's another angle.
When you first plug it in, and insert the CD, all you need to do is install the calibration software.  I'm running the Windows 7 beta and it automatically detected that I had an input device that lets me write on the screen.  After a quick calibration like so...
Just gotta make sure it knows where the edges of your monitor are...
I was able to write just as if I had a real Tablet PC!
There really isn't any lag, and it feels like you're writing!
But wait, there's more!
So the other really cool thing about this device is that you can remove it from the top of your laptop, place it on your desk, clip a piece of paper into it and write on the paper and have it transcribe it directly onto your monitor as well!  There are replacement ball-point pen tips that enable you to take notes on notebook paper and retain a digital copy for those of you that might find writing on the screen vertically a bit awkward.
  1. Is it good to write on my LCD screen that wasn't designed to be a tablet?      - I don't think it is really good to do it directly with the has a felt tip, which is pretty gentle on the screen, but I think you should definitely invest in a screen protector if you're going to get one of these.  They go for about $10 on Ebay.
  2. The pen freaks out in some rooms, and not in others?     - This has to do with the fact that some light conditions, such as those offered by flourescent lights, for example, can output a very deep humming sound that can interfere with the sound emitted from the pen.  This causes the pen to act 'broken' even though it isn't.  I've found that this is rarely ever an issue although I do have one classroom where this is the case - luckily I don't really ever take notes in that class, so just something to keep in mind.
  3. Writing on the screen vertically looks really awkward.     - Honestly, this was the thing I was most concerned about.  Standard Tablet PC's allow the monitor to rotate around and lie flat over your keyboard so it's like you're writing on a piece of paper.  I do wish that my laptop was capable of such a feat, but in all truthfulness you do get pretty used to it after a while.  Yes... you probably won't have perfect accuracy or your finest handwriting, but you can definitely take notes, and it's not horribly awkward.  Truthfully it'd be the one thing that I would change...but it really has nothing to to with the product.  You could always just put the reciever on a flat surface and just write on that, as it doesn't know what is your monitor and what isn't :)
This is probably the cheapest solution to obtaining tablet functionality without spending huge amounts of money on a tablet.  It works really well and install was a breeze, plus it looks really slim and sexy.  It has a few drawbacks, although they're certainly able to be worked around or just overlooked if you're desiring tablet functionality.  For me, it's been a great investment and a great study tool.  I didn't see any reviews for this product out there on the internet, so hopefully it helps you decide whether or not it's worth the money.
If you have any questions, comments or advice, please leave a comment below!


  1. You can buy in

  2. I am interested in trying this for my artwork. How is the sensitivity with the pen? Is it comparable to the other laptop tablets such as the Toshiba and the HP?

  3. I asked my brother to compare a while ago since he has a Toshiba tablet and he said it was comparable. Although... I'm not sure how precise you'd be able to draw, just due to the fact that the sensor isn't located in the pen tip but right above it. So if you tilt the pen it still treats the pen tip as being right below the sensor even though its now to the side of it (resulting in the drawing not matching your pen location).

    I think for drawing you may want to go with a wacom tablet, those are pretty cheap nowadays and are much more suited for artwork in general!

  4. Do you have any idea if these work in OS X?

  5. Its very possible since the computer literally just treats it as a pointing device...Although without the screen calibration software it could be frustrating..

  6. It works really well and fast. Install was a breeze. Its also very slim and looks stunning.

  7. You can find this product for $99 on . The company ships worldwide and the shipping costs are low.

  8. Manufacturers have created a goal of software and hardware by producing tablet computers.

  9. manufacturers have done a great job by producing a tablet computer of software and hardwares.

  10. Where can i buy this? How long is the delviery period? What is the procedure to buy this? How to collect the product? they delieved to our hse or?

  11. Although without the screen calibration software it could be frustrating..

  12. I found this ( ) and it looked the same... I was wondering if it is the same!? Should i take a chance and buy it?

  13. I would like to appreciate the work of blog author that the person provided us with an extremely excellent information about this laptop

  14. the cheapest ive seen to buy it is on ebay at $89

  15. This is so nice. This will be so easy now for art work. I really appreciate your idea. Thanks for sharing. tablet pc