EMR and tablet PCs - learn more
Digital ink recognition & conversion
By now almost everyone understands what a Tablet computer is, a portable “laptop” that can be used with a stylus, a touchscreen or both. They are connectable to the Internet or other wireless networks. But, with the march of computer technology more choice is now available. Not all the choices are the best for every particular use. For business it is important to match the use with the right computer. Medscribbler is medical business software users will interact with six to ten hours a day, so the right choice is important. It runs best on a Microsoft powered Tablet PC.
What are the capabilities of a Tablet PC that need to be understood to make the right choice, especially for use with Medscribbler? Not all Tablets are created equal, first let us deal with the Apple iPad myth. There is confusion in thinking an iPad can simply be used instead of a Windows Tablet PC.
Apple’s iPad is not a “Macbook Light” computer, it is more an “iPhone heavy” communications and media device. As a result, it has significant weaknesses compared to Tablet PCs using Microsoft operating systems, especially Windows 7. Windows based Tablet PCs use a full operating system with added features which makes them a “Laptops Plus”. The iPad operating system uses a moderately enhanced iPhone operating system. This iPhone system is comparable to Windows CE that Microsoft produces for Smartphones. In addition, the iPad is lacking many hardware and software features that come standard on a Windows Tablet PC.
The iPad has no support for Adobe Flash, no multitasking, no USB ports, no available attached keyboard, limited CPU and memory power, etc. It is a consumer device built, first and foremost, for media consumption; for music, movies, and Web surfing. Applications for the iPad are available that can perform single focus tasks, usually with an Internet connection. These applications are mostly the same as those for use on cell phones. The biggest disadvantage of any Apple computer is the lack of any credible recognition engine and why Apple has focused on “touch” screen computing. The iPad does not have usable handwriting or voice recognition systems, nor are any available for it. Apple’s screen technology is limited.
There are four types of screens for computers. A regular display only screen, a touch screen, a multi-touch screen and a digitizer. A regular display only “displays” the cursor or a point that is processed through the computer from a device attached to it; the keyboard, a mouse, or even a drawing pad. Digitizers have an extra layer that is sensitive to specially designed pens. The touch screens also have an extra layer over the display screen that is sensitive to physical touch only (also called passive or resistive touch.)
This touch sensitivity easily allows many navigation functions to be performed right on the screen, for example swiping with a finger to move to the next screen. The software of the touch screen plots the X and Y co-ordinates of the physical touch of the screen. A multi-touch screen is capable of plotting multiple X and Y co-ordinates at the same time. A digitizer screen is a capacitive touch screen that can plot many more co-ordinates including depth or pressure even without direct contact with the surface.
The X and Y touch screen only plotting has allowed software to be developed for drawing art and to easily recognize letter shapes, character recognition. Accurate cursive handwriting or even sentence recognition requires intelligent software to “recognize” the plotted points and translate them into words, rather than the simple letters. The Apple OS X has a very basic handwriting character feature included. If a graphics pad is plugged into a USB port a character recognition feature is activated. The iPad does not have an USB port nor the character recognition software. For Linux, limited open source handwriting user trained recognition software is available. Microsoft is the only company to provide software that can recognize cursive handwriting. It is based on a time delay neural network (TDNN) classifier, nicknamed "Inferno." For business use a Microsoft based Tablet is the only viable option.
The Microsoft recognition engine functions best with a digitizer screen only on a Tablet PC. Many Tablet PC manufacturers reduce the retail cost of their Tablet PCs by using much cheaper passive or “touch only” screens. To avoid “false touches” and allow the handwriting recognition to work the touch sensitivity is reduced or a layer of plastic is placed over the screen to increase the touch pressure required. Accuracy of the recognition is affected negatively. For users without a need of handwriting conversion or extensive handwriting these cheaper models are sufficient.
Other Tablet PC model vendors take the opposite approach and include both a passive touch screen and an active capacitive digitizer screen layered together. The extra screen component adds to the weight and shortens the battery life of the Tablet PC. There are often point location anomalies, similar to the dislocation of looking through the surface of pond water. Often those using the handwriting recognition or an application that involves the use of a pen eventually turn the touch off as the active pen is in their hands anyway and it can do everything a finger can, and more accurately.
Digitizer screen only Tablet PCs have more accuracy than “touch” only screens as they plot many more X and Y co-ordinates. Compared to combined “touch and digitizer” screen Tablets they are lighter, have longer battery life and do not give false touches. Because of the added pen accuracy digitizer only screens are the choice for applications for art work, annotating documents or handwriting to text conversion. In most cases, digitizer screens are the type recommended for Medscribbler with its use of document annotation and handwriting recognition.
Tablet PCs using the Microsoft operating system take full advantage of the recognition system. This system is just not for handwriting but is also the for voice recognition. Tablet PCs have voice recognition that translates to text. As well, navigation commands are recognized. There are third party voice recognition systems like Dragon Naturally Speaking that can be used instead of the Microsoft’s included voice system, but most find the Microsoft Windows 7 version to be superior. Apple’s OS X has a limited command recognition engine. There is a version of Dragon Naturally Speaking called Macspeak available for Apple, but it is not available for and does not work on the iPad.
Recognition systems use a general dictionary of words that can be added to. With Windows 7 the recognition engine can be “trained” to more readily recognize an user’s handwriting and voice. Many users find in Windows 7 it works very well without training. Windows 7 also has a predictive system that “learns” as it recognizes. Applications, such as Medscribbler, that are based on the Microsoft Tablet PC capabilities can also employ many programming tools that Microsoft makes available for recognition. These tools can greatly increase accuracy by making the recognizer context aware. Other recognizers, like Dragon Naturally speaking, are very limited in this ability.
The ability to navigate, draw or write on the screen is the main difference between a regular laptop and a Tablet PC. This is for mobility as using a keyboard is not always practical, as in medicine. Because of this ability some Tablet PCs come without a keyboard and are called “slates.” They are designed to be very mobile. Simple media use “slates,” like the iPad, usually have small 10inch and smaller screens. Business use Tablets with a keyboard or as slates are usually a 12 or 13 inch screen to emulate paper’s size. Art work business computers are usually larger digitizer screens. Business use Tablet PCs often are purchased with extra bright screens for work under florescence lights.
