In the past, the interaction between humans and computer systems was limited to the use of a single finger and one mouse pointer. These traditional interfaces denied users their dexterity (Nadine 2). The development of multi-touch technology is aimed at giving users more versatility when interacting with their computers. This allows humans to accomplish more tasks on a computer within a shorter period. By making use of more than three or more fingers one can zoom, drag, rotate, flip when arranging videos or photos.
Multi-touch sensors give users the ability to input data into a system using three or more unique points of touch on the interface (Han 1). This technology is rapidly changing how users can interact with their computers. Multi-touch interfaces can understand when several humans use their fingers to input data into a single computer system. Users can vary the commands they input by changing the gestures they make with their fingers. The gestures that the users use to perform different tasks on a multi-touch device are similar to the physical gestures that get the action done in the real world. Thus multi-touch technology seems to create a thin line between line between the real and virtual worlds. Advanced multi-touch interfaces can recognize changes in pressure and even temperature when a user uses his/her fingers to press on specific points on the multi-touch surface.
There are currently five major techniques that are being used to produce stable multi-touch capable interfaces (NUI Group 13). One methodology of multi-touch is the Frustrated Total Internal Reflection (FTIR) that was developed by Jeff Han. This system makes use of infrared light to differentiate between the visual image on the multi-touch surface and the finger(s) being tracked by the system. There is also the Diffused Illumination (DI) methodology that can be further subdivided into Front Diffused Illumination and Rear Diffused Illumination. Microsoft’s Surface Table makes use Rear Diffused Illumination technique. Diffused Illumination relies on the contrast that exists between the finger that touches the image on a multi-touch surface and the silent image on the surface. Other techniques of creating multi-touch surfaces include LED Light Plane (LED-LP) technology, Diffused surface illumination (DSI), and Laser Light Plane (LLP). Each of the above methodologies has its pros and cons.
Multi-touch systems offer various techniques during the process of acquiring data from the users and converting it into correct software parameters needed in executing a particular task. One mode of interaction is gesture-based interaction, which allows users to use speech, gestures, and bodily expressions to input data into the system. Secondly, there is the pressure sensitivity-based mode of interaction where users use their fingers to input data. Lastly, there is the multi cursor and precise selection technique that allows users to interact with the multi-touch system like how they would interact with the object in a real-life situation.
Significance of multi-touch technology
The greatest significance of multi-touch technology is in its ability to replace traditional mice, stylus, and keyboards as the primary device for inputting and manipulating data in a computer system. Computer applications are becoming more sophisticated each day thus resulting in the need to refine means by which we interact and manipulate data within these systems to enable us to get the maximum out of them. Multi-touch systems allow us to discover new possibilities that were unachievable using the traditional mouse and keyboard interface.
This is especially advantageous since the technology allows multiple users their to use their fingers simultaneously to input data into a multi-touch system that allows for collaborative effort of all the users available at the interactive tabletop (Elezovic 3). Hence multi-touch allows work to be done in a faster and more effective manner since many users can interact with an application at the same time. This has been achieved by the ability of multi-touch interfaces to allow for multiple simultaneous points of contact between multiple users and a computer interface. This can be of great advantage especially in situations where many users can input commands on a large screen.
Multi-touch technology allows users to more directly interact with the data and computer applications they are using by trying to create a bridge between the virtual and physical worlds. For example when handling photos or documents, the users can rotate, turn them over as if they were dealing with a physical photo. By swiping a finger across the multi touch interface the user can turn the page on a document. These devices respond to the hand and finger gestures in a manner that most users can describe as natural thus making it easier for a user to try more complex gestures to see how the system responds. Through this the advanced multi touch technologies slowly eases its way into the life of non technical people enabling them to use easily complex computer applications in their daily lives.
Multi-touch greatly enhances usability of a system by allowing users to use both hands along with cording gestures as compared to traditional systems that limited users to only interact with the system using one finger at a time. Furthermore, the gestures done by the fingers of the user reflects the natural gestures that a user can use to achieve the desired result in a real life situation. By making effective use of multi-touch technology, we can significantly increase what is achievable by a computer system thus making the achievable possibilities are virtually endless.
How the multi-touch system differs from point and click interface of Windows
Using multi-touch technology, humans can now increase their levels of interaction with computers beyond the traditional simple pointing and clicking, pushing of single buttons at a time, dragging and dropping. Limited user interaction when using the traditional point and click can be illustrated by the inability of the user to perform many tasks simultaneously, for example trying to scale and rotate an image at the same time. These limitations have been eliminated by using multi-touch interfaces. The multi-touch interface allows for the user to interact with the system using multiple cursors thus doing away with the limitation that was caused by using single point and click devices in the past.
Unlike a traditional keyboard, mouse or touchpad that allows single-point input, multi-touch technology give users richer interaction between the user and the system by introducing diverse command input actions such as rotations, swipes, and pinches. The multi-user interface provides a virtual keyboard that is re sizable to fit the needs of the user, this shows the level of dynamism that can be achieved. The multi-touch surface can be taken to be a screen that allows input of commands through many cursors, each cursor being represented by the users or fingers inputting the data at the same time. This ability to accommodate many points of input simultaneously sets it apart from the traditional single point and click mouse interface.
Multi-touch technologies give users the ability to perform several tasks at a time thus increasing user experience. This cannot be achieved when making use of the traditional point and click interface. For example it is impossible for a user to manipulate two images simultaneously in the windows point and click interface. By being able to perform several tasks at a time the user involvement with the system is increased tremendously. The user feels as a part of the system they are working with, thus encouraging more productivity in the workplace.
It is impossible to achieve all the benefits of multi-touch systems using the traditional mouse interface of Windows and Mac. The traditional Windows and Mac interface has only one cursor or pointer for the mouse thus it cannot allows input from different users. Even with the use of multi-touch mice users cannot achieve the levels of flexibility in interaction with a computer system, that are offered by multi-touch surfaces. It is impossible to duplicate the multi-touch gestures that can be executed by a multi-touch system using the traditional mouse. As seen earlier these near physical gestures drastically increase the interactivity between user(s) and the computer system.
The multi-surface technology can be used to improve user experience in day to day applications and activities. It is expected that the expanded use of the technology will continue to grow at a fast pace. One such user activity that can greatly benefit from the use of this technology is the hotel and drinks industry (Friedman22). In future the technology can be used to create virtual concierges where customers can order their foods and drinks via a multi-touch surface. The entered data is sent to the kitchen for further processing. The customer can afterwards make payment by placing a credit card on the multi-touch surface and the system processes the transactions safely. The multi-touch surface technology would then allow simultaneous orders and payments to be made by several customers using one surface at the same time. In addition, the system will offer customized entertainment to the customer by enabling them to browse through popular social web sites, watch videos ad even read news while enjoying his food at the virtual concierge. This would greatly increase the customer experience at the hotel and also reduce the cost of hiring many workers to serve the clients.
Another system that could greatly improve under the incorporation of multi-touch technology is the customer shopping experience at the. Through the integration of multi-touch technology, cell phone companies can allow their customers to purchase air time and browse through the available product features and price plans. This system will be configured to detect automatically the type of phone placed on the surface then present the available options for the customer to compare their features. Payment for the selected services can then be made by placing a credit card on the surface.
In the home and working environments the multi touch surface technology can in the future be used to ease the organization, transfer and storage of data between different types of devices. According to Vitaly, Users can transfer data by placing Wi-Fi enabled devices on the multi-surface table and then touching the system to download or send the data (20). The surface can recognize the different devices placed on it. Users can then send data to any device placed on the surface by simply sliding the photos, files or videos towards the target device. The device would then automatically copy and save the data. By doing this the users can create a virtual server through which they can find information without having the hustle of cables or more complex data sharing systems.
The future of the multi-touch system
It is generally expected that the multi-touch technology will continue to grow by making it easier and natural for humans to interact with these systems while at the same time ensuring that it offers more advanced services. This will include increasing the ability of the multi-touch system to understand a wider variety of gestures. The future is bright for multi-touch interface developers; more and more people are steadily embracing the new technology and using it to maximize their interaction with computer systems (Dolby 4). Soon advanced multi-touch will give humans the ability to interact with computers more naturally in a manner similar to how they manipulate physical objects.
Elezovic, Samir. Multi Touch User Interfaces. Jacobs University Bremen: Bremen. 2008. Web.
Friedman, Vitaly. Multi-Touch Surface Technology. Saarland University: Saarbruecken. 2007. Web.
Han, Jeff. The future of Interfaces is Multi-Touch. NYU’s Department of Computer Science: Washington. 2007. Web.
Nadine, Dolby. “7 Things You Should Know About Multi-Touch User Interfaces”. Educause Learning Initiative series. Educause: New York. 2008. Web.
NUI Group. Multi-Touch Technologies. Nuigroup.com: California. 2009. Web.