1. What is it about

You have arranged a meeting and your visitors have just arrived. You guide them into the appropriate meeting room and after the initial greetings everyone is getting themselves prepared for the meeting to start. Naturally, you want to exchange business cards with everyone and also distribute some flyers about the projects you are doing. Everyone place their mobile phones on the Display Table at the centre of the meeting room. You simply drag all the files by your finger to the mobile phones that are placed on top of the screen. The files are copied wirelessly to their mobiles. The process is secure since only those mobiles that are physically on the screen will get the files and you know that the system will take care of the rest. Sometime later, everyone is standing next to the screen hanging on the wall. Everyone is busy rotating the 3D models so they can get a feel for this new version of the plastic toy you want to manufacture for your customer. Working simultaneously, they use their fingers and use touch gestures to interact with the screen, zooming, rotating and shaping the model as they like.

Display tables are displays that are laid out horizontally with touch sensors. The sense of touch is captured with different techniques such as camera, pressure or temperature sensors.

Since you can use touch, it is believed that you will achieve certain tasks more naturally and intuitively. For example, to do a drag and drop, you may use your finger to touch the display and move one digital object from one place to another place. You can also use the device collaboratively with someone else to exchange digital material. The beauty of this interface is that you won’t need any instructions to operate a new software service. You can use your intuition to find your way around and interact with objects displayed.

2. Where is the fun

• Manipulating a 3D world with objects and touch can be a whole new experience. Tactile sensing is very natural to humans and the current implementations of user interfaces have not fully explored this area with single point devices such as mouse.
• Sitting at a table in a high-end restaurant and playing with the display while waiting for your food to arrive is a nice time killer, provided you are not completely absorbed in your date’s eyes!
• Working with a computer while standing next to it can be a nice exercise for those leg muscles.
• We can do away with keyboard and mouse and finally use a computer in a whole new way. Of course, multi-touch is not a replacement for other type of interfaces, just another potentially useful form of human-machine interaction.

3. What are its Applications

Multi-touch displays can be used in three main types of configurations: as horizontal, as vertical and in small device.

The horizontal version, a multi-touch display table is an attractive collaborative tool. Users can sit around a table and chat about the data displayed while also interacting with it. You can also place objects on the display table and get them to interact with it. A vertical or semi vertical display can be used in many different applications in particular for manipulating rich media such as images, 3D models, maps, geological information systems, games and even general file management.

Small devices are another type of products that can benefit from multi-touch since you want to easily interact with them through a usually small screen.

Using a multi-touch display you can:

• View spreadsheets, graphs and intensive data projection tools that require a large screen and need to be fine-tuned and manipulated as the meeting progresses.
• Use mind mapping tools for brainstorming. Everyone can work on different parts of the display and later combine the modifications together. Once everyone is familiar with the process, this type of collaboration may lead to better efficiency and team output. It will also help team binding.
• View 2D and 3D maps with a variety of information layers shown on top for planning and scheduling. The large size of the display and the ability to use gestures to navigate around the map will make it a natural tool to use. In addition, it will be possible to put physical objects on the display and use them to interact with the digital content.
• Play games using hand gestures, multi-touch and physical objects.
• Use the display device for digitally created hand drawn art in 2D or 3D.

4. How developed is it

There are products developed for all the three types of displays, though use of multi-touch interface is by no means mainstream yet. The technology’s use is so intuitive that is bound to pick up. Any device that has a display and can be interacted with can be improved by this technology.

The two most publicized attempts for multi-touch displays are Microsoft Surface, used as a display table and iPhone, a mobile phone with multi-touch capability.

Microsoft surface is a Vista PC with a 30” display that is capable of recognising fingers and even objects using five cameras placed underneath the screen. For example, you can use a normal brush, put it into a virtual paint bucket and start drawing with it. Expect to see these devices in amusement centres for gaming, airports for VIPs and foyers of large corporation because they look impressive and cool and can keep visitors busy while they wait for their contact to arrive. Other researchers are also exploring display devices for novel applications.

Surface:

Touch screen mobile phones have been in use for years, where most popular types have been Pocket PC or Windows Mobile. iPhone’s highly publicised new feature was the ability to use more than one touch at the same time to control the device. It is an elegant solution, one that no doubt will be improved and used for years to come.

As for the vertical displays, research is undergoing and amazing demonstrations in exhibitions and conferences are capturing the public’s imagination. Perceptive Pixel has some impressive demonstration videos showcasing multi-touch on large displays.

Having seen this video, don’t you think you want to interact with computers in a truly new way? Anyway we can reduce our cognitive load when interacting with computers is a bonus, and this seems to be a step in the right direction.

There are also other attempts at developing multi-touch devices such as Lucid Touch which recognises your touch both on front and the back of a device. It doesn’t look very promising as it looks rather awkward. The dexterity and movement of fingers are heavily constrained because you need to hold the device in your hand while operating it. It is also not natural to use something from behind, so this is more of a dead-end research than a world changing one.

5. How can it be improved

There is ongoing research on using overhead cameras to detect gestures made on top of a surface, rather than touching it. This will allow you to use your hands freely in mid-air to communicate with the computer. Gestural interface is still in its infancy. Many functions can be easier and more intuitive if carried out with gestures. On the other hand, accurate interfaces such as keyboard and mouse have their own advantages, so gesture or touch based computing may not necessarily come to dominate all forms of human-machine interfaces

An obvious enhancement is to make the displays bigger and get them to recognize many more objects and touches (Microsoft Surface recognizes 50 touches at once). Ultimately you want to know how to use a new feature or application without being told how to use it, so you can just use your intuition from past experience. As computer’s advance and provide more functions to us, it becomes more critical to reduce learning curves and use efficient human-machine interfaces. Even if you are a software developer, the sheer number of applications, choices and options at your disposal is likely to overwhelm you. Intuitive interfaces are going to become more critical as the number of applications and software features are increased.

6. What does it lead to

Multi-touch will come to revolutionize the way we use computers mostly in terms of our behaviour. Some believe that these displays will be more suitable for less savvy computer users. However, as the range of applications and software complexity is increased, it will become critical to reduce our learning curves when we deal with computers in the future.

The display table will be more attractive for niche applications than the mass market. In addition, its size is a significant issue for home use. The display table must probably be placed in the middle of a living room which will take a significant amount of space and is bound to be abused by kids. Horizontal space at home has always been much more valuable than the vertical space. It’s easier to get a large vertical space in home than a horizontal one and multi-touch vertical display is a natural evolution of the monitors and TVs we use today.