"And then you might want to do some fine tuning and tweaking with more detailed analysis," says Garimella. Chapter The Critical Last Inch-Input and Output Technologies The telecom world spends a lot of time thinking about the "last mile"-that critical distance between the customer and the service provider's equipment. Yet, for a growing number of telecom device manufacturers (and their cus- tomers), the really important factor limiting the use of telecom technology is the "last inch"-the distance that separates the user's finger from a keyboard or keypad and the user's eye from a display screen. As telecom devices shrink, "last inch" design issues are becoming increas- ingly critical. For example, how do you allow people to input alphanumeric data into a button-sized PDA? And, conversely, how does one mount a screen that can display meaningful information on a device that's no larger than a thumbnail? Researchers around the world are pondering the growing input/ output problem and are arriving at an array of potential solutions. 9.1 A FINGER PHONE Mobile phone manufacturers are beginning to experiment with novel phone form factors in an attempt to better address users' daily needs. Japan's NTT DoCoMo, for instance, is developing a radically new type of mobile phone that uses the human hand as an integral part of the receiver. The Finger Whisper, which is being developed at NTT DoCoMo's Yokosuka, Japan, R&D center, works by requiring its user to stick a finger into his or her ear. Telecosmos: The Next Great Telecom Revolution, edited by John Edwards ISBN 0-471-65533-3 Copyright © 2005 by John Wiley & Sons, Inc. VOICE INPUT The watch-like terminal, which is worn on the wrist, converts voice to vibra- tion through an electromechanical actuator. It then channels the vibrations through the hand's bones to the tip of the user's index finger. By inserting this finger into the ear canal, the vibration can be heard as sound. Because the microphone is located on the inner side of the wrist, the posture of the user's hand w