Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!sample.eng.ohio-state.edu!purdue!haven.umd.edu!mimsy!tove.cs.umd.edu!sears From: sears@tove.cs.umd.edu (Andrew Sears) Newsgroups: comp.human-factors Subject: Re: Touchscreens Message-ID: <35629@mimsy.umd.edu> Date: 14 Jun 91 15:59:53 GMT References: <8435@awdprime.UUCP> <6460@ns-mx.uiowa.edu> <1991Jun13.235714.17297@cs.UAlberta.CA> Sender: news@mimsy.umd.edu Reply-To: sears@tove.cs.umd.edu (Andrew Sears) Organization: U of Maryland, Dept. of Computer Science, Coll. Pk., MD 20742 Lines: 68 I'd like to suggest to anyone who is interested in references to touchscreen research that they look at the abstracts posted by Catherine Plaisant of HCIL (where I work) in article #76. These papers contain extensive references to papers by many other researchers (the New Era in Touchscreen Applications paper has the most references). This is actually in reply to the last three postings on touchscreens. First, I have used the SAW touchscreen from Elographics (z axis). I like this technology, but I wish they would stop saying that it provides 16 levels on the Z axis when they admit only 3 or 4 are useful. Some day it would be nice to use a touchscreen that allows many levels on a Z axis. Second, having the users hand obscure the screen can be a problem if the interface is not carefully designed. It is important to remember that an interface designed for a mouse may not be optimal for a touchscreen. Of course, the users hand will still cover part of the screen, but the negative impact of this can be reduced. There have been several comments about the issue of fatigue when using the touchscreen. I'd just like to restate the experiences I've had. We have a desk that simply lets the monitor be recessed into the desk at various angles. There is a place where users can rest their forearms in front of the monitor. Placing a normal monitor in this desk so the surface is 30 degrees from horizontal dramatically reduces fatigue and increases user preference. This desk is normal in all other aspects and the monitor used is also a standard monitor. (Sears, A. (1991). Improving Touchscreen Keyboards: Design issues and a comparison with other devices. To appear in Interacting with Computers) >>Some notebook computers will not >>have a keyboard but will rely solely on a touchscreen and pen input. > >Certainly this is self-consistent. But, my handwriting is hard to read, and >after a mere year of using text editors to enter the text of papers, I >gave up composing on paper entirely. I don't want to go back. >I have also lost a significant amount of hand fitness, which makes picking >up handwriting even more of a chore. We should really make a distinction between touchscreen and pen input. Most systems that do handwriting recognition require higher resolution than is offered by touchscreens. Sure some touchscreens can be used with a stylus, but not to recognize handwriting. Personally, I do not see touchscreens being used as the input device when extensive text must be entered, the keyboard is the appropriate device for this. However, in some situations, when limited data entry is necessary, a touchscreen only interface may be useful. > >>A number of touch screens do not actually require that their surface be >>touched but humans seem to love to jam their fingertips forward. > >This is because constrained selection is easier than unconstrained >selection. Using a 3D technique to select a 2D object is silly. >The tactile feedback is useful, also. > Selection of buttons can work very well on touchscreens. Appropriate feedback at the appropriate time can make this very easy to learn and use. Andrew ----------------------------------------------------------------------------- Andrew Sears sears@CS.umd.edu Human-Computer Interaction Laboratory University of Maryland, College Park, MD 20742 (301) 405-2725