Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site utcsri.UUCP Path: utzoo!utcsri!greg From: greg@utcsri.UUCP (Gregory Smith) Newsgroups: sci.electronics Subject: Re: Heads up display for a motorcycle helmet Message-ID: <4322@utcsri.UUCP> Date: Fri, 6-Mar-87 15:08:19 EST Article-I.D.: utcsri.4322 Posted: Fri Mar 6 15:08:19 1987 Date-Received: Sat, 7-Mar-87 04:42:25 EST References: <3610001@hpfcpp.HP.COM> <492@oucs.cs.OHIOU.EDU> <1831@vax3.tc.fluke.COM> Reply-To: greg@utcsri.UUCP (Gregory Smith) Organization: CSRI, University of Toronto Lines: 44 Summary: In article <1831@vax3.tc.fluke.COM> szepesi@fluke.UUCP writes: >From what I remember of my experiences in school, I believe the device you >are referring to locates the direction the eyes are pointing, not the distance >to which they are focused. In a physiology lab I was in, we did some visual >perception experiments that used an infrared emitter that was aimed at the >boundary between the iris and the sclera (the colored and white parts of the >eye. The amount of IR reflected varys between these two portions of the eye, >and by detecting an increase or decrease in response, a detector is able to >tell which direction the eye moves. Extending this to more than one direction >is possible with more than one emitter/detector pair. > >Getting this to be auto-adjustable for a helmet seems to be a real pain. The >setup we used required a fair amount of adjusting and was easily knocked out >of alignment. > >Les Szepesi A helmet HUD would automatically follow head motion. Why would you want it to follow eye motion? If the display kept its center where your eyes were looking, you wouldn't be able to look at any part except the center. It would be like trying to look at an afterimage in the corner of your eye. Of course you could do something clever like select different displays depending on where you looked, but I think that would be intensely annoying. Eye movement is not really a conscious action; we look at objects, and our eyes stay on those objects independantly of head motion. Thus the movement of the eye relative to the head is not really consciously controlled. So using it to control anything is probably a mistake. Head motion is a far more conscious action. [The preceding paragraph is based on my own guess and not on anyone's psychological research] Besides, with a HUD that followed the head, one could keep one's eyes pointing at a distant object, and simultaneously bring the desired part of the HUD onto the same point by head rotation. As someone pointed out, the HUD is focused at infinity and there is no real difference between focusing one's eyes at infinity, and focusing at 'outdoors' distances. -- ---------------------------------------------------------------------- Greg Smith University of Toronto UUCP: ..utzoo!utcsri!greg Have vAX, will hack...