bobm@anasaz.UUCP (Bob Maccione) (08/22/90)
speaking of removing the backing on LCDs and projecting light through them. Has anybody tried to make a heads up display that way? Something that could be fitted to a helmet or added to glasses. Also has anybody seen sources or built a helmet camera? I'd like to attach some type of color camera ( with the tape mounted remotly ) to my windsurfing/motorcycle helmet and make videos. Any suggestions? thanks bob
maj@hpfinote.HP.COM (Mike Jassowski) (08/25/90)
speaking of removing the backing on LCDs and projecting light through them. Has anybody tried to make a heads up display that way? Something that could be fitted to a helmet or added to glasses. ---------- Heads up displays are useful because they are virtual images focused at infinity. You don't have to refocus your eyes when you look from a distant object to the display, and can therefore read the information faster. Having a LCD a few inches from your face will be difficult to even focus on, much less focus quickly. --Mike
cgordon@vpnet.chi.il.us (Gordon Hlavenka) (08/29/90)
>speaking of removing the backing on LCDs and projecting light through >them. Has anybody tried to make a heads up display that way? Something >that could be fitted to a helmet or added to glasses. This probably wouldn't work well, as you'd have to shift your focus between the display and the world. Try reading something two inches in front of you... True heads-up displays have their focus at infinity, so they are easily readable. ----------------------------------------------------- Gordon S. Hlavenka cgordon@vpnet.chi.il.us
fmgst@unix.cis.pitt.edu (Filip Gieszczykiewicz) (08/29/90)
`>speaking of removing the backing on LCDs and projecting light through `>them. Has anybody tried to make a heads up display that way? Something `>that could be fitted to a helmet or added to glasses. ` `This probably wouldn't work well, as you'd have to shift your focus between `the display and the world. Try reading something two inches in front of `you... True heads-up displays have their focus at infinity, so they are `easily readable. Greetings. And how does the "focus at infinity" work? I presume you would need lenses - acrylic as to not have 40 lbs on you head? Hey, you might as well explain - I already took the LCD out of the TV. Now what? ;-) ` `----------------------------------------------------- `Gordon S. Hlavenka cgordon@vpnet.chi.il.us Take care. -- _______________________________________________________________________________ "The Force will be with you, always." It _is_ with me and has been for 10 years Filip Gieszczykiewicz "A man without a dream is like a fish without water." FMGST@PITTVMS or fmgst@unix.cis.pitt.edu "My ideas. ALL MINE!!"
mwtilden@watmath.waterloo.edu (M.W.Tilden, Hardware) (08/29/90)
In article <26da9f56-37c.5sci.electronics-1@vpnet.chi.il.us> cgordon@vpnet.chi.il.us (Gordon Hlavenka) writes: > >>speaking of removing the backing on LCDs and projecting light through >>them. Has anybody tried to make a heads up display that way? Something >>that could be fitted to a helmet or added to glasses. > >This probably wouldn't work well, as you'd have to shift your focus between >the display and the world. Try reading something two inches in front of >you... True heads-up displays have their focus at infinity, so they are >easily readable. To use LCDs as a heads-up, it's better to mount the displays somewhere about the ears and project them into the eyes by a partially reflective window. This avoids the problem of excessive weight and balance distribution. A lens assembly still must be added to change depth perception, but it can be significantly simpler and helmet mounted. Having the units around the ears also centralizes all connection electronics thus reducing fatigue problems in the circuitry (a major problem in any body-mounted electronics). As an added feature, you would want the reflection/view planes LCD polarizable so you could 'cut off' the outside world as easy as you adjust the contrast on your LCD image. This will allow you to balance the intensity of both real and virtual images dynamically. Is all. -- Mark Tilden: _-_-_-__--__--_ /(glitch!) M.F.C.F Hardware Design Lab. -_-___ | \ /\/ U of Waterloo. Ont. Can, N2L-3G1 |__-_-_-| \/ (519) - 885 - 1211 ext.2454, "MY OPINIONS, YOU HEAR!? MINE! MINE! MINE! MINE! MINE! AH HAHAHAHAHAHAHAHAHA!!"
greg@bluemtn.uucp (Greg Richter (2XS)) (08/30/90)
> > Greetings. And how does the "focus at infinity" work? > I presume you would need lenses - acrylic as to not > have 40 lbs on you head? Gordo - You have to put a lens or so in front of it, typically a cylindrical lens. The LCD is going to be a little dim, and the resolution sucks. Try a crt display projected on a visor ala Honeywell, or the Private Eye from Refelct Tech. CRT works, is easy and can be done cheap. The Private Eye resolution is not that great, but it is usable for a HUD. I fly with one. - Greg -- A fly can't bird but a bird can fly - | Ask me a question and I reply, | Cottleston Cottleston Cottleston Pie! | Greg Richter | {emory,gatech}!bluemtn!greg
maj@hpfinote.HP.COM (Mike Jassowski) (08/31/90)
Greetings. And how does the "focus at infinity" work? I presume you would need lenses - acrylic as to not have 40 lbs on you head? ---------- I imagine you are asking how a heads up display focuses at infinity without a bunch of lenses? I had a holography class which discussed this many years ago. They used a projector with a holographic lens to project the images onto the cockpit windshield with an apparent focus of infinity. I'd imagine that there is some pretty good literature on this available for more detail on specifications for the holographic lens. -- Mike Jassowski
heskett@titan.tsd.arlut.utexas.edu (Donald Heskett) (09/17/90)
In article <15880016@hpfinote.HP.COM> maj@hpfinote.HP.COM (Mike Jassowski) writes: > speaking of removing the backing on LCDs and projecting light through > them. Has anybody tried to make a heads up display that way? Something > that could be fitted to a helmet or added to glasses. ---------- >> Heads up displays are useful because they are virtual images focused >> at infinity. You don't have to refocus your eyes when you look from a >> distant object to the display, and can therefore read the information >> faster. Having a LCD a few inches from your face will be difficult to >> even focus on, much less focus quickly. Putting the proper optics, properly focused, between the eyes and LCD screen would allow the image of the screen to be in focus and the screen to appear to be at infinity. The ordinary use of a simple magnifying glass works in almost this fashion; for the suggested application, of course, you would want to use high quality optics instead of a simple magnifying glass, but the principle is the same.