At Sun, 3 Jul 2011 04:30:37 +0100 CentOS mailing list <centos@centos.org> wrote:
> > On Sunday 03 July 2011 00:51:29 Robert Heller wrote: > > > > There is (in the SciFi world) the idea that someday > > > > 'desktops' in the current / conventional sense may completely vanish > > > > from the universe, taken over progressably by laptops, tablets, smart > > > > phones, wearable computers (motherboard == shirt, monitor == shades, > > > > power supply == hat with embedded solar cells, virtual mouse/keyboard > > > > via motion sensors in your shirt sleves/gloves, etc.), > > > > > > I could in principle imagine all that coming in the future, but the > > > "monitor == shades" thing is just only Fi with no Sci in it. A human eye > > > cannot focus properly on any object which is closer to the eye than 10-15 > > > cm (depending on the eye quality), so there is absolutely no way one can > > > use shades or contact lenses or something similar as a monitor, > > > regardless of technological levels of any human or alien races (James > > > Bond notwithstanding). Unless of course one surgically adapts the eye > > > lense itself, in which case the person would not be able to see anything > > > else... ;-) > > > > Hmmm... There were a CS prof. and some students at UMass when I was > > working there playing with a computer in a backpack with a 1" monitor > > suspended from a head mount in front of one eye. Not anything like > > 10-15 cm. If 10-15 cm is the minimum distance, what about telescope > > eyepieces, camera viewfinders (including the little video ones on > > camcorders), or binoculars? *I* know I can see images in the video > > viewfinder of my Sony Hi8 camcorder just fine, with my right up close > > (the old camcorder I have does NOT have a 3" swing out monitor). It is > > all about the optics. > > I wouldn't know about that CS prof. at UMass. Have any info that can point me > to him? Other examples you mention all have to do with lenses that twist the > trajectory of light to make distant or small things visible. When using > telescopes, binoculars, camera viewfinders, microscopes, and other stuff like > that, you are actually looking *through* a (transparent) device to see > something else outside, you're never looking *at* a device, or something that > is inside it. I don't remember who was doing the experiements. It would likely be a 1" camcorder viewfinder 'monitor', that is designed to be right up against one's eye. > > In contrast to that, actually drawing a picture which is 1-2cm away from the > eye is a completely different game. Just take a piece of paper, draw > something > on it and put it 2 cm in front of your eye. The drawing will get blurred. And > it's not because you used a thick pen, but because the eye lens cannot focus > on such a short distance. > > Now, you might consider putting some convenient lenses between the paper and > the eye, to fix that problem. I don't have time do actually do the > calculation > of the properties of such a lens, but it's an interesting problem in > geometric > optics. You would want a convex lens that moves the focal point of the eye > from 15 cm to 2 cm. The trick is to find a transparent material which would > have a refraction index high enough that it can do what you want, while still > be thin enough to fit between the monitor and the eye (ie. it needs to be > thinner than 2 cm). I don't know if ordinary glass or any other material > would > do that or not. But it could be an interesting exercise for a student of > geometric optics. :-) > > The bigger issue is the fact that, even if you manage to find an appropriate > lens to move the focal point to 2 cm, it is going to distort everything else > you see behind it. In principle you could devote one eye for the > monitor-only, > making the whole apparatus non-transparent, and use the other eye for the > outside world. That would, however, destroy the 3D vision of both the outside > world and eventual monitor 3D picture (because you can wear it only on one > eye). > > Actually, now that I think more and more about it, I am not so sure it is not > doable. However, it is far from being trivial, and it certainly cannot be > something that can be as thin as ordinary shades. It has to be bulky and > heavy > (due to the optics inside) and is bound to impair your vision of the real > world. > > If I get some free time, I might even try to calculate the properties of such > a system of lenses, but I'm skeptic that the cool "monitor-shades" will ever > be possible. ;-) OTOH, I would expect that people in the 1890's would consider the Apollo Moon landings as 'impossible'... So, given enough advances in optics and monitor techology: LCD screens that can switch to complete transparency or to varying levels of transparency, and things like programmable lenses / optical systems, it becomes concievable. > > But now we are getting quite OT here... ;-) > > Best, :-) > Marko > > _______________________________________________ > CentOS mailing list > CentOS@centos.org > http://lists.centos.org/mailman/listinfo/centos > > > -- Robert Heller -- 978-544-6933 / hel...@deepsoft.com Deepwoods Software -- http://www.deepsoft.com/ () ascii ribbon campaign -- against html e-mail /\ www.asciiribbon.org -- against proprietary attachments _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
