Re: Behind the screen.

[T3D Larry Berlin <lberlin@xxxxxxxxx>]

>Date: Fri, 13 Dec 1996 17:58:54 -0800
>From: T3D Jose asks:
>
>Dear 3Ders,
>           I made a presentation on applications of my diffractive 
>screens at SHARP in Tokyo, referring my point of view on the 
>limitations os stereo 3D images.
>My claim is that it will never be possible to show 3D without 
>goggles to more than one observer at a time, due to the lack of 
>continuity on the transition between viewpoints.

************  Interesting premise.

>And that the scene will also never be seen in full depth.

************  What is meant by *full depth*? I'm acquainted with stereo
scenes and consider that I've seen the *full depth* but I think I don't
understand your reference here.

>An executive ask me then if it would be possible to see images 
>behind the screen because stereo can not do that.

************ Stereo most certainly does have that capability. Again, perhaps
I'm not understanding you but I look at 3D behind the screen and in front of
the screen all the time and it seems fairly normal for 3D imaging to be in
either place. That's what 3D is all about, not being limited to the screen
itself.

>
>I answered that I do not know about stereo (in fact, I always saw 
>images in front of the screen, never a person or car goin deep 
>behind) but that I did images more than 30m behind the diffractive 
>screen, and maybe more would be possible.
>
>Can you tell me about the possibility of putting an object in a 
>stereo scene, in a movie f.ex., going behind the screen?.

*************  Visit my web pages or many of the other web pages of P3D and
T3D members who have a large variety of images and presentations. Generally,
if the stereo image is being viewed in a parallel viewing method, it exists
behind the screen and if you view with crossed technique it is in front of
the screen. The use of the new interlaced tehcnology makes it possible to
place the stereo image on the whole screen instead of using side by side
pairs. I'm sure there is a lot of latitude for design in which you can do
both in front of and behind the screen.

>
>By the way, let me comment that SHARP has a very nice show room there 
>and, although they mention 3D as images for the utopic future, they 
>do not even show there the experimental 3Dgoggless TV made by SHARP 
>in England.  I received a description of this, and saw another setup
>in another exhibit working under not the same but more or less similar 
>principles.

***************  Typical one-eyed thinking even on the part of companies
supposedly working on 3D technology. 3D goggles are here at last and they
don't need a special TV to be used. They work on both the TV set or the
computer monitor, with better performance on the monitor. If they aren't
talking about it it's because they aren't a part of what's happening.

>
>SHARP model uses Fresnel almost plane lenses.............

****************  So far all lenticular systems have a greater problem with
depth and a limited number of depth layers available. This is why interlaced
goggles will have a market advantage for quite some time. Then the laser
scanning systems that project the image directly into the eye will have a
good chance to exceed whatever lenticulars may accomplish. If anyone is
going to do something with lenticulars I wish they'd get on with it since
it's been around a long time and reliable demonstrations do exist. The only
explanation is that no one has been convinced enough to spend the money for
product development, but there are some options currently being developed
which claim to offer a reasonably full 3D experience to a number of users in
front of a monitor, or can be used in a theater for a whole crowd. I'd like
the chance to view such a thing.

>
>I could not visit SANYO, who is the only one selling a 3D goggless 
>TV system. I was affected by cold air when presenting a paper in 
>Nanjing, China, a very hot and humid place in summer but with powerful 
>air conditioning machines directed towards the privilegiated speaker.

*************  There are numerous companies making and selling goggle
systems. The one that looks the best at this point is the VR Surfer from
VRex Company in N.Y. If you want something relatively cheap, one mfg.
(Cybershades ?) is going out of the goggle business and their system is
selling for $35, but it's now considered obsolete though it works well. By
this time next year, all available systems will be less expensive and more
available.

>
>All this above is an excuse to tell you about what SHARP really shows 
>which, although is not 3D, it is worth to know.
>They have a not too large cinema (about 300 seats) in the show room 
>with three liquid crystal projectors supperposing images to bring 
>HHDTV. (The double HH = Higly High is my conceptuation, I do not know 
>which name they give to this incredible images).
>Not only definition, but the color quality, makes you to want more of
>that, and no more ordinary movies.

*************  Sounds good! When they demonstrate it for 3D projection I'll
be impressed. There are LCD 3D projection systems in existence now but they
are expensive. I'm sure this HHDTV will be adaptable to the stereo system if
they choose to think other than flatly.

Larry Berlin

Email: lberlin@xxxxxxxxx
http://www.sonic.net/~lberlin/
http://3dzine.simplenet.com/


------------------------------

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