[DIY] Dual LCD Polarized display for Cheap!

[nubie]

I found an excellent source for the mirror needed to do something like this:

http://www.planar.com/products/flatpanel_m...opic/SD1710.cfm

Here is a pic of the original Cobox by Mr. Co van Ekeren from the Netherlands, this is what inspired Mr. Barry Aldous to make the Tardis (link).

http://home.hetnet.nl/mr_2/25/wolkers19 ... dcube1.jpg

As you can see, this is a Very bright and high-contrast method for 3D.

They want $4,000 for the Planar setup, whereas the exact same monitors used to make it are about $120 apiece in good used condition on eBay. If you are already using an LCD monitor, get a second identical unit, so you already are halfway there as you read this .

EDIT: these are of inferior quality and made of plastic, better to find a local glass shop and ask them for what you need. http://www.telepromptermirrors.com/ has a service that provides the half-silvered mirrors (they pass half the light through them, and reflect half the light off of them) for a good price.

I bought a 15" by 15" piece on eBay for $82 after shipping (ouch).

When I recieved the mirror I did some measurements and discovered I could probably get by with a 15"x10" and they are $40 on the custom calculator, of course that is before shipping, but they ship USPS under 15x15 anyway, so it should be inexpensive, about $10.

So be warned, use their custom sizes for your project, it is much less expensive.

To do a quick mock-up use a piece of cardboard or paper of the size you want to order, hold it where the mirror is in the Planar setup as you sit in your normal viewing position in front of your monitor, try to get a 45? angle or so out of the paper/cardboard. Then check if you can still see the screen, if the answer is no, then it is a good size to use, get a couple extra inches to be safe. The mirror will allow you to see the LCD display like normal, with the reflection of the second LCD overlayed on top of it.

I use a Planar PE171 that I got on ebay for $45 plus shipping ($15), so I am doing well so far, now I need the second monitor to arrive.

All you need is the above mentioned 2 LCD displays, be creative, 15" is fine on a budget (you can get them from people upgrading a Dell/Gateway/Emachines/HP bundled LCD display) 19" Widescreen, even 24", 30" or 50" should be possible, start with a smaller/cheaper "proof of concept" edition and then move up to the big leagues, remember that you will need a video card capable of driving the panels in native resolution for the games you want to play at an acceptable frame-rate (unless your monitor will show 1:1 with a black border on lower than native resolutions). With dual 1280x1024 17" panels that makes 2560x1024 pixels per frame, or 1280x2048, depending on how you look at it.

Basically any size LCD screen will work, as long as it is 45° polarized, get some cheap glasses from here: http://www.berezin.com/3d/3dglasses.htm#Polarized ($2 for 3, $6 for 10) and see if yours is, one eye will be dark as you look at the LCD, the other eye will remain clear.

As you put the LCD's in the Planar arrangement shown above with a mirror (even plain glass could be used, ask a glass store for a scrap, it just will not be as reflective), the LCD that reflects off of the glass switches polarization by 90? and will be visible in one lens, while the other will not see it.

So there you have it, do some scrounging and some shopping and enjoy true flicker-free, always on 3D that you can share with a friend (remember the 3-pack of glasses?).

Hopefully I can get some pictures if/when I ever get this digital camera wrangled into shape (I bought a Fujifilm A330 that needs a firmware upgrade to use the M or H xD cards. I bought a 512MB xD H card and now I need a standard card to flash the firmware upgrade into it. I looked all over town and "regular" xD cards don't exist anymore in the retail stores, so I ordered a 16MB off of ebay for $4 , if that ever makes it I should be doing good.)

On a side note polarized glasses work great and are not uncomfortable in any way, they also do not have batteries, IR sensors or cords. The contrast is very deep, much deeper than shutter glasses, and they are clearer than sutter glasses are when off. Obviously you need a second monitor and some special glass, but those are so cheap in price that it isn't worth arguing over considering what you get in comparison.

[dayhu]

If you are buying new monitors make sure the polarization of the monitors is 45 /135 degrees Some monitors have polarization at 90 or 180 degrees These will not work Here is another source for the half mirror www.teleprompterglass.com It is a lot more expensive but is glass and not acrylic In a comparision of small sample from both suppliers the glass seemed much preferable I have however put this project on hold until I receive my iz3d monitor

[Freke1]

Hi, I was just wondering if You get twice the framerate of shutterglasses?

[zebrastealer]

I received the polarized glasses today, hopefully the reflective glass comes tomorrow and I can do some actual tests. Quick question though - I tried both pairs of polarized glasses out (one terminator style, and one generic style). With both pair of glasses I could still see some of the monitor output through the one lens of the polarized glasses. Granted it wasn't as visible as the other eye. The genric set mostly blocked the monitor output out of that one eye, but there was still a faint image present. Is this normal or does it indicate my monitor has a different polarization angle? Do you think this will affect the 3d effect or will I be dealing with bad ghosting? Any suggestions for me?

Thanks guys.

George

[dayhu]

There will be some ghosting , even more when you use the mirror. To confirm the polarisation of the monitor Rotate the glasses while looking at the monitor thru one side or the other At one point the lens should be almost completely opaque Hopefully this should be normal angle at which the glasses are used

[nubie]

Ghosting is going to happen, but the overall contrast between "off" and "on" is going to be as good or better than shutter-glasses.

I think the ghosting will be less with the mirror, since it drops the light by 50% (half reflective/half transmissive).

The Terminator style might be a little out of alignment, try rotating the glasses slightly and find the darkest spot. Then do the same with the generics, is there a perceptable difference?

Are the Terminators curved? that may make the polarization effect lessened. Are your "generics" the $3 plastic or the cheaper paper frames?

For a really nice set of glasses I am going to make them out of the 3"x3" squares of polarizing material that Berezin3d.com has ($15 for a pair), as even my $3 plastic glasses seem to have cheap flexible polarizer, not of the highest quality.

I only notice ghosting when there are bright points of light in the game, for example car headlights or a fire in the dark, it is possible to lessen this by reducing the contrast setting and checking your glasses. Maybe it would even go away with 2 pairs of glasses on, but that probably would make it too hard to see.

On the topic of the glass, telepromptermirrors.com sells plastic (acrylic) ones, while cheap and durable (against breakage), they will probably scratch easily and they seem to have a strange pattern too them.

You may want to contact the teleprompterglass.com guy and see if his glass is of higher quality if you want to build this for a high-end rig. For a budget-build I am finding the acrylic works fine.

I have pictures, I haven't got them uploaded anywhere yet, so I can't show them. I went with the 2x4 and plywood route, with 2 aluminum straps to connect the mounting pads on the back of the LCD's with the 2x4. I used a bit of solid copper insulated building wiring to hold up the mirror, it functions to a point.

Alternatively, get a piece of square tubing and have it bent or welded at a 90? to 110? angle. Then use these pads to connect your screens to the tubing: http://www.monoprice.com/products/produ ... t=2&style=

$3.65 apiece for 2 and you have a monitor mount ready, just make a "foot" for the square tube that will withstand the weight of your monitor hanging up there and you are ready to desing a bracket for your mirror.

[windelfried]

hallo,

nice to read, that several people also building up planar type monitors.

i builded a small planar type monitor last year in dezember for
foto + video purposes.
2 x nec 6.3'' 1024 x 768 - pal is upscaling to 1024 x 768 pixel !!!!
i also included a faroudja deinterlacer for video in ... looks really great !!!

my monitor has got
composite / svideo / component / dvi /vga imputs .. ( each panel )
now i can connect two cameras to my setting and i can see the stereoscopic picture while shooting photos or videos ...
it is working really great.

now i can change the stereobase while watching the result .
i can re-adjust wrong zoom or other wrong settings of the cameras online.
( 2x canon 400D / 2xSony dcrhc96)


now i'm currently working on a planar type setting with
2 samsung 27'' ( 275t) panels for gaming.
i think this could be a field of view of round about 70? !!!!

i hope this will be as good as in my dreams.


i hope to show some results within the next two weeks.

windelfried

[Likay]

Just curious. Is there any way of finding out the polarisation angle for LCD-screens before bying? The one i have now have straight 90? polarisation. I have a dual projector setup now but i am a little bit curious about a planar design with TFT's (if not else i really like the innovative aspect).

[Jahun]

Likay, not sure if I understand you correctly, but since you already also had cheap (non-spar) polarizers, you can just take those to a shop?

Or take your polarizer glasses with you..

If you mean from a webshop, no clue.

[Likay]

Hehe. think this got mixed up with the other thread when i was talking about projectors.
In this thread i'm asking if anybody knows ho to get the polarisation angle for LCD-monitors. When asking resellers i get an answer type: "Polarisation angle? I'm not really sure what you're talking about but i assure you we'we got a monitor that perfectly suits your needs bla bla". Also downloaded some pdf's but haven't found one yet with those kind of data...
Regarding those cheap polarizers i know the storekeeper and he also knows about my experiments with polarization. You can say i practically had those cheap camerapolarizers for free. He already knows it doesn't work and i didn't bothered with them anymore. What bother me more is that one of the SPARS gave up only after 35 hours of projection. Mailed Silverfabric this fridag about the problem. In worst case i have to wait those 21 days of production again. Let see what happen.

Cheers

[windelfried]

hallo likay ...

if you have two 90? or 0? panels planar setup will not work.

but you can change the polarization of the panels very easy.

1.
you can buy one retarder foil ( lambda/2). you can change the polarization of on panel e.g. from e.g. 0? to 90?.
(look at optigrafix.com)
then you will need 0?/90? glasses.

2.
the other method is, you will have to use two polarisation foils with 45? to change the polarization angle to 45? for both panels.
but you will loose some additional light, but it is working for me.

in this case you can use the 45? / 135 ? polarization glasses.

my 27" samsung 275T planar setting has got 0? polarisation.
and i'm currently changing the polarization with polarization foils to 45? (2).

later i will use the retarder (1). - i'm curretly searching for retarder foil reseller in germany.

i'm also thinking about mirror foils.




windelfried

[Jahun]

Hmm Likay I meant that.. I think

I mean.. I assume you got some store in your area that does sell those specific monitors too, and you do own a set of polarizers of which you know the polarizing axis. Then you can just walk up to the monitor you are interested in, and look through your polarizers and check?

If the polarizers are at an angle of 45 degrees compared to the monitors to either block or fully let light through, the monitors are fine..

Or did I manage to miss something again ?
That's how I check my projector, but it goes for any lightsource I suppose...


Too bad to hear about that SPAR filter btw, I sure hope you get a replacement. Sounds very odd that it died on you that quickly How close is it to the lense of your beamer?


Ow and aren't retarder foils a bit color sensitive? Different wavelengths would react differently I'd say...

[Likay]

Ok. Was really hoping to get monitors with either 45 or 135? of polarization since the mirror handles the rest and without loosing so much light. I'm checking the site out and requesting pricelist. Have searched for resellers for such stuffs here in sweden too but it's quite difficult. Haven't consulted my local camerastorekeeper yet. Perhaps he knows some about getting polarized films at a more local place. Anyway: Thank you. Haven't decided to build a planar device yet but i'm sure interrested!.

Jahun: Ok, now i get you. There's no good resellers about here with good computer equipment, but the idea of bringing the glasses is sure not stupid!
Actually gonna give it a shot at the big city when i get over there.
The SPARS are made to be placed at a distance of 2-3 cm from the lense of the beamer. They are also designed to handle projectors with an output of 5000 AnsiLumen. However the projector design doesn't allow me to put them that close so the distance i used was about 5-6 cm. Should be no problem there...
What i think happened is that the glue between the glass-pieces somehow didn't harden correct and now there's some air between the glass-pieces resulting in a blurry picture. Too bad since the performance of the filters otherways is outstanding. However i have no problem to settle with standard polarizers but why should i do that now? hehe. But i get some answers tomorrow i guess.

edit: Regarding the spars: It ws probably the glue that hadn't hardened correctly. They replaced it without any cost for me and also send 10 pair extra glasses.

cheers

[Jaydee]

I am having the same problem with my Dell 2005FPW screens, they are polarised at 0 degrees. I've just bought two 17" polarizing filters which are at 45 degrees from http://www.3dlens.com/shop/polarizer.php for about $60 which to me is about ?30, including p&p. This should fix my problems and allow me to view in 3d!

[gamma]

hi

I recently read the document "Optimal Usage of LCD Projectors for Polarised Stereoscopic Projection" by Andrew J. Woods
http://www.cmst.curtin.edu.au/publicat/2001-01.pdf

He explains using a half-wave plate between the LCD and linear polariser(figure 3) to retain more light output:
"it is desirable that the bulk of the light being output by the projectors in the vertically polarised direction be
rotated into the desired +45? or -45? orientations ? this can be achieved with a ? wave retarder. Linear polarisers are then
placed at the output to purify the linear polarisation in the desired directions"

Apparently cellophane makes a decent half wave plate.

[nubie]

Cool, I updated the forums.nvidia thread, but I didn't here.

I built a new rig to hold the screen and the mirror with Wood, angle brackets, threaded rod, and some angle stock.

http://picasaweb.google.com/nubie07/Ste ... 7970053378

This is a whole gallery of the new stand. The top monitor is having backlight issues, one of the fluorescent tubes may have died.

[The_Doctor]

How does the ghosting of the planar setup compare to the iz3d monitor? More, less? What about with crt and shutterglasses?

[nubie]

I notice nearly no ghosting (I have seen it, but usually it is on the edge of a building in shadow with a bright sky beside it, and I am not sure if that is due to my warped acrylic mirror or the glasses being askew on my head.)

I haven't yet tried a glass mirror, but I can clearly see the warp in my acrylic as a ghost pattern through my polarizer.

I haven't tried an iZ3D, so I can't really say.

As for CRT, there is absolutely no comparison, this is near perfect, and it can't switch eyes on you or lose synch as a bonus.

I would say 2 to 10 times as much contrast easily, and no flickering (I can't stand any flicker, even a standard monitor at 60hz will give me rioting headaches.)
It is a trifle dependent on your iris level, so if you were gaming in an entirely dark room you would see more ghosting, but I just have a 60-watt bulb on and it is nearly 100% because my iris is compensating for the ambient light. Fun fact, your eye is sensitive enough to catch a single photon of light, this makes it pretty tough to fool


If you wanted to set up a front-surface mirror and a pair of any type of monitor for direct view, see here http://www.crystalcanyons.net/pages/Tec ... ewing.shtm

This method has you look at one monitor directly, and use a standard mirror (or a front surface mirror) on your other eye to look at the second screen. I have thought of using this to make a franken-HMD, possibly mounted on an eye-level shelf with a movable chair, or a floating helmet supported by some sort of arm or chain to the ceiling. There are 10"-14" LCD screens that are 1280x768 or 1900x1200, and you could make quite the helmet rig with couple of those.

[winch8]

I've just bought a pair of paper glasses linearly (45/135) polarized. I discovered that my acer 1916w lcd monotor (19" widescreen) is polarized at 45° because
when i wear those glasses my right eye sees the scrren almost black while the left eye sees the scrren almost normaly bright. But i noticed also that i need some
light behind myself that hits the monitor becasue otherwise the right lens can't block too much of the screen light and this would surely cause severe ghosting on
a planar setup. Plus if you tilt your head even by very little margin the blocking filter begins to let more screen image to pass trough (ghosting would be assured), and if you
tilt your head a little more the screen image becomes too much visible to the right eye and you would simply loose the 3d effect and see a double image.
Real D 3d movies at the cinema like beowulf use circular polarization and also imax 3d theaters use circular polarization...i think itì's the only really effective and
comfortable way to see 3d, apart from shutter glasses with high refresh rates screens (but they don't work fine anyway on lcd monitors).

[nubie]

You are correct of course, and if you wanted to purchase circular polarizing material and put it over the screens you could, and then you wouldn't have that problem. This is a big step up from direct-mirrored, you can move around and all you need to do is keep your head level, which I usually do when I am on the PC.

I would almost rather buy an iZ3D or Zalman than get circular polarization, but I would want to test drive them first to see exactly what it was like (especially using a non-native pixel perfect resolution on that Zalman to see if the effect still works, some games have zero support for custom resolutions or non 4:3 displays).

I would really like a dual DLP projection rig with circular polarizers, then there wouldn't be any problem with tilting of the head.

[winch8]

Mmmmmm...putting circular polarized glasses over the screens...i read that circular polarized light CANNOT be reflected by mirrors so the half mirror could not reflect the
image of the second monitor. Do you know if it is true?

[winch8]

I am thinking that the new polarized glasses promised by iz3d could solve this problem!
In fact if, put the case, they are a sort of multiple linear polarized glasses, meaning that one filter
blocks all light polarized between 0°-90° and lets pass all light polarized between 90°-180 and the other filter
viceversa, the polarized light of lcd monitors would be filtered much better just like circular polarization!
Standard linear polarization is useful for applications like photograpy but the one i hypothesize is much
better for stereo 3d...
Do you think it is possible?

[nubie]

I don't know, I would rather have a mitsubishi 3D DLP for around $1600 at 60 inches!! http://www.amazon.com/Mitsubishi-WD-607 ... B00166BNFS

[distantreader]

I had couple of Dell 2407WFPp but for the life of me searching on the net for their polarization characteristics still couldn't find out, none of the specs I've seen mention this characteristic, just hoping someone in this forum might know what it is? (I'm hoping they are 45 degree to make my life easier), contemplating of putting them into a planar setup and in the "researching" phase in hope of a better S3D experience than CRT/shutterglasses. Any help is appreciated.

EDIT: using my shutterglasses with normal position I can see the screen of the LCD, tilt the glasses 45 degree and it's almost black. With the shutterglasses at 90 degree it's clear again. So even this doesn't tell the polarization angle of the Dell's (since I don't know the polarization angle of the shutterglasses, I assume the pol. angle of the shutterglasses are the same as that of the polarized glasses that people used in their planar setup ?), is it safe to say the Dell's are polarized at 45 degree ?

EDIT2: Tried the shutter glasses with my laptop LCD and found that with normal horizontal position it's black and in perpendicular position it becomes clear so I think the best way is to buy a pair of polarized glasses and test it with the Dell's LCD to make sure it works/or not and if the 45 degree glasses don't work with the Dells then I should be able to try the 90 degree ones, I hope they do exist.

[StereoGaming4Me]

I'm about 98% complete with my dual acer 20" planar cube.. was wondering about convergence settings in the old nvidia cp but the other thread helped out there. The last thing I'm trying to figure out to make the planar complete is whether or not my top lcd needs the brightness and contrast to have higher luminance than the back lcd. On the XP desktop I still get a horiztonally flipped image from the top lcd until I engage a game - then the top lcd flips horizontally after DX9 is implemented.

Should the back lcd or top lcd be brighter and higher in contrast for tweaking convergence and separation, since that is the final step here and I haven't had a lot of time to do any testing?

Thank you to anyone who can offer advice! Have a great day!

[StereoGaming4Me]

Hey nubie.. how are you?

I was wondering about the pop out effect with this.. mine is set up correctly and plays a good number of games but if there is any pop out it somewhat just shows at the front of the cube at a seemingly closer distance to your eyes. If a bracket method is used, does any kind of light become a big problem anywhere along the line with reflections and shadows anywhere? I'm asking because in the dark and with a bracket where you can't notice the glass too much that perhaps the S3D effect does appear to pop out from the screen into thin air as well as depth... because mine is like looking into an lcd monitor almost 2 feet deep with a very compatible game. I would think with a bracket you would have a neat holographic pop out effect in pitch dark, but another post mentioned something about needing a little light so the pupils do not dilate to reduce crosstalk.

It would be great to hear a comparison for the bracket method and any change in pop out or S3D for your setup!

Peace

[nubie]

Sorry, I haven't had mine setup in several months, busy with broken down cars and major home remodel (and a backhoe and Diesel truck for a friend).

Half the fun for me is playing around with all of the different settings, I don't really like pop-out personally, so I try to avoid it. I like it if it looks like a window into another world. My eyes nearly refuse to Diverge though, so maybe that explains my reticence.

Now that you mention it I want to try a "pop-out" demo in a dark room, maybe something like a spinning globe or rose.

What did you use for a mirror? I am thinking of buying a real glass beam-splitter (AKA half-silvered, two way mirrored, teleprompter mirror) from a local glass store, my acrylic is warped and the coating is water damaged (did I leave this in the rain or sneeze on it?)

I am glad you got it working , I need to build a proper mirror bracket for mine that can be adjusted with a simple screw, I have an idea that may only take a couple dollars, just need to get my car running and these rooms built.

[StereoGaming4Me]

Sorry, I haven't had mine setup in several months, busy with broken down cars and major home remodel (and a backhoe and Diesel truck for a friend).

Half the fun for me is playing around with all of the different settings, I don't really like pop-out personally, so I try to avoid it. I like it if it looks like a window into another world. My eyes nearly refuse to Diverge though, so maybe that explains my reticence.

Now that you mention it I want to try a "pop-out" demo in a dark room, maybe something like a spinning globe or rose.

What did you use for a mirror? I am thinking of buying a real glass beam-splitter (AKA half-silvered, two way mirrored, teleprompter mirror) from a local glass store, my acrylic is warped and the coating is water damaged (did I leave this in the rain or sneeze on it?)

I am glad you got it working , I need to build a proper mirror bracket for mine that can be adjusted with a simple screw, I have an idea that may only take a couple dollars, just need to get my car running and these rooms built.

I got a 70/30 teleprompter mirror from telepromptermirrors.com or something close to that for $152 or so. What showed up appeared to be a 50/50 piece instead after the "white card test" proved nothing, and they accept no returns at all, but the 50/50 works just fine. I'm very happy with the planar. If you order from them, as soon as the glass arrives call them and ask them to walk you through the white card test to see if they sent you a 50/50 instead of a 70/30 or 60/30. If you see no gap when a white index card is at the mirror, then that is the silvered side according to that company. On mine, there was no difference and both sides had the gap, but the reflected top lcd colors are slightly off in desktop mode.. would you say that is that normal? Also, I have to tilt the berezin $3 glasses slightly clockwise on my face to eliminate ghosting sometimes.

Thanks!

[distantreader]

Hi folks, there are lots of posts about this dual LCD + polarized glasses but all are about a vertical setup. I got a noob question that's been gnawing: why there is no talk about setting it up horizontally, similar to planar/mirror setup? Is it because it's technically not possible? This would eliminate the hassle building a framework for the vertical monitor. (You guys can see I haven't dwelled into this too much technically hence this silly question, BTW anyone has pointer to some good read on this dual LCD+polarized stuff better than what google gives?). Thks. DR

[Likay]

There's nothing that goes against a horisontal setup. Either you can have both monitors close to each other and view them crosseyed. (Crosseyed for long times = Eyestrain)
Another way is to have one mirror and mirror one monitor horisontally and have one eye looking straight at one monitor and the other looking at the other one through the mirror. Advantages with this is that you wont need any semireflective mirror. One simple mirror will do. The drawback with this kind of horisontal setup (and a quite big one) is that you need to have your head perfectly aligned to have a proper effect though.

It should work though!

[distantreader]

Yep I tried the "2 LCD + Mirror" method using just a handheld small mirror and saw that it works with a head movement restriction and that's why I'm interested in "the beamsplitter + 2 LCD + polarized glasses" technique since it solves the head movement restriction problem. But so far I've read only about vertical setup of this technique and none uses the horizontal method given that with the horizontal setup there is no need for an elaborate framework to hold the upper LCD, in addition both LCD's can still be used normally easily (just remove the beamsplitter and you can have a dual monitor setup for work, put it back in and you have nice S3D setup for games), I guess that's why I thought there might be technical issue that prevents such a setup and want to check first since to me it seems more practical and useful than the vertical method. DR

There's nothing that goes against a horisontal setup. Either you can have both monitors close to each other and view them crosseyed. (Crosseyed for long times = Eyestrain)
Another way is to have one mirror and mirror one monitor horisontally and have one eye looking straight at one monitor and the other looking at the other one through the mirror. Advantages with this is that you wont need any semireflective mirror. One simple mirror will do. The drawback with this kind of horisontal setup (and a quite big one) is that you need to have your head perfectly aligned to have a proper effect though.

It should work though!

[Likay]

And of course you should be able to use horisontal with a semireflective mirror as well. If the polarization of the lcd's is 45° or 135° it should work without extra retarders+polarizers.

[distantreader]

I'd hope polarized glasses vendors should have all kinds of flavors to sell and not just 45/135. I don't know what my LCD's polarization are except that they are different from my laptop's which also an unknown. It's likely that's the laptop being 45 degree and the desktop 0 degree, in that case I need to order a pair of 0/90 polarized glasses without resorting to retarders, I think.

And of course you should be able to use horisontal with a semireflective mirror as well. If the polarization of the lcd's is 45° or 135° it should work without extra retarders+polarizers.

[Likay]

The problem is that the semireflective mirror only handles the polarizationshift if the lcd's polarization is 45 or 135°. (Otherwise you need to shift polarization of one monitor 90° or both 45°).
But as said: It's nothing that some polarization foil (slight expensive) in combo with retarder (very cheap) cannot fix though.
Check polarization.com for both retarder as well as for polarizers.
Use qw-retarder for 45° shift and hw-retarder or double qw's for 90° shift.
This is only needed if your monitors have 0 or 90° polarization angle.

[distantreader]

The problem is that the semireflective mirror only handles the polarizationshift if the lcd's polarization is 45 or 135°. (Otherwise you need to shift polarization of one monitor 90° or both 45°).

This is good to know. I wasn't aware of this. Tks.

But as said: It's nothing that some polarization foil (slight expensive) in combo with retarder (very cheap) cannot fix though.
Check polarization.com for both retarder as well as for polarizers.
Use qw-retarder for 45° shift and hw-retarder or double qw's for 90° shift.
This is only needed if your monitors have 0 or 90° polarization angle.

Doesn't this cause additional loss of brightness? I hope it doesn't become as bad as what LCD shutterglasses has. Let's see, loss due to beamsplitter, loss due to additional retarder, loss due to polarized glasses. It can't be good. Before I spend time and money on this, I'd like to know more about this. Thanks Likay.

[Likay]

Yes, you'll loose a slight bit of light. However this can be used to compensate eventual light differences because of the semireflective mirror. Simply use ev. retarders/polarizers on the experienced brighter screen.

I once made a small vid how a retarder work. It's a quarterwave retarder and i use to it to shift 90° (should be two qw's or one single halfwave retarder for better performance) . You can check and estimate the light loss there.
http://www.mtbs3d.com/phpBB/viewtopic.p ... 8&start=14" onclick="window.open(this.href);return false;

[nubie]

Hi folks, there are lots of posts about this dual LCD + polarized glasses but all are about a vertical setup. I got a noob question that's been gnawing: why there is no talk about setting it up horizontally, similar to planar/mirror setup? Is it because it's technically not possible? This would eliminate the hassle building a framework for the vertical monitor. (You guys can see I haven't dwelled into this too much technically hence this silly question, BTW anyone has pointer to some good read on this dual LCD+polarized stuff better than what google gives?). Thks. DR

Good Question, since I haven't posted the pics in this thread yet, here is a link: http://picasaweb.google.com/nubie07/3DMonitor#" onclick="window.open(this.href);return false;

It works, but then where do your keyboard and mouse go? (Just kidding, I have used a slide-out keyboard tray before.)

This is how I used my setup until I got the mount built.

[distantreader]

Great! I've bookmarked it for future reference.
Could you pls compare the two setups with regard to ease of use, quality of 3D?
Thks much,
DR

Good Question, since I haven't posted the pics in this thread yet, here is a link: http://picasaweb.google.com/nubie07/3DMonitor#" onclick="window.open(this.href);return false;

It works, but then where do your keyboard and mouse go? (Just kidding, I have used a slide-out keyboard tray before.)

This is how I used my setup until I got the mount built.

[nubie]

Ease of use?

Mounted: Expensive, skill needed to construct, more room for keyboard and mouse, better view angle if you like to look down at the screen. May bump head on top screen leaning forward though.

On a desk: OK as long as you can get the mirror lined up. Best with a platform 8-12 inches above desk height so you have room on the desktop, and so you are looking into the screen. Needs nothing but 2 LCDs and a piece of glass, so near free. Nothing to build, just set on a desk. Option to slide second screen back and use 2 monitors (great if you do any 3D modeling/texturing, or work with Gimp/Photoshop)

I dunno, I think I wanted to build the mounted version because it makes the most sense, you look in a horizontal fashion and getting the second monitor out of the way helps.

[anotherFrench]

hi all, I'm trying to apply this method in a lcd projection system, so I searched a mirror that could do the trick.
I found 1 called "antelio" at a local shop so I guess you can find it anywhere, it seem to work great for desktop use, I tryed it with 2 17" crt's and the results look very good to me:
http://forum.allinbox.com/aspectgeek/Pr ... 9151_2.htm" onclick="window.open(this.href);return false;
I didn't try it with polarised filters, don't want to buy them because the 2 crt's setup was just a test and is too "big" to keep on my desk so I think it's better to use 2 lcd's wich are polarized already but the rendering of the 2 pictures seem to be very good
sorry it's a french forum but you can see the pics anyway.