Triple Screen Fresnel Lens Display for $220

[Turn]

7 Foot Wide Triple Screen Fresnel Lens Display for $220.

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I just finished a prototype which turned out so well I thought I'd share some details.

It uses 3x19 inch monitors magnified by Fresnel lenses to give a near-seamless 135° FOV. The lenses fool the eye into believing the image is approximately 7 feet wide and farther away than it actually is; more like what eyes are used to focusing on in real life.

It can be built for a little over $200 including the cost of cheap second hand 19" LCD monitors (plentiful in most areas). Here's a link to the lens I used: http://bhlens.com/product_detail.aspx?pid=34

The overall weight is only a few pounds (plus monitors); easily made lighter by detaching the monitor stands and hard-mounting, and the compactness delivers the small moment of inertia important for motion simulators.

Please note: I am in no way promoting the use of the wooden table structure for a motion platform That's just something I whipped together in a couple hours for proof of concept of what's above it.

Now, I never normally get sick playing video games. However, the overall effect of this design is so immersive that I got quite motion sick and nauseous for the first few hours of trying iRacing with it. I think that means it's working My explanation of this is that the eyes and brain get completely convinced you really are in that virtual space, but there are no motion cues to go with it as you zip around the track (i.e. inner ear sensations), which it normally expects to receive. Thankfully, you get get used to it with time (at least I did), and are left with what I think is an amazing experience. The videos below don't do this justice.

Technical Details:

The side lenses/monitors are angled 45° inward and each monitor is about 19cm behind its respective lens. This gives a roughly 1.7x magnification equivalent to a 31" monitor. My viewing position is roughly at the perpendicular intersection of all three lens centers. Overall resolution is 3840x1024. Each monitor is 1280x1024 and is a 5:4 ratio,19" diagonal in size. I would not recommend using anything over 20", nor any of the widescreen 16:9 monitor types as they are not suitable for the lenses which are 40x32cm. The 5:4 x3 ratio is perfect as you also get a nice vertical FOV too. Overall, the 19" size is perfect for this application. I recommend trying to find three with very similar image & color qualities, if possible.

I'm sure this concept is nothing new to motion rig builders, but I sure don't see many people doing it. Not sure why.... highly recommended!

One lap in iRacing:
http://youtu.be/kOMREPZNYwM

Walkthrough videos:
http://youtu.be/KjVFaZc9pw8
http://youtu.be/FpFnY_3QVcU

Pics:

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[ferslash]

nice project!

some questions:

* What kind of hardware are you using to split the signal for the 3 monitors
* does the day light affects the experience ?
* when you move your head and the distance from the fresnels changes, you get bloor images or it is just the same no matter if you move or not

by the way i really liked


fer

[Turn]

Hey fer. Great questions.

-It is by design where spending less here actually gets you more. Because it runs at "only" 3840x1024 a super high-end cards is not required, so I'm using a $150 HD Radeon 6870 (all settings maxed in iRacing yields >85fps always).

-I expected to need to enclose the lenses and monitors inside shades right away, but I haven't bothered yet because daylight does not affect the experience as much as I had read from others that it would. And I'm in a terrible location 12" below a large window. I was really surprised that even with the blinds wide open it's fine. I'd never play that way intentionally because, yes, there are some refractive effects, but they're minimal. My final design would see it enclosed just because I'm a perfectionist, but it should tell you something that I've played with it for a week as is with few complaints.

-As far as lens bloom goes, and other undesirable artifacts, one thing I've learned is they are insignificant if you're sitting at or near the natural focal point of the lens. That's key. If you do this, you can move your head around a lot and there's no problem. If you try to increase the magnification factor by sitting farther away from the lens, yes, the image gets bigger, but you're asking for trouble in all other areas because distortions of all kind increase. My lens focal length is 50cm and I sit about 54cm away. I can press my nose right to the lens and bobble my head around lots (more than you ever normally would) with no problems..

[motiondave]

Nice idea there, well done!

[floriske]

This is a very promising/impressive experiment! I have not seen Fresnel lenses in use before but looking at the video I think it looks amazing.

Compliments on the work and somehow I get the feeling that due to your work we will see more setups like this.

[ferslash]

totaly agree with florink, now i will be obsessed about your set up ajajjaja

[yokoyoko]

Hi Turn,

I don't know how to thank you in a reasonable way!!! This is one of the greatest mods of my rig so far.
I copied your setup - ordered 3 dirt cheap 19inch monitors on ebay - and the mentioned lenses in china. They sent them very quick to Germany! Just the shipping price is ... But I found no alternative in europe (the prices in China are really crazy cheap!)

The whole setup is und 200€ with cables, aluminium to mount, lenses and monitors... and what you get for this is really great!

I was sceptical if a seatmover is good for such a kind of setup because the Sim moves you around the "focus" of the lenses AND the lenses need to be mounted very stable if you got motion But after testing all doubts are away - this rocks so hard!

Here a pic:

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Don't get confused by the pic - if you sit on the seat everything (images) fits perfectly. --> This is the hardest part of the job

I know - this looks veeeery prototype like. A friend is doing a frame for me that will fit exactly for the lenses and locks up with the monitors. This will be overdrawn with black suede - so it will look like ONE big screen.

Thanks and reagrds
yoko

[ferslash]

woow that pics are grate!, impressive... please post some videos if you have some time


fer

[yokoyoko]

Hi and thanks ferslash.

I will send videos soon as possible. At the moment i'm writing on a tut how to build this thing at home... But mainly in my earlier setup.

@ turn: how have you made the video while driving (the iracing spec racer one)? I dont get this work.... Driving while holding the camera is impossible. Have you sticked your cam to an helmet or cap? With motion running i will need some downhill mountainbiker videoequipment, i guess

[tronicgr]

Maybe a gopro hero wide