Meant to be Seen

Well stuff it i say, im sick of waiting so begins my possible insane hmd build up. I have just ordered on fleabay a 7inch lcd native res of 800x600 that can 1024x768 for $85au. If its decent and seems like a go i will buy another and bolt them to a helmet with fresnal lenses, headphones and an air mouse.

I may end up mounting them sideways and using mirrors or just angled and use prisms (maybe even cd case prisms

With if it works out i will have a dual input 3d hmd with mouse head tracking and massice FOV for about $250.

If it frazels i may just use the first screen and air mouse to make a game gun

Update-----

Ok my screen arrived and ive had a fiddle. Unfortunatly it is 16.9. It is actaully a liitle tv and does 4.3 mode on tv or AV input but not VGA input 4.3 . Also seems it is native 640x480 so the windows desktop looks like ass in anything over that but games look ok up to 1024x768. I squashed the horizontal adjust a bit to fix the aspect and it will be good enough for now. One good part is you can crank up the res over 1200 and it will still display it just gets tare lines through it.


Had a play using my credit card fresnals and it seems that these will do close to the eye with the screen at about 6 inches. I had a try holding the screen beside my head and looking into a compact mirror- this would be ideal if i could source a cheap front surface mirror and work out a way to flip the image.

Also of note. Using a fresnal through a single eye does not give the huge image effect, its only once you pull back your head and look through with both eyes, will be interesting to see how one for each screen goes, it may come down to how i separate the eye convergance with the lenses.

Ive tried to use the iz3d side by side mode but cant get the driver working on any of my lappys with 9100 igp's so i will try that later. I did look at a stereo pair using 2 credit card fresnals and that works perfectly, the fresnels give you a few inches offset so no need at all for prisms or such at such small separation.

Ive decided to order the second screen. Still waiting for my hemlet. Once the screen arrives i can work out positioning and fixed optics and begin mounting.

I was going to get a dualhead2go so i could run both screens from a single lappy (maybe make it mountable later) but it seems they dont support dual monitors, only wide screen so the only driver that could work would be iz3d side by side and i dont have enough faith in that at the moment.

Does anyone know if the xp nvidia stereo can work with a dh2go in dual screen mode?

Mini Update-
Helmet has arrived, should be workable with added foam to tighten it around the head and remove wobble.
I have ordered 2 different types of fresnals form 3dlens that should arrive soon that should do a better job than the cheaper credit card fresnels. I also tried some big magnifying glasses- not enough magnification which is a shame as they would be sturdier and clearer. Im going for the biggest FOV i can.
Second screen still hasn't arrived so i cant get into the meat and potatoes just yet

Oh and ive done silly things and ordered 2x Gigaware pico projectors . I think these are rebadged Oculons http://www.oculon.com.tw/en/index.aspx" onclick="window.open(this.href);return false; (some cool thing coming from them by the looks). Oh i also bought a $10 sphere paper lamp shade from Ikea about 70cm diametre.

Whos knows what i will make out of all this junk

Update: Ok the 3dlense fresnels arrived and they are of a suitable size to get a large fov with the screens mounted close.
The second screen has arrived so i begin testing.... here i hit the wall. I knew it was coming but was living on wishfull thinking. I need to seperate the convergance in a BIG way. My glass prisms are no where near enough offset, the fresnels are no better. I am going to have to make this with mirrors somehow or try making some very large angle prisms.
Either way is less than optimum because of size, weight and deformation.
Giving this some thought....

Update:
My first Gigaware (Oculon 920) projector arrived today. In the pic i have it shining on some paper with a focussed screen of about 3 inchs, this can be done easily but sometime the focus ring around the lens comes off if you screw it in too far so i had to take it apart to have have a look... i mean fix it
The projector is a nice little gadget, up to xga with readable quality, just very dull and requires absolute darkenss for any size and usefullness. Also has a VERY LOUD fan to cool the LED.

I believe 2 of these (or better still 2 3m pico's because they are narrow) can be used on top of a helmet, bounced back from a mirror if front to a rear projection screen in front of the eyes with a decent result.
Well after deciding its too tuff for now to use 2x7 inch screens ive made up a high FOV mono HMD.

Its an airsoft helmet with some meccano (this stuff is awesome for projects) holding this together. A gyration air mouse on top and some batteries on the back for ballast. It started with a single fresnel but then i added another (check last photo). The FOV is huge but not 180 of course but pretty much fills the majority of the view except that the top and bottom is visible. Its quite blurry as you would expect but you can read text still. It really comes to life when you stand up with a second air mouse in the hand and start turning around. I didnt have any earphones hooked up as ive ordered a 5m cable. I will extend the video and power cables as well. I will also get some black card and cloth to make a cowl and wall off the insides as it is much better in the dark and fresnels dont like light reflecting on them.


Next up, i have another 2x3.5 inch low res screens coming and some more bits so ill make a stereoscopic one that will rely on an external monitor to read the text but its a trial to see if i want to splurge on the expensive vga screens.

On a side not i also pulled apart my Eyeclops night vision goggles. I wanted to see i could do anything with the optics (and maybe move on to a vr920) but its a no go. The screens in these things are tiny, about 10mm wideand you would need a whole bunch of specific lenses to do any justice. You can see it glowing just to the right of my thumb in the last pic how tiny it is with the optics removed. Want i still want to do with thses things though is rip out the board cam and eyepiece and set them up as a true monocular intead of the camera being on the forehead which really put you out of sorts.

2x7" within a hmd? That's surely insane but an interesting project indeed. Are you sure about the fresnels? Maybe there are suitable lenses that will give a proper view when those giant screens are close to your eyes? The fov would really kick!

I wish you the best of luck. I, too, am about ready to try to build an HMD since it doesn't seem like any company wants to make something decent. Please let me know how it goes, maybe it will help me once I get the money to build one.

Likay wrote:2x7" within a hmd? That's surely insane but an interesting project indeed. Are you sure about the fresnels? Maybe there are suitable lenses that will give a proper view when those giant screens are close to your eyes? The fov would really kick!

This is going to be the trick, getting enough eye relief so the screens are not too close. I have zero hopes of finding any type of lenses other than fresnals even partialy suitable. I will play around with credit card size ones to start. Im guessing im going to have to mount teh screen on a boom to do this so balance and weight will be a factor, i may have to counter balance and it could get unworklable quickly.

My other consideration is to use a single screen with fresnal for large field of view immersion with stereo.

Was going to use mini projectors but all thing considered they can only make it more difficult and expensive.

cybereality wrote:I wish you the best of luck. I, too, am about ready to try to build an HMD since it doesn't seem like any company wants to make something decent. Please let me know how it goes, maybe it will help me once I get the money to build one.

What are your thoughts on how to go about it? If i thought it was possible to add good lenses to an VR920 to get a big FOV i would do this for sure, but i cant see it happening. Plus this way will cost almost half price and be higher res

I was seriously considering getting pico projectors but they are $200au each. Messing around with mirrors and they have a minimal focus distance plus i would end up with a smaller screen to try and magnify.

The 7 inch screens seem like the blunt force trauma method but the simplest...

Personally I want to try the pico projector route. The ShowWX projector looks perfect for this. I would mount them on the side of the head and have and mirror about 6 inches from the face. Then in the middle would be a screen and in front of that a fresnel lens. I would be planning on having around 6"-8" screen area per eye, so if you are getting a 7" LCD screen that should work just as well. Still not sure if I'm going to try this though. The pico projectors alone would cost $1,000 plus all the other parts. Not cheap. Still, I can dream...

Hey how do these lcd screen get connected to a pc anyways? Do you have to use an adapter of some sort? Like the game gun, could he of used a laptop screen as well to get a bigger screen?

Ku

VRgamesterz wrote:Hey how do these lcd screen get connected to a pc anyways? Do you have to use an adapter of some sort? Like the game gun, could he of used a laptop screen as well to get a bigger screen?

Ku

The one ive ordered is an actual monitor(and tv) with vga in though a supplied adaptor cable. You cant go using laptop lcd's because you need the driver board for them.

For me it seems as if a single screen + fresnel (+ anaglyph glasses like the pro-ana) solution could be a very cost effective and very immersive experience? Maybe i´m going to try a solution like that in the forthcoming months as well.

SinSilla wrote:For me it seems as if a single screen + fresnel (+ anaglyph glasses like the pro-ana) solution could be a very cost effective and very immersive experience? Maybe i´m going to try a solution like that in the forthcoming months as well.

Yeah i think this will work well but for myself i cant handle anaglyph it annoys me having terrible color too much.

Another single screen option i will try with be the iz3d side by side driver, the resolution will be absolutley terrible once cropped out form an 800x600 display but ill have a look anyway.

Dual 7" LCDs are going to be hell to view with your eyes and any kind of standard optics, the center is too far off IPD. The only way you will be able to do it is to get some lenses that offset the viewing angle to be a few inches at a good focal length.

Luckily, I have some lenses that do just that! I was planning on someday doing what you are discussing, but I have other ways to accomplish my wants, so you will get a lot more out of these than me. PM me your address and I will send em off to you, as long as you promise to do something with them.


EDIT: Awww, damnit. These lenses were made with smaller screens in mind, I assumed they work, and they do, but they end up cutting off the sides of the screen on a 7". You might want to try and adapt the oil filled glasses idea, it should do a good job, if a bit more bulky.

PalmerTech wrote:Dual 7" LCDs are going to be hell to view with your eyes and any kind of standard optics, the center is too far off IPD. The only way you will be able to do it is to get some lenses that offset the viewing angle to be a few inches at a good focal length.

Luckily, I have some lenses that do just that! I was planning on someday doing what you are discussing, but I have other ways to accomplish my wants, so you will get a lot more out of these than me. PM me your address and I will send em off to you, as long as you promise to do something with them.


EDIT: Awww, damnit. These lenses were made with smaller screens in mind, I assumed they work, and they do, but they end up cutting off the sides of the screen on a 7". You might want to try and adapt the oil filled glasses idea, it should do a good job, if a bit more bulky.

Thanks for the offer Palmer. I realised i would need some type of offset optics and was going to start experimenting once the screen arrived so i work out what i will need to get the full screen view.

By the way - some OLD stereoscopic HMD's (early-90's era) used big LCD's, but manufacturer's locate actual LCD'd on the side's of helmet, and show the picture for the user's eye through mirror-system. In this way you can use pretty big LCD's.

A few more point's from my side - actually I think this is possible to view dual-image on one LCD infront of the eyes, and make stereo via custom-made prism.
Also, it is possible to go with custom auto-stereoscopic solution with parallax-barriers, you have ideal condition for this - head position is fixed, distance to the screen always the same etc.

Johnny-Mnemonic wrote:By the way - some OLD stereoscopic HMD's (early-90's era) used big LCD's, but manufacturer's locate actual LCD'd on the side's of helmet, and show the picture for the user's eye through mirror-system. In this way you can use pretty big LCD's.

I tried this and would work great. The screens would be closer the the helment to help balance but i would need to find good front surface mirrors, then i need to find a way to reverse the image.

Johnny-Mnemonic wrote:A few more point's from my side - actually I think this is possible to view dual-image on one LCD infront of the eyes, and make stereo via custom-made prism.
Also, it is possible to go with custom auto-stereoscopic solution with parallax-barriers, you have ideal condition for this - head position is fixed, distance to the screen always the same etc.

This would be cool. It would be made more difficult but the difference resoltions ill will be running and teh optice i use so ill leave this for Cyber

OP update.

Can't you flip the screen in software?

Hi Okta, good to see you made some progress!

How is the Image quality with the fresnel (whats the groove pitch on yours?) close to your eyes? Do you notice the grooves?

I´m pretty curious how your lens setup will look like in the end, i could imagine that it will be pretty hard to focus the center of the screens/mirrors with a width of roughly 6".

And you were right, anaglyph shouldn´t be the way to go when building something new, therefore I did some testing with a simulated 3,5" screen (actually my 4" cellphone display) and a rectangular 8 diopters planconvex glass optic which worked pretty good at ~4" distance. But i still need some more magnification to get the Fov i was aiming for.

I hope to see more updates and maybe some pictures of your progress soon, very inspiring!

Greetings, Sin

Sounds cool. I wish you the best of luck.

Check these out - http://shop.ebay.com.au/vitrolight/m.ht ... ksid=p4340" onclick="window.open(this.href);return false;

If i didnt have my screen(s) already i would have gone this route. Although it would be much harder to get a big FOV with smaller screens.

Mini update.

Hi Okta,

have a look at this page if you want.

Lupenshop.de

Instead of using fresnels you could go for bi-aspheric plastic lenses since they´re available with large diameters, shorter focal length, bigger magnification and they should give a better picture quality (no grooves).

A shame its not in english, still it would be difficult to pick a good match without trial and error and rather pricey im thinking but for using micro displays these optics would be good.

Yeah unfortunately it is in german.

Just wanted to hint at another approach with it.

Yes, trial and error seems almost unavoidable, at least for me since i´m missing the knowledge to calculate all that stuff. ^^ But as long as it´s fun i have no problem with that.

Have received my VFX1 yesterday, i´m now waiting for different fresnels and other lenses to arrive to continue the experiments.

Good luck to you, keep us updated!

What kind of helmet will you use btw?

This one here, great price and looks cool http://cgi.ebay.com.au/ws/eBayISAPI.dll ... K:MEWNX:IT" onclick="window.open(this.href);return false;

ill post up some pics once i get less lazy.

Looking forward to it!

Oh wow, this project is sounding better and better. I think I am going to have to start trying to build one too. LOL!

Update- the the wall...

Can you explain what you mean by "separate the convergence"?. I take it the screens are too far apart or something?

Yeah thats it exactly, as Palmer pointed out before they are too off from IPD. I need to offset this with prisms or mirrors in a big way. The simplest methos of a single mirror each is noit feasable becuase i cant find a way to reverse the image in software or hardware. I will try building a prism when i get time but is will need to be huge, at least 45 degrees and heavy

You said before your screens are taking 640x480... Have you tried outputting 800x480 to them? Likely that is the native res.

I also bought one of those Gigaware projectors, they are interesting, but not useful for HMDs too much. They use the same 0.44" display as the VR920, actually. Might be useful for actual projection, though.

Any shot at a double mirror?

Given the FOV im after and the screen size double mirrors will be very difficult i think. I need a few more mirrors to play around with. AT least i know how to make front surface now if i find something usefull.

How did you find the gigaware projector? I didnt hold much hope of use for a hmd, any chance of a mini passive setup with 2 or just not enough lumens? Have you had a look inside to consider brighter leds?

Ive also ordered a cheap vga-tv converter box and a 3.5 inch reversing lcd to play with

Okta wrote:Given the FOV im after and the screen size double mirrors will be very difficult i think. I need a few more mirrors to play around with. AT least i know how to make front surface now if i find something usefull.

How did you find the gigaware projector? I didnt hold much hope of use for a hmd, any chance of a mini passive setup with 2 or just not enough lumens? Have you had a look inside to consider brighter leds?

Ive also ordered a cheap vga-tv converter box and a 3.5 inch reversing lcd to play with

Radioshack sells the Gigaware projector for $99. I saw one, saw it had VGA and was 640x480, so I pulled the trigger. I actually bought it to use for HMD experimentation, truth be told... Mini passive setup would be very interesting. The problem is, the lumen output is already really low. Yes, there are brighter LEDs out there, but they need fan cooling and eat a lot more power, and the gain is really not very high (The LED in it is actually already far more powerful than most consumer garbage). Right now, I am trying to figure out how possible it would be to make a rear projection setup, one projector for each eye. The guts of the projector are very, very light, so it could be mounted as far as a foot or so in front of the eye and still not be a huge issue. Basically, I would want a small dome of rear projection material for each eye, and have each projector mounted in front of it. Rear projection helps hide screen door effect from low resolution, so might actually work decently.


You have no idea how many LCDs and bits of optical display I have picked up over the past years, especially these past few months. I work on portable game system conversions, but this HMD hobby has me working hard. I am just terrible at documenting it.

What really excites me is those new laser based PicoProjectors. Boy oh boy do I want to get one... I have some serious plans laid out.

PalmerTech wrote: What really excites me is those new laser based PicoProjectors. Boy oh boy do I want to get one... I have some serious plans laid out.

I know, I'm so close to pulling the trigger on the Show WX (which just came out). I'm sure it could be useful somehow.

Okta wrote:Yeah thats it exactly, as Palmer pointed out before they are too off from IPD. I need to offset this with prisms or mirrors in a big way. The simplest methos of a single mirror each is noit feasable becuase i cant find a way to reverse the image in software or hardware. I will try building a prism when i get time but is will need to be huge, at least 45 degrees and heavy

You could use penta prisms. They reflect at 90 degrees and don't flip the image. However, those things might be too heavy and too expensive. You might want to look at internet surplus stores for used optics to pay less. I'm not sure it would work in an hmd because you could look toward the wrong surfaces of the prism.

Another solution would be to use two regular mirrors. You could have the screens on each side of your head pointing forward, one mirror would reflect the light 90 degrees toward your nose and the other mirror would reflect toward the eyes. Reflecting two times will flip the pic twice so it will not get flipped. You can use 90 degrees prisms instead of mirrors to get better picture quality. It might not work if the light path is too long for your optics.

Some pics added.

I don't really get how this works. You would have to mount those huge displays on a helmet and scale the image with some lenses to be far away, but seem large to the eyes to focus them.
I don't understand how such an optic works. Can someone explain this "prism"- solution
I would love to build such a HMD on my own. I have a budget of ~ 1000Euro.
I want a resolution like 1280x720 and >40° FOV.
I search desperately to find small, but high res displays. Getting something like 640x480 or 800x600 does not really make sense as i could get a vr920 or z800.

If anyone could post working hardware, i would build it.

My current problem with this build is not the focus but that the screens together are too wide overal. This means my eyes need to point outwards for it to work. I have yet to do more work either with prisms or mirrors. I am also waiting on a 3.5 inch lcd for testing.

Check these displays here- http://stores.shop.ebay.com.au/VitroLig ... QQ_armrsZ1" onclick="window.open(this.href);return false;

You could go for the vr920 or z800 but you would be better of with a 3d 22inch monitor as the view will be bigger.

Defender wrote:I don't really get how this works. You would have to mount those huge displays on a helmet and scale the image with some lenses to be far away, but seem large to the eyes to focus them.
I don't understand how such an optic works. Can someone explain this "prism"- solution
I would love to build such a HMD on my own. I have a budget of ~ 1000Euro.
I want a resolution like 1280x720 and >40° FOV.
I search desperately to find small, but high res displays. Getting something like 640x480 or 800x600 does not really make sense as i could get a vr920 or z800.

If anyone could post working hardware, i would build it.

Does it need to be 3D capable? Okta has a great project here, but I have a 1280x800 HMD with 85 degree FOV that I made using a heavily modified MRG2.2. It is not done, but I can finish it up pretty fast, it is already in the "working fine" stage. Would you be interested in it? If so, PM me.


I wish you luck Okta, update us when you can!

I have a 22 inch iz3d monitor at the moment.

Of course the HMD should be 3D. This is the most important point. Hey we are at MTBS3D here! I don't think the MRG can be modified to stereoscopic.

I had a z800 and sold it because it hat so bad game support. Now 2 years later it doubled in price and we have iz3d drivers now.
I thinking about rebuying one but it has so low resolution and the support in iz3d driver does not seem to work perfect as i read.

The link you posted for the ebay displays has only low resolution displays. The best resolution/size choice would be the 4.8inch 1024x600 display, which is still rather large.

Can someone post optics which would fit such a display? I don't have any idea how to place a display so close to the eyes and make it focusable by the eyes. Is there some technical document available here at the forums to understand how HMD optics work.

I have a few magnifying glasses at home and made a simple try with those. Besides magnifying they also makes it possible to view things at a closer distance but at a cost of distortions in the periphery. The lenses needs to be kept closer to your eyes than the display to work properly.
If i use more than one the viewing distance decreases but i also get more distortion. I don't know if you can circumvent this by using different lenses.
So i guess you should only need a pair of convex magnifying lenses but you'll also get peripheral distortion. Do anyone know if you have this using standard hmd's?
I can't say i know too much about optics on higher levels than this so leave this open for other suggestions!