PR2, a DIY, low cost, high FOV stereoscopic HMD

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PalmerTech
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PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by PalmerTech »

Hey guys! I have been working on this for a while, and there are even more improvements in the pipeline. This design was developed on my own time, with my own funds, helped me get my current job. And boy, does it blow away anything on the consumer market. ;) I consider it a successor to the PR1 (Prototype 1): http://www.mtbs3d.com/phpbb/viewtopic.php?f=120&t=11970" onclick="window.open(this.href);return false;

First, some pictures:

Image

Image

Image

Specs:

~120 degree diagonal FOV
100% binocular overlap
Optics are essentially modified LEEP clones
SVGA resolution per eye
Diffusion filter
VGA/USB input
3 DOF motion tracker
No headmount, you get to hold it
Takes side by side input

The PR2 is actually the culmination of several cobbled together prototypes, and is the first I am comfortable actually giving a name to. It has a very, very fine grain diffusion filter that does not reduce the detail of the image, but blurs just enough that the RGB elements are completely invisible. The displays I am using have a very high fill ratio, so the lines between pixels are not visible, either. :D

Total cost: Less than $500 in parts, if you ignore the many hours of labor, and countless failed prototypes. :lol:

Questions? Ask them, I love those. :mrgreen:
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Okta
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by Okta »

Here we go :)

1.What displays/drivers have you used?
2.How did you get side by side working with one vga input? Unless its a single screen divided in 2?
3.How comfortable is the image?
4.What is the perceived distance/size of the screens?
5. How do i make one? :)

edit-
6.Can the driver interpolate a higher resolution?

edit again-
7.Will you show us the project work up and internal photos?
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by cybereality »

That looks like an interesting project. Will it have a head-mount at some point? Seems like a nice fit for a Virtual Boy style bi-pod, though that would negate the tracking.

Is the tracker you are using any good? Does it have a driver or mouse emulator? Could it be used with the HMZ-T1?
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by PalmerTech »

@Okta:

1) A single 1280x800 panel, same as the PR2
2) Yup, I just split a single panel in two
3) I spend a lot of time making the image comfortable, focus is set at 12 feet, massive exit pupil
4) I need to calculate that (Have someone making a program that projects a grid that lets me test), but for a rough idea of the size, imagine a 24" monitor from about a foot away. Like I said, though, focus is set at 12', as close as I could get to infinity. The difference between 12' and infinity is minuscule, in terms of focus.
5) You can make one with a screen, a control board, a few lenses, and vac-forming plastic/tape/glue. :D
6) It can interpolate higher resolutions, but it does not really make a difference. I think it might actually be worse, since the scaler is not all that great.
7) I actually took no build log photos. :P I had no idea this was going to be the "final" version until very late in the build process.

I could make a tutorial on this, but at this point, I do not think I should. Why? Because the next version is so, so much better! ;) Beyond that, I am thinking maybe I could do a bulk buy of all the parts, and sell them as a kit. If I did that, I would make a project on Kickstarter to see if enough people were interested.

@Cyber: This particular unit will not, I think it is going to live its life as a handheld viewer that you can pass around. A bit in the style of the old LEEP viewers, really. However, the next version is nearly done, and it will have a headmount. The tracker I am using is garbage. :lol: It was a last minute add on so I could roughly test looking around in-game. The immersion of this display is fantastic, it is hard to believe the impact of high FOV until you see it with your own eyes. Once I get all the kinks worked out, would love to send you one of these units to test out! If anybody else would be interested in trying it, let me know.

The next revision has a lot of improvements, and is actually in working form right now. If anybody wants me to make a thread for it now, I will.

Improvements for the PR3:
Much lighter (~700 grams, only 200 grams heavier than the Emagin Z800)
About 20% smaller, mostly depth wise
Wireless video receiver fanny pack/backpack/belt pack, not decided on final form factor
Lightweight lithium polymer battery pack, runs wirelessly for about 10 hours on a charge
Swappable lens faceplate, lets you move from 120 FOV to 60 FOV in less than a minute, or upgrade to future lens designs

One more thing to mention: The contrast ratio/color reproduction in these units is stellar, far superior to any microdisplays that are used in HMDs on the market.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by 3dvison »

I want to know how you made the optics ?
Looks so cool.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by Syntax »

wow, awesome job PalmerTech, this is major leap forward in terms of highend consumer hmds.
And only 500 bucks for 120 degree FOV this is badass :twisted:
I mean I tested the HMZ from Sony(52 degree) and it blew me away ^^

Now you said that you are using a single 1280x800 panel.
Are these the best panels (highest resolution for that size) you can find of or are there panels with more pixels out there (1080p or more) that would fit the device-shape and what price diverantage is there.
Also the company Sensics were using multiple lcd panels to create an ultra FOV HMD maybe this is were future hmds are heading.

I also was wondering about how much resolution is need to create a perfect natural lifelike vision... 4k,8k,16k ??? :roll:
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by foisi »

Wow this is impressive, very nice job PalmerTech :)
I have questions too if you don't mind :
1) what is the panel you used ? is it Vitrolight 5.6" 1280x800 TFT LCD module ?
1.5) if yes how did you fit the controller board into your device and has it hdmi input (1.3 of course) ?
2) in your new prototype, did you use the same panel ?
3) did you try aspheric lenses like I use in my project ?

Thank you for sharing this :)

@syntax :
from wikipedia, angular resolution of the human eye is 0.017° so with a 150° FOV you will need
150 / 0.017 = 8823.529411764704 horizontal pixels per eye
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by nrp »

I'm also interested in the optics design. Did you get lenses custom ground/molded, or did you assemble a LEEP setup from off the shelf lenses? Any plans to publish schematics of the optics design?
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by PalmerTech »

@3Dvision: See answer further down. :)

@Syntax: Keep in mind that this thing has about four times the apparent screen size of the HMZ. Really, really immersive, wish Sony would do it themselves! :lol: There are higher resolution panels I could use in existence. However, the price difference is absolutely enormous. :( Adapting 1080p panel would be bulkier, lower FOV (Because of the size of the panel), and most importantly, cost several thousand dollars! As prices drop, this will be less and less of a concern, but it will be years before that happens. Sensics stuff is interesting, but does not provide the seamless VR imagery I am shooting for. And then there is the fact that most Sensics products are in the $50,000+ range!

@Foisi:

1) Yup, that is the panel!
1.5) This prototype only has VGA, it was good for a test since the board was so small. Have you seen the 7 in 1 control board, the one with HDMI input? You can actually cut it down a lot if you short out a few pads that make it ignore the missing analog section of the board. Here is a picture of the 7 in 1 board vs a cut down version (Still works perfectly): Image
I cut it down enough where I COULD fit it into the HMD... But I actually have a different plan. The control board will go in the wireless receiver/battery pack, and I have made a custom LVDS extension cable. This helps cut down on weight dramatically!
2) Yes, I am using the same panel in my next prototype.
3) I have indeed tried using aspheric lenses, but I found they tend to strain the eyes more than LEEP clones, at least when you need magnification as high as I am using. Probably not as much an issue for your 7" panel, as it is much larger. At my new job, I can spend as much money as I want on fancy lenses, so I will be revisiting aspheres again :)


@nrp: I actually got my hands on three sets of LEEP optics, and set about making clones of them. I was able to make them out of off the shelf parts, more or less. Real LEEPs have a third element that provides a bit of magnification and adjusts the distortion, but that also makes them a lot heavier. Currently, my LEEP clones are filled completely by my panel, with the far right and left edges barely visible. With 120 FOV, though, you don't even notice the edges! Only a few pixels on the far corners are cut off, a compromise I am willing to make. Since the next prototype has swappable lens faceplates, you could easily switch to a lower FOV lens set that shows all of the display and has a higher angular resolution.

I would publish schematics of the optical design, but this entire design is really just a rough draft. I would rather not have people copying my rushed, flawed design. :lol: Makes sense, right? Once I finalize the optics, I will put together a guide on how to build them.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by Okta »

Being side by side will really drop down the res obviously as i suppose most of the top and bottom with be unused when letter boxing the content to correct the aspect ratio. Does your divided display have good view centering or would you recommend a slightly larger or smaller screen?
I am going to start playing with side by side videos on my 7 inch Android tablet now :D

Please make a thread for the next model.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by brantlew »

Hi guys - recent follower of this forum and first time poster.

PalmerTech, awesome work! Please post the guide when you get things working. It sounds like a really fun project. I've been waiting on the Wrap 1200VR reviews to come in for possible use with remote stereoscopic cameras and a telepresence project that I have been working on. The Vuzix sounds a bit disappointing quality-wise but for various other reasons I will probably still go with one of the Vuzix products, but I would like to do some research with your assembly as well.

It seems that most people on these forums are focused on gaming and virtual reality, but another arena where this technology has big potential is in telepresence. Imagine attending a meeting with a robotic camera system stand-in on one side and a quality head-tracking HMD system on the other.

I look forward to your guide...
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by PalmerTech »

@Okta: You are correct, using a correct aspect ratio limits me to 640x480 per eye, and you lose some vertical FOV. Using it at my new job, though, we just tell our engine to output at the correct aspect ratio/resolution. In theory, the IZ3D drivers could handle this, but they never got around to doing it before stopping updates. :( As for view centering, this panel is nearly ideal. Human IPD is 60mm to 75mm, and the active area of this panel is 121mm wide; 60.5mm for each eye! Unless the user is in the 5% or so of the population with a 60mm IPD, it works perfectly, and you could theoretically adjust in software. There could not be a better size! I will make a thread for the PR3 sometime tomorrow, hopefully.

@Brantlew: Great to see a new addition to our ranks of HMD enthusiasts! :) It would be cool if you made a thread for your telepresence project, a lot of us would have useful advice and input (I know I would!). I actually have some experience with telepresence using HMDs, I have built setups that were for an underwater ROV. As for Vuzix... have you ever used any of their products?
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by 3dvison »

I can not wait (but will..) to see how to build those optics....
Even with all the talk of the new Sony HMZ, the pull to build a DIY HMD with a large FOV is strong.
I think your optics would give the push needed for me and others on these forums to start building our own DIY HMD . I think the optics are a stumbling block that stops DIY HMD's in their tracks.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by brantlew »

PalmerTech - No I have never owned or even tried an HMD of any kind. The main reason I am focusing on Vuzix is because video teleconferencing is a 2-way deal and wearing a helmet or gigantic box on my head would be both embarrassing and distracting for the person on the other side. The Vuzix (while having some quality faults) at least attempts to provide a presentable form factor.

I would welcome any help on these matters. I am a skilled programmer and well versed in 3D graphics but a lot of these optical concepts are very new to me. If you are interested in my telepresence project I have a detailed blog about it here:
http://teledev.blogspot.com/2011/07/diy ... art-1.html.

It works just fine now, but at some point I would like to add HMD support to it.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by cybereality »

That robot looks really cool, but I am not sure adding HMD support will make it any better. Well, if it were a one-way deal that could be cool. Meaning the user with the HMD could control a robot with head-tracked stereo cameras. That part would be fun. But it seems the people on the other end would lose something because they couldn't really see the person with the HMD. I mean, the Vuzix Wrap line at least look respectable, but nothing beats eye-contact.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by PalmerTech »

brantlew wrote:PalmerTech - No I have never owned or even tried an HMD of any kind. The main reason I am focusing on Vuzix is because video teleconferencing is a 2-way deal and wearing a helmet or gigantic box on my head would be both embarrassing and distracting for the person on the other side. The Vuzix (while having some quality faults) at least attempts to provide a presentable form factor.

I would welcome any help on these matters. I am a skilled programmer and well versed in 3D graphics but a lot of these optical concepts are very new to me. If you are interested in my telepresence project I have a detailed blog about it here:
http://teledev.blogspot.com/2011/07/diy ... art-1.html.

It works just fine now, but at some point I would like to add HMD support to it.
I would look into the Cinemizer OLED, it comes out early next year. It has a similar form factor, but uses OLED displays, and will almost certainly be higher quality than any Vuzix products. Also look into the older (But still servicable) Olympus Eye-Trek series, that could work well, too.

I think Cyber is right, though, eye to eye contact seems pretty important. Perhaps a monocular HMD over just a single eye?
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by Syntax »

Palmer I think I ve found the the best display panel we should use for future DIY HMDs.

watch this video:

http://www.youtube.com/watch?v=tX92NLpr7tg&feature=fvst" onclick="window.open(this.href);return false;

It even surpasses the vision of the human eye :shock:
For Example the display of the IPhone 4 has a pixeldensity of about 326 ppi...
where as this prototype-display has a pixel density of 458 ppi !

they said that this panel will be used in camcorders and stuff. So shouldnt be to expensive to buy.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by brantlew »

Cyber, I don't want to stray off topic, so I'm moving the telepresence discussion over to another thread...

http://www.mtbs3d.com/phpBB/viewtopic.php?f=120&t=13749" onclick="window.open(this.href);return false;
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by Johnny-Mnemonic »

Syntax wrote:Palmer I think I ve found the the best display panel we should use for future DIY HMDs.

watch this video:

http://www.youtube.com/watch?v=tX92NLpr7tg&feature=fvst" onclick="window.open(this.href);return false;
Whoa... perfect thing to put into MRG2.2 shell!
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by cybereality »

Johnny-Mnemonic wrote: Whoa... perfect thing to put into MRG2.2 shell!
Only problem is the auto-stereo screens usually have a fixed distance needed to view them at. For example, for the 3DS its about 10 inches. So that may not work too well in an HMD.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by WiredEarp »

Is that actually autostereoscopic tho? The video says 'circularly polarized' film. I think it requires passive, polarized glasses.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by Johnny-Mnemonic »

cybereality wrote:
Johnny-Mnemonic wrote: Whoa... perfect thing to put into MRG2.2 shell!
Only problem is the auto-stereo screens usually have a fixed distance needed to view them at. For example, for the 3DS its about 10 inches. So that may not work too well in an HMD.
But this is not auto-stereo, it have different polarisation on each odd line, and you need to look at it through polarized glasses.
I think the same approach like in the Zalman screens.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by Okta »

Johnny-Mnemonic wrote:
cybereality wrote:
Johnny-Mnemonic wrote: Whoa... perfect thing to put into MRG2.2 shell!
Only problem is the auto-stereo screens usually have a fixed distance needed to view them at. For example, for the 3DS its about 10 inches. So that may not work too well in an HMD.
But this is not auto-stereo, it have different polarisation on each odd line, and you need to look at it through polarized glasses.
I think the same approach like in the Zalman screens.
The same is true with required viewing angle/distance on either.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by pierreye »

Since you are splitting the screen half for each eye, you might want to look at Lumagen Radiance Mini 3D. I found out it had an option to take any 3D input and output it in any format you want including SBS. You can also scale and change aspect ratio for your output so you can have a correct aspect ratio in SBS mode.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by Okta »

Nice gadget but 2k is a bit much for most diy budgets i imagaine.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by pierreye »

The mini is around USD 1.6k. I'm getting one unit for my projector and in the near future, maybe with Sony HMD since I don't think it come with complete greyscale tuning and CMS for critical viewing. I understand it's expensive but I can't see a way to use Nvidia 3D Vision with DIY HMD without a device such as Lumagen Radiance.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by foisi »

I have a few more questions about your prototypes :)

1) you are using a diffusion filter, is it really making a difference ?
1.1) where did you find it :) ?
1.2) if it blurs the image, doesn't our eyes try to make focus and since they can't get a clear image, they get strained ?
2) how did you cut the edges of the lenses (are they made of glass ?)
3) how did you make the lens mounting ?
4) can you post close (2D) pictures of your prototype (to see what you can see into one of the lens (if possible with and without the filter)) ?
5) how did you calculate the diagonal FOV ?
6) how did you set the focusing distance to 12 feet ?
6.1) for your next proto PR3 do you plan on making it adjustable ? (or is it fixed to your sight ?)
6.1.1) if yes will it be adjustable for both eye at the same time or independently ?
7) in the answer to Okta
4) I need to calculate that (Have someone making a program that projects a grid that lets me test) ...
I don't understand how you would proceed :oops: can you explain this please :)

Sorry for asking so many questions, I didn't have so many when I clicked the Post Reply button :p
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by bobv5 »

Wow, been away for a while, this is great to see.

A few questions.
1: You said "I was able to make them out of off the shelf parts, more or less." This implies that some parts are not from the shelf. Are substitutes easily available? If yes, how do they compare to the parts you used?

2a: 640x480 is really quite a low resolution. I have no doubt that the fov makes up for it in many applications, but I would like to be able to use it with a mrg style lens for flight sim's, so that I can trade the stereo for higher resolution. Assuming I can find a lens with the correct specification, would it be possible to fit a mrg style lens in place of the leep lens, or your 60 degree alternative, without making my eyes bleed? (one foot apparent distance is fine for me, though I know many would not like it)

2b: How big do the pixels look? Golf ball? Tenis ball? Basket ball? Small moon?

3: How does the pr2 compare to the wide5 in terms of fov? I know the numbers, I mean how different does it feel when you are in the simulation?

4: You list the fov as 120. I assume this is when running in 640x800. Do you have any idea of the fov when running in 640x480?

Cheers for designing this thing!
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by foisi »

bobv5

I think I can answer your question #2b :
with 120° diagonal FOV for 640x800 resolution
there is sqrt(640^2 + 800^2) ~= 1024 times the size of a pixel in the diagonal of the screen.
now in angular resolution it means that one pixel takes 120/1024 ~= 0.12°

0.12° angular resolution can be represented by an object of about 2mm at a distance of 1m
( tan(0.12/2) * 2 * 100 ~= 0.21cm )

or a golf ball at 40m (130 ft) or a basket ball at 230m (750 ft)
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by InvaderZIM »

Oh these are so cool! just stumbled to these from another thread I was reading here. I would love the opportunity to try them out. Heck I'd love to purchase a set from you if possible! Just wanted a head mounted HMD with wide FOV and a head tracker for over 20 years now and this homeade project comes closer to anything out there for the average guy.

This is a great design acheivement, and I love the LEEP style optics, I simply can't imagine what 120 degree FOV will look like through them, but I suspect it's amazing.

P.S. Make a thread for the PR3!!! :woot
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by PalmerTech »

Posted a thread for the PR3: http://www.mtbs3d.com/phpBB/viewtopic.p ... 79&start=0" onclick="window.open(this.href);return false;

@Syntax: That could work with an MRG2.2, but for something like this, you need a display that puts the center of the view in front of each eye. Yes, you can get away with converging (Like the My3D for the iPhone), but it ruins a lot of the effect.

@Pierreye: Very interesting gadget. Of my own budget, but I will see if my work will buy one. ;)

@Foisi:

1) Yes, it does make a difference. Works fine without it, but you are able to see the individual pixels if you look closely.
1.1) You are going to laugh... I got it out of an old Powerbook G4 LCD. :lol: The backlight has a number of diffusion elements, and one of them is very fine grain. I have my hands on some diffusion material that is used in the Wide5, going to be trying that next.
1.2) Blur is a bad way to describe it. It just diffuses the light a tiny bit, your eyes do not strain. Besides, suppose you are looking at a blurry image on a computer screen: Do your eyes strain to focus? Nope!
2) These lenses are acrylic, but we have a diamond saw at my work for when we want to cut lenses.
3) I made the lenses using a vacu-form mold, same way the original LEEP shell was made.
4) I will take some pictures when I get the chance.
5) I calculated the diagonal FOV with the help of the tracking system we have at work. We have a virtual environment with a grid, and you can move the HMD around, noting at exactly what point the grid lines are not visible anymore.
6) Fun trick: You use a DSLR camera, and point it into the lens of the HMD. You see, most DSLRs are cable to tell you what distance the focus is set at! Just adjust the focus until you can see the pixel grain, and you have the distance of the display.
6.1) The PR3 is not adjustable on its own. It does, however, have a swappable lens faceplate! If you made a faceplate with adjustable optics, then yes, you could have it. I do not think it is really needed, though, LEEP lenses are very tolerant of eye spacing and relief.
7) Same as 5. It is not a good "budget" way to calculate it, I know, but it is extremely accurate.

@Bobv5:
1) The parts that are not off the shelf were made using a vacu-form mold. You cannot go out and buy them, you have to make them yourself (Mainly the lens holding assembly).
2) It is a pretty low resolution, but you can get around that somewhat if you are willing to stretch the image a little bit vertically. As for making a 2D version, it would be a piece of cake! The PR3 has swappable lens faceplates, if you want, I can make a few 2D faceplates using actual MRG optics, and a few alternative lenses. This would make it very similar to the PR1. One foot apparent distance is definitely possible, but I would consider 3 feet or so to be the bare minimum for usability, something I believe I can accomplish.
2b) Foisi gave you a great technical answer. The pixels are actually very, very small. Without a diffusion filter, you can not see individual pixels so much as the image having a slightly grainy overall look. With the diffusion filter, you can not even pick out individual pixels, they are invisible to the naked eye. I know it sounds low, but this panel is much higher quality than most microdisplays, and the resolution actually looks very nice. Recall that the MRG2.2 was about a fifth of the resolution, and people still like it!

3) I am still doing tests with this. Right now, it is very, very promising, and I would say that you have 70-80% of the immersion when using the PR2. The most important thing is that you have pitch and rotation tracking, and that the virtual FOV perfectly matches the FOV of the HMD, so that objects look life sized. Not to brag, but the PR2 actually has better color reproduction and contrast compared to the Wide2, and it certainly shows. FOV is much more important than those things, though (I mean, people still feel "immersed" in the real world when they wear tinted sunglasses, which ruin your color and contrast). The other exciting thing is that I might be able to push the FOV of my system up near 140 degree FOV, which would put it very, very close to the Wide5. More as it develops.

4) Actually, the edges of the screen are touching the edges of the lense, so even in 640x480, you still have almost the same FOV, somewhere between 115 and 120 degrees. You only lose a little bit of vertical FOV! Only about 640x720 of the display is visible if you strain your eyes to see, more likely is 640x640.

@InvaderZIM: Consider yourself on the list to try these things out, once I make some more improvements. If you like them, a good review would really help, and if a lot of people are interested, maybe I could see about making more to sell (Maybe a kit?). My goal is not really to make money, obviously, or I would not be telling everyone exactly how it works! :lol: That said, it would be nice to sell some HMDs to VR enthusiasts. Made a thread for the PR3, go see it!

Phew, all replied! Sorry for taking so long to do so! Let me know what you think.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by bobv5 »

Not bothered about building the case for it, I pretty much expected that. The diffusion filter, can they be pulled from other laptops? Or bought somewhere? (will have a look for myself later, but decided to ask while I am typing this anyway)

Would be good if you can test out some 2d lenses, but no need to rush. If the panels are still available when I save up some cash I will build the 3d version first anyway. Vitrolight ebay page says he has 8 left, and I have no idea if he will get more :cry: The problem with the low res in 3d is that the instruments in any simulated vehicles is impossible to read. When I said 1 foot, I only meant that I could cope with it, not that I wanted it. Not sure if I made that clear. I do wonder though how it would even look in 2d, with the interior of vehicle suddenly being spherical! It looked a bit odd on the low fov hmd's, but everything looks odd at 30fov.....
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by PalmerTech »

Yes, they can be pulled from almost any LCD screen. However, they are all different, and work with varying degrees of success. They can be bought from 3M, but only in larger rolls, I believe. I will look into seeing if their sample sizes are enough.

Hopefully Vitrolight gets more... It seems to be run by a different person now. Jianbo is the name of the guy who used to run the store, but someone else is responding to my queries now, and they do not seem as knowledgeable. :( Luckily, the panels are available elsewhere. The control boards are actually made by a company called Roward, all Vitrolight does is program them. Worst case scenario, we might have to get a group buy together for panels and control boards.

And ah, I can see where that is a problem. And what do you mean by speherical? In terms of the wide in-game FOV, or the view through the lenses?
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by Bishop51 »

So how do I get on that list? :) See, you've got me second guessing my Sony HMZ-T1 purchase now in favor of something homebrew from Palmertech! The FOV sounds absolutely insane and you would be the most qualified person to tell us how it stacks up against far more expensive systems. If it even touches on a Wide-5 system...I mean, WOW!

I'd be absolutely fine building my own housing for it. Where do I send money? :)
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by bobv5 »

I mean like I am sat in a giant hamster ball with the inside of a car or plane painted on it. Can't think of a better way to explain.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by fraherd »

count me in. Who wants the money and how much? :mrgreen:
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by PalmerTech »

@Bishop51: Consider yourself on it! :lol: I would not be comfortable taking money at this point, though. In a few months, when I have the design all nailed down, it is a lot more likely. The housing is actually really easy to make, the hard part is the head mount! I think I am going to make my future prototypes with night vision goggle (NVG) mounts, since they are standardized and will let you use a wide variety of head/helmet mounts. Not sure if you would want to choose this over an HMZ-T1 at the moment, though. It is a lot easier to find HDMI 1.4 3D sources these days, this is definitely a homebrew option. Either way, once I have a few spare prototypes, I will mail 'em around to some of you guys so I can get feedback for design improvements.

@Bobv5: Ah, gotcha. It is a pretty cool feeling! The best way to describe it is how the world looks through a set of large pair of ski goggles.

@Fraherd: See above. Maybe it would be "better" to sell them now, before the HMZ-T1 comes out, but I want to make sure my design does not have any big flaws, and that I have the capability to provide some manner of after-sale support.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by Okta »

Would be cool if you make a semi kit, with links to easily available parts and ship out customs parts or hard to get things like the lenses.
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by foisi »

Thanks for all these answers PalmerTech :)

If you agree to sell me a set of your lenses so I can test it with my 7.2" panel and compare with the aspheric lenses I would be very pleased :)
(tell me how much money with the shipping cost to France)
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Re: PR2, a DIY, low cost, high FOV stereoscopic HMD

Post by InvaderZIM »

Man, I thought 120 degree FOV was amazing, if this design can be pushed close to the Wide 5 to 140 degree FOV..... Somebody get me a towel to wipe the drool off my keyboard. :lol:

I'm hoping the resolution of this current PR3 design will work well with my flight sims, I do have a concern that it may be on the low end, but I can see how the design of the PR3 might mitigate some of that. This will be fun!
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