DIY monocular HMD - feasibility?

[cjdavies]

(Apologies that this isn't 3D stereographic related, however this forum seems to be a one of the best sources online for anything HMD related, even if not 3D sterographic.)

I've always wanted to have a high resolution monocular HMD - high enough resolution & sharp enough to display a respectable amount of readable text & a mouse pointer without it just being a small blurry blob. I've seen the various MyVu Crystal mods (like this one) but I want substantially more than 640x480.

Some searching reveals that there now exist 1920x1080 (AM)OLED microdisplays in sub 1" diagonal sizes. Is it at all feasible to take something like this & use it as the basis for a DIY monocular HMD? I realise that such microdisplays certainly won't be cheap, but my question at this stage is more to do with whether this approach is even plausible, or whether the complexity of necessary optics (or something else) would render the endeavour completely out-of-reach for a hobbyist?

I've seen the ST1080, however availability is questionable atm & I don't really want to buy one only to cut it into pieces, possibly breaking parts in the process!

[WiredEarp]

I've got a Z800 with a slightly faulty screen - was thinking of making it into a monocular at some point, so I could use it with BlackShark (flip down a screen to aim my guns, just like the real thing). It should be fine for this use, however most monocular setups would probably be better as AR, not VR devices.

The Z800 is quite readable for text etc. Its 800x600. You might want to look into seeing if you can find a similar, faulty HMD, and just buy that and cut it down (if possible), it would save you a lot of work.

The higher resolution OLED screens are ridiculously expensive from what I've seen of their pricing in the past. Easily > US$1000 each...

[cjdavies]

800x600 is still less than I want to work with. 1280x720 is realistically the minimum I would probably consider worth the investment to build

[WiredEarp]

I think you'll run into issues there. For something decently small (you don't want something deep like the rift, but just for one eye, that would look a bit stupid) you'd need a small screen. Really I think expensive OLED's might be the only way to go. Could always get a Sony HMZ and try to make out of that or the lenses - they are 1280x720. Might be selling pretty cheap secondhand with the Rift coming out

[cjdavies]

Would something like this, if available for <$500 (though I doubt that...), be suitable, if I could design/source suitable optics?

http://holoeye.com/lcos-microdisplays/h ... rodisplay/

I presume that the smaller the physical dimensions of the display, the smaller the optics can be & thus the less the unit has to 'stick out' from the face? You're right that a Rift depth solution over one eye would look ridiculous & probably be impossible to balance, so nice cheap smartphone panels are probably out of the question due to their size.

[WiredEarp]

Yeah, probably? I dont think LCOS is as good as OLED however. That screen takes standard inputs though which is what you want...

[WiredEarp]

Thinking about it, I think you'll find it way too difficult to achieve a compact design using standard lenses and even a small screen like that

The optics on the Z800 are great and very thin and lightweight - but if you replaced them with standard lenses it would probably add an extra 1-2" at least to the depth of the unit.
(total guesstimates here!).

[cjdavies]

It's beginning to look like building from scratch would end up far too expensive & complex That Holoeye dev kit I linked is £4026 (presumable before VAT) & that's only 1280x720. Think I'll just keep an eye out on auctions for old units to cut in half!

[cjdavies]

Just realised that the Z800 is VGA only - what options are there for DVI/HDMI? I'll probably want to ultimately use some sort of android device (like the ODROID U2 --> http://www.hardkernel.com/renewal_2011/ ... 5341370451) to drive the HMD, so HDMI is really the only option.

[WiredEarp]

The Z800 is actually SVGA (800x600), not VGA.
Edit: sorry, missed the real point of your post. Since you are going for single screen only (3d not required) you could use a HDMI->VGA converter. They are cheap. Might be tricky to find a lightweight one, but you could always just put one in a belt pack...

[cjdavies]

I've found cheap HDMI to VGA adaptors on ebay that appear to be passive (by size/price at least) but will this work? My instinct says no, as an HDMI output can't output an analog signal like a DVI-I can so surely the adaptor will have to be active to convert the digital signal to an analog one using a RAMDAC or something?