Experimental HMD for LG G3 android quad HD phone

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skyehog
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Experimental HMD for LG G3 android quad HD phone

Post by skyehog »

Having recently upgraded my phone to the LG G3 which boasts a fantastic 2560 x 1440, Quad HD screen I built this HMD so I can test out some of the results of my dabbling with VR using Unity. As I don't want to have to make another unit for each set of lenses I try, I have built in a means to easily swap between sets of optics. Having used (a generic version of) the Google Cardboard idea I also wanted something more comfortable which was akin to the Rift and have incorporated a ski mask mount.

I was one of the early recipients of a DK1 and, having been fascinated with stereo 3D & the concept of VR for years it blew me away. However I was soon frustrated by the need to be wired up to a PC and I became fed up of carting around lots of gear in order to show off the concept of VR to friends & family.

I had been away from this forum for a while (having watched the rift grow from pre-Kickstarter days to receiving my own) and returning recently in search of pointers towards a more portable VR solution I was thrilled to see so many people playing around with this concept at a DIY level and beyond. Amongst others, two of my main inspirations have been Stefan Walker with his Durovis Dive (and Unity Dive Plug In) as well as Trevor Walker's Playstep3dVR concept.

My hobby HMD doesn't begin to approach the polished accomplishment of these devices, let alone the new Gear VR, but I thought I would show it off in the hope that other DIY Mobile VR enthusiasts might be able to use some of the design or simple, readily accessible construction ideas.

A few more pics & details to follow...
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skyehog
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Re: Experimental HMD for LG G3 android quad HD phone

Post by skyehog »

The unit is built from foam core board (from Hobbycraft in the UK) and used no more than two A4 sheets. It is basically one box to hold the optics which is mounted to the ski mask (which was less than a £ tenner from SportsDirect) with cable ties, and a second frame which holds the phone. The phone is held in a slot cut to size with velcro straps and the position of the phone mount component is locked to the lens holder / face mask part with velcro also.

The lenses in the unit are the well known, x5 aspheric units which many folk are using for HMDs such as this. They are mounted (with hot melt glue) to a removable piece of foam core, the idea being that any other lenses, assuming they are mounted to a similarly shaped piece, will fit straight in. The phone / display may then be moved backwards & forwards to achieve focus before being velcro locked into place.

Having tried superglue to fix the thing together (and finding that it melts foam core really well) I reverted to hot melt for the fabrication of most of the unit. Good old duct tape also plays a part.
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skyehog
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Re: Experimental HMD for LG G3 android quad HD phone

Post by skyehog »

The lens holder is locked into the unit with a couple of 'keys'. It tucks under the brow of the molded mask assembly and the keys wedge it in place.
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skyehog
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Re: Experimental HMD for LG G3 android quad HD phone

Post by skyehog »

Granted, the whole thing is a bit rough & ready, but it allows me to explore the potential of the phone display and mobile phone VR in general whilst playing around with different optics without endless re-builds.

I have to say though that as far as the x5 loupes go for a screen of this size I am a bit disappointed. The FOV isn't a patch on the DK1 (I haven't had the pleasure of trying later incarnations of the Rift) and the screen edges are clearly visible. I would liken the experience to looking out of a full-face motorcycle helmet - a feeling of looking out at the world, with the necessary peripheral vision to navigate around, but not enough FOV to forget that one is looking 'out through' something.

I have read (and have still to read a lot more) on this forum about lens options for units like this, but would be interested and grateful for input as to tried and tested, low cost alternative lens options for such 5.x" screes like this. The Openloop thread here on MTBS3D mentions this one (x7); http://www.amazon.co.uk/Ultra-Optix-SV- ... ultraoptix and this one (x30 I think !); http://www.ebay.co.uk/itm/Jewellers-Jew ... 20f0a0d4a6 There are also interesting comments elsewhere about cheap fresnel lens stacks.

The lenses currently in the unit are these; http://www.ebay.co.uk/itm/5x-pocket-lou ... 3a79987a19

I intend to try the cheaper options first and will post back how I get on.

Thanks for looking

Nick
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Re: Experimental HMD for LG G3 android quad HD phone

Post by Hannibalj2 »

The fact that you are fiddling around creating your own HMD helps appreciate the complexities that involves making a good Headset.

It will be great that you can get it to work successfully. I am curious about the pixel density of the LG display. It has full sub-pixels so it should be better at diminishing screen door effect than the Note 4.

Nice going mate. Best, I hope you get it all working! ;)
Last edited by Hannibalj2 on Wed Nov 19, 2014 9:09 pm, edited 2 times in total.
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Re: Experimental HMD for LG G3 android quad HD phone

Post by skyehog »

Thanks Hannibalj2

The G3 is certainly a fabulous display and the clarity of image through the current lenses is pretty spectacular with negligible screen door at this magnification. I am still tinkering with the phone to improve the frame rate but overall the resolution itself is (unsurprisingly) a massive improvement on the old Rift DK1. I feel that I have achieved what I set out to do so far, which is to put together a useable and configurable headset to allow me to explore the results of application development at my very basic skill level. It would be nice though to more closely recapture that sense of presence which the Rift offers. I look forward to learning more about the optics in the GearVR in the hope that we tinkerers can replicate something similar with card & duct tape !
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Re: Experimental HMD for LG G3 android quad HD phone

Post by Dilip »

@skyehog

Can you post image captured through those lenses?

Here is also nice infamous square optics
http://www.amazon.co.uk/Carson-MiniBrit ... =carson+5x

They are known for very very low distortion you can see them in working............
see the insanity of 7X lenses aka DK1, lots of distortion and big amount of chromatic aberration where as Carson is just Fantabulos.
http://www.youtube.com/watch?v=3NtPAKTLbQk

Only grip is its square..but as you have lenses holding assembly easily coming out kind of moduler you can surely try this. i doubt though focal length may need workout.
With G3 screen its most rewarding for sure....

I will even suggest oculus to include this lenses as additional pair they are already providing two sets for vision correction whats wrong in adding third one for one real all sbs supporting HMD will also include people who want bigscreen but not much in to VR its absolute win win As Carson Made in china they can get them self those 6X custom made which will make offer even more lucrative. which can work with even those game that are not made for VR........ That's too big list and i can vouch for TRIDEF they work WOW.
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Re: Experimental HMD for LG G3 android quad HD phone

Post by skyehog »

Here are some stills through the display - as close as I could get to the lens with a Fuji HS30EXR camera set to 50mm focal length. These are taken from the Shadowgun VR app by Egidijus Infinitus on the Google Play Store here; https://play.google.com/store/apps/deta ... us.VRscene This is by far the best imagery I have seen for mobile VR I have yet managed to find on this platform.

I will add a link to YouTube footage of the head tracking once the file has uploaded to YouTube which is taking FOREVER with my slowish connection ......... oh, hang on, here it is; http://youtu.be/aiLNTo5cMaM The circular boundary of the lenses is not visible with the HMD in place, although the edges of the screen are, as previously mentioned & hence my continued quest for more suitable lenses.

Ordered a couple of these; http://www.ebay.co.uk/itm/Jewellers-Jew ... 20f0a0d4a6 today, as mentioned here; http://www.mtbs3d.com/phpBB/viewtopic.php?f=138&t=18441 by thirty3baboons.

May also try these; http://www.amazon.co.uk/Ultra-Optix-SV- ... ltra+optix

...and something like these; http://www.ebay.co.uk/itm/MAGNIFIED-BOO ... 19eaf5c860 ...stacked as in this thread by geekmaster; http://www.mtbs3d.com/phpbb/viewtopic.php?f=138&t=16373

I'm very appreciative of all the hard work put in by these folks and shared for the benefit of clueless dabblers such as myself by the way !

Really happy with the image quality from this phone. 'Just' need to improve the field of view, even at the expense of a little resolution. I will post more if I make any significant progress.
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Dilip
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Re: Experimental HMD for LG G3 android quad HD phone

Post by Dilip »

Images are CERTAINLY BETTER THAN NOTE 4 even if though its LCD Vs Note 4's OLED.

@HannibalJ
Thanks for posting Note 4 images in your thread.
http://www.mtbs3d.com/phpBB/viewtopic.php?f=140&t=20331
Those who wish to compare side by side can do this...

As you are both using DK1 optics that's similar to 7X Aspheric i find G3 version more Crisp. ok there is slight lack in black levels but huge gain in over all quality...

One more thing noticed that Note4 OLED images has interleaved line kind of pattern which are diagonal where as LG G3 doesn't have them may be its because of PIXEL STRUCTURE of PENTILE
but it looks like diagonal interleaved image. OLED on other hand much vibrant in color. Still if there is way to avoid motion blur and G3 LCD is indeed faster,as they claim it.

Then this seems more suitable display for VR as it has more PPI being 5.5 inch other then more REAL PPI being RGB STRIP display.

@skyehog
Thanks for posting images. :D

KUDOS
Your image fidelity may BEAT GEAR VR.
Sure integration, latency and software side GEAR VR is in Win.
But your rig is awesome too. 8-)

You may want to try LIMELIGHT...
https://play.google.com/store/apps/deta ... ight&hl=en
http://limelight-stream.com/

IMHO better to Splashtop if you have GTX660 or above.
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Re: Experimental HMD for LG G3 android quad HD phone

Post by Dilip »

skyehog wrote:As previously mentioned & hence my continued quest for more suitable lenses.

Ordered a couple of these; http://www.ebay.co.uk/itm/Jewellers-Jew ... 20f0a0d4a6 today, as mentioned here; http://www.mtbs3d.com/phpBB/viewtopic.php?f=138&t=18441 by thirty3baboons.

May also try these; http://www.amazon.co.uk/Ultra-Optix-SV- ... ltra+optix

...and something like these; http://www.ebay.co.uk/itm/MAGNIFIED-BOO ... 19eaf5c860 ...stacked as in this thread by geekmaster; http://www.mtbs3d.com/phpbb/viewtopic.php?f=138&t=16373
Regarding your suggested optics.

1.
http://www.ebay.co.uk/itm/MAGNIFIED-BOO ... 19eaf5c860

Fresnel is Bad choice see here why....
http://www.reddit.com/r/oculus/comments ... _the_rift/

2.
http://www.ebay.co.uk/itm/Jewellers-Jew ... 20f0a0d4a6

Again bad choice,will induce hell amount spherical distortion for sure. can be good if you can correct distortion or are OK with distortion or have utility that are made for RIFT.

3.
http://www.amazon.co.uk/Ultra-Optix-SV- ... ltra+optix

Mostly Same as DK1 lenses you are using....Hardly any difference but are best out of all you mentioned.
.
.
.
Why don't you try this.....Sure it will have little less FoV but visuals will be blast.....
http://www.amazon.co.uk/Carson-MagniBri ... =carson+5x
.
These will be another good option i already posted video comparison.
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Re: Experimental HMD for LG G3 android quad HD phone

Post by skyehog »

Thanks for your ongoing input Dilip

I put a set of the loupe lenses in the headset yesterday.

They are supposed to be x30 but are closer to x10. While the eye relief on these is so small that they have to be crammed against the eyeball, I can see that x10 is closer to where I need to be. I would be interested to try the lenses you suggest but as I know I need a higher magnification and am on a budget I am looking for another solution (I guess I could try combining them with the x5 lenses I already have though ...).

Today I slid a cheap credit card sized fresnel magnifier in front of the x5 lenses in the HMD and this combination gets me MUCH closer to the kind of FOV I am hoping to achieve whilst allowing a reasonable eye relief distance. However, as we know, fresnel lenses present their own problems and image quality suffers a little with this approach. I do have a pair of cheap, 3 inch glass magnifiers with reasonable optical clarity though and I intend to stack these with the existing x5 lenses & see what happens. Initial tests just holding the stacked lenses over the phone suggest that this might be one way to get the results I want without spending any more cash at this stage. It will add weight though so the hunt for large diameter, x10-ish, cheap lenses goes on
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Re: Experimental HMD for LG G3 android quad HD phone

Post by Hannibalj2 »

I have to agree, that the pixel density of the LG3 is better! I really like the image quality. I think that the colors on the Note 4 are richer. I am curious, what is the refresh rate of the LG3 display. That is one of my concerns with the display.
Graphical quality is superb! Nice work! :)
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Re: Experimental HMD for LG G3 android quad HD phone

Post by skyehog »

Hannibalj2 - There are some details on the screen here; http://www.anandtech.com/show/8169/the-lg-g3-review/2

As far as frame rate goes, I don't profess to have a grasp of the details but I understand that the phone varies the rate depending upon the demands placed upon it. That said, there is rumored to be a way of locking it to 60fps in developer options. I have tried to do this but despite selecting the 60fps option I am unable to make the setting stick (I'm not alone I don't think).

As it stands just now the display is undeniably 'stuttery'. Not noticeable to the naked eye but through the levels of magnification we're talking about here it is certainly an issue without 60fps locked. What it's actually running at I couldn't say. Unsurprisingly there is latency. Not so noticeable with slow head movements but moving rapidly left to right it's there.

Thanks for the support by the way !
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Re: Experimental HMD for LG G3 android quad HD phone

Post by 13thFloor »

I can certainly appreciate the mileage you have faced with this. I have a 1440p screen and MPI board and have been sitting with off the shelf HMD headsets seeing what works best and where to go.

The foam route seems pretty good for building up layers and getting to what you want. I might try that.

Resolution I think 1440p is a great starting point for a HMD for video or VR.
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Re: Experimental HMD for LG G3 android quad HD phone

Post by konstantin_lozev »

Hi, nice build, on lenses, why don't you try the OpenDive lens kit. The lenses are quite small, but the magnification is bigger than the cardboard ones that I think you are using.
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Re: Experimental HMD for LG G3 android quad HD phone

Post by skyehog »

A quick update...

I am still playing around trying to maximise the FOV I can achieve with this phone and have amassed quite a collection of lenses...

Until recently, the best I had managed to achieve was with a pair of these glass plano-convex lenses...
lenses.jpg
These deliver a pretty wide FOV & good image quality at the centre but there is significant blurring towards the edge of view. In addition a black border is still present at the sides though it isn't too bad. The lenses are pretty heavy too.
hmd1.jpg
hmd2.jpg
For a while this is as far as I took the project while I concentrated on messing around trying to create some content with Unity & Blender.

A week or so back I had another play around and started hacking around the original Cardboard I had purchased (a larger format one for bigger phones from some guy on EBay months ago). The lenses which came with this thing were 30mm biconvex acrylic and quality was poor with some fine scratches and general blurring of parts of the image. Nonetheless, I tried pairing them up with other lenses in my growing collection !

So far the best I have managed to achieve (in terms of FOV, not image quality !) is a 'stacked' arrangement of these 30mm and a fresnel 'magnifying bookmark' lens such as this..
$_57.JPG
As with so many of these cheap lenses, information varies on the supposed focal length / magnification, but from what I can tell, FL seems to be in the region of 130mm-ish, so close enough to x2. The 30mm lenses (bigger than most G.C lenses which tend to be 25mm), seem to be roughly 40 - 45mm FL (based on my ham fisted measurements), putting them at about 5.5 to 6x or so.

The 30mm lenses are hot glued into the top of milk cartons for lens cups and the fresnel is simply slid through slits cut in the side of the unit (after a bit of measuring to get the focus right).
gcbmod1.jpg
gcbmod2.jpg
The FOV delivered by this VERY rough set-up is impressive. The magnification of the screen is slightly greater than with the glass lenses and there is very slight clipping of the horizontal image. There is also a curved, black, 'blinker' shape visible at the outermost edges of the image, although this is much less distracting than the vertical black bar seen through the glass lens setup. Immersion is very good for such a simple arrangement and (though it's a while since I got rid of my DK1 so I'm working from memory) I would say that FOV is approaching the 1st generation Rift. Image quality through the combination of crummy acrylic Cardboard lenses and the cheapo fresnel (which is itself a bit scuffed from me sliding it back & forth through the slits in the cardboard) isn't the greatest although the sharpness of the image is much better than with the plano-convex glass lenses with little or no blurring to the extremities of the image.

I am sufficiently encouraged by the results of this to date that I have ordered some of these lenses;
1006745.jpg
http://www.edmundoptics.co.uk/optics/op ... ses/77154/ in an effort to improve image quality by doing away with the fresnel. These lenses are 75mm square and of very similar focal length to the bookmark magnifier. Side by side the pair will pretty much cover the full width of the G3 screen and act as my objective lenses.

For eyepieces I have a set of these on the way;
au.JPG
http://www.ebay.co.uk/itm/171446562158? ... EBIDX%3AIT which will hopefully deliver the same FOV & magnification as the acrylic Cardboard lenses I have been using but with much better image quality. I already have a set of 42.8mm fl x 25mm dia glass lenses of high optical quality and, while I feel these are too small in diameter to deliver the FOV (and / or eye relief) I am after, the clarity of image from them (even coupled with the fresnel) is such that I am hopeful of some good results when the lenses arrive through the mail.

Watch this space.....
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Re: Experimental HMD for LG G3 android quad HD phone

Post by Dilip »

I know i sound greedy, but do post through your new setup screen images once you complete it. Nice to see active poster here. :)
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Re: Experimental HMD for LG G3 android quad HD phone

Post by skyehog »

I will be happy to post some images up through the new rig once I have something cobbled together.

In the mean time I have put the attached image together in an effort to demonstrate the variety of results through the various setups I have going on. Phone VR app graphics seem to be improving all the time but the Shadowgun VR app has been around for a while and the quality is excellent. The app starts with a fly-through before the 'player' is dropped to the ground and head tracking is activated. A large statue stands on a plinth in the centre of the space and the plinth provides a useful reference for comparing image quality and perceived field of view.

I have tried to mock up the view as seen through these various experimental rigs, as well as the Colorcross I bought a while back. I should stress that this has been done with a screenshot from the phone, cropped to show the right side image only and then edited in an effort to show image quality, blurring of the edge of the image, etc. These are not actual views taken through the HMDs but representations of them as getting accurate images / impressions of HMDs through the lenses with a camera is difficult or impossible in my limited experience.

Personally I find it difficult to estimate field of view though I'm sure there must be a way to work it out posed somewhere on these forums. I have added a red ellipse to each image in an effort to illustrate the scale of my estimation of the 'centre of gaze'. I would consider anything outside of this ellipse to be peripheral vision - the greater the amount of available peripheral vision (which may be brought into focus by moving one's eyes, the greater the perceived FOV.
lenses comparison.jpg
The first image is the full right hand image, direct from the screen shot. The quality is excellent on this quad HD phone :-)

The next image is my representation of the view through the Colorcross. The sharpness of the image across the entire filed of view is excellent and the lenses are very impressive. However, as experienced by other users, the FOV is pretty small and there is definitely a sense of looking though a frame of a window as opposed to being immersed in a real space. In addition (on my phone) each lens is picking up a portion of the opposite side of the screen which in turn appears as a vertical bar to each side of the main image and is extremely distracting. This, coupled with the black frame around the scene really impacts upon immersion. In addition the scene feels the most distant of all the three rigs shown here.

Next is the view through the plano-convex lens, ski-mask set-up. Field of view is much improved here though at the expense of clearly defined peripheral view. The lenses badly distort all but the near / mid area of this peripheral view. Image quality within this area however is very good as these are quality, glass lenses. There is a sense of being within a much larger, closer environment and the aforementioned peripheral distortion is less of a problem than might be imagined as, with head tracking, any part of the environment may be brought into focus by turning the head towards it (or moving the 'player's' point of view with a game controller). The red ellipse shows a larger available area of peripheral vision which significantly improves FOV in comparison to the Colorcross. There is still a vertical, black border to the sides of the view which does impact upon immersion to an extent and some clipping of the horizontal image means that, for example, the soldier on the far left of the scene is missing. On the whole however the results from this rig are a step in the right direction and for a while I left the project alone as I felt it was 'good enough' to use to test out android VR environments I was trying to build in Unity.

The final image is the where I am just now with the stacked lens arrangement. I have intentionally blurred the entire image slightly to reflect the dodgy quality of the cheap Cardboard and fresnel lenses currently installed. Importantly however, the image quality is consistent across the majority of the entire field of view - it just need to be sharpened up with better quality, equivalent optics. Thin, slightly convex black bars are present at the extreme horizontal edges of the image which, rather than feeling like looking through a slot, feel more like what one might imagine a horse sees whilst wearing 'blinkers'. There is a slight vignetting at the corners and some image distortion to the top of the image which I imagine could be corrected with more careful positioning of the lenses. Crucially, the field of view is further improved and the perceived scale really gives a sense of 'being there'. Again, there is slight clipping of the horizontal image (the guy on the extreme left of the view can't be seen).

I feel that this, final set up (albeit with improved optical clarity) is approaching the sense of immersion offered by the original Rift DK1. As phone screen pixel density improves I think it would be great if more experimentation could be done by the amateur VR community to see how good a result can be achieved from these phones using readily available optics in different combinations. It seems to me that, great as the Google Cardboard is for bringing mobile 'VR' / stereoscopy to the public, better immersion must be possible using other lenses. I also have a hunch that as the graphics processing power of mobile devices improves that VR focus will move increasingly towards mobile platforms. I would like to think that this would mean availability of better quality, more immersive headsets, designed to allow cross compatibility between phone handsets and manufacturers, not locked in to single manufacturers / models in the style of the GearVR.
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Re: Experimental HMD for LG G3 android quad HD phone

Post by kupfnerjw »

I wonder how many pins the LG G3 display has on it's own (the wide ribbon is for the display, the small ribbon coming off of the display goes to the touch controller). I would like to try using the display by itself as a monitor instead of the signal being routed to the phone via wi-fi. If I can find out how many pins the ribbon has, then find out if a controller kit like the VS-TY2662-V1 is compatable (even if I have to splicing/soldering), then the lcd may be usable straight up as a monitor. :woot http://i.ebayimg.com/00/s/MTAyNFgxMDI0/ ... i/$_57.JPG

If it would work (IF!), I would start building a light weight (albeit wired) hmd. Then my next leap would be getting a gyro and head tracking installed.

Thanks for all of the information that you peeps have provided. This gives me that tickly feeling inside!

Maybe I could make something like claire by VRunion this away. http://vrunion.com/#claire

It of course would be much cheaper than $2500!
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Re: Experimental HMD for LG G3 android quad HD phone

Post by skyehog »

For anyone still vaguely interested in my hapless efforts. I received the rectangular glass lenses. They are a non-starter, each one must weigh a pound !
square lens.jpg
Going back to the idea of stacking biconvex and fresnel lenses I put in orders for various fresnels from here and there.

The best combination I have managed to come up with is a set of glass, 25mm x 43mm fl lenses, sold by http://www.astromediashop.co.uk/ and recommended by the vendor as suitable for the Google Cardboard, coupled with a pair of 'credit card' type, flexible frenel lenses.
fresnel stack.jpg
The glass lenses give great image quality but the magnification isn't high enough and the screen edges are visible when the lenses are used on their own. While the fresnels dull the image a little and cause colour fringing to some extent, the overall result isn't too bad and far more immersive than the biconvex lenses alone.

I have also tried a set of 30mm lenses of a similar focal length, but the issue I am having with larger lenses is that the screen edges come into view too readily. I know very little about optics (as is no doubt evident from reading this post) and I am trying to learn more by experimentation and trial and error, but the objective here seems to be seeing all (or just a little less) of the available screen image without also seeing the edge of the screen (or the edge of the lens - or at least unacceptable distortion caused by it). I am seeking to do this by using higher magnification lenses than the stock Google Cardboard (ie 8 to 10 x as opposed to 5 to 6 x) and bringing the lenses close to the eye through use of a lens / eye cup arrangement.

I had always thought that the 7 inch screen of the Rift DK1 was a sub-optimal choice driven by the lack of availability of smaller, high pixel density screens. However, having spent hours trying to get a similar sense of immersion with this, smaller (and far higher resolution) screen, I find myself hankering for a 7 inch screen. My hunch is, that to get super wide FOV, larger diameter lenses in front of somewhat larger screens would be preferable. In that way the eye can swivel as far as possible in its socket towards the horizontal border of the screen and still have lots of screen real estate left to scan across (ie significant, available peripheral vision). These tiny phone screens, irrespective of pixel density, seem too small to give great FOV. The edge of the screen is too close, unless the FL is reduced (and magnification increased) in which case the pixels are magnified. Readily available (cheap) lenses tend to get smaller as the FL reduces & magnification increases, which then leads to the swivelling eye meeting the perimeter of the lens - unless larger diameter lenses of similar magnification CAN be sourced, in which case the swivelling eye encounters the magnified edge of the screen instead. With the fresnel lens in this, latest hmd, I am seeking to pre-magnify the screen to effectively make it appear larger to the glass eyepiece lens. This approach seems to have some potential and adds very little additional weight.

I am starting to thing that the results I have achieved here (certainly in terms of FOV, which is difficult to convey in words and images) is about as far as it is possible to go with such a small screen (5.7 inch), certainly without custom made optics. I would be delighted to be proved wrong however. If nothing else this has been a lesson in foam core board engineering !
hmds.jpg
I will try to get around to mocking up my impression of the FOV of this, latest stacked lens arrangement using Shadowgun as in the examples above. This lens combination, while not perfect (slim black bars are still visible at the outer screen edges) has delivered the greatest sense of 'presence' of all the DIY setups I have tried to date.
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skyehog
One Eyed Hopeful
Posts: 14
Joined: Sat Jun 30, 2012 6:09 am

Re: Experimental HMD for LG G3 android quad HD phone

Post by skyehog »

Just had another peer at Shadowgun through the latest lens config and there isn't a huge difference between this and the final (~45mm fl plus fresnel) image in the comparison above - again, this seems to be the best I can come up with....

Would love to hear what other folks have managed to achieve hacking their Cardboards or building rudimentary, phone based HMDs.
Ryuuken24
Cross Eyed!
Posts: 117
Joined: Fri May 17, 2013 6:49 am

Re: Experimental HMD for LG G3 android quad HD phone

Post by Ryuuken24 »

13thFloor wrote:I can certainly appreciate the mileage you have faced with this. I have a 1440p screen and MPI board and have been sitting with off the shelf HMD headsets seeing what works best and where to go.

The foam route seems pretty good for building up layers and getting to what you want. I might try that.

Resolution I think 1440p is a great starting point for a HMD for video or VR.
Hey, may I ask how you managed to get a 1440p display and a MPI board for it?
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