development of Beamsplitter and Smartphone HMD.

[simonjosefs]

Hi!

I have just moved my litte DIY project from my kitchen table to the internetz to share what I am doing and to maybe get some feedback.

Five years ago i got interested in stereographics, and especialy making rigs to shoot Stereo-photos and videos with a single camera.

I have worked on and off with this project and now starting to feel like i have something solid, that works and is fun to use.

Im intersted to hear what you have to say about this? I could see it be used together with Oculus Rift.

Link to a CAD-rendering of the Beamsplitter: http://goo.gl/rTWuX5

I have built a prototype from this CAD-model that works.
Also made it possible to attatch a smartphone to this "stereobox" bad name for it perhaps, got any other ideas for a name?


I am also in the final stages of a Smartphone HMD where the smartphone is attached infront of your eyes with lenses between.
This is something i started with four years ago but with the use of printed stereo-photographs instead of a smarphone.

If there is anyone here that would like to try to port their Oculus rift app to Iphone and Android device (phone-size)
I could send you a prototype of my smartphone HMD.

What do you think of using AR-tags as a user-imput for a Smartphone HMD?

I believe that its possible to place one AR-tag on a table to get a fix-point an another AR-tag on a Pen to enable free 3D drawing. This would be so awesome!
Do you know of anyone who could make that work?

Cheers!

/simon

[Fredz]

Im intersted to hear what you have to say about this?
Link to a CAD-rendering of the Beamsplitter: http://goo.gl/rTWuX5
I have built a prototype from this CAD-model that works.

Interesting, did you use first surface mirrors for your beamsplitter ?

[simonjosefs]

Im intersted to hear what you have to say about this?
Link to a CAD-rendering of the Beamsplitter: http://goo.gl/rTWuX5
I have built a prototype from this CAD-model that works.

Interesting, did you use first surface mirrors for your beamsplitter ?

I used 1 mm thick common glass mirrors. It did´nt give double reflections, but it makes a thin distorted line between the left and right image. This line gets obscured and are not visible when i use my Head Mounted Smartphone Display (HMSD). I call my version of this Viewbox because looks kinda like a box strapped to your head with a smartphone attached infront of your eyes.

I have ordered first surface mirrors to try this out as well. but the price is pretty costly. this could make the final product too pricey.
Do you know of anyone who sell first surface mirrors?

What do you think of this beamsplitter with the use together with oculus rift?
The field of view with the beamsplitter is aproximately 75-80 degrees in lowest zoom setting on the camera.
Stereodepth is 65 mm.

[Fredz]

I have ordered first surface mirrors to try this out as well. but the price is pretty costly. this could make the final product too pricey.
Do you know of anyone who sell first surface mirrors?

You can make them yourself using common glass mirrors with this technique :

http://www.youtube.com/watch?v=Ot4VUKEevJg

What do you think of this beamsplitter with the use together with oculus rift?
The field of view with the beamsplitter is aproximately 75-80 degrees in lowest zoom setting on the camera. Stereodepth is 65 mm.

The interaxial looks very nice at 65 mm, the Oculus Rift has a 64 mm separation between the center of the lenses.

The FOV is a bit short but I guess it can still give interesting results. I suppose 75-80° is the horizontal FOV, what is the vertical FOV ? AFAIK, the Oculus Rift has a 114.5° horizontal FOV and a 125.5° vertical FOV (default values of the stereoconfig class in the SDK).

You may have a look here for an interesting discussion about beamsplitters for the Rift :
http://www.mtbs3d.com/phpbb/viewtopic.php?f=140&t=15938

[simonjosefs]

The FOV is a bit short but I guess it can still give interesting results. I suppose 75-80° is the horizontal FOV, what is the vertical FOV ? AFAIK, the Oculus Rift has a 114.5° horizontal FOV and a 125.5° vertical FOV (default values of the stereoconfig class in the SDK).

Thanks for that vid! could come in handy in the future.

I have just ordered convex mirrors that will replace the outer flat mirrors. just to see how much larger field of view this would give.
If it´s anything close to 125° FOV It would bee a perfect match for Oculus rift.
My guess is that these convex mirrors would give more than 125° FOV which would enable headtracking since some of the image would be outside of the oculus rift edges.

Have you seen any beamsplitter similar to my idea where it is mounted on the tripod nut?

[Fredz]

Have you seen any beamsplitter similar to my idea where it is mounted on the tripod nut?

I watched the picture too quickly and didn't remark that the beamsplitter was mounted on the tripod nut, very clever. Nope I haven't seen beamsplitters attached like this before.

[simonjosefs]

the Oculus Rift has a 114.5° horizontal FOV and a 125.5° vertical FOV (default values of the stereoconfig class in the SDK).

Do you know in what way the image is distorted in the Rift?

[Fredz]

It's a pincushion/barrel distortion, you can find more info about it here :
http://rifty-business.blogspot.fr/2013/ ... rtion.html

[simonjosefs]

thanks!