mrfahrenheit94's Budget HMD
Posted: Wed Jun 29, 2011 2:30 pm
Hi,
So I wanted to venture into the world of virtual reality and HMDs, but as a college student, money is not abundant.
A little about me: I learned about HMDs mainly through google searches and this forum (thanks!) and I think the most useful page that I came across was the one on vrtifacts.com called "LEEP on the Cheap" which shows how you can make LEEP style optics for a small amount of money.
LEEP optics are known for their large FOV, but because they were invented in the 80's, there weren't very high resolution displays to accompany the optics thus making the overall image quality kinda bad. Well, we're not in the 80's anymore, and I am a proud owner of the Motorola Atrix, which boasts a qHD 960x540 resolution, all in a compact 4" display. So I decided to go with that for my screen.
The first thing that I purchased were the lenses. The article on vrtifacts helped a lot when it came down to which lenses to buy. I ended up buying 32.5mm diameter plano convex lenses with a focal length of 85mm. The lenses themselves were only $11 for two, but shipping was another $11, so yeah, $22 for the lenses.
I received the lenses yesterday in the mail, and decided to play around with them. I held one lens up to my eye and adjusted the distance to the display until it became sharp. It was freaking awesome. I didn't do any calculations, but the FOV was definitely more than 60 degrees. It reminded me of an IMAX theater. The greatest part though is that although I could see individual pixels, it was a lot less noticeable than I expected it to be and the experience was so immersive that I didn't really notice.
A problem that I did notice though is that it is blurry on the corners of the display. This is due to the fact that the screen is 4". If it were say a 3" screen, it would have been better, but I didn't mind it that much.
A much bigger problem occured when I tried using both lenses at once with the same display. When there is a single object on the screen, the lenses cause the left eye to see that object shifted to the left and the right eye to see that object shifted to the right. This resulted in unwatchable 2d fullscreen videos, UNLESS I angled the lenses inward towards the screen.
The easiest solution would be to get a 2nd display and center each display on the center of each lens, but due to the size of the screen, that would be impossible because the average distance between the eyes is about 65mm. The solution to the big display problem is to make the two screens angled into a "V" shape.
So after playing around with the lenses, I made a very ugly cardboard cutout to fit the lenses and display into. The final design actually takes advantage of a plastic PSP case that seems perfect for an HMD. I modeled a 3d version of what the final HMD should look like, but it is a WIP.
Here's an exploded view of the HMD modeled in Autodesk Inventor
http://www.youtube.com/watch?v=ETZ8CgVP4nM" onclick="window.open(this.href);return false;
I was initially just going to make this a monoscopic HMD, but then my friend came up with an awesome idea: Use the side-by-side 3d method with videos and games. And it works! The geometry of the lenses happens to work out so that when looking through both lenses, I can see the left image only with my left eye and the right image only with the right eye. I tested this out with some 3d youtube videos and some of the side by side pictures on this site's homepage.
The obvious downside of the side-by-side 3d method is that it cuts the horizontal resolution in half, but it works, so I'm happy.
Here's the big question though: How am I supposed to play PC games in 3d on my phone if its a PHONE? Well, there just so happens to be an app available called Splashtop Remote which is a VNC server of sorts, but with a very high FPS. I say very high RELATIVE to standard VNC programs that run on the phone. The standard ones usually get 1fps. Yes, ONE. Splashtop gets about 15-20, which I know isn't spectacular, but it works. For those who don't know, the app mirrors whatever is visible on the monitor of the computer running the server program. So its basically a remote display.
So I downloaded the iz3d driver and set it to side by side mode, fired up Left 4 Dead, and BAM my homemade HMD was working in stereoscopic 3D.
More pics and videos to arrive soon.
Questions, opinions, etc.? Sorry for such a long post.
So I wanted to venture into the world of virtual reality and HMDs, but as a college student, money is not abundant.
A little about me: I learned about HMDs mainly through google searches and this forum (thanks!) and I think the most useful page that I came across was the one on vrtifacts.com called "LEEP on the Cheap" which shows how you can make LEEP style optics for a small amount of money.
LEEP optics are known for their large FOV, but because they were invented in the 80's, there weren't very high resolution displays to accompany the optics thus making the overall image quality kinda bad. Well, we're not in the 80's anymore, and I am a proud owner of the Motorola Atrix, which boasts a qHD 960x540 resolution, all in a compact 4" display. So I decided to go with that for my screen.
The first thing that I purchased were the lenses. The article on vrtifacts helped a lot when it came down to which lenses to buy. I ended up buying 32.5mm diameter plano convex lenses with a focal length of 85mm. The lenses themselves were only $11 for two, but shipping was another $11, so yeah, $22 for the lenses.
I received the lenses yesterday in the mail, and decided to play around with them. I held one lens up to my eye and adjusted the distance to the display until it became sharp. It was freaking awesome. I didn't do any calculations, but the FOV was definitely more than 60 degrees. It reminded me of an IMAX theater. The greatest part though is that although I could see individual pixels, it was a lot less noticeable than I expected it to be and the experience was so immersive that I didn't really notice.
A problem that I did notice though is that it is blurry on the corners of the display. This is due to the fact that the screen is 4". If it were say a 3" screen, it would have been better, but I didn't mind it that much.
A much bigger problem occured when I tried using both lenses at once with the same display. When there is a single object on the screen, the lenses cause the left eye to see that object shifted to the left and the right eye to see that object shifted to the right. This resulted in unwatchable 2d fullscreen videos, UNLESS I angled the lenses inward towards the screen.
The easiest solution would be to get a 2nd display and center each display on the center of each lens, but due to the size of the screen, that would be impossible because the average distance between the eyes is about 65mm. The solution to the big display problem is to make the two screens angled into a "V" shape.
So after playing around with the lenses, I made a very ugly cardboard cutout to fit the lenses and display into. The final design actually takes advantage of a plastic PSP case that seems perfect for an HMD. I modeled a 3d version of what the final HMD should look like, but it is a WIP.
Here's an exploded view of the HMD modeled in Autodesk Inventor
http://www.youtube.com/watch?v=ETZ8CgVP4nM" onclick="window.open(this.href);return false;
I was initially just going to make this a monoscopic HMD, but then my friend came up with an awesome idea: Use the side-by-side 3d method with videos and games. And it works! The geometry of the lenses happens to work out so that when looking through both lenses, I can see the left image only with my left eye and the right image only with the right eye. I tested this out with some 3d youtube videos and some of the side by side pictures on this site's homepage.
The obvious downside of the side-by-side 3d method is that it cuts the horizontal resolution in half, but it works, so I'm happy.
Here's the big question though: How am I supposed to play PC games in 3d on my phone if its a PHONE? Well, there just so happens to be an app available called Splashtop Remote which is a VNC server of sorts, but with a very high FPS. I say very high RELATIVE to standard VNC programs that run on the phone. The standard ones usually get 1fps. Yes, ONE. Splashtop gets about 15-20, which I know isn't spectacular, but it works. For those who don't know, the app mirrors whatever is visible on the monitor of the computer running the server program. So its basically a remote display.
So I downloaded the iz3d driver and set it to side by side mode, fired up Left 4 Dead, and BAM my homemade HMD was working in stereoscopic 3D.
More pics and videos to arrive soon.
Questions, opinions, etc.? Sorry for such a long post.