Fredz wrote:You can find 3" diagonal displays with reasonable resolutions in cameras, if 3" is too big I guess lower size displays could also be found. For example the Nikon Coolpix P7000 incorporates a 3" TFT display of 921,000 dots (most certainly 1280x720) and it can be found for $299 online. Also maybe a design for 3,5" displays can be created considering this size is used in some cell phones (iPhones for example). After all one of the first HMD (VIVED in 1985) was based on commodity hardware like this, using Watchman TVs from Sony at the time.
What do you mean by overlap exactly ? I don't really visualize how it would work.
921,000 dots is not much at all, certainly not 720p. That is counting all the subpixels! 640x480x3=921,600 dots (That is how Vuzix named the VR920, it had about 920,000 dots). So unfortunately, that 3" display in the P7000 is the same/lower res than you can get from the PR3.
Even if it was higher resolution, we still have no way to drive the panel.
And yes, a design for 3.5" panels could be made, but we would need to have drivers that support adjustable overlap. The picture you made is somewhere correct, but you made a mistake: See how you made the squares a lot bigger in the image with overlap? Don't do that! If you make them the same size, you will see that you get a lot of extra space on the far right of the right display, and the far left of the left display; This lets you use panels that are too wide to place directly in front of each eye, and also greatly expands horizontal FOV.
@ERP: iPhone 4 retina displays, why not. But like you said, driving them is hard. My background with displays/control boards actually far predates my work with HMDs, and I gotta tell you, it would be next to impossible to use iPhone 4 displays.
These displays are made to be driven directly from SOC (System-on-a-chip) units that are used as the basis for most embedded devices, and these devices have digital video outputs designed specifically for those kind of displays. A matched pair.
Now, if you could have a custom ADC (Analog to digital converter) microchip designed to drive them, then you are all set! Problem is, that costs tens/hundreds of thousands of dollars if you are not using a panel that has a common drive format (Like LVDS), and the panels used in these phones are of the former category.
Now, you could make a one-off control board to drive these panels using an FPGA (Field-programmable-gate-array), they are commonly used for prototyping things like video control boards. Problem is... You would have to reverse engineer the display (Proprietary cell phone displays are not very well documented, generally), and then configure the FPGA to drive it from scratch. On top of that, FPGAs are bulky and expensive ($,$$$+), especially ones that are powerful enough to drive high resolution panels. You can find some work where people used FPGAs to drive older iPod displays, the 320x240 ones, but doing the same with a retina display is an order of magnitude harder.
It is just a really, really tough problem. Sure, we could demonstrate what is "viable", but spending hundreds/thousands of dollars on something that only works with a limited software demo is not really worth it.
It is really rather depressing.
The Wide5 uses an FPGA to do its video processing (So you have less strain on the computer), and that one costs thousands of dollars. Unless you made an ASIC that functioned the same way, every single Wide5 needs one of those FPGAs, and nice ones like that are $,$$$ at a minimum.
