Decisions. (Decisions, Decisions)
Decisions have had to be made. I have made them.
The Head Mount & The Optics
I scrapped my View-Master & welders helmet idea and have bought a physically intact, but electronically broken Virtual Research VR4 head mounted display. This really is an historic piece of hardware, one of the origionals. The serial number is ‘Demo 5‘! and the date is 1995. it’s 15 years old and it’s longevity is due to excelent construction. It’s easily disassembled and is, in my opinion, an excellent choice for an upgrade, not just because of it’s physical characteristics, but also because of it’s superb 60 degree field of view optics.
I made my decision following a read of the first post in this thread. Further reading of this post also led me to an excellent video tear down of the kit here. Which in turn led me to a website called V-Rtifacts, run by a very generous and helpful gentleman called Tone. VRtifacts has a little shop of old VR equipment, on sale are working VR4 headsets for $450 – Tone let me have the broken one for $200 – he shipped it the same day and very soon afterwards I had it.
15years old!
The Optics
Apparently, these are the same optics as used in all newer incarnations of this helmet, including the latest VR1280 model! This I am hoping, is because they are very good optics. The cynic in me thinks it might just be because 20 years ago they commissioned the manufacture of a heap load, thinking that VR was going really take off! Boo to cynisism.
The Display System.
Following previous research, I know that I can’t afford a set of dedicated modern displays and controller boards. Nor could I find any old 1.3″ AMLCD kits – which would have been by far the easiest solution!
The original display is the VR4 was a poultry 170, 000 (logical ) pixels. Although Iwant a minimum XGA resolution, at this stage, frankly, I’m gonna have to put up with less!
Technology needs to catch up with my requirements, or, rather, the cost of the technology needs to catchup with my budget. I need to make a 1.3″ (33mm) image, as this is what the optics are calibrated for, I don’t want to have to dismantle anything I buy, as I would want to re-use whatever solution I integrate, or at least, be able to re-sell it – especially considering that the end result could be crap! The other thing, of course, is that if the end result is workable, then, obviously, I will want to re-re-upgrade (once the cost comes down) for a better display.
To this end, I decided that the best bang for buck in the micro display market at this time is found within pico projectors. Well, actually it is found generally within projectors – but these are a little bigger than pico’s and.. if I play my cards right, I should be able to mount pico projectors directly onto the headset with little or no modification.
Just to make sure I bought a couple of old projectors and ripped them apart. I’ll briefly cover that later.
I decided to buy a couple of Samsung SP-H03‘s. This was a difficult choice. The resolution is only WVGA, 854X480, of which I would likely only end up using VGA, 640X480.
Samsung SP-H03
I could, however, buy these quite cheaply; for around £160 each. I really wanted SVGA resolution, as offered in the AAXA Pico 2 and several identical Pico’s, such as the Chinavision Pico Pro. the issue with these was lead time (They all seem to live in China) and their weight, although still very light, the Samsung weighs only a 130 grams without the battery. Also, and importantly, the Samsung doesn’t just use a boring single white LED transmissive AMLCD – it uses a Texas Instruments single chip pico DLP with 3 (count ’em, 1,2,3!) separate LED light sources – this should give it awesome colour and clarity, perhaps even surpassing an SVGA AMLCD equivalent. Certainly, grown up DLP’s generally blow LCD’s out of the water.
The final thing I needed was materials. A project like this is bound to require some bit’s n bobs which I don’t normally have. So I went to Hobby Craft; where the cash was extracted from my wallet through a gaping hole in my chest of bloody disbelief. They must make a decent mark-up there! Anyway, I got myself some acrylic, some modelling board and a glue gun. the other bit’s n pieces I may need will come from the projectors which I mercilessly tore to bits.