Woot! Lenses just arrived at the office and of course I had to take em out to experiment with.
First things first - I DO stand corrected... I now believe that Fresnels CAN produce a sharp, quality image in an HMD!
I honestly had my reservations when I ordered these because of the experience I've had in the past w/ Fresnel lenses. Generally the ones I've worked with offered not much more than a muddy, washed-out view. I'm happy to say these are the exact opposite!
I'd even go as far as to say that when looking through ONE of them at my monitor (positioned ~120mm FL, Fresnel grooves towards the screen)... I can absolutely not tell that I'm looking through a Fresnel vs any other decent quality large acrylic optic. There's no perception of the Fresnel grooves, etc. at all!
Now, upon adding the second lens things do degrade just a bit. A bit of contrast is lost, a tiny bit of lens smear is detectible on high-contrast scenes, and all of the applicable aberrations are more prevalent. However, much of this is to be expected w/ any type of uncorrected lens assembly.
Also I would like to point out (as Palmer, GeekMaster and others on this thread already have) that Fresnels are are by no means a magic bullet and you will still have to work within the same constraints that apply to standard plano convex lenses. Ex: You still have spherical, chromatic, field curvature, etc. taking shots at your view so you'll have to do your best to compensate as usual.
With all that said I'm still 100% confident that these lenses do offer some excellent advantages for HMD design where immersive FOV is the primary goal.
-Huge immediate-FOV combined with a very generous eye-relief.
-Full eyeglass compatibility do to that eye-relief.
-Huge reduction in weight vs a comparable system using standard lenses
-Huge reduction in cost vs a comparable system using standard lenses
So, all in all I'd say the lenses are a definite win.
Of course now I've just got to find the time to actually build one of foisi's InfinitEyes and see how it all performs together. My guess is it should be a pretty excellent experience.
My Current VR Setup
- N-Vision Datavisor 80 HMD (1280x1024, 80 FOV at 100% Overlap)
- Ascension Technology Flock of Birds 6DOF Magnetic Tracking + Extended Range Transmitter
- Prototype HMD (~100 FOV) - Specs and design to be shared after patent issued.
- IZ3D for non stereo-ready apps
- GlovePie for TrackIR emulation for apps without native Ascension Tech FOB Support
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