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Comment by doublerebel | Hacker News Reader

It looks like the acquired startup, Akonia, uses waveguides like Hololens but uses photopolymer in place of the diffraction grating.

https://mspoweruser.com/akonia-plans-holographic-waveguide-e...

https://venturebeat.com/2016/12/26/akonia-uses-holography-to...

Whitepaper on the photopolymer: https://www.ncbi.nlm.nih.gov/m/pubmed/25835673/

They were going to replace tape storage with holographic storage before they figured out how to apply it to AR. Here's the holographic storage pitch deck:

https://science.energy.gov/~/media/np/pdf/sbir%2520sttr/SBIR...

http://www.pdsw.org/pdsw15/slides/AkoniaHolographicsKeynote....

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Akonia/Apple: 60° FOV (targeted)

Hololens: 35° FOV (currently)

Magic Leap: 40° FOV horizontal / 30° vertical (currently)

Humans: 210° FOV (for reference)

https://en.wikipedia.org/wiki/Field_of_view

Consider foveation as well — only a small part of that is truly in “focus”.

Some up and coming be glasses take this into account and expend lesser resources on the part that’s outside the important part (they don’t render that part in a high resolution, so it’s left blurry, which is actually how our eyes work anyway)

That only really works when combined with low-latency eye tracking. Yes, whatever we don't look directly at is really blurry, but our eyes move.

On the other hand, eye tracking is just about ready already. I've heard Google is working on a VR system using foveated rendering with tracking.

It's already implemented in the StarVR headset (which has 210° FOV) using Tobii eye tracking tech. They had a working demo at Siggraph a couple weeks ago.

It’s crazy unbelievable how low-latency Tobii’s eye tracking is

Even their consumer grade 4c is extremely impressive. It has neat uses for simple desktop usage. For the handicapped folks it’s an absolute boon

> It’s crazy unbelievable how low-latency Tobii’s eye tracking is

Tobii uses cameras at 60 or 120 Hz, so >8 ms. It's the mature but old and limited tech. MEMS-based tracking is faster. During a saccade, you've the samples to predict where the eye is going to end up fixated, 20 ms before it happens.[1]

GGP> but our eyes move.

Slowwwwwlllyyyy. ;)

[1] https://www.youtube.com/watch?v=uUAxVhZQs-o

> Consider foveation as well — only a small part of that is truly in “focus”.

Here's an optical illusion which illustrates how surprisingly tiny your fovea's FOV is: https://www.shadertoy.com/view/4dsXzM .

Not important. Rendering performance is not what limits the FOV. It’s the display technology.

Out of interest, what's the FOV for people who normally wear glasses?

Interesting question, but I'm not sure how relevant that is. Try covering the parts of your view beyond the edges of your glasses, e.g. with your hands, and see if the experience is the same as with just your glasses. I bet there is a huge difference.

I think the issue is that the parts outside your glasses are blurry anyway (even for people with perfect vision), but even the blurry part is important for the experience.

"I bet there is a huge difference."

Not sure there is for me - if I blank off the area outside my glasses things really don't look that different - but I am quite shortsighted... :-)

I’m quite near sighted as well but being able to see light and motion (even if blurry) is important to me even if it’s only really beneficial mentally. I might be blind but I don’t want to feel blinded.

From glancing at the edges of my glasses, about 160-180 degrees, but anything close to the edges is always blurry; there's no way to avoid some level of lensing error. (Barring contacts.)

I've always favored extra-wide glasses, though. Some of the smaller ones might be 140 or even 120 degrees.

Aryzon - 110° FOV.

Do you have a source for that? Their website says it has a FOV of 35° x 20°.

When I configure FOV in "Sites in VR", I can see 110°. Maybe I'm wrong, because I have no other gadget to compare.

Thanks for the details. I briefly looked at holographic storage when I did my undergrad thesis on holography.

Anyone care to comment as to whether this storage methodology could be moved forward?

(Apple acquisitions are always fascinating. I did a deck on PrimeSense for an old boss when we thought it was going into an Apple TV product rather than FaceID.)

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