Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

A 60 GHz phased array for $10

hscott.net

Post reply on HN
Print view View original

51–60 of 111 posts

Re: A 60 GHz phased array for $10

#51

Post by lachlan-sneff »

hwillis wrote: post #43
jobseeker990 wrote: post #22

Earlier quoted context omitted.

Have any further reading I can do on this?

https://www.spar3d.com/news/lidar/mits-10-lidar-chip-will-ch... holographic displays would use eye trackers to show each eye a different image. Solid state zoom is maybe a bit of a stretch, but it would involve pixels becoming sensitive to angles more inward or outward from the sensor's center.

I'm not an expert, but I believe that's not how holographic displays would work with optical phased arrays. I believe a phased array can make it seem that light is being emitted from any point above the display (within the display angle of the opposite side of the display). There's no need to track observers, because it would be an honest reconstruction of the light emitted from a real 3d dimensional object.

Re: A 60 GHz phased array for $10

#52

Post by philosopher1234 »

ChickeNES wrote: post #28
Traster wrote: post #15

>Now the bad news: SiBeam was bought by Lattice Semiconductor, and right before I gave this talk, Lattice shut down the entire SiBeam organization and ended support and production of this part. I didn’t find out about this until months later, when I contacted the sales engineers I had been talking to about this part and they told me what happened. This is one thing that really pisses me off. Time and time again you'v…

>yet the second the sale is closed 90% of the things that the company did that made it valuable are jettisoned If it were valuable they wouldn't be jettisoned

Unless gasp people can make mistakes

Re: A 60 GHz phased array for $10

#53

Post by AYBABTME »

nathancahill wrote: post #29
sp332 wrote: post #17

Earlier quoted context omitted.

In 2014, Michael Abrash gave a talk summarizing what's needed for a feeling of presence in VR. He said 20 ms motion-to-photon latency is required for the virtual world to feel like it's "nailed in place". So 5 ms is 25% of the latency budget.

The number I've heard, don't ask me from where, is 16 ms.

That's framerate (how often images need to be rendered) at 60hz. Latency is separate from that: you can have a 60hz framerate with 24h latency if you watch a video you recorded yesterday.

In the parent's case, 20ms latency from movement to visible motion is part of the pipeline that:

- reads input

- evaluates solution

- returns solution to your screen

All kinds of things add to this latency: polling frequency of your input device, bus speed of the device, how fast you can update the world, how fast you can render the update, how quickly that updated image can be sent to the screen, how quickly the screen is able to turn this into visible light. etc.

Re: A 60 GHz phased array for $10

#54

Post by colechristensen »

TomMarius wrote: post #27
colechristensen wrote: post #19

Earlier quoted context omitted.

Some companies are purchased only so they won't become major competitors.

Companies are not primarily purchased, but sold. The previous owner could've continued, but they've chosen not to. We can't dictate them what to do, right?

The people selling (or at least that have any say in making the sale) and the people doing are more or less always different sets of people.

It is not a matter of a blacksmith hanging up their hammer but boardrooms playing wealth games. I wouldn't shed any tears for restrictions and obligations on the actions put on the latter.

Re: A 60 GHz phased array for $10

#55

Post by ani-ani »

jobseeker990 wrote: post #22
lachlan-sneff wrote: post #18

Phased arrays are very cool tech. Personally, I can't wait for visible-wavelength optical phased arrays to hit the mainstream (they're just now being implemented), since they'd enable tech like legitimately holographic displays and video cameras with digitally programmable optical zoom.

Have any further reading I can do on this?

This chapter by Brian Wowk is a good start. It explains the basics and compares optical phase arrays against holography (that poor word, keeps getting abused!):

https://www.phased-array.com/1996-Book-Chapter.html

Re: A 60 GHz phased array for $10

#56

Post by hug »

nicoburns wrote: post #50
bordercases wrote: post #47

Earlier quoted context omitted.

Then how do we realign capital to stop keeping large loss-running companies or now slow-growing companies on life support so that basic innovations can still penetrate the market? IIRC Zuckerberg had the option to relinquish control of his company but other than taking that sweet sweet In-Q-Tel dollar still did his best to stay at the helm.

Agressively tax large organisations. There'd be a cost to that, but as this comment chain is discussing, there's also a cost to leaving them with the money and allowing them to use it to stifle innovation.

Aggressive taxation is a prisoner's dilemma involving every government in the world.

Good luck solving that problem. (Honestly, I wish good luck to anyone trying to solve it. Corporate tax is fucked.)

Re: A 60 GHz phased array for $10

#57

Post by vlovich123 »

sp332 wrote: post #17
londons_explore wrote: post #11

Earlier quoted context omitted.

5ms isn't yet at nausea levels though...

In 2014, Michael Abrash gave a talk summarizing what's needed for a feeling of presence in VR. He said 20 ms motion-to-photon latency is required for the virtual world to feel like it's "nailed in place". So 5 ms is 25% of the latency budget.

Not all motion-to-photon latency is created equal.

EDIT: To clarify what I meant, HMDs typically use techniques like ATW/ASW/etc (link posted by Rebelgecko) to do just-in-time correction of the rendered image. The end-to-end motion-to-photon latency of the entire pipeline grows but the part that generates "sick" is very short.

Re: A 60 GHz phased array for $10

#58

Post by m463 »

jobseeker990 wrote: post #22
lachlan-sneff wrote: post #18

Phased arrays are very cool tech. Personally, I can't wait for visible-wavelength optical phased arrays to hit the mainstream (they're just now being implemented), since they'd enable tech like legitimately holographic displays and video cameras with digitally programmable optical zoom.

Have any further reading I can do on this?

not really phased array, but https://en.wikipedia.org/wiki/Lytro

Re: A 60 GHz phased array for $10

#60

Post by bsder »

nicoburns wrote: post #50
bordercases wrote: post #47

Earlier quoted context omitted.

Then how do we realign capital to stop keeping large loss-running companies or now slow-growing companies on life support so that basic innovations can still penetrate the market? IIRC Zuckerberg had the option to relinquish control of his company but other than taking that sweet sweet In-Q-Tel dollar still did his best to stay at the helm.

Agressively tax large organisations. There'd be a cost to that, but as this comment chain is discussing, there's also a cost to leaving them with the money and allowing them to use it to stifle innovation.

I would instead move toward "aggressively tax passive investment above some limit."

The issue isn't large amounts of money. The issue is large amounts of idle money.

Post reply on HN