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MEMS Array Chip Can Project Video the Size of a Grain of Sand(spectrum.ieee.org)

86 points by bookofjoe 1 day ago | hide | 43 comments

This reminds me of the original patents that Magic Leap had, which involved pumping light through a single optical fiber that was wiggled by piezoelectrics into a spiral to project light (https://kguttag.com/2018/01/06/magic-leap-fiber-scanning-dis...).

Seems what it is, but with a "waveguide" instead of an "optical fiber" wiggling about. Seems like a sneaky use of the word "projection" though, since the "surface" the image is "projected" is just what the flopping waveguide head traces, with no projection extending beyond the end of the waveguide.

Yes but one could argue the frame refresh/redraw cycle of a laser projector or lcd projector is the same at slow speed. It’s not just one giant ball of light. It goes through a process and the frame itself has to redraw.

Sure, the image doesn't come from nowhere. In this case, it's a wiggly piezo pushed raster scan with the light source varied to, ideally, match the frame contents for any raster position.

But the "projection" is only to the end of the waveguide, which makes a real image, which could then be protected onto a real surface. It would be as misleading as saying a CRT screen projects an image. Well, not really. A CRT screen uses electron beam projection in the image generation. After that image is generated, it can then be projected.

A scanning beam laser projector can, by all definitions (including that pesky dictionary), project an image as part of the generation. An LCD, a CRT, and this, cannot project an image without additional projection optics attached to it to throw that generated real image.

I understand what they did (very neat), I'm just complaining about the press release wording. And then there's this shoved at the bottom "Because the chip can project so many more spots in any given time interval than any previous beam scanners, it could also be used to control many more qubits in quantum computers". Might as well throw "AI" in there. Or, maybe I'm just confused about it all because I stupidly read a university backed press release.

I wonder if this has implications for custom home chips/prototyping. I'm sure a big issue is vibrations but something like this could remove the need for masks at least. (again, not my area so I am clobbering terminology I am sure). It may open up home fab capabilities.

In general, hobby photo-lithography projects already use DMD/DLP projectors, and some inexpensive optics.

Huygens Optics:

https://www.youtube.com/watch?v=_w0Z2Y5vaAQ

Sam Zeloof:

https://www.youtube.com/watch?v=Nxz_ENnmgtI

In general, getting vanity silicon made is usually much less expensive than trying to bootstrap a fab line. =3

I think half the fun for people that do things like this is figuring out how to out innovate a multi-billion dollar company so that they can make something 1/4th as good but at 1/10000th the price. I bet there are some -really- innovative people out there that would figure alternatives to a lot of the expensive parts of the process and figure out how to be able to produce 2000's level chips at home. I'm not one of them though :)

The problem is that they aren't (yet) 1/4th as good for 1/10000th of the price. Patterning is just one part of the process - and not nearly the most difficult one.

I think abusing a write-off electron microscope to side step the need for masks is also an interesting idea, however, I believe acquiring wafers of sufficient quality and depositing layers to be etched could be the bigger challenge here.

Hold on, if I had an electron microscope, can I just put in a decapped cheap large format photodiode under it, jack the beam current way up, and start etching trenches on it?

I don't think so: it's a microscope, not a synchrotron. :D

I meant "drawing" on a photoresist layer with a SEM and then wet-etching it. Also all silicon in a photodiode is doped, so the etched parts would be of little use, I believe.

And the clean environment as a whole. That's a massive investment and there are a million ways to mess that up.

> however, I believe acquiring wafers of sufficient quality and depositing layers to be etched could be the bigger challenge here

Definitely hard for a home fab but how about a community fab? Not necessarily a geographic community.

for making research grade devices you barely need a cleanroom

wafers are the easy bit.

What is this, a movie theater for ants?

It has to be at least 3 times bigger than this!

or AR glasses?

We can finally say yes to this question

> The chip projected a roughly 125-micrometer image of the Mona Lisa.

This may seem small (barely visible as a dot to the naked eye), but that's also the geometric mean of the Planck length and the diameter of the observable universe. So average size actually.

I really can't follow your comment and I've been trying. Would you mind a longer explanation of what you're getting at here?

They mean 125um = sqrt(a*b), where a is the Planck length* and b the size of the observable universe (I didn't verify). Implying, 125um is some sort of middle ground. *Often said to be the smallest length with physical meaning.

Ok, so it's a bullshit comment. Thank you. You could say this about everything that is not 'Planck length', it's about as useful as Douglas Adams' 'the universe is empty' (only he had a sense of humor).

Oh, even worse they are repeating it in different threads.

https://news.ycombinator.com/item?id=47749957

Why are you so upset by this?

I'm upset at lots of things. For instance that you are still on this website after posting this:

https://news.ycombinator.com/item?id=47743276

But then again, we get anti Islam posts by prominent HN'ers as well so I guess that evens things out.

By your own logic, shouldn’t you be banned from this site for your comments targeting the MAGA nutjobs? https://news.ycombinator.com/item?id=46538172

Why would criticising people for their religious-adjacent views be worse than criticising people for their political views?

I’m sure you’d find your own comment reprehensible if you replaced “MAGA” with “Jewish”. But why? Both are just groups of people who choose to believe in certain things.

Because some of these are clear choices, others are not.

You can be critical of Israel and I'm fine with that - and I'm plenty critical of Israel myself. But to say 'Most Jews are lunatics' is absolutely beyond the pale.

You could say this in more general terms about all people that are religious but you didn't do that and FYI Jews don't generally have a choice about their Jewishness, just like you don't have any choice about which family you were born into.

You could even make the case that most religious people had no choice in their adoption of that religion, but most people have the theoretical option of letting go of their religion if they so desire, but you can not stop being a Jew. This little detail was baked into the religion and it is a serious problem for those that are Jewish and that wish to get away from it - and these people really do exist -, but they can not change their identity to a degree that they themselves would recognize as sufficient, besides, their environment usually also does not recognize it.

In the interest of furthering your knowledge about this:

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

and

https://brill.com/display/book/edcoll/9789004331471/BP000006...

I get all this is complicated, and maybe you really can't follow this in which case my apologies but there is a significant choice between who you work for (say, Palantir, Facebook, OpenAI or Twitter) vs what family you are born into.

As for political beliefs: yes, I'm critical of those that carry water for Trump, Putin, Netanyahu and their cronies, they're out to destroy the world as we know it and if you help enable that you are imnsho part of the problem.

> But to say 'Most Jews are lunatics' is absolutely beyond the pale.

The misquote here does not feel accidental.

I said:

> We’re not allowed to criticise Israel because most jews are lunatics that consider such criticism an antisemitic attack on their person

If “Most Jews consider criticism of Israel to be an attack on their person” is true, then it certainly follows that “Most Jews are lunatics”.

> You could even make the case that most religious people had no choice in their adoption of that religion, but most people have the theoretical option of letting go of their religion if they so desire, but you can not stop being a Jew

Yes, I am aware that some people choose to believe this. However, outside of a specific religious community people will generally not consider you to be a Jew unless you identify as such.

I personally am not religious and therefore don’t subscribe to the belief that people can’t stop being Jews.

Sure!

It was a joke :)

Seems like you could put a few of these on a contact lens and minimally get a small private HUD. Seems like with a few of them (or fast enough scanning speed) you could build effectively a light field to give it depth)

This might be relevant for Augmented Reality headgear.

Happy days at the ant colony.

How do you even fit a video projector onto something that small, the physics feel like they shouldn't cooperate.

Sounds like this will have interesting fiber-optic implications?

This is actually getting close enough to manipulate the _phase_ of light! And doing that would allow creating true holograms.

Or alternative true augmented reality glasses that are not limited to one focal plane.

Have I got news for you:

https://www.rp-photonics.com/phase_modulators.html

Except that you need that for individual pixels.

Electro-optic modulators already exist — still no StarTrek. :(

Oh wait. It does have the correct title. My fruit flies are cheering.

Cool. Now I can show videos to my fruit flies! /s

Srsly title should be "MEMS Array Chip the Size of a Grain of Sand Can Project Video"

not

"MEMS Array Chip Can Project Video the Size of a Grain of Sand"

It is actually about a 0.125mm projection, not the size of the chip. But more about steering lasers, which is really what they wanted to do.

This is revolutionary. No other way to put it.

It certainly looks like something that will find novel applications.