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Next-Gen Display: MicroLEDs

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31–40 of 93 posts

Re: Next-Gen Display: MicroLEDs

#31
post #9

I'm not sure I see the "revolutionary" aspect of this. With displays, you don't need to make power consumption arbitrarily small. By Amdahl's law, you only need to make it a small percentage of the cpu (and wireless) consumption. In this respect, Sharp's transflective displays (that were found, for example, in the pebble watches,) were already resolving the power issue in the context of smartwatches.

Firstly, these displays promise brighter colors and a wider gamut.

Secondly, you only get long battery life in a small package one tiny step at a time, and you want them, either to increase battery life or to make smaller watches. The latter is particularly hard. A typical smart watch is around 10 mm thick, nowadays, 2 or so of which are taken by the display and the back panel. So, if you want to make it 8 mm thick, you lose 25% of inner volume and, ballpark, the same on battery volume (taking into account that the battery is shielded, likely closer to 30%)

Finally, I’m not sure that transflective display is that low power if you want to frequently update the display. Looking at the data sheet of https://eu.mouser.com/new/Sharpsma/sharpmemorylcd/, page 14 lists power use of 15 μW on a static display, 50 μW on a display that updates at 1 Hz. Extrapolating, I get 2115 μW at 60 Hz, or about 2 mW. The capacity of a typical smartwatch battery is less than 1 Wh, so that display could display video for 500 hours or 20 days (rounded up a few times)

Re: Next-Gen Display: MicroLEDs

#32

The transparency aspect is so cool! They look like they'd be awesome for AR goggles, although I don't know enough about the optics to know if that'd be feasible. We may also be close to getting those Star Trek style clear displays! Exciting stuff.

I was actually wondering recently if you could do something like that with a small off-the-shelf TFT screen. ILI9341 modules are less than $5 each, and have 16/18-bit color with typical resolutions of 240x320. You can separate the actual panel from its backlights and casing without damaging it if you're careful, so I was thinking of trying to maybe put one in a box for a sort of DIY projector or something. But I'm al…

People have been modding old overhead projectors with LCD screens for as long as universities have been throwing both away (so since early 2000s). Here is a recent example[0]. For some reason nobody seems to realise that you can just place a smarphone underneath it and use that. I mean, the principle is the same as this video[1] :P

I just got myself an abandoned one - the Karolinska Institute, where I work, is moving, and they are throwing away a lot of crap. I took one of the overhead projectors, stripped out the old 240 Watts lamp + cooling unit (to be replaced with a less energy-draining yet brighter LED panel from the inside. Perhaps even one of those that can be programmed to change colors).

[0] https://www.youtube.com/watch?v=gXX2UkucO8w

[1] https://www.youtube.com/watch?v=FKL9_bdtHq0

Re: Next-Gen Display: MicroLEDs

#33

There was a time where I’d get super hyped when reading these kinds of promises. Transparent displays, foldable screens. Truth is, we’ve been seeing working prototypes at events like CES for more than 15 years. I’ve come to realize the mechanics of these companies are similar to the car industry. New technologies are presented for the same reason car companies present strange concept cars: PR

These might be good for pro photographers, though right now I'd rather see affordable 300dpi A4-sized e-book reader with tablet pen and SD card slot to get rid of all my paperwork.

Re: Next-Gen Display: MicroLEDs

#34

The transparency aspect is so cool! They look like they'd be awesome for AR goggles, although I don't know enough about the optics to know if that'd be feasible. We may also be close to getting those Star Trek style clear displays! Exciting stuff.

I was actually wondering recently if you could do something like that with a small off-the-shelf TFT screen. ILI9341 modules are less than $5 each, and have 16/18-bit color with typical resolutions of 240x320. You can separate the actual panel from its backlights and casing without damaging it if you're careful, so I was thinking of trying to maybe put one in a box for a sort of DIY projector or something. But I'm al…

I've built an AR headset with a normal backlit LCD, fresnel lens, and a semi-transparent mirror. Not great but it works.

You can certainly build a DIY projector that way. Building a high quality projector is hard but a crappy one is very simple. If you jam an LCD between a light source and a lens at the right distances you will get an image. Slide projectors, camera lenses, magnifying glass lenses, even those fresnel page magnifier lenses work.

Re: Next-Gen Display: MicroLEDs

#35
post #18

I’m guessing that “photo” is in fact a mock-up? Because it appears to show a screen that is able to occlude the background with both light and dark colors, which is not consistent with the description of the technology.

A reverse image search turns up what appears to be the photo used as the background for the picture in the article, so yes, it seems to be a mockup.

Re: Next-Gen Display: MicroLEDs

#36
post #31
post #9

I'm not sure I see the "revolutionary" aspect of this. With displays, you don't need to make power consumption arbitrarily small. By Amdahl's law, you only need to make it a small percentage of the cpu (and wireless) consumption. In this respect, Sharp's transflective displays (that were found, for example, in the pebble watches,) were already resolving the power issue in the context of smartwatches.

Firstly, these displays promise brighter colors and a wider gamut. Secondly, you only get long battery life in a small package one tiny step at a time, and you want them, either to increase battery life or to make smaller watches. The latter is particularly hard. A typical smart watch is around 10 mm thick, nowadays, 2 or so of which are taken by the display and the back panel. So, if you want to make it 8 mm thick,…

Wider gamut is what might be the differentiator here.

With respect to power consumption, the video codec would probably draw more than 100mW [1], and at that point, the 2mW display consumption would not matter.

[1] a 640x480@15fps hardware decoder draws 71mW. https://cseweb.ucsd.edu/classes/fa11/cse291-a/pdf/02/JSSC_st...

Re: Next-Gen Display: MicroLEDs

#37
post #19

I hope they start with small array counts and build up from there.. you can imagine them having a "super bright super low power small display with 200x400 pixels" actually being useful in plenty of places.. then build up from there step by step.. So if AR is that application then, great. But don't try to jump from barely manufacturable to 4k2k VR display as your first step.. sort of like Lytro -- they just were like,…

> My advice to the microLED people.. start small..

To your point, reports are that Apple is starting with Apple Watch.

Re: Next-Gen Display: MicroLEDs

#38
post #8
post #7

Earlier quoted context omitted.

It won't be on your phone by 2020. It is not clear whether it will ever be on your phone. The iphone 8 has about 3 million subpixels which will all have to be individually cut, tested and assembled on a display for a microled to work. Or, alternatively, the display can be made from a whole wafer, which will cost about a thousand dollars for the raw materials and perhaps $5k for the finished display. I know technology…

It already works: https://www.forbes.com/sites/johnarcher/2018/01/11/samsungs-...

At 146 inches of screen. With very visible pixels when up close.

Now get that to 300-400 dpi in the palm of your hand. That's the issue with getting it "working" in a phone. Quite different.

Re: Next-Gen Display: MicroLEDs

#39
post #25

Earlier quoted context omitted.

Dream on, they’ll make it thinner

They might. But over the last 3 generations they made them thicker and about tripled the battery life.

If I remember rightly the thickness increase was mostly the sensors too.

Re: Next-Gen Display: MicroLEDs

#40
post #26

There was a time where I’d get super hyped when reading these kinds of promises. Transparent displays, foldable screens. Truth is, we’ve been seeing working prototypes at events like CES for more than 15 years. I’ve come to realize the mechanics of these companies are similar to the car industry. New technologies are presented for the same reason car companies present strange concept cars: PR

The weird thing is that we already have “foldable screens.” But all the phone makers have done with them is to give us slightly less bezel on our glass rectangles. I’m wondering if this is a “flying car” thing—if actually handing consumers ultra-thin bendable (but not actually creasable ) panels would be a dumb idea, because consumers would try to exceed their tolerances and break them too easily. (This is also, I th…

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