LPD: Laser Phosphor Display - Successor to CRT?

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thatoneguy
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Re: LPD: Laser Phosphor Display - Successor to CRT?

Post by thatoneguy » 22 Oct 2020, 18:37

Chief Blur Buster wrote:
16 Oct 2020, 14:41
Everyone has preferences on their preferred artifacts -- witness CRT and plasma users holding onto displays. Displays are inherently pick-your-poison. Dislike ghosting/coronas? Dislike flicker? Dislike display motion blur? Dislike phosphor trails? Etc.

Some laser phosphor projectors have its place, though it is a niche purpose.
By nobody I mean the mainstream manufacturers don't want them because of their inherent disadvantages. CRT's for example look washed out in a bright room and the black levels suffered too because the phosphor absorbs incoming light(or smth like that not sure on the specifics), so did Plasma displays.

Yeah not denying they have their place but not on the consumer space.
ChaosCloud wrote:
16 Oct 2020, 20:43

IMO the worst thing about phosphor is that contrast suffers in a lit room, since the phosphor coating is not truly black.
Yup. I don't think it has to do with phosphor coating though, I think I read something once about how phosphor absorbs ambient light or something like that.
ChaosCloud wrote:
16 Oct 2020, 20:43

I don't know about the Celluon, but I actually have tested the MP-CL1. Resolution is approaching 720p, but it's hard to say without sharply defined pixels or scanlines.
Pics here compared with a 1080p LCD.
https://www.avsforum.com/threads/sony-m ... t-44716993
Celluon used Sony's engine so it's basically the same thing. Sony added some improvements like keystone adjustments and some other features iirc.
The pictures you linked to look very soft, doesn't even look remotely close to 720p, it doesn't look sharp at all. Really bad focus, looks blurrier than a lot of old consumer CRT's even.
It really looks as blurry as an upscale. Heck it's probably doing uspcaling from 360p to 720.

Another problem with it is that it's super dark and basically unusable in anything but a pitch black room.
Laser Beam Scanning is extremely niche and unfeasible. It's a wonder why Microsoft experimented with it for their Hololens but then again Microsoft does a lot of dumb shit.

thatoneguy
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Re: LPD: Laser Phosphor Display - Successor to CRT?

Post by thatoneguy » 22 Oct 2020, 19:15

ChaosCloud wrote:
18 Oct 2020, 20:13
MicroLED does not seem to have a cost-effective method of production (at least for consumer format displays), and OLED, while now being produced, is still quite vulnerable to burn-in. The brighter the pixels are run, the faster they burn-in, and to have a line-by-line scan similar to CRT would require extreme brightness for that line of pixels. MicroLED may have the same vulnerability as well.

I see LPD as a potential stopgap solution. >120Hz with single pass scanning would be a marked improvement over what current LCDs are capable of.
AFAIK LPD is only Prysm's thing whereas MicroLED is in R&D by many companies and has had countless investments into it.
You're much more likely to see MicroLED in the consumer market than LPD.

MicroLED doesn't have burn-in like OLED does because it's inorganic. Driving the pixels harder is going to shorten lifespan but not necessarily cause burn-in.
A CRT's phosphor typically shines at around 5000 nits or so for a brief period iirc(electron gun itself is much higher than that) so technically it will be very doable on a MicroLED display and might come sooner than you think(although technically we'd need a little bit more than that for retro games to make up for that brightness loss that occurs when you use CRT Shaders :P )

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Re: LPD: Laser Phosphor Display - Successor to CRT?

Post by Chief Blur Buster » 22 Oct 2020, 21:15

thatoneguy wrote:
22 Oct 2020, 19:15
MicroLED doesn't have burn-in like OLED does because it's inorganic. Driving the pixels harder is going to shorten lifespan but not necessarily cause burn-in.
Also, some niggly elements such as the Talbot-Plateau law is less of a barrier with LCD (outsourced light) than OLED (tiny pixels).

The Talbot-Plateau theorem is the reason why the 10,000 nit display that I saw, is an LCD display, not an OLED display. That's also delicious nit headroom that could keep strobed HDR (e.g. 1000 nits at 1/10th persistence).

Like, say, a LED-based projector bulb lighting up a LCD panel. Technically, they can be strobed without much brightness loss, especially if you shrink screen size (to too bright nonstrobed, will look amazing strobed). Too bad they didn't build many strobed LCD projectors. The brightness of LCD is almost unbounded, right up to the ability of the LCD to absorb heat from excess light -- which is far higher.

It's noticeable in virtual reality. The Valve Index LCD VR headset can do 0.3ms MPRT, while the Oculus Rift CV1 OLED VR headset can do 2ms MPRT. This is a great example of the Talbot-Plateau theorem in operation helping strobed LCD get less motion blur than strobed OLED.

That said, they have tested 2-million-nit MicroLED microdisplays already, and in those, the screen is the projector bulb. It's impressive how bright direct-view MicroLED can be, though at those brightness, they definitely begin to burn in (CRT-style burn in) similar to a very old, worn jumbotron that looks speckly. In that sense, burn-in can still happen to overdriven ultra-bright MicroLEDs. Just a lot more burn-in insensitive.
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ChaosCloud
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Re: LPD: Laser Phosphor Display - Successor to CRT?

Post by ChaosCloud » 22 Oct 2020, 22:24

blurfreeCRTGimp wrote:
20 Oct 2020, 13:33
If you had a MEMS laser doing raster style scan out, and you used quantum dot pixels on the face of the glass as opposed to a traditional phosphor wouldn't you get the best of all possible worlds?

Motion resolution

Variable resolution inputs as opposed to fixed pixel

infinite contrast

great color without burn in?
Did some research and it seems like Quantum Dot would work quite well for this application.

It would be excited by UV or blue laser to produce very deep and pure primaries for wide colour gamut.

As far as I can tell QD is impervious to burn-in.

Has basically instantaneous response time whereas phosphor takes some milliseconds to reach full brightness and then some tens of ms to decay, a cause of motion artifacts.

In comparison to straight RGB laser scanning I suspect it would be better able to achieve greyscale as well as dark tones.

I think there is a lot of potential here. Was looking for but did not find any reference on interaction between QD materials and laser. Curious what brightness the current-gen QD material can achieve.

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Re: LPD: Laser Phosphor Display - Successor to CRT?

Post by blurfreeCRTGimp » 23 Oct 2020, 01:19

So, if this is the case why in the hell are we chasing mini LED, OLED, and other displays that have so much blur? Imagine how much more utility our GPUs would have if you could drive games at just 60hz and with lower resolutions?

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Re: LPD: Laser Phosphor Display - Successor to CRT?

Post by Chief Blur Buster » 23 Oct 2020, 05:47

blurfreeCRTGimp wrote:
23 Oct 2020, 01:19
So, if this is the case why in the hell are we chasing mini LED, OLED, and other displays that have so much blur? Imagine how much more utility our GPUs would have if you could drive games at just 60hz and with lower resolutions?
The Talbot-Plateau law only applies to strobing.
This is not a problem for strobeless blur reduction (brute framerates on brute Hz)

MiniLED and OLED can be very fast. They will have no problems doing strobeless blur reduction (1000fps 1000Hz). Their incredibly fast GtG makes frametimes nearly perfectly linear to motion blur; so doubling Hz reliably halves display motion blur on OLED, MiniLED, and MicroLED.

Strobeless blur reduction (via sheer brute framerate & Hz) is full brightness since it doesn't require flicker/flashing/BFI

CRT clarity via flickerless method (low persistence sample-and-hold) requires really brute framerates & brute refreshrates on a fast-GtG display. GtG needs to be a tiny fraction of a refresh cycle to allow frametimes to scale linearly with motion blur (half frametime = half blur), since GtG retards the Blur Busters Law MPRT(100%) linearity.

1ms of frametime = 1 pixel of motionblur per 1000 pixels/sec

If you want to simulate the virtually zero blur of a 0.5ms phosphor CRT, but doing it in a FlickerFree display (no phosphor, no BFI, no strobe, no ULMB, no PWM)... Then you will need 2000fps at 2000Hz to accurately simulate 0.5ms CRT phosphor in a steady-state continuously-illuminated display (aka Sample and Hold). The great news is that GtG of OLED/MiniLED/MicroLED is much faster than 0.5ms real-world GtG, which is just exactly what we need for good strobeless blur reduction.

OLED/MiniLED/MicroLED follows Blur Busters Law to a tee, as they're the displays that are closest in resembling the ideal GtG=0ms. They accurately follow photograph blur equivalency. They accurately linearly scale MPRT(100%) and Blur Busters Law almost perfectly as a result.

Image

Image

Now that said; LCD is definitely still a horse in the 1000Hz race.

Real world GtG will have to become far faster to reliably do 1000fps 1000Hz. But blue-phase LCDs can have microsecond GtG pixel response, and technically could be a potential candidate display technology down the road (if contrast ratios are improved sufficiently enough), especially combined with high-density FALD MiniLED backlights to get OLED-quality blacks with less blooming than CRT phosphor.

Different engineering challenges for the two different methods of motion blur reduction. But if you can't wait, then you might also want to read CRT Nirvana Guide For Disappointed CRT-to-LCD Upgraders. There are tricks avaialble.
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blurfreeCRTGimp
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Re: LPD: Laser Phosphor Display - Successor to CRT?

Post by blurfreeCRTGimp » 23 Oct 2020, 16:53

My issue is, your own writings about going blur free with brute force seem impractical, even with the great advancements you speak of.

2,000 FPS at 2,000hz to have emulation of a .5ms of phosphor decay time? Even if you have the best machine learning based FRAT, you can get usually at most double the FPS without too much quality impact.

A 3090 on the next gen AMD CPUs will probably top out at 400 native FPS (to be optimistic and generous) in ridiculously well optimized games with something like DLSS.

So, if you used FRAT you could potentially get 800HZ with synthetic frames without BFI.

While awesome, that would be an insanely expensive rig, affordable to very few to get you not even half way to your goal by brute force.

I already have a BenQ XL2720 144hz overclocked to 170hz running on my 1060 3gb.

Compared to my crappy little 20 year old $200 Sharp 14 inch Standard Definition CRT, the image is dark and looks like ass. The strobe backlight is also already failing in places. I don't say any of this with joy by the way, lol. The little TV also has color comparable to an OLED.

A MEMS display with Quantum dots vs phosphors could get us so much closer to blur free without all these hacks, drawbacks, and synthetic simulation. It would be more affordable scaled up, (in terms of the overall hardware cost.)

Considering that it also wouldn't need to be fixed pixel, current displays, even the newest are just disheartening.

The video that Linus just did about the $1500 48 inch LG CX illustrated the issue well. That OLED murdered the also expensive 360hz LCD in clarity, but has severe burn in issues, is sample and hold, requires native resolution to look its best, and costs $1500. Not too mention the insane rig you need to run it at 120hz.

It seems as though with flat panels, we are designing everything around their flaws, and trying our best to mask them, while ignoring better ways to draw an image to a screen.

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Re: LPD: Laser Phosphor Display - Successor to CRT?

Post by Futuretech » 24 Oct 2020, 01:29

blurfreeCRTGimp wrote:
23 Oct 2020, 16:53
It seems as though with flat panels, we are designing everything around their flaws, and trying our best to mask them, while ignoring better ways to draw an image to a screen.
A few years ago circa 2013/2014 era. The former [H]ardOCP now hardforum as [H]OCP ceased to exist with Kyle shutting down the main site and leaving the forums.

Funny enough someone said the perfect comment about LCD technologies this was prominent when the first 120Hz LCDs were popping in and a few 4K monitors as well sliding in.

LCD = the communism of technology. No matter how many times we kill it, it doesn't want to die.

The sheer fact is I still see LCD technologies still available even to the next century in 2100. Funny enough the smaller you make LCDs the better they become. Obviously why LCD Smartphones look better than larger screens. The larger you scale the LCD the more issues occur.

Really like the communism comment of LCD. It's not gonna go away and even if there are other better solutions I would NOT be shocked if some 1980s/1990s LCD manufacturing machines modified and retooled with 2000s technology still exist. It would NOT shock me in any way, shape, or form if even first Gen. LCD manufacturing machines retooled to newer stuff still exist in some nations.

I agree with everything you say member: blurfreeCRTGimp about better technologies available I don't even game anymore and I'd like to upgrade my 1920x1200p display to a better, superior, newer technology monitor.

Your description of MEMs based monitors is interesting it reminds me of the whole SED/FED display being built in the late-90s-early-2000s. https://en.wikipedia.org/wiki/Field-emission_display / https://en.wikipedia.org/wiki/Surface-c ... r_display

The sheer fact is human technology is horribly outdated. Why do we make displays with covering flaws cause apparently some people just like to waste time, money, and effort fixing something that should be thrown away. It's kinda like the US economy, it cannot be reset at this point in time it's too far gone into such levels that a reset cannot happen. Same with displays no one wants a clean fresh start everyone just wants to make as much money as possible from whatever insignificant baby steps available.

It's the nature of the beast and everyone suffers. Sure some newer stuff helps like OLED or Mini-/Micro- LED technologies or transistor illumination technology or aforementioned MEMs. But non-the less it's all about the money situation.

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Re: LPD: Laser Phosphor Display - Successor to CRT?

Post by Chief Blur Buster » 24 Oct 2020, 16:25

blurfreeCRTGimp wrote:
23 Oct 2020, 16:53
My issue is, your own writings about going blur free with brute force seem impractical, even with the great advancements you speak of.
But I am already doing it on my desk today (sort of).

I already have the ASUS PG259QN 360Hz monitor sitting on my desk, and my RTX 3080 can run 360fps in many games such as Bioshock Infinite and Crysis 2. I'm already getting strobeless blur reduction at less than 3ms real-world MPRT without needing a strobe backlight. We're already a third of the way to true CRT-quality strobeless bur reduction! 360Hz is `more than a third of 1000Hz.

And did you know ASUS already said they have roadmapped 1000Hz? They told me and PC Magazine.

I can read the small Street Labels of TestUFO Panning Map Test at 1080 pixels/second without a strobe backlight. No ULMB or LightBoost needed to read these street labels at that panning speed!

Yes, we are far away from 2000fps at 2000Hz, but refresh rates are improving geometrically and I've already seen a Japanese 1000Hz prototype. My realistic estimate for a mainstream brand is that true 1000Hz display is a reality by approximately year 2030. Could be sooner, but I am being conservative.
blurfreeCRTGimp wrote:
23 Oct 2020, 16:53
While awesome, that would be an insanely expensive rig, affordable to very few to get you not even half way to your goal by brute force.
4K was a $10,000 luxury in 2001. Today, 4K is a $299 walmart special. The 120Hz refresh rate is being commoditized 2020-thru-2029. Although Apple iPhone postponed 120Hz until iPhone 13, the Samsung Galaxy now has it, and a lot of popular competing smartphones now have high-Hz. Almost all 4K HDTVs purchased in 2020 has a hidden 120Hz feature. Soon, Dell is going to include 120Hz in generic office monitors (sometime between 2025-2029) when esports have moved on to 480Hz-1000Hz range by then. By year 2030, it will be hard to buy 60Hz-only screens unless intentionally looking bottom-barrel like today's 720p HDTVs.

Yes, believe it or not.... even 240Hz will be commoditized too (probably by year ~2040), as I expect commodity milestones to be ticked approximately once every 10 years, much like the journey from 1980 HDTV to 2020s HDTV. Since we've stopped flickering (CRT/plasma) to reduce motion blur, it forces refresh rates up as the ergonomic motion-blur-erasing method. Strobing will be obsolete. Maybe not in everybody's lifetimes. We've got a Refresh Rate Moore's Law equivalent occuring because it's the only way to have cake and eat it too (flickerless ergonomic + blurfree). And Blur Busters is part of surfing that wave of refresh rate race to retina refresh rates.

240Hz and 360Hz is not just for esports, it is great for web browser scrolling too! Just like the 120Hz iPad is a pleasure to surf the web on; if you have one of these iPads too, then you're already on-board the non-gaming high-Hz train (It's why some staid companies like DELL is now convinced, too -- though it's part of many companies' longterm roadmap to eventually eliminate 60Hz-only displays when 120Hz is a freebie feature)!

1000Hz isn't going to be expensive forever this century. Sure, it might not be within some of our lifetimes, but I'm working on commoditizing high refresh rates. Lifetime TestUFO visits have approached almost a hundred million (2012-2020), most of it in recent years. Unusually, asian countries (China, Taiwan, HongKong, Korea, Japan) have a very strong weekday bandwidth surge indicative of lots of copanies and manufacturers using TestUFO to improve their displays.

Yes, today, if you need cheap blurfree, you still want strobing, since strobing techniques is the only way to eliminate motion blur at lower refresh rates (like CRT never needed higher refresh rates to eliminate display motion blur).
blurfreeCRTGimp wrote:
23 Oct 2020, 16:53
Compared to my crappy little 20 year old $200 Sharp 14 inch Standard Definition CRT, the image is dark and looks like ass. The strobe backlight is also already failing in places. I don't say any of this with joy by the way, lol. The little TV also has color comparable to an OLED.
You'll need to upgrade to a good strobed "1ms IPS" soon. It's another century compared to that.
blurfreeCRTGimp wrote:
23 Oct 2020, 16:53
The video that Linus just did about the $1500 48 inch LG CX illustrated the issue well. That OLED murdered the also expensive 360hz LCD in clarity
At 120fps, yes.

Don't forget the scientific variables! At 360fps@360Hz, my 360Hz monitor has less motion blur than the OLED has. It does take brute framerate to compensate for LCD GtG slowness, yes. And the blur is slightly more asymmetric (e.g. looks like ~200Hz sample-hold blur at one edge, looks more like ~300Hz sample-hold blur on opposite edge) due to GtG being different speeds in the different directdions. If you hate asymmetry, you'll prefer OLED. But both edges of motion blur is still less than 120fps OLED. It's not apples vs apples, but the OLED cannot do 360fps @ 360Hz.
blurfreeCRTGimp wrote:
23 Oct 2020, 16:53
but has severe burn in issues
That'll only happen if you abuse the OLED. Just enable Windows taskbar authoide, use Dark theme, orbit, and stick to SDR at Windows desktop. It makes a kickass monitor. Sure, faint burn-in may show after 3 years but it's less worse than IPS glow, VA ghosting, or TN angles. The burn-in doesn't really become bad until long after you've already upgraded to a different panel.
blurfreeCRTGimp wrote:
23 Oct 2020, 16:53
is sample and hold
Which will eventually be superior at sufficient framerates, provided you have high framerates and refresh rates. (1000fps@1000Hz sample-and-hold blows away strobed in early laboratory tests).
blurfreeCRTGimp wrote:
23 Oct 2020, 16:53
requires native resolution to look its best
Overkill resolution helps. On an 8K panel, you can use a scaling algorithm that looks like a CRT at low resolutions.
blurfreeCRTGimp wrote:
23 Oct 2020, 16:53
and costs $1500. Not too mention the insane rig you need to run it at 120hz
True, running at 120Hz is still expensiveish today.
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Re: LPD: Laser Phosphor Display - Successor to CRT?

Post by ChaosCloud » 25 Oct 2020, 10:02

thatoneguy wrote:
22 Oct 2020, 18:37
The pictures you linked to look very soft, doesn't even look remotely close to 720p, it doesn't look sharp at all. Really bad focus, looks blurrier than a lot of old consumer CRT's even.
It really looks as blurry as an upscale. Heck it's probably doing uspcaling from 360p to 720.
It's at least 540p as it's able to resolve all lines on those scales. It does look soft in those images. One factor could be that it's projecting on a painted white wall which has some sub-surface scatter leading to softness.
mp-cl1_res.png
mp-cl1_res.png (290.67 KiB) Viewed 6615 times
thatoneguy wrote:
22 Oct 2020, 18:37
Another problem with it is that it's super dark and basically unusable in anything but a pitch black room.
Expecting a bit much from a ~7 Watt device?? The thing is smaller than the power brick of most monitors. It's side by side with a 188W 46" LCD in my comparison photo on avsforum and brightness is not far off.

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