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There is big difference between 10000 nit backlight of full screen and 10000 backlight of a small spot which is scanned over whole area. Second option results in much smaller overall brightness. If 10000 nit spot covers 1% of screen area then you get a 100 nit display.

MEMS laser scanning might be technically feasible but it would likely expensive and bulky since you would need quite a bit of space behind the screen to guide the beam, similarly to CRT. Hence, I would not expect that this approach will be used in consumer electronics.

I don't think it would be that bulky, since you wouldn't be using the MEMS scanner to draw an image on a wall like with the projector, but just to draw a line of bright white light that you could sweep from top to bottom. That little projector is tiny, and today you can buy one for $260 retail.

If the laser was illuminating a phosphor layer, you would get very very bright light at very low power usage. Not too mention a huge boost to an LCD's native contrast ratio because the only part of the back light on at any moment would be where the beam was. You would not suffer a loss of brightness due to scanning, since scanning is inherent to the technology.

You could also scan at faster than 60hz, potentially way way faster, and reduce flicker from strobing, even at lower refresh rates on the LCD.

Optics might need to be involved, but I don't see the screen being thicker as a huge issue.

Cost would be an issue at first, like any new technology. However, I think if you compare this idea to say a dual cell LCD, (which is as good as I have ever seen a large LCD screen) it would be way cheaper at scale.

It Takes way less material to make a MEMS scanner than to build two full VA LCD layers stacked on top of each other.

LCD manufacturing today is already dirt cheap as it is, and that Highsense ULED XD costs substantially more than an OLED.

If I remember correctly, the chief said LED's in back lights would need 137x improvement in peak brightness to be able to get equivalent brightness of non strobe displays while strobing. This would accomplish that goal without the power draw, without the heat, and without complicated cooling.

You could already build an insanely bright backlight today with some of the LEDs in that Imalent MS18 flashlight, but the cooling required, and power draw would be insane.

The Chief has lauded the Quest 2 LCD as being the best he has seen, but that is a VR specific mobile display, and as the chief himself has stated, large displays are nowhere near caught up.

IDK it just seemed like an idea that could literally fix many of LCDs issues in one swoop.

It doesn't matter if you strobe, let the backlight constantly ON or whatever. If you want to achieve specific level of perceived brightness, all that matters is efficiency of light source. You can't fake brightness with strobing in region where flicker fusion occurs, see Talbot–Plateau law. So the only way that the laser+phosphor method could save power is that laser+phospor system would have higher efficiency of converting electricity to light than white LED. I would like to point out that you would need a blue/UV laser diode and also that white LED is in fact composed of blue/UV LED with white phospor. So I don't really see room for an efficiency breakthrough here.

MCLV wrote: ↑

16 Mar 2021, 17:06

I would like to point out that you would need a blue/UV laser diode and also that white LED is in fact composed of blue/UV LED with white phospor. So I don't really see room for an efficiency breakthrough here.

This is correct. LED edgelights have become really efficient as of late. There are other further efficiency improvements possible such as polarized backlights in sync with the polarized LCD alignment — https://www.laserfocusworld.com/optics/ ... efficiency