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by dbttdft 822 days ago
OLED can easily be implemented with black frame insertion. You could even do it yourself at from the GPU/software level given a sufficiently high refresh rate if the monitor units are still too stupid to provide it as a working option. I'm more worried about the terrible spectrum of light they emit as with seemingly all LED tech, and the viewing angle.
2 comments

My Sony Bravia from 2020 is visible from any angle and can be configured to do black frame insertion.
In theory yes. You’d need a sufficiently high refresh rate (1000 Hz or better I would guess) and corresponding brightness.
The human eye is only sensitive at about 250hz, and even then it is only for brief flashes, as opposed to continuous motion. 1000hz is overkill.
What are you even talking about, an OLED running at 100Hz with BFI already would have zero motion blur. I'm not sure whether or not that's implemented yet but it's just a matter of time before the shitshow of monitor vendors figures that out.
You need shorter pulses than 10 or 5 milliseconds to reduce motion blur down to the level of CRTs. 100 Hz would only be sufficient if the BF takes up > 90% of the time, instead of the usual 50%. What causes motion blur is the frame being held for a period of time. BFI merely reduces that time by half. On CRTs, each pixel is only held for 100 microseconds or so.
Hmm, I haven't thought this far into it, what matters is probably how long the persistence of vision of the human is.

For the LG CX OLED (https://tftcentral.co.uk/reviews/lg_cx_oled) (oddly one of the only OLEDs that have BFI) we can see they have no problem pulsing the pixels on on for only 3-4ms (https://tftcentral.co.uk/images/lg_cx_oled/bfi_120_high.png) (5ms divisions), resulting in these images (which I can't tell how representative of a human are because I don't know if the camera exposure matches human vision and the camera is probably wobbling at such high speeds, adding more blur than a human would see which is why these pursuit camera pictures are always blurry to hell - IIRC all those LCDs from the last 6 years with half working BFI aren't actually blurry, they are just buggily implemented so they have the top of the screen and/or bottom showing double images, each image is crisp, just doubled):

https://www.tftcentral.co.uk/images/lg_cx_oled/pursuit_120hz...

https://tftcentral.co.uk/images/lg_cx_oled/pursuit_60hz.jpg

If you just take a 240Hz OLED and blank 3/4 frames to get back a 60Hz image I'd be half surprised if that actually looks blurrier than a CRT.

EDIT: yup, just tested one of my garbage LCDs even on 75Hz with BFI enabled in the monitor menu, the image is perfectly crisp, just there are artifacts everywhere, mainly double images. That wouldn't happen with OLED with BFI (with BFI in the hardware/firmware obviously to minimize the on time beyond just dividing the frame rate).

On second thought I think duration of persistence of vision (or afterimages) doesn't matter, but more the velocity of the object which your eye is following and the amount of angular "resolution" your eye can perceive. If your focus moves X amount while the object is lit, if that distance is more than the angular "resolution" your eye can perceive, it will appear as some blur behind the object.

You made me think about an interesting point I long avoided going into.