How does a screen work?

There are some sentences in this that are technically vague enough to pass, but I don't think are strictly speaking correct, and I believe will likely lead to a mistaken understanding:

> modern displays don't paint the image line-by-line (...) They light up each pixel simultaneously, refreshing the entire display at once.

The entire screen area is lit all the time now, yes, but refresh still typically happens line by line, top to bottom [0], left to right [0], for both LCDs and OLEDs. It's a scanning refresh, not a global refresh (sadly).

You can experimentally confirm this using a typical smartphone. Assuming a 60 Hz screen refresh, recording in slow motion will give you enough extra frames that the smartphone camera also likely operating in a scanning fashion (rolling shutter) won't impact the experiment. On the recording, you should see your screen refreshing in the aforementioned fashion.

[0] actual refresh direction depends on the display, this is for a typical desktop monitor

I was glad they at least mentioned how IPS (PLS) and VA differ from older TN.

But you're right both LCD and OLED refresh a stored voltage on the cell (or caps) on a roughly line by line (OLED can easily be 5 clocks on the GIP to cancel internal transistor offset voltages).

I was mostly annoyed that they didn't mention the circular polarizer on OLEDs. Although there is discussion of going to color filters with Quantum Dot OLED, the circular polarizer is what makes the blacks so black on mobile OLED devices.

Also, didn't really mention pentile RGGB sub-pixel pattern which is dominant in mobile OLED (which is more than 50% of devices). Now they're moving to "tandem" stacked OLED for higher brightness and lower current density, but no latteral sub-pixel pattern.

There were a few things I personally found lacking as well, albeit they're fairly minor.

Regarding CRTs, at the vector CRTs section, they mention "they were mostly monochrome and so the phosphor dots could be tightly packed" - this is not true either I believe, monochrome CRTs had a uniform phosphor coat on the inside, no subpixel patches. I'd have also liked if they delved a bit into the decay times of the various phosphor chemistries used for color CRTs, and how they compare to LCDs and OLEDs. It's an entertaining comparison, grounds motion performance related discussions really well.

Regarding LCDs, I missed the mention of multi-layer LCDs, especially since they bring up tandem OLEDs.

Regarding OLEDs, now that you mention, the subpixel layouts were left unaddressed.

Regarding quantum dots, I missed both the mention of QDEL as a somewhat promising future contender, and the mentioning of the drawback of their typical implementation. External light also provides them with energy to activate, which I believe is at least partially the cause behind the relatively poor black levels of QD-OLEDs in environments with significant ambient light (+ something about it not being possible to put a polarizer in front of them?)

I was also generally expecting a more in-depth look by the title, would have loved to learn about the driving electronics, maybe learn about why OLEDs aren't ran anywhere near as fast as their full potential (I'd assume throughput limitations), etc. Overall, it basically only covers as much as my own enthusiast but not in-the-area self gathered over the years too.

> Regarding CRTs, at the vector CRTs section, they mention "they were mostly monochrome and so the phosphor dots could be tightly packed" - this is not true either I believe, monochrome CRTs had a uniform phosphor coat on the inside, no pixel patches.

This is one of the reasons why emulated versions of Asteroids (arcade game) can never match the real thing: the razor-sharp, perfectly straight lines with zero aliasing used to paint the display. The computer also has fine-grained control of how bright to make the electron beam that raster displays typically don't allow (this is perhaps as simple as holding the beam in place, or drawing back and forth over the same line segment), meaning that your ship's projectiles and enemy shots appear as super-bright points with a phosphor bloom around them, glittering in the dark. Most emulators simply draw them as nondescript pixels. I suppose with some effort a CRT simulator can be hooked up to the emulator... but it still wouldn't be the same.

I'm glad I got to play an authentic Asteroids before I died. Working machines are getting rarer. Some of those who come after me may not get that chance.

My first and only time playing Asteroids in its original vector CRT glory was a bit shocking to me. I remember the evolution of CRTs in the 80s and 90s. My family had a small B&W CRT that fascinated me with its image quality, in that it always reminded me more of a b&w photo than color CRTs reminded me of color photos.

Still, that vector CRT that I saw perhaps a dozen years ago was quite a surprise. Lack of rastering and the utterly insane brightness sent me down a rabbit hole. I ultimately concluded I'm not ever likely to own a basement Asteroids cabinet.