Everything on the site seems high quality, very much looking forward to the upcoming articles
How does a screen work?
61–70 of 111 posts
Re: How does a screen work?
#62Not only was the initial diagram all/explaining, but the "pop"-"pip" on zoom-unzoom of the image was just as nice as playing with a sheet of bubble wrap. Wow, and that ruler on the right side, even with the sound. One of the nicest pages I have been on. And the landing page... https://www.makingsoftware.com/ It just keeps on giving.
Agreed, very talented communicator. Reminds me of the wonderful work of Bartosz Ciechanowski
Re: How does a screen work?
#63Not only was the initial diagram all/explaining, but the "pop"-"pip" on zoom-unzoom of the image was just as nice as playing with a sheet of bubble wrap. Wow, and that ruler on the right side, even with the sound. One of the nicest pages I have been on. And the landing page... https://www.makingsoftware.com/ It just keeps on giving.
So crisply done. I wish if Dan writes textbooks for all science & math books for High School students. World would be a better place for those who struggle to understand academics.
Re: How does a screen work?
#64There 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
Re: How does a screen work?
#65I can appreciate these articles as they are but I personally don’t like them. They are junk food level of infotainment to me. Something I’d find on a Wikipedia summary section that covers general points. A CRT - to name one - is a device whose actual understanding will challenge people in profound ways. To ask “how does a screen even work?” and to begin to answer this question will require a bit more than a summary f…
Sure, but I sent this to my nerdy early teen nephews and they actually liked it! This is no small feat.
Re: How does a screen work?
#66There 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…
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.
Re: How does a screen work?
#67There 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…
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…
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.
Re: How does a screen work?
#68There 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…
Indeed, one feature of active-matrix (and even passive-matrix) displays is that it needs only m + n signal lines to address a pixel in an m + n display. To change the color of a pixel, a signal goes out over the lines corresponding to the row and column of the addressed pixel, selecting it; and then another signal is transmitted over another line to actually change the value of that pixel. In this scheme, it would be impossible to address all pixels simultaneously. Nor would you actually want to, as this would require millions of control lines to drive the display!
Re: How does a screen work?
#69Earlier quoted context omitted.
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…
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 p…
> 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.
Re: How does a screen work?
#70LCD on paper you see lots of drawbacks, in practice modern state of the art LCD for TV is pretty damn good. We will soon have RGB LED Backlight LCD with WHVA+ Panel that is about as wide angle as IPS, 95%+ REC 2020 colour, and 1-2ms response time. Phosphorescent blue OLEDs should reduce current OLED display energy usage by 20-30%. But it still seems to be way off for phones and mass usage.
I think it's fairly common for technologies to get really good just as they're becoming obsolete. Vacuum tubes, CRTs, optical disks, photographic film... in fact, they're often in some respects better than the early generations of the technology that replaces them. But OLEDs just have too many advantages where it actually matters. Much lower power consumption, physically more compact (no need for backlight layers), e…
For me, OLEDs fall into a category exemplified by Anton Gudim's "YES, BUT" comic series.
YES, OLEDs consume less power, offer truer color reproduction, and are physically more compact.
BUT, they are prone to CRT-like burn-in.
SSDs, the same thing.
YES, SSDs are much faster and immune to mechanical failure.
BUT, they tend not to last as long as HDDs due to limited write cycles, and their price per GiB is still much higher.