3 ms·

Eh. It's sort of true. While the screen has individual phosphors, they're not individually addressable. What is sent is an analog signal that indicates intensit

Eh. It's sort of true. While the screen has individual phosphors, they're not individually addressable. What is sent is an analog signal that indicates intensity (of a specific channel) at the current time. As an analog signal, it cannot change instantaneously. Instead you get a bunch of waves indicating varying intensity of each channel over time. Pixels in frame buffers get mapped to time slices in that signal. The DAC attempts to create the correct wave to match the framebuffer data, but it's always going to have analog fuzziness at the physical level. And if you have a higher-frequency DAC, you can map more pixels to the same amount of time, and then get higher horizontal resolution. Of course, that's all for horizontal lines. The number of vertical lines is actually part of the signal. It's just that there's a lot of fuzziness in how many times you can subdivide an individual line.

pengaru 3y ago
The Shadow Mask produces what are effectively discrete pixels though, no? https://en.wikipedia.org/wiki/Shadow_mask https://en.wikipedia.org/wiki/Shadow_mask
- chowells 3y ago
  There are discrete phosphors that light up separately. They are not addressable discretely. They do not have the same count or density in every display. They provide an upper bound to how fast your display hardware can react to changes in the input signal. But they aren't pixels in the traditional sense. They're phosphors.
  - danparsonson 3y ago
    This is all a bit of a strawman though - transport yourself back in time before LCD monitors and most people were comfortable referring to the glowing squares on the screen as pixels. That you now define a pixel as a physically distinct separately-electronically-addressable unit doesn't change that.
    - ftaghn 3y ago
      It is no strawman. Because a lot (most? all? I don't recall, but that was my experience) of monitors in the CRT days had resolutions that went much higher than the true ability of the monitor to show detail, so it really matters to understand that those 'glowing squares' as you call them are totally unrelated to pixels. Setting higher resolutions on those monitors didn't relate to getting more detail out of your picture. I've sometimes seen people on HN argue that CRTs could go as high or higher than early LCDs in resolution, but what those people never say is that those "high" resolutions looked very blurry compared to a LCD. People only cranked up the resolution if they wanted more room to work with, not more details. Personally I was always more comfortable with the lower resolutions on such displays, plus, because of the way the tech worked, CRTs were limited in refresh rate at their peak resolution and in my opinion they were atrocious to look at if they were run at 60 hertz. On the other hand, LCDs were very bad at showing any resolution other than native, which made them very bad for gaming as any time you needed to drop the resolution to run a game at a decent framerate you would be stuck with a blurry image. Plus, even today's high refresh rate LCDs are worse at motion than CRTs due to sample-and-hold. All in all, it was difficult to tell whether you would like a CRT before buying it, as it wasn't well advertised how sharp the picture would look at X or Y resolution. With LCDs at least that part is not a problem. If it says it can display 4k density of pixels, that is what you get. You will still need to judge them for their viewing angle, latency, or quality of color, but detail is no longer an issue.
      - chowells 3y ago
        For what it's worth, I think a lot of the blurriness people are referring to with early LCDs is motion ghosting. It was terrible for several years, and it made anything in motion a blurry mess. I definitely remember early LCDs as blurry for games because of that.
    - fluoridation 3y ago
      It doesn't matter what those people used to say. The word "pixel" has (and had) a specific meaning that's not analogous to what goes on on the surface of a CRT; at least, not on the horizontal axis. If some people mistook the metal mask in front of the phosphor for a grid that separates individual pixels, then they were simply wrong.
- kalleboo 3y ago
  The beam still keeps modulating its strength even in the middle of a hole in the shadow mask, so you can get, say, "half-pixels" (which are more of a smear, since this is analog and not digital). (or more likely, your hardware can't change pixels fast enough between the holes in the shadow mask so pixels are smeared out)

pengaru 3y ago

The Shadow Mask produces what are effectively discrete pixels though, no? https://en.wikipedia.org/wiki/Shadow_mask https://en.wikipedia.org/wiki/Shadow_mask

chowells 3y ago
There are discrete phosphors that light up separately. They are not addressable discretely. They do not have the same count or density in every display. They provide an upper bound to how fast your display hardware can react to changes in the input signal. But they aren't pixels in the traditional sense. They're phosphors.
- danparsonson 3y ago
  This is all a bit of a strawman though - transport yourself back in time before LCD monitors and most people were comfortable referring to the glowing squares on the screen as pixels. That you now define a pixel as a physically distinct separately-electronically-addressable unit doesn't change that.
  - ftaghn 3y ago
    It is no strawman. Because a lot (most? all? I don't recall, but that was my experience) of monitors in the CRT days had resolutions that went much higher than the true ability of the monitor to show detail, so it really matters to understand that those 'glowing squares' as you call them are totally unrelated to pixels. Setting higher resolutions on those monitors didn't relate to getting more detail out of your picture. I've sometimes seen people on HN argue that CRTs could go as high or higher than early LCDs in resolution, but what those people never say is that those "high" resolutions looked very blurry compared to a LCD. People only cranked up the resolution if they wanted more room to work with, not more details. Personally I was always more comfortable with the lower resolutions on such displays, plus, because of the way the tech worked, CRTs were limited in refresh rate at their peak resolution and in my opinion they were atrocious to look at if they were run at 60 hertz. On the other hand, LCDs were very bad at showing any resolution other than native, which made them very bad for gaming as any time you needed to drop the resolution to run a game at a decent framerate you would be stuck with a blurry image. Plus, even today's high refresh rate LCDs are worse at motion than CRTs due to sample-and-hold. All in all, it was difficult to tell whether you would like a CRT before buying it, as it wasn't well advertised how sharp the picture would look at X or Y resolution. With LCDs at least that part is not a problem. If it says it can display 4k density of pixels, that is what you get. You will still need to judge them for their viewing angle, latency, or quality of color, but detail is no longer an issue.
    - chowells 3y ago
      For what it's worth, I think a lot of the blurriness people are referring to with early LCDs is motion ghosting. It was terrible for several years, and it made anything in motion a blurry mess. I definitely remember early LCDs as blurry for games because of that.
  - fluoridation 3y ago
    It doesn't matter what those people used to say. The word "pixel" has (and had) a specific meaning that's not analogous to what goes on on the surface of a CRT; at least, not on the horizontal axis. If some people mistook the metal mask in front of the phosphor for a grid that separates individual pixels, then they were simply wrong.
kalleboo 3y ago
The beam still keeps modulating its strength even in the middle of a hole in the shadow mask, so you can get, say, "half-pixels" (which are more of a smear, since this is analog and not digital). (or more likely, your hardware can't change pixels fast enough between the holes in the shadow mask so pixels are smeared out)