What is this PCB component from an older CRT display?

07
2014-07
  • Samik Sengupta

    I have an old CRT Display that used to dim out every morning and would require significant warmup before it reached normal brightness. A repair guy worked on it. He did some stuff and asked me to notify him if the problem reappears again. The Display is working for now.

    After he left, I discovered that a PCB component left outside, which I suspect is a CRT Display component. I'm posting / linking a Photograph with my Question so anyone savvy with Display hardware can identify it and tell me if it's anything crucial or am I entirely mistaken.

    A Photograph is provided below:

    The Component I cannot Identify

    • Answers
  • pataluc

    the 6 components on the top are buttons... don't you have 6 buttons on your CRT? if so, it looks like he replaced the buttons' PCB.


    • Related Question

    Does subpixel rendering technology such as ClearType have any effect on CRT displays?
  • GeneQ

    If I understood correctly, subpixel rendering was originally designed to improved anti-aliasing of text on LCD screens. It makes use of the fact that each pixel on a color LCD is actually a bunch of individual red, green, and blue subpixels and does some magic with them to make text sharper. The physical properties of a CRT display is quite different. So, does subpixel rendering still work on CRT displays?


    • Related Answers
  • 8088

    Not as such. The results vary from screen to screen between "blurry mess" to "nice and clear".

    Most computer monitor CRTs have a shadow mask which has a triangular arrangement of colors.

    enter image description here

    Here there is clearly no way that subpixel rendering can work the way it should. However, you still get the difference in brightness and CRTs being blurrier than LCDs may make the text appear similarly to conventionally-smoothed text (which uses just grayscale to smooth the edges).

    Some computer screens have an aperture grille and I happened to use one of those for several years.

    enter image description here

    Here you can actually have a similar effect as on LCD screens for ClearType, especially when hitting the maximum resolution of the display (I tended to do so because my eyes work and I valued the space on screen :)). However, there is no guarantee that every pixel will lie exactly at the boundaries you would like it to lie. Also with older monitors the dimensions of the image tend to vary with overall brightness of the image. But at least for me subpixel rendering on such a screen was superior to grayscale antialiasing.

  • Daniel S

    When I used a 17" CRT on it's maximum resolution (1280*1024), I enabled subpixel rendering and it actually looked better.

  • Thomas Schultz

    Sounds like it kind of works but not nearly to the same effect as the LCD screens.

    http://www.microsoft.com/typography/cleartypefaq.mspx

  • Jonathan C Dickinson

    It depends. If you ask two people about the difference between MP3 and a FLAC you will get vastly different results - it depends how fussy you are.

    Technically you should get color bleeding instead of clean edges; but chances are you wouldn't notice it. Especially if the dot pitch is low enough - which CRTs are good with these days.

    Back in the stone age when I used CRT I enabled it and as Daniel said the quality was better, for me at least. I saw absolutely no color bleed (even on a crappy $80 CRT at that) and had reduced eye strain.

  • Lưu Vĩnh Phúc

    Although Cleartype was not designed specifically for CRTs, but many years ago, I tried enabling Cleartype on my CRT and it greatly improved text quality than before. But the effect maybe less than LCDs because the difference in pixel layout. Currently you can try Mactype which has a profile for CRT rendering, or you can create your own profile

    mactype profile