# how to understand the dot-pitch and the pixel resolution of a CRT monitor?

N

#### netwom

Hi all,

I don't understand the dot-pitch and the pixel resolution of a CRT monitor.

The RGB triads(triple-dots) sometimes corresponds to a pixel, sometimes
don't corresponds to a pixel: in this case, 1.5(or some other numbers) of
RGB triads consists of a screen pixel.

R G B R G B R G B...
G B R G B R G B R ...

I want to understand for a multi-sync monitor, suppose it has a "native"
resolution of 1600x1200, at this resolution, one screen pixel corresponds to
the one RGB triad... I understand this.

But how does this CRT monitor supports other resolution, such as 1024x768,
800x600, etc....

Anybody know how?

Thanks a lot,

-Lucy

G

N

#### netwom

Zagan said:

Hi Zagan,

Thank you very much! This one is very good tutorial. Thank you very much.

But it still does not address how the monitor group R G B dots together in
order to form different resolution.

For the native maximal resolution of a CRT, it is easy to understand, for
example 1600x1200,

Every three closest neighbor of RGB will group together to become a pixel.

But the same screen can display in a resolution of 800x600, 1024x768, etc.

How does the CRT select which three gun dots to lighten up when it displays
different resolution?

Thank you,

N

#### netwom

Nathan McNulty said:

Hi, I've read that page. Thank you. But I still don't understand:

For that RGB triad, suppose our dot pitch is 0.28mm.

For a pixel at the maximum native resolution, three closest neighboring RGB
group to be a pixel:

Then horizontal distance between two horizontally adjacent pixels is
0.28mm*0.866=0.24mm.

The vertical distance between the two vertically adjacent pixels is 0.28mm
itself.

So the pixel per inch(PPI) resolution for horozontal and vertical pixels
will be different.