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TV resolution


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#1 of 3 sang

sang

    Auditioning

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Posted May 17 2003 - 07:11 AM

I have a question about TV resolution (CRT). Is the resolution a function of the phosphor screen or is it a function of the electron gun that scans the pictures? That is, are the phosphors laid down in rows and columns which determine the horizontal and vertical resolution, or are the phosphors densely laid down and it is the number of rows and columns that the gun scans that's the limiting factor? What are the vertical lines I can see on my TV screen when it is turned off? Are they the rows of phosphors? I'm just curious. Thanks.

#2 of 3 Allan Jayne

Allan Jayne

    Screenwriter

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Posted May 17 2003 - 02:49 PM

Yes, all of what you said is true and affects the resolution.

There is a limit to how small the phosphor dots or stripes can be made, and also when they are really small (or thin) screen brightness before burn-in becomes a problem is less.

In my opinion, if the electron beam spans any two of the phosphor colors (or half of one color, all of a second color and half of the third), and dark spots of like size are on both sides then the CRT can resolve details that small.

For an RPTV the vertical lines on the screen are not phosphor striped but are part of the optical system. I rate the resolution as based on a spot 1-1/2 times the spacing of those stripes.

Video hints:
http://members.aol.c...nejr/vidres.htm
.

#3 of 3 Mike Hamilton

Mike Hamilton

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Posted May 18 2003 - 12:01 PM

Resolution is ultimately determined by the bandwidth of the chassis, and not necessarily the dot pitch of the phoshor.
If the electronics limit signal bandwidth, high frequency detail will never reach the CRT for reproduction.
Michael Hamilton
The Real Picture
Scottsdale, Arizona