LCD TVs
- Thread starter biferi
- Start date
DickCappels
- Joined Aug 21, 2008
- 10,068
Yes, they have pixel pitch.
Hello,
@crutschow , is the size of a TV not given as the diagonal of the screen?
Then the PPI will be diffrent as the side is smaller as the diagonal.
Bertus
@crutschow , is the size of a TV not given as the diagonal of the screen?
Then the PPI will be diffrent as the side is smaller as the diagonal.
Bertus
MisterBill2
- Joined Jan 23, 2018
- 15,709
Given that the pixels are cloe to square the pitch will be close to the same, vertical and horizontal.and possibly close to some published number. BUT the actual picture can be no better than what is being sent to the TV input connection. And once you have the set you are stuck with whatever pitch it came with. Getting the bigger screen does not buy you much better resolution.
Yes, the screen size is normally given as the diagonal since that gives the largest number for advertising purposes.
But if you notice, I used the width of the screen and the number of horizontal pixels, not the diagonal in my calculations.
For a 50" width, the diagonal would be about 57.4"
Last edited:
A 75" diagonal TV has a screen width of about 65.4".
The PPI would then be 3850pixels / 65.4" = 58.9 pixels / inch.
Did you not read my post #8?
As I said, 75 inches is the diagonal measurement.
The width is thus about 65.4" and the number of horizontal pixels is 3840, so the pixel pitch is 3840 / 65.4 = 58.9 ppi.
Just to but in, the diagonal measurement is historical, the original cathode ray tubes were circular and the the dimension given was the outer diameter of the glass tube. The maximum picture size was limited by the diagonal, which would be much smaller.
Last edited:
MisterBill2
- Joined Jan 23, 2018
- 15,709
It seem that some set makers use a stretchy tape when measuring that diagonal, and they round up to the next whole inch. And sometimes they will add the qualifier word "class" so that a 49.4 inch screen is a "50 inch clas" sized screen.
Crutschow does have it correct, though. The pixel pitch i based on the width, not on the diagonal.
I suspect that screen manufacturers probably work with metric dimensions anyway.
MisterBill2
- Joined Jan 23, 2018
- 15,709
Just think about the confusion if they start claiming diagonal sizes in millimeters!! Really impressive big numbers.I suspect that screen manufacturers probably work with metric dimensions anyway.
An easy way to increase the size of the picture, at no extra cost, is to move your chair closer.
They masked the top and bottom of the round screen but left the sides curved to give a somewhat rectangular picture (below), so the diagonal was the same as the width.
When they developed more or less rectangular tubes, they went to measuring the diagonal.
Last edited:
