December 2011

Comparing Standard Screen vs Widescreen TVs

How do you really compare the screen sizes of old screen TVs to widescreen TVs? 
The key is to look at the heights of the screens. For instance, for a standard (old) 27" diagonal screen, 
the height is about 16.2". But for a wide screen with a 27" diagonal, the height is only 13.24". 

The aspect ratio of old screens is 4:3, where 4 is the width and 3 is the height. 
The aspect ratio of widescreens is 16:9, where 16 is the width and 9 is the height. 
So what's the formula to figure out the height given you have the diagonal?

For the standard 4:3 screen, the height can be calculated by this formula:

  height^2 = diagonal^2 / 2.77777

Meaning height squared = diagonal squared divided by 2.77777.

For 27" diagonal: height^2 =  729 / 2.77777, so height = 16.2"
For 35" diagonal: height^2 = 1225 / 2.77777, so height = 21.0"

For the wide 16:9 screen, the height can be calculated by this formula:

  height^2 = diagonal^2 / 4.16049

Meaning height squared = diagonal squared divided by 4.16049.

For 27" diagonal: height^2 =  729 / 4.16049, so height = 13.24"
For 32" diagonal: height^2 = 1024 / 4.16049, so height = 15.69"
For 42" diagonal: height^2 = 1764 / 4.16049, so height = 20.59"
For 50" diagonal: height^2 = 2500 / 4.16049, so height = 24.51"

End.

a_evangelista@netzero.com