03.26.06
Critical Knowledge for the 21st Century
On the review for the Amazon.com: Westinghouse W32701 27″ Widescreen LCD Flat Panel at Amazon:
A 4:3 TV is a 3-4-5 Right Triangle. Divide the Diagonal measurement By 5 then multiply that number by 3 to get the picture hieght, or by 4 to get the width.
A 16:9 TV is a 16-9-18.36 Right Trangle. Divide the Diagonal measurement By 18.36 then multiply that number by 9 to get the picture hieght, or by 16 to get the width.
Rule of Thumb:
17″ Widescreen = 15″ 4:3 Picture Height
23″ Widescreen = 19″ 4:3 Picture Height
27″ Widescreen = 22″ 4:3 Picture Height
30″ Widescreen = 24″ 4:3 Picture Height
33″ Widescreen = 27″ 4:3 Picture Height
44″ Widescreen = 36″ 4:3 Picture Height
See? That’s nice, well written, succinct, right to the point, straight forward, not redundant and non-redudant.
The one piece they forgot to add was that LCDs don’t have the overscan area that CRTs do. That means that the CRTs have an effective screen size that’s an inch or three smaller than the listed size.
So if Amy and i are going to replace our ancient 22″ (circa 1988!) CRT, we could probably get away with a 23″ widescreen. But I think a 26 or 27″ display would be a better bet.