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[XC] Oj101
03-11-2010, 01:02 AM
Alright, so you want to buy a new 30" monitor but you'd like to know the exact height and width of the panel. How do you do it? Simple. You need the following:


Horizontal size (hypotenuse) of screen
Aspect ratio


For my example, I'm going to use a 19" 16:9 aspect ratio screen.

We are going to be using the formulae

sin(tan-1 height/width aspect ratio)*diagonal for height, and
cos(tan-1 height/width aspect ration)*diagonal for width



Fistly, 9/16 to get a decimal aspect ratio: 0.5625
Using tan-1, we can work out the diagonal angle of the screen. tan-1 0.5625 = 29.358 , meaning the angle is 29.358° from horizontal.
Use the following formula: sin (tan-1 result) * (diagonal size, hypotenuse) : sin 29.358 * 19: sin 29.358 = (0.49067565355234651434427338183771) * 19 = 9.3228374174945837725411942549166 = 9.32" high
Use the following formula: cos (tan-1 result) * (diagonal size, hypotenuse) : cos 29.358 * 19: cos 29.358 = 0.87157342826278517733892936862199 * 19 = 16.559895136992918369439658003818 = 16.56" wide


So we can see that the HxW of a 19" 16:9 widescreen monitor is 9.32" x 16.56"

How often do you see people referring to 2 x 19" monitors side by side as an effective 38"? This is incorrect, to get 38" diagonal you have to QUADRUPLE the area - i.e. double the 9.32" height to 18.64" as well as the width from 16.56" to 33.12". To calculate the actual diagonal of two monitors (using the specifications from the above example), we use the following formula, otherwise known as Pythagoras' Theorem:


a² + b² = c² , where c is the hypotenuse


For two 19" monitors side by side, we retain a height of 9.32" and double our width to 33.12"
To work out our new hypotenuse, or diagonal size, we can do the following:


((9.32²)+(33.12²))sqrt, or
((9.32² = 86.8624) + (33.12² = 1096.9344) = 1183.7968) sqrt = 34.406348251449179331286630792993 = 34.41" = 34.5"


I hope that clears things up for anyone interested :)

.Logic
04-11-2010, 05:06 AM
Just remember you will need to factor in the width of the bezel.

Soulburner
04-11-2010, 08:21 AM
Just remember you will need to factor in the width of the bezel.
The bezel is not included in diagonal screen size, so why would it matter?

[XC] Oj101
04-11-2010, 10:28 AM
Yeah, and no amount of math will get you that :D

[XC] Synthetickiller
04-23-2010, 08:44 AM
What ever happened to looking up specs from the manufacturer's site? :shrug:

[XC] Oj101
04-23-2010, 01:58 PM
Who cares? :D

bmg
04-24-2010, 12:38 PM
http://lcdtech.no-ip.info/en/data/pixel.size.htm

[XC] Oj101
04-24-2010, 01:47 PM
I don't like you right now, a lot of brain-hurt went into my first post :(

.Logic
04-30-2010, 06:26 PM
The bezel is not included in diagonal screen size, so why would it matter?

Well there would be a bit of a problem if someone bought a monitor for a certain size space using the above calculations... Sure most bezels would probably be all right but there are many LCDs that have oversized bezels and speaker bars.

STEvil
04-30-2010, 09:56 PM
so... 2560x1600 @ 62" would give about the same PPI and pixel size as 1920x1080 @ 46"...


When will LCD manufacturers start making 2560x1600 or 2560x1440 larger than 30"?? :(

Soulburner
05-01-2010, 04:29 AM
I don't like you right now, a lot of brain-hurt went into my first post :(
That work is good for your grey matter :cool:

[XC] Oj101
05-02-2010, 05:39 AM
True, but it has caused degradation and I need to up my vBrain now :(

lowfat
05-02-2010, 08:15 AM
http://lcdtech.no-ip.info/en/data/pixel.size.htm

dood. you rule. :up:

No way in hell would you catch me doing all that math in the first post. :ROTF:

Darth_Penguin
05-06-2010, 07:51 PM
http://www.displaywars.com/

I find this site to be vital when shopping for monitors.