Screen height comparison:Widescreen and Standard Aspect

jjknoll

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I have often wondered about how the vertical dimension of a widescreen monitor compares to that of a standard 4:3 aspect monitor. For instance, does a 22" widescreen have as much screen vertically as a 19" standard monitor?

If you are interested in seeing a comparison of some mainstream monitors and don't care about the math involved in figuring it out, skip to the bottom as I have listed the dimensions of some commonly purchased below.

The way to figure this is not overly complicated but may be somewhat hard to follow in text. The first thing we need to realize is the aspect ratio of both monitors. As stated above a standard aspect is in a ratio of 4 to 3. For every 4 inches in width it has 3 inches in height. Represented as 4:3. A widescreen ratio is 16:9. Every monitor is sold as diagonal inches. The distance from two opposing corners. Lower left to upper right or lower right to upper left. When measuring a widescreen the angle that is created by the two corners is less than that of a standard monitor. That angle can be calculated by using trigonometric functions on the triangle that is created with the diagonal, top and bottom sides of the monitor. The side of the monitor is the "opposite" side of the triangle and the bottom of the monitor is the "adjacent" side of the triangle in regards to the angle we are trying to find. All though we do not know the actual measurements of these sides, we do know the ratio in which they grow. This will allow us to find the angle without needing the actual measurement. By dividing the opposite side (3 for standard 9 for ws) by the adjacent side (4 for standard 16 for ws) we create two decimals. 3/4=.75 for standard and 9/16=.5625. By using the tan-1 function on a calculator we arrive at the angle of each diagonal measurement. Tan-1 .75=36.87 degrees for standard and tan-1 .5625=29.358 degrees for ws. These angles will now help us to find the height and width of each monitor size. To find the height of a ws monitor, use the sine fuction on a calculator with its diagonal angle and multiply by its listed size. "sin 29.358"=.490 * 22" monitor= 10.78" tall. The same is true for the standard; "sin 36.87"=.600 * 19" monitor= 11.4" tall. This shows a 19" standard monitor has 5/8 (.62) of an inch more screen vertically than a 22" widescreen. For the width, the cosine function is applied to angles. "cos 29.358"= .8716 * 22"=19.17" wide for ws and "cos 36.87"=.800 * 19"= 15.2" wide for standard. Math is awesome!

As promised, here are dimensions for some popular monitor sizes:

Widescreen

24" 20.92" wide 11.76" tall

22" 19.17" 10.78"

19" 16.56" 9.32"

Standard

20" 16.00" 12.00"

19" 15.2" 11.4"

17" 13.6" 10.2"

Hopefully, if you are deciding whether or not your next monitor purchase should be a widescreen this will give you another factor when considering which will better fit your application and/or desire.
 

logical2u

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Alright, I applaud you on your use of math and all...

But widescreen LCD monitors are at a 16/10 aspect ratio, not 16/9.

This means that the angle with Height as its corresponding side has a measure of 32 degrees (Approx).

This brings our 24 Inch LCD widescreen aspect-ratio monitors to a final dimension of approx 12.7 inches (Height) by 20.35 inches (Wide)

This is identical to Dell's own specifications for the display area on their 2407WFP. (Except for some rounding areas)

In order to calculate the dimensions of a widescreen monitor, then, use Diagonal Viewing Size x (Sin for height, Cosine for width) 32.

Widescreen TVs are indeed at 16/9, but they aren't typically used as computer monitors.

Here's a list (Widescreen, inches):

30 inch: 15.9 x 25.45
27 inch: 14.3 x 22.9
24 inch: 12.7 x 20.35
22 inch: 11.65 x 18.66
And etc, etc

A 5/4 (1280x1024) 19 incher is 11.86 inches tall, and 14.8 inches wide for comparison. That's what I use, and I just measured it to make sure it's approximately correct.
 

jjknoll

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All right, so it seems I may have got caught with my pants down a bit. However, the first article I read after a google search did have this to say
LCD monitors are available in two common formats (aspect ratios). The standard format (4:3) is the most familiar. Widescreen (16:9 or 16:10) monitors mimic the aspect ratio of the HDTV format and are an ideal choice for viewing and editing video. In addition, widescreens can easily display multiple documents side by side, so you can work in two or more applications simultaneously.
From this link http://products.howstuffworks.com/computer-monitors-buying-guide.htm So, hopefully I am forgiven. Thanks for the astute reply!

 
G

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16/9 or 16/10, the maths still works.

I just put your calculations into an excel spreadsheet so that I can simply substitute the screen size and/or the aspect ratio and immediately see the height and width of a monitor. It just works! Thank you. I'm agonising over my next monitor purchase and these calculations tell me the relative screen sizes of every monitor I'm considering, whatever it's shape or size.

The icing on the cake, of course, is that plenty of monitors now are 16/9, so you weren't wrong - you were just ahead of the game!
 

Terralm

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Haha, thinking a bit too deep here with the math. Your usage of trig correctly assumes the triangle formed by the diagonal and the sides to be a right triangle. Therefore, why not just use the Pythagorean theorem? Throw in a bit of similarity and easy math for the dimensions.

Standard
Let x be a variable. Base = 4x, height = 3x. Using Pythagorean theorem, the diagonal would be 5x.
Divide the screen size by 5, giving x. Multiply by 4 for base, or 3 for height.

Widescreen (16:9)
Same logic. Base = 16x, height = 9x, diagonal turns out to be around 18.36x.
Divide the screen size by 18.36. Multiply by 16 for base, or 9 for height.
 

georgehynes20000

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16/9 or 16/10, the maths still works.

I just put your calculations into an excel spreadsheet so that I can simply substitute the screen size and/or the aspect ratio and immediately see the height and width of a monitor. It just works! Thank you. I'm agonising over my next monitor purchase and these calculations tell me the relative screen sizes of every monitor I'm considering, whatever it's shape or size.

The icing on the cake, of course, is that plenty of monitors now are 16/9, so you weren't wrong - you were just ahead of the game!

Hi could you put the formula / excel spreadsheet on this website

Cheers
 

rjparker

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Dec 11, 2014
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For vertical height

Standard 4/3 aspect ratio:
Multiply Screen Size by 0.6

Widescreen 16/9 aspect ratio:
Multiple Screen Size by 0.49 (or by 0.5 for close enough)

Therefore a 20" screen is 12" vertical standard vs 9.8" (or 10" close enough) widescreen