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CSS CSS Foundations Values and Units Absolute Length Units

Bret Hazelwood
Bret Hazelwood
4,069 Points
Posted by Bret Hazelwood
Bret Hazelwood
4,069 Points

smallest point a screen can display

This question says "equal to 1/96 of an inch, this unit is the smallest a screen can display". different screens have different resolutions sometimes within the same screen size so don't screens vary in pixel sizes??

2 Answers

James Barnett
James Barnett
39,199 Points
James Barnett
James Barnett
39,199 Points

> so don't screens vary in pixel sizes

Nope, to solve this problem there's such a thing called a reference pixel.

> The reference pixel is the visual angle of one pixel on a device with a pixel density of 96dpi and a distance from the reader of an arm's length. For a nominal arm's length of 28 inches, the visual angle is therefore about 0.0213 degrees. For reading at arm's length, 1px thus corresponds to about 0.26 mm (1/96 inch).

source: http://www.w3.org/TR/css3-values/#reference-pixel

You can read more about this brave new world of reference pixels

http://alistapart.com/article/a-pixel-identity-crisis/

Alex Lavender
Alex Lavender
2,471 Points
Alex Lavender
Alex Lavender
2,471 Points

I believe its a pixel also known as a px