Lichtenberg Ratio
Posted: Thu Jul 28, 2005 9:01 am
Having wrongly supposed that the standard dimensions for sheets of paper (US Letter, A4, etc) would approximate the golden ratio, I recently lost a bet while learning the definition of the Lichtenberg Ratio:
The ratio of the square root of two to one.
This ratio is the basis for the standard ISO paper sizes (A4, B5, etc). It has the advantage that when a sheet with dimensions of this ratio is appropriately cut into halves, the resulting two sheets also have the same ratio (an A3 sheet cut in half yields two A4 sheets, etc.).
A consistent height-to-width ratio among page sizes has an immediate benefit for scaled photocopies. For example, the proportion of text to margins is preserved when copying a B5 page from a book to A4 paper. This is not true for US sizes, such as from US letter to US legal.
Thanks to KatyBr, whose new sig quotes Prof. Lichtenberg.
--Cliff
The ratio of the square root of two to one.
This ratio is the basis for the standard ISO paper sizes (A4, B5, etc). It has the advantage that when a sheet with dimensions of this ratio is appropriately cut into halves, the resulting two sheets also have the same ratio (an A3 sheet cut in half yields two A4 sheets, etc.).
A consistent height-to-width ratio among page sizes has an immediate benefit for scaled photocopies. For example, the proportion of text to margins is preserved when copying a B5 page from a book to A4 paper. This is not true for US sizes, such as from US letter to US legal.
Thanks to KatyBr, whose new sig quotes Prof. Lichtenberg.
--Cliff