[Blindmath] Braille cell size n Interpoint printing query

[George Bell]

Hi Ian,

Unfortunately your table didn't format in transit.

However, a common dimension in Europe is 2.5 millimetres centre to centre both vertically and horizontally with the cell being 1 millimetre at its base.

However, Interpoint braille places the opposing side's dots midway between rows both vertically and horizontally. So if you apply Pythagoras Theorem, the dots are actually approximate 1.75 millimeters centre to centre from the nearest dots on the other side.  For example in the middle of the square formed by dots 1,2,4,5 and dots 2,3,5,6.

I hope I've made that clear - it's been over 50 years since I did any math at all.

George.

-----Original Message-----
From: Blindmath [mailto:blindmath-bounces at nfbnet.org] On Behalf Of Ian Chris
Sent: 04 February 2014 15:08
To: blindmath at nfbnet.org
Subject: [Blindmath] Braille cell size n Interpoint printing query

Dear Members,

I was looking for the braille cell dimensions and came across the sizes adopted by various countries and standards, for eg:

 English Interpoint (braille on both sides of the paper) [9]2.292.546.00
10.411.4 - 1.5

The second column is the  center to center distance between dots in the horizontal cell, the third is the vertical distance, the fourth column is the distance between the center to center between the first and the second cell.

This is for a standard 6 cell. the value of 1.4 to 1.5 is indicated on the dot diameter column the one that shall be the diameter of the pin while printing it on paper too.

I fail to understand how the interpoint braille is printed with theses dimensions because as per this table the center to center distance that shall remain free considering the 1.4 dot diameter is(2.29-0.7-0.7) = 0.89.

So if the clear distance that is available in between the pin 1 and pin 4 is just 0.89 mm. Please help me in understanding this interpoint printing concept.

Regards,

Ian Chris
_______________________________________________
Blindmath mailing list
Blindmath at nfbnet.org
http://nfbnet.org/mailman/listinfo/blindmath_nfbnet.org
To unsubscribe, change your list options or get your account info for Blindmath:
http://nfbnet.org/mailman/options/blindmath_nfbnet.org/george%40techno-vision.co.uk
BlindMath Gems can be found at <http://www.blindscience.org/blindmath-gems-home>