[Elecraft] Blue Displays and Visual Acuity

[Kok Chen]

In the human fovea (where all the resolving mechanism is), there are  
fewer S-cones (blue sensitivity) than there are M-cones (green) and L- 
cones (red).

Quoting Malacara ("Color Vision and Colorimetry:Theory and  
Applications," ISBN 0-8194-4228-3): "[the Blue S-cones] do not  
contribute to contrast discrimination; thus they are not able to  
detect image borders."

You can further find a plot of red-green versus blue-yellow contrast  
sensitivity by searching for "Light Vision Color" by Arne Valberg in  
Google books and look for Figure 4.29 (page 195):

http://books.google.com/books?q=%22Light+Vision+Color%22+by+Arne+Valberg

Most of the compression techniques (including how digital camera  
sensors are manufactured) that involves color images make use of the  
fact that blue has little effect on resolution.  Blue cones contribute  
mainly to hue and chroma.

73,
Chen, W7AY