As can be seen in this page of the book “Vision and Art: The Biology of Seeing” (Livingstone, 2008), the blue part of the spectrum aligns with our Rods which are the majority of our sensing cells (about 120 million rod cells and 6 million cone cells (

This then is an indication that using warmer colours for computer screens would be less strenuous on the eyes, since less brightness enters the eye outside of the main area of visual focus.

Livingston also points out that we have twice the amount of red cones as blue cones and I take that as suggesting it takes less work to extract information from a warm screen than a colder screen.