There is a rapid growth in sensor technology in regions of the electromagne
tic spectrum beyond the visible. Also, the parallel growth of powerful, ine
xpensive computers and digital electronics has made many new imaging applic
ations possible. Although there are many approaches to sensor fusion, this
paper provides a discussion of relevant infrared phenomenology and attempts
to apply known methods of human color vision to achieve image fusion. Two
specific topics of importance are color contrast enhancement and color cons
tancy.