Image
from Oregon Medical Laser
Center
|
Phthalocyanine works in a different
way to the other dyes. When the recording laser heats
the dye it causes it to melt. As it melts the polycarbonate
layer below the dye expands to fill the gap. This melted
"blob" effectively diffuses the light enough
to resemble the bumps on a standard CD.
As with cyanine, this dye can be stabilised by the coordination
of a metal. Tin and titanium appear to be the best metals
for the required optical properties. |
