The absorption of different laser wavelengths by xanthophyll, melanin, deoxyhemoglobin, and oxyhemoglobin. Note that, in general, there is less absorption as one moves to the redder end of the spectrum. This explains the need for more power and a resultant deeper burn with longer wavelengths. Note that diode yellow hits a peak of oxyhemoglobin absorption relative to diode green. This results in a slightly different effect between the 2 colors when treating microaneurysms. It is not clear if the difference is clinically significant. Finally, the graph shows why it is dangerous to use blue wavelengths to treat the retina, given the profound uptake of that color by xanthophyll pigment in the macula.