[Pick Axe]

Originally Posted by SoLiDUS

Blue diodes have been developed, but are under patent monopoly and hence very expensive. The diodes are large rectangular boxes; no laser pointers have yet been developed. Blue laser light does not appear as bright as green because the lower wavelength (473nm) is not as visible to the eye as green.Violet, with a lower wavelength than blue,is still less visible.

I heard something a couple a years ago about using blue lasers to make cds because it has a smaller beam so you can fit more data in the same place.