kijanki
"Geoffkait, pure matte black has 100% absorption of all colors."
that cannot be true since adding gree to the CD tray improves the sound. Almost all CD trays are black or black matte. As I said you can see for yourself with a red laser poster how much is reflected off the black tray.nalso, of the black matte tray was actually 100% effective the green pen wouldn’t make any difference. Nor would painting the tray cyan. And we know that’s not true.
"Other colors are used only to reflect only one color."
I don’t think we’re on the same page. You want to absorb color not reflect it. For a given color there is a complementary absorbing color.
Furthermore, dare I even say it? Black around the outer edge of the CD actually hurts the sound. 😀
"Targets for infrared, for counting number of pulses in rotational speed measurements, are usually gold/matte black (including one I designed:
http://himmelstein.com/images/product-datasheets/0807545dc201B8701.pdf )
As I mentioned before you can see infrared with your phone camera and test it for yourself."
the reason you see the infrared is because it’s near infrared next to the visible part of the spectrum thus part of the signal is in the red zone. Same for a CD laser. Hel-loo!