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A simple way to verify this is to observe that common mirrors also tend to be green, showing that the other colors are absorbed more by the mirror. If you face
by njdvndsjkvn 4y ago
A simple way to verify this is to observe that common mirrors also tend to be green, showing that the other colors are absorbed more by the mirror. If you face two mirrors towards each other you will see a lot of green.
edit: here's an example:
https://i.imgur.com/Ar80FYZ.jpeg https://i.imgur.com/Ar80FYZ.jpeg
- adrian_b 4y agoThe common mirrors have the metal on the back side, so their reflectivity is diminished by the absorption in the glass. The better mirrors, which are used e.g. in telescopes and some other optical instruments, have the metal on the front side, but that limits the metal choice to aluminum, because silver is tarnished quickly by the sulfur compounds present in the air.
- njdvndsjkvn 4y agoso why don't common mirrors just use aluminum? It's already cheaper than silver, right?
- adrian_b 4y agoThe common mirrors have been using aluminum for a long time. I do not know when aluminum has replaced silver, but it was probably not a long time after WW2. The silver mirrors had the advantage that the metal could be easily deposited from a water solution, anyone could make silver mirrors at home, if desired. The aluminum mirrors use a vacuum deposition process, which requires very expensive equipment, but the cost per mirror is much less.
- njdvndsjkvn 4y agoAh. I misunderstood your earlier comment. Thanks!