A compact disc has pits on its surface to represent the data bits.

Is the optical surface of a CD smooth as a mirror when new and blank, before anything is recorded/'burned' ?  Am after a small, light, thin, durable mirror if I can cut off from a new CD

Edited June 25, 20187 yr by Externet

Industrially manufactured CDs have pits which are mechanically pressed into the plastic by a metal master.

User recordable CDs don't have physical pits. They incorporate a chemical layer which undergoes a local chemical change when 'burned' with the laser writer. These have different optical properties and are equivalent to the pits, but can degrade over time or heat or high levels of illumination.

You would have to experiment with a CD or piece of one to see if it is specular enough for your purposes.

Thanks.

Just shot a laser to a new, blank, recordable disc and the reflection is not a single beam...  Suppose there is some formatting pits or tracks or something

Might be possible to diy. Aluminum, plastic and lacquer, maybe substituting  resin for the last two.

On 6/25/2018 at 1:10 PM, studiot said:

Industrially manufactured CDs have pits which are mechanically pressed into the plastic by a metal master.

User recordable CDs don't have physical pits. They incorporate a chemical layer which undergoes a local chemical change when 'burned' with the laser writer. These have different optical properties and are equivalent to the pits, but can degrade over time or heat or high levels of illumination.

You would have to experiment with a CD or piece of one to see if it is specular enough for your purposes.

What's a master?

Master is the original from which copies are made.

Along the same lines, you might have better luck with the internal platter of an old hard drive.
They are very smooth and reflective, but extremely brittle ( possibly glass ), so cutting a small piece might be a problem.

Edited June 9, 20205 yr by MigL