A very old thread with lots of ideas. Here are some that I didn't see.
No light goes through the disc. It all gets reflected, but the pits in the disc are 1/4 wavelength deep so that the light reflected from the bottom is 180 degrees out of phase with the light from the top surface, so there is interference, which looks like no light.
In a digital error correction system, the data stream includes redundant information so that the original data can be recovered without any error, provided that the transmitted data stream error rate does not exceed that which was anticipated in design of the encoding algorithms.
As I have mentioned before, modern digital transmission systems use error correction encoding so that they can be run at far higher bandwidth that that which would be necessary if error-free transmission were needed. The higher bandwidth more than makes up for the redundant data.
I never clean or otherwise process CDs. Except for one disc that was defective when purchased, I have never had a disc that failed to play, on several players and DVDs.
No light goes through the disc. It all gets reflected, but the pits in the disc are 1/4 wavelength deep so that the light reflected from the bottom is 180 degrees out of phase with the light from the top surface, so there is interference, which looks like no light.
In a digital error correction system, the data stream includes redundant information so that the original data can be recovered without any error, provided that the transmitted data stream error rate does not exceed that which was anticipated in design of the encoding algorithms.
As I have mentioned before, modern digital transmission systems use error correction encoding so that they can be run at far higher bandwidth that that which would be necessary if error-free transmission were needed. The higher bandwidth more than makes up for the redundant data.
I never clean or otherwise process CDs. Except for one disc that was defective when purchased, I have never had a disc that failed to play, on several players and DVDs.