On Thu, 24 May 2007 08:56:32 +0100, Jim Lesurf
wrote:

In article , Don Pearce
wrote:
On Wed, 23 May 2007 17:27:25 +0100, Steve Swift
wrote:

I probably know more about how CD's work than 99.99% of the population
since my honours degree in Physics contained a generous section on
optics, my secondary subject, Electrical engineering brought me into
daily contact with electronics, my post-graduate work in the Physics
department at Birmingham University and the Rutherford Laboratory in
Oxfordshire included daily use of lasers. I've owned CD players since
1982 (when the biggest problem was finding a CD, let alone knowing how
they worked).

But then what do I know? I'm just a Physicist with an electronics hobby.

I simply don't believe you. Nobody who understands how CDs work would
have written what you did. Were you asleep in class?

Actually, now I read more closely what you have just written, none of
that would of itself give you any insight into how CDs work. Optics
doesn't do it, Electrics doesn't do it and lasers don't do it. Digital
signal processing and audio are the disciplines relevant to the case.

Well, an understanding of lasers and some parts of optics would help with
understanding how the physical data patterns are tracked and read. So they
are relevant, but far from being all that is required.

Slainte,

Jim

Not really. This is all about what happens to the data once it has
been read from the disc - the mechanism by which it is read has no
bearing.

d

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