|MadSci Network: Computer Science|
I hope you've asked this question in a spirit of fun, because it's really beyond the scope of most individuals to build a CD player from scratch. The chips are readily available, and there's lots of data books with application notes containing circuit diagrams, but the electromechanical portion (chiefly the laser assembly) would be extremely difficult.
However, if your question pertains to the technology of the disk itself and how the data is stored, then I'll refer you to the 'Consumer Electronics Design Education Project' Electrical Engineering course at the University of Washington. They have some relevent information at the following:
There's also a great book on the subject called 'The Compact Disk Handbook' by Ken Pohlman.
Have a great day!
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