I thought of this like years ago, but I didn't have the equpiment to make it. They beat me to it.
Two additional laser beams are directed at the left groove wall and the right groove wall just below the tracking beams. Modulation on the individual grooves is reflected to scanner mirrors and onto left and right photo optical sensors. The variations of the modulated light cause the audio sensors to develop an electrical representation of the mechanical modulation of the grooves. The entire sound reproduction chain is analog.
That was the easy part.
The distance from the surface of the record to the traveling pickup head is kept constant by using a separate laser beam. This is very similar to every CD player that uses a "focus" laser to move the laser that reads digital bits to the proper spacing between the reader and the disc. Since phono records vary in thickness, this feature assures precision alignment from the pickup head to the record. The servos are fast and responsive allowing the LT to accommodate even warped records. Also the new audiophile 180 gram (thick) records are reproduced beautifully.
Now this took some time to completely flesh out. Where's my proof of patent papers?
