Patent ID: 7042811

Claim:
A laser heterodyne interferometer based system for playing an audio recording physically stored in a groove formed in a cylinder, said system comprising: a. an optical system for generating a reference beam and a signal beam, comprising: i. a light source for generating a beam of light; ii. a first beam splitter for dividing said beam of light into said reference and signal beams; iii. a first transmission path along which said signal beam travels from said first beam splitter to said cylinder, whereby at the conclusion of said first transmission path said signal beam impinges upon and is reflected by said groove formed in said cylinder; iv. a second transmission path along which said reference beam travels; v. a frequency shifter positioned in said second transmission path, whereby said reference signal passes through said frequency shifter as it travels along said second transmission path; and vi. a third transmission path along which said signal beam travels after having been reflected by said impinged upon groove; vii. a detector for receiving said reference beam and said signal beam at the conclusion of said second and third transmission paths, respectively; and viii. means for outputting said audio recording to an audio speaker or audio recorder; b. an optics platform upon which said optical system is statically mounted; and c. an audio platform upon which said cylinder is movably mounted relative to said optics platform.