Abstract 1. AN INFORMATION RECORD ADAPTED FOR USE WITH A PLAYBACK STYLUS TO EFFECT OF SIGNALS OCCUPYING A BANDWIDTH OF AT LEAST SEVERAL MEGAHERTZ WHEN RELATIVE MOTION AT A DESIRED RATE IS ESTABLISHED BETWEEN SAID RECORD AND SAID STYLUS, SAID RECORD COMPRISING: (A) A DISC HAVING A SPIRAL GROOVE IN A SURFACE THEREOF, SAID GROOVE BEING DIMENSIONED FOR RECEPTION THEREIN OF SAID STYLUS AND CONTAINING AN INFORMATION TRACK CONSTITUTED BY GEOMETRIC VARIATIONS IN THE BOTTOM OF SAID GROOVE, (B) A CONTINOUS CONDUCTIVE METAL LAYER ON SAID SURFACE, SAID LAYER BEING OF SUBSTANTIALLY UNIFORM THICKNESS, AND (C) A THIN DIELECTRIC COATING OF UNIFORM THICKNESS OVERLYING SAID METAL LAYER, SAID DIELECTRIC COATING BEING A POLYSTYRENE APPLIED IN A GLOE DISCHARGE, AND THE COMBINED THICKNESS OF SAID CONDUCTIVE LAYER AND SAID DIELECTRIC COATING DO NOT FILL SAID GROOVE, ALLOWING FOR RECEPTION OF SAID STYLUS WITHIN SAID GROOVE DURING PLAYBACK.
AN INFORMATION RECORD ADAPTED FOR USE WITH A PLAYBACK STYLUS TO EFFECT OF SIGNALS OCCUPYING A BANDWIDTH OF AT LEAST SEVERAL MEGAHERTZ WHEN RELATIVE MOTION AT A DESIRED RATE IS ESTABLISHED BETWEEN SAID RECORD AND SAID STYLUS, SAID RECORD COMPRISING: (A) A DISC HAVING A SPIRAL GROOVE IN A SURFACE THEREOF, SAID GROOVE BEING DIMENSIONED FOR RECEPTION THEREIN OF SAID STYLUS AND CONTAINING AN INFORMATION TRACK CONSTITUTED BY GEOMETRIC VARIATIONS IN THE BOTTOM OF SAID GROOVE, (B) A CONTINOUS CONDUCTIVE METAL LAYER ON SAID SURFACE, SAID LAYER BEING OF SUBSTANTIALLY UNIFORM THICKNESS, AND (C) A THIN DIELECTRIC COATING OF UNIFORM THICKNESS OVERLYING SAID METAL LAYER, SAID DIELECTRIC COATING BEING A POLYSTYRENE APPLIED IN A GLOE DISCHARGE, AND THE COMBINED THICKNESS OF SAID CONDUCTIVE LAYER AND SAID DIELECTRIC COATING DO NOT FILL SAID GROOVE, ALLOWING FOR RECEPTION OF SAID STYLUS WITHIN SAID GROOVE DURING PLAYBACK.
Claim 2
Dependent Claim
144 words
AN INFORMATION RECORD ADAPTED FOR USE WITH A PLAYBACK STYLUS TO EFFECT OF SIGNALS OCCUPYING A BANDWIDTH OF AT LEAST SEVERAL MEGAHERTZ WHEN RELATIVE MOTION AT A DESIRED RATE IS ESTABLISHED BETWEEN SAID RECORD AND SAID STYLUS, SAID RECORD COMPRISING: (A) A DISC HAVING A SPIRAL GROOVE IN A SURFACE THEREOF, SAID GROOVE BEING DIMENSIONED FOR RECEPTION THEREIN OF SAID STYLUS AND CONTAINING AN INFORMATION TRACK CONSTITUTED BY GEOMETRIC VARIATIONS IN THE BOTTOM OF SAID GROOVE, (B) A CONTINOUS CONDUCTIVE METAL LAYER ON SAID SURFACE, SAID LAYER BEING OF SUBSTANTIALLY UNIFORM THICKNESS, AND (C) A THIN DIELECTRIC COATING OF UNIFORM THICKNESS OVERLYING SAID METAL LAYER, SAID DIELECTRIC COATING BEING A POLYSTYRENE APPLIED IN A GLOE DISCHARGE, AND THE COMBINED THICKNESS OF SAID CONDUCTIVE LAYER AND SAID DIELECTRIC COATING DO NOT FILL SAID GROOVE, ALLOWING FOR RECEPTION OF SAID STYLUS WITHIN SAID GROOVE DURING PLAYBACK.