The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 28, 1995
Filed:
May. 17, 1994
Salim N Jabr, Mountain View, CA (US);
Other;
Abstract
Digital information is represented by surface steps orthogonal to the surface of a record carrier, said steps having a plurality of values between one tenth and 10,000 nanometers. The steps are read out by an optical differential interference method that is capable of resolving one tenth of a nanometer. The steps are written by a repeated masking and etching technique to form a master record carrier on glass from which a stamper is formed by molding and used to stamp replicate record carriers in polymeric material. In a different embodiment of the record carrier the surface steps are created by a modulated laser beam that ablates an integral number of layers from a pre-coated multilayer structure. In a third embodiment the data is represented by modulating the index of refraction between spots on a thin material film. The index difference is written optically. An extension to multiple thin film layers is also disclosed. An optically writeable embodiment of the invention is presented wherein the surface steps are produced by ablating a surface, utilising optical energy pulses.