Patent comparison

Compare Patents

Compare two patents side by side. Add ?a=us/7657849&b=us/8046721 to the URL to load specific patents.

US 3501586

How James Russell Invented the Digital Optical Disc

A 1966 invention that replaced physical needles on vinyl records with a laser beam reading digital data from a spinning disc.

Statusexpired

Granted1970

Expires1986

Claims0

Forward citations52

Prior art7

AssigneeBattelle Development Corp

InventorsJames T Russell

Patent B

Add ?b=us/7657849 to compare

How to use

Bookmark a comparison URL to save it. Format: /compare?a=[country]/[number]&b=[country]/[number]. Example: /compare?a=us/7657849&b=us/8046721