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US 2189285

How the View-Master 3D Image Viewer Works

A 1939 invention for a handheld device that uses two offset images to create the illusion of depth, famously known as the View-Master.

Statusexpired

Granted1940

Expires1959

Claims0

Forward citations28

Prior art0

AssigneeIndividual

InventorsWilhelm B Gruber

Patent B

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