mardi 10 juin 2014

Evolution of wearable devices through patent drawings

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By June 2, 2014, 2:21 PM PST

Hearing aid patent from 1939

One of the most successful categories of electronic wearable devices is one that most people never think of - hearing aids. This patent was filed in 1939 and features a wearable bone-conduction hearing aid.
U.S. Patent number: 2249572
Filed: March 22, 1939, Publication date: July 15, 1941
Assignee: Dora Lieber, Lieber Patents Corp.

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