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Comment by pjc50

4 months ago

The patent: https://patents.google.com/patent/US10517484B2/en

Note how similar this is to the pulse oximeter, which was invented in Japan in 1972 and patented in the US in 2004.

https://www.nihonkohden.com/technology/aoyagi.html

https://patents.google.com/patent/US20050049469A1/en

> Note how similar this is to the pulse oximeter, which was invented in Japan in 1972 and patented in the US in 2004.

How could an invention from 1972, which I assume was publically disclosed around that time, be patented in 2004?

Were the details kept secret for 32 years?