US 11,723,564 B1
Optical sensor light filtering in a wearable device
Miro Yakov Shverdin, Mountain View, CA (US); and Nevzat Akin Kestelli, San Jose, CA (US)
Assigned to AMAZON TECHNOLOGIES, INC., Seattle, WA (US)
Filed by AMAZON TECHNOLOGIES, INC., Seattle, WA (US)
Filed on Feb. 1, 2021, as Appl. No. 17/164,353.
Int. Cl. A61B 5/1455 (2006.01); A61B 5/0205 (2006.01); A61B 5/00 (2006.01); G01J 3/51 (2006.01); A61B 5/024 (2006.01); A61B 5/332 (2021.01)
CPC A61B 5/14552 (2013.01) [A61B 5/0205 (2013.01); A61B 5/7278 (2013.01); G01J 3/51 (2013.01); A61B 5/02433 (2013.01); A61B 5/332 (2021.01); A61B 5/681 (2013.01); A61B 2562/0238 (2013.01); A61B 2562/043 (2013.01); A61B 2562/185 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A wearable device comprising:
a support structure that retains the wearable device proximate to a user;
a light source;
a photodiode comprising a light-sensitive area;
a first filter that is at a first distance from the light source, wherein the first filter:
allows a first color of light to be received at a first portion of the light-sensitive area, and
blocks a second color of light from being received at the first portion of the light-sensitive area;
a second filter that is at a second distance from the light source, wherein the second filter:
allows the second color of light to be received at a second portion of the light-sensitive area, and
blocks the first color of light from being received at the second portion of the light-sensitive area;
one or more memories storing computer-executable instructions; and
one or more processors, wherein the one or more processors execute the computer-executable instructions to:
operate, at a first time, the light source to generate the first color of light;
determine, based on the first color of light received at the photodiode through the first filter, first data indicative of an intensity of the first color of light at the first time;
operate, at a second time, the light source to generate the second color of light;
determine, based on the second color of light received at the photodiode through the second filter, second data indicative of an intensity of the second color of light at the second time;
determine, based on the first data, a heart rate of the user; and
determine, based on the second data, a blood oxygen level of the user.