US 12,213,765 B2
Photodetector calibration of an optical measurement system
Sebastian Sorgenfrei, Playa Vista, CA (US); Ryan Field, Culver City, CA (US); Bruno Do Valle, Brighton, MA (US); Isai Olvera, South Portland, ME (US); Jacob Dahle, Arlington, MA (US); and Husam Katnani, Braintree, MA (US)
Assigned to HI LLC, Culver City, CA (US)
Filed by HI LLC, Los Angeles, CA (US)
Filed on Nov. 30, 2023, as Appl. No. 18/524,743.
Application 18/524,743 is a continuation of application No. 17/202,668, filed on Mar. 16, 2021, granted, now 11,903,676.
Claims priority of provisional application 63/070,123, filed on Aug. 25, 2020.
Claims priority of provisional application 62/992,536, filed on Mar. 20, 2020.
Prior Publication US 2024/0099587 A1, Mar. 28, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. A61B 5/00 (2006.01)
CPC A61B 5/0082 (2013.01) [A61B 5/4064 (2013.01); A61B 5/6803 (2013.01); A61B 5/7217 (2013.01); A61B 2560/0223 (2013.01); A61B 2560/0443 (2013.01); A61B 2562/046 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An optical measurement system comprising:
a light source configured to emit light directed at a target;
an array of photodetectors configured to detect photons of the light after the light is scattered by the target; and
a processing unit configured to:
measure a noise level of a photodetector included in the array of photodetectors, the noise level comprising a dark count rate that measures a dark count divided by a time period;
determine that the noise level meets a predetermined threshold comprising a dark count rate threshold; and
prevent, based on the determining that the noise level meets the predetermined threshold, an output of the photodetector from being used in generating a histogram based on a temporal distribution of photons detected by the array of photodetectors, the preventing comprising switching the output to a monitoring circuit that monitors a characteristic of the optical measurement system separate from the photodetector.