US 12,264,970 B2
Method, device, and system for temperature calibration and determination of a temperature in a scene
Thomas Winzell, Lund (SE); and Anthony Hawkins, Lund (SE)
Assigned to AXIS AB, Lund (SE)
Filed by Axis AB, Lund (SE)
Filed on Mar. 5, 2021, as Appl. No. 17/192,927.
Claims priority of application No. 20164801 (EP), filed on Mar. 23, 2020.
Prior Publication US 2021/0293626 A1, Sep. 23, 2021
Int. Cl. G01J 5/00 (2022.01); G01J 5/02 (2022.01); G01J 5/06 (2022.01); G01J 5/80 (2022.01)
CPC G01J 5/007 (2013.01) [G01J 5/02 (2013.01); G01J 2005/0077 (2013.01); G01J 2005/0092 (2013.01); G01J 5/064 (2022.01); G01J 5/80 (2022.01)] 14 Claims
OG exemplary drawing
 
1. A method for temperature calibration of a thermal camera configured to be arranged at a scene and for determination of a temperature in the scene, wherein the method comprises:
at each time point of a plurality of time points in a first period of time, collecting an ambient temperature representing a temperature at a first part of the scene to obtain collected ambient temperatures spanning over a range of ambient temperatures, and, by means of the thermal camera, collecting one or more thermal image sensor signal values corresponding to each of the collected ambient temperatures and relating to the first part of the scene so as to generate a plurality of thermal image sensor signal values,
wherein the first part of the scene comprises one or more background areas for which the one or more thermal sensor signal values are collected; and
determining a calibration function as a function fitting the collected plurality of ambient temperatures and the plurality of thermal image sensor signal values,
wherein the calibration function gives temperature as a function of thermal image sensor value; and
in a second period of time,
by means of the thermal camera, capturing a thermal image of the scene comprising thermal image sensor signal values relating to a second part of the scene; and
determining a temperature at the second part of the scene based on the calibration function and based on one or more of the thermal image sensor signal values comprised in the captured thermal image of the scene and relating to the second part of the scene.