US 12,455,207 B2
Method for detecting test gas exiting a test body using an optical sensor
Daniel Wetzig, Cologne (DE)
Assigned to Inficon GMBH, Cologne (DE)
Appl. No. 18/270,109
Filed by INFICON GMBH, Cologne (DE)
PCT Filed Dec. 29, 2021, PCT No. PCT/EP2021/087812
§ 371(c)(1), (2) Date Jun. 28, 2023,
PCT Pub. No. WO2022/152564, PCT Pub. Date Jul. 21, 2022.
Claims priority of application No. 102021100405.5 (DE), filed on Jan. 12, 2021.
Prior Publication US 2024/0068901 A1, Feb. 29, 2024
Int. Cl. G01M 3/20 (2006.01); G01M 3/00 (2006.01)
CPC G01M 3/20 (2013.01) [G01M 3/002 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A method for detecting a test gas cloud escaping from a leak in a test specimen, comprising the following steps:
receiving optical radiation reflected or emitted from the test specimen or its background at a first point in time with an optical sensor configured to detect at least one wavelength or a wavelength range of an optical absorption spectrum of the test gas cloud,
creating a first digital image from the optical radiation received at the first point in time such that signal amplitudes of first digital image points xij correspond to the amplitude of at least one absorption wavelength range of the test gas cloud,
receiving optical radiation reflected or emitted from the test specimen or its background at a second point in time by means of the optical sensor,
emitting a gas shock to move the gas cloud in a direction from which the image section is captured;
creating a second digital image from the optical radiation received at the second point in time such that the signal amplitudes of second digital image points xij correspond to the amplitude of at least one absorption wavelength range of the test gas cloud,
comparing the first digital image with at least one second digital image of the reflected optical radiation, which is different from the first image,
wherein a leak is considered detected when at least the difference of the amplitude of at least a first digital image point xij of the first digital image and the amplitude of at least a second digital image point xij of the second digital image exceeds a threshold value,
wherein
i, j are each natural numbers
xij the first digital image point at column i and row j of the first digital image, and
xij the second digital image point column i and row j of the second digital image.