Thermal imaging camera for taking thermographic images

• US 8,476,590 B2
• Filed: 12/14/2012
• Issued: 07/02/2013
• Est. Priority Date: 12/12/2008
• Status: Active Grant

• Current Assignee: Testo AG
• Original Assignee: Testo AG
• Inventors: Stratmann, Martin, Messerschmid, Andreas, Zahn, Patrick, Schmieder, Matthias
• Primary Examiner(s): Kim, Kiho
• Application Number:
  US13/715,275
• Publication Number:
  US 20130135480A1
• Time in Patent Office: 200 Days
• Field of Search: 250/330, 250/334
• US Class Current: 250/330
• CPC Class Codes: G01J 2005/0077 Imaging
• CPC Class Codes: H04N 23/11 for generating image signals from visible and infrared light wavelengths
• CPC Class Codes: H04N 23/63 by using electronic viewfinders
• CPC Class Codes: H04N 23/69 Control of means for changing angle of the field of view, e.g. optical zoom objectives or electronic zooming
• CPC Class Codes: H04N 23/698 for achieving an enlarged field of view, e.g. panoramic image capture
• CPC Class Codes: H04N 5/33 Transforming infrared radiation cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20

Abstract

In a thermal imaging camera for acquisition of thermographic images of a measurement object, an electronic evaluation unit is integrated into the thermal imaging camera; it is designed for recognition of corresponding partial regions of the acquired thermographic images, and with it, the acquired images can be assembled into an overall image by overlapping the corresponding partial regions and displayed. The acquisition of the images preferably takes place during the swiveling of the thermal imaging camera over the solid angle region of the desired overall image.

Claims

1. A thermal imaging camera for taking thermographic images of a measurement object in the infrared region, with a display tool built in or on the housing for a representation of the acquired thermographic images, where the thermal imaging camera is made as a hand-held unit configured to acquire thermographic images with a swiveling motion of the thermographic camera, said thermal imaging camera comprising an electronic evaluation unit configured to stitch at least one acquired thermographic image with another thermographic image, where the images each repeat a same image region of the measurement object, said thermographic images being stitched about said same image regions to form a thermographic overall image that can be displayed with the display tool, with correction being made for the swiveling motion of the thermal imaging camera by assembling the acquired thermographic images using a set of undistorted stripes configured to limit distortion of the acquired thermographic images, where the display tool has a zoom function for free selection of an image segment of the overall image that is to be magnified.

2. A thermal imaging camera as in claim 1, characterized by the fact that the evaluation unit contains an image recognition tool with which partial regions with the same image regions can be identified when there is a number of acquired thermographic images.

3. A thermal imaging camera as in claim 2, characterized by the fact that the same image region may extend horizontally.

4. A thermal imaging camera as in claim 3, characterized by the fact that the same image region may extend vertically.

5. A thermal imaging camera as in claim 2, characterized by the fact that the same image region may extend vertically.

6. A thermal imaging camera as in claim 1, characterized by the fact that the evaluation unit has a tool for pattern and/or feature recognition.

7. A thermal imaging camera as in claim 1, characterized by the fact that the thermal imaging camera includes a trigger configured such that through the actuation of which a thermographic image can be taken.

8. A thermal imaging camera as in claim 1, characterized by the fact that the scale of magnification of the display tool is automatically adjusted to the size of the current overall image.

9. A thermal imaging camera as in claim 1, characterized by the fact that a representation of the thermographic image acquired in the infrared spectral region and an image acquired in the visible spectral region can be represented at the same time by the display tool.

10. A thermal imaging camera as in claim 9, characterized by the fact that the thermographic image and the image acquired in the visible spectral region can be represented at least partially covering one another and/or α

-blended, so that image segments of the same parts of the measurement object that correspond to each other can be represented at the same point on the display tool and/or in the same display scale.

11. A thermal imaging camera as in claim 1, characterized by the fact that the boundary of an already acquired thermographic image, and a currently acquirable thermographic image can be represented on the display tool by means of a switchable labeling.

12. A thermal imaging camera as in claim 1, characterized by the fact that the segment of the measurement object acquired in the visible spectral region is larger than the segment of the measurement object acquired with an individual and/or with the assembled thermographic image.

13. A thermal imaging camera as in claim 1, characterized by the fact that the acquisition of the thermographic images takes place by means of an uncooled sensor field.

14. A thermal imaging camera as in claim 1, characterized by the fact that at least one motion sensor, with which the swiveling motion of the thermal imaging camera can be detected, is integrated into the thermal imaging camera.

15. A thermal imaging camera as in claim 14, characterized by the fact that the sensor signals of the motion sensor can be detected and evaluated by the evaluation unit.

16. A thermal imaging camera as in claim 1, characterized by the fact that the resolution of the detector field of the thermal imaging camera is smaller than the resolution of the display tool.

17. A thermal imaging camera as in claim 1, characterized by the fact that the acquisition of the thermographic images and the construction of the overall image takes place in real time during the swiveling motion of the thermal imaging camera.

18. A thermal imaging camera as in claim 1, characterized by the fact that the overall image is appropriately updated when an additional thermographic image is acquired by adding the additionally acquired image.

19. A thermal imaging camera as in claim 1, characterized by the fact that the resolution of the thermographic camera can be preset for each acquisition of thermographic image.

20. A thermal imaging camera as in claim 1, wherein the evaluation unit is configured to identify regions of the acquired thermographic images requiring correction for optical distortion.