Detector for identifying at least one material property

Patent metadata

Field	Value
Publication number	US-12332352-B2
Application number	US-202418743352-A
Country	US
Kind code	B2
Filing date	Jun 14, 2024
Priority date	Mar 15, 2019
Publication date	Jun 17, 2025
Grant date	Jun 17, 2025

Abstract

Described herein is a detector for identifying at least one material property m. The detector includes at least one sensor element including a matrix of optical sensors, the optical sensors each having a light-sensitive area. The sensor element is configured for recording at least one reflection image of a light beam originating from at least one object. The detector includes at least one evaluation device configured for determining the material property m by evaluation of at least one beam profile of the reflection image and evaluation of a material feature φ2m.

First claim

The invention claimed is:

1. A detector for identifying at least one material property m comprising
at least one light projector, wherein the light projector is configured for generating at least one illumination pattern for illumination of the object, wherein the illumination pattern comprises at least one pattern selected from the group consisting of: at least one point pattern; a pseudo-random point pattern; a random point pattern or a quasi-random pattern; at least one Sobol pattern; at least one quasiperiodic pattern; at least one pattern comprising at least one pre-known feature; at least one regular pattern; at least one triangular pattern; at least one hexagonal pattern; at least one rectangular pattern; at least one pattern comprising convex uniform tilings; at least one line pattern comprising at least one line;
at least one line pattern comprising at least two lines; and at least one line pattern comprising parallel or crossing lines;
at least one camera comprising a matrix of optical sensors, the optical sensors each having a light-sensitive area, wherein the camera is configured for recording at least one reflection image of a light beam originating from at least one object; and
at least one processor configured for determining the material property by evaluation of at least one beam profile of the reflection image,
wherein the processor is configured for determining at least one material feature φ2m by applying at least one material dependent image filter Φ2 to the reflection image, wherein the material dependent image filter is at least one filter selected from the group consisting of: a luminance filter; a spot shape filter; a grey-level-occurrence-based contrast filter; a grey-level-occurrence-based energy filter; a grey-level-occurrence-based homogeneity filter; a grey-level-occurrence-based dissimilarity filter; a Law's energy filter; a threshold area filter; and a linear combination thereof;
wherein the processor is configured for determining the material property m by evaluating the material feature φ2m.

2. The detector according claim 1 , wherein the material dependent image filter is a spot shape filter.

3. The detector according to claim 1 , wherein the material dependent image filter is Law's energy filter.

4. The detector according to claim 1 , wherein the at least one material property is a property selected from the group consisting of: a scattering coefficient, a translucency, a transparency, and a deviation from a Lambertian surface reflection.

5. The detector according to claim 1 , wherein the processor is configured for determining at least one distance feature φ1z by applying at least one distance dependent image filter Φ1 to the reflection image, and
wherein the processor is configured for determining a longitudinal coordinate z by evaluating the distance feature φ1z.

6. The detector according to claim 5 , wherein the distance dependent image filter is a structured-light-filter.

7. The detector according to claim 1 , wherein the camera comprises at least one CMOS sensor.

8. The detector according to claim 7 , wherein the CMOS sensor comprises at least 100000 optical sensors.

9. The detector according to claim 8 , wherein the CMOS sensor is sensitive in the range of 700 nm to 1000 nm.

10. The detector according to claim 1 , wherein the light projector comprises at least one laser source and at least one diffractive optical element.

11. The detector according to claim 10 , wherein the light projector is configured for generating at least one random point pattern or a quasi-random pattern for illumination of the object.

12. The detector according to claim 11 , wherein the light projector emits light having a wavelength of 700 nm to 1000 nm.

13. The detector according to claim 12 , wherein the light projector comprises at least one vertical cavity surface-emitting laser.

14. The detector according to claim 13 , wherein the light projector is integrated into a smartphone.

15. The detector according to claim 1 , wherein the light projector emits light having a wavelength of 700 nm to 1000 nm.

16. The detector according to claim 15 , wherein the light projector is configured for generating at least one random point pattern or a quasi-random pattern for illumination of the object.

17. The detector according to claim 1 , wherein the light projector is integrated into a smartphone.

18. The detector according to claim 17 , wherein the light projector and the optical sensors is arranged in a common plane.

19. The detector according to claim 18 , wherein the light projector emits light having a wavelength of 700 nm to 1000 nm.

20. The detector according to claim 1 , wherein the object is a human.

21. The detector according to claim 1 , wherein the detector is configured for identification and/or classification of the material.

22. The detector according to claim 20 , wherein the detector is configured for determining and/or validating whether a surface to be examined is or comprises human skin.

23. The detector according to claim 1 , wherein the detector is configured for detection of human skin.

24. The detector according to claim 23 , wherein the at least one material property is a property selected from the group consisting of: a scattering coefficient, a translucency, a transparency, and a deviation from a Lambertian surface reflection.

25. The detector according to claim 1 , wherein the processor is configured for performing at least one image analysis and/or image processing in order to identify a reflection feature in the reflection image.

26. The detector according to claim 25 , wherein the processor is adapted to identify at least one reference feature in the reference image having an essentially identical longitudinal coordinate as the selected reflection feature.

27. The detector according to claim 25 , wherein the processor is adapted to determine at least one reference feature in at least one reference image corresponding to the at least one reflection feature.

28. The detector according to claim 25 , wherein the image analysis and/or image processing comprises selection of at least one region of interest.

29. The detector according to claim 25 , wherein the image analysis and/or image processing comprises a background correction.

30. The detector according to claim 25 , wherein the image analysis and/or image processing comprises applying a principle curvature-based region detector.

Assignees

• Trinamix Gmbh

Inventors

• Schick Friedrich
• Schillen Peter
• Schindler Patrick
• Schmidt Andre
• Eberspach Michael
• Lennartz Christian
• Send Robert
• Diesselberg Lars
• Hengen Heiko
• Bruder Ingmar
• Unger Jakob
• Bonsignore Christian

Classifications

• H04N23/74

  by influencing the scene brightness using illuminating means · CPC title

• H04N23/56

  provided with illuminating means · CPC title

• G06V20/95

  Pattern authentication; Markers therefor; Forgery detection · CPC title

• G06V10/764

  using classification, e.g. of video objects · CPC title

• G06V10/60

  relating to illumination properties, e.g. using a reflectance or lighting model · CPC title