Detector for determining a position of at least one object

Patent metadata

Field	Value
Publication number	US-12488495-B2
Application number	US-202318543015-A
Country	US
Kind code	B2
Filing date	Dec 18, 2023
Priority date	Jan 9, 2019
Publication date	Dec 2, 2025
Grant date	Dec 2, 2025

Abstract

Described herein is a detector for determining a position of at least one object. The detector includes at least one sensor element having a matrix of optical sensors, the optical sensors each having a light-sensitive area, wherein the sensor element is configured to determine a reflection image of the object. The detector also includes an evaluation device configured to select a reflection feature of the reflection image, and determine a distance estimate of the selected reflection feature of the reflection image by optimizing at least one blurring function fa, wherein the distance estimate is given by a longitudinal coordinate z and an error interval±ε. The evaluation device is adapted to determine at least one displacement region in at least one reference image corresponding to the distance estimate, and to match the selected reflection feature with at least one reference feature within the displacement region.

First claim

The invention claimed is:

1 . A detector comprising:
at least one sensor element having a matrix of optical sensors, the optical sensors each having a light-sensitive area, wherein the sensor element is configured to determine at least one reflection image of the object; and at least one evaluation device, wherein the evaluation device is configured to select at least one reflection feature of the at least one reflection image, wherein the evaluation device is configured for determining at least one distance estimate of the selected at least one reflection feature of the at least one reflection image from a blurring function of the selected at least one reflection feature, wherein the evaluation device is adapted to determine at least one displacement region in at least one reference image corresponding to the at least one distance estimate, wherein the at least one displacement region is a region in the at least one reference image in which at least one reference feature corresponding to the selected at least one reflection feature is expected to be located in the at least one reference image, wherein the evaluation device is adapted to match the selected at least one reflection feature with at least one reference feature within the at least one displacement region.

2 . The detector according to claim 1 , wherein the at least one distance estimate is determined using at least one convolution-based algorithm including a depth-from-defocus algorithm.

3 . The detector according to claim 1 , wherein the at least one blurring function is optimized by varying the parameters of the at least one blurring function.

4 . The detector according to claim 3 , wherein the at least one reflection image is a blurred image i b , wherein the evaluation device is configured to reconstruct the longitudinal coordinate z from the blurred image i b and the at least one blurring function f a .

5 . The detector according to claim 4 , wherein the longitudinal coordinate z is determined by minimizing a difference between the blurred image i b and the convolution of the at least one blurring function f a with at least one further image i′ b ,
mini′b*fas(z)−ib,

by varying the parameters s of the at least one blurring function.

6 . The detector according to claim 1 , wherein the at least one blurring function f a is a function or composite function composed from at least one function from the group consisting of: a Gaussian, a sinc function, a pillbox function, a square function, a Lorentzian function, a radial function, a polynomial, a Hermite polynomial, a Zernike polynomial, and a Legendre polynomial.

7 . The detector according to claim 1 , wherein the evaluation device is adapted to determine a displacement of the matched at least one reference feature and the selected at least one reflection feature, wherein the evaluation device is adapted to determine a longitudinal information of the matched features using a predetermined relationship between a longitudinal coordinate and the displacement.

8 . The detector according to claim 1 , wherein the at least one reference image and the at least one reflection image are images of the object determined at different spatial positions having a fixed distance, wherein the evaluation device is adapted to determine an epipolar line in the at least one reference image, wherein the at least one displacement region extends along the epipolar line, wherein the evaluation device is adapted to determine the at least one reference feature along the epipolar line corresponding to the longitudinal coordinate z and to determine an extent of the at least one displacement region along the epipolar line corresponding to the error interval±ε.

9 . The detector according to claim 8 , wherein the evaluation device is configured to perform the following steps:
Determining the at least one displacement region for the image position of each reflection feature; Assigning an epipolar line to the at least one displacement region of each reflection feature by assigning the epipolar line closest to the at least one displacement region and/or within the at least one displacement region and/or closest to the at least one displacement region along a direction orthogonal to the epipolar line; and Assigning and/or determining at least one reference feature to each reflection feature such as by assigning the at least one reference feature closest to the assigned at least one displacement region and/or within the assigned at least one displacement region and/or closest to the assigned at least one displacement region along the assigned epipolar line and/or within the assigned at least one displacement region along the assigned epipolar line.

10 . The detector according to claim 1 , wherein the detector further comprises at least one illumination source, wherein the at least one illumination source is adapted to generate at least one illumination pattern for illumination of the object, wherein the at least one illumination pattern comprises at least one pattern selected from the group consisting of: at least one point pattern, in particular 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; and at least one line pattern comprising at least two lines such as parallel or crossing lines.

11 . The detector according to claim 10 , wherein the at least one illumination pattern comprises at least one hexagonal pattern, wherein the pattern is rotated relative to the baseline and/or wherein the hexagonal pattern is at least one displaced hexagonal pattern, wherein individual points of the hexagonal pattern are displaced by a random distance from the regular position.

12 . The detector according to claim 10 , wherein the sensor element is adapted to determine at least one reflection pattern, wherein the evaluation device is adapted to select at least one feature of the at least one reflection pattern and to determine the at least one distance estimate of the selected feature of the at least one reflection pattern by optimizing the at least one blurring function f a .

13 . The detector according to claim 12 , wherein the at least one reference image is an image of the at least one illumination pattern at an image plane at a position of the at least one illumination source, wherein the evaluation device is adapted to determine the at least one displacement region in the at least one reference image corresponding to the at least one distance estimate of the selected feature of the at least one reflection pattern, wherein the evaluation device is adapted to match the selected feature of the at least one reflection pattern with at least one feature of the reference pattern within the at least one displacement region.

14 . The detector according to claim 1 , wherein the detector comprises at least two sensor elements each having a matrix of optical sensors, where at least one first sensor element and at least one second sensor element are positioned at different spatial positions, wherein the evaluation device is adapted to select at least one image determined by the first sensor element or the second sensor element as at least one reflection image and to select at least one image determined by the other one of the first sensor element or the second sensor el

Assignees

• Trinamix Gmbh

Inventors

• Eberspach Michael
• Lennartz Christian
• Send Robert
• Schindler Patrick
• Schillen Peter
• Bruder Ingmar

Classifications

• G06T5/70

  Denoising; Smoothing · CPC title

• G06T7/74 Primary

  involving reference images or patches · CPC title

• G06T7/521 Primary

  from laser ranging, e.g. using interferometry; from the projection of structured light · CPC title

• G06T7/571

  from focus · CPC title

• G06T5/50

  using two or more images, e.g. averaging or subtraction · CPC title