Detector for determining a position of at least one object

Patent metadata

Field	Value
Publication number	US-11067692-B2
Application number	US-201816623557-A
Country	US
Kind code	B2
Filing date	Jun 25, 2018
Priority date	Jun 26, 2017
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

A method for adjusting a detector (110) for determining a position of at least one object (112) within a range of measurement (114) is disclosed. The detector (110) comprises at least two longitudinal optical sensors (116) and at least one transfer device (118) for imaging the object (112) into an image plane. The transfer device (118) has a focal plane. The transfer device (118) is positioned in between the longitudinal optical sensors (116) and the object (112). Each of the longitudinal optical sensors (116) has at least one sensor region (120). Each of the longitudinal optical sensors (116) is designed to generate at least one longitudinal sensor signal in a manner dependent on an illumination of the respective sensor region (120) by at least one light beam (178) propagating from the object (112) to the detector (110), wherein the longitudinal sensor signal, given the same total power of the illumination, is dependent on a beam cross-section of the light beam (178) in the sensor region (120). The detector (110) further comprises at least one evaluation device (124). The method comprises the following steps: (i) subsequently moving the object (112) longitudinally to at least two different calibration positions (134, 136) having at least two different longitudinal coordinates within the range of measurement (114); (ii) recording, for each of the calibration positions (134, 136), at least one first longitudinal sensor signal generated by a first longitudinal optical sensor (126) and at least one second longitudinal sensor signal generated by a second longitudinal optical sensor (128); (iii) forming, for each of the calibration positions (134, 126), at least one calibration signal using the first and second longitudinal sensor signals; (iv) generating a calibration function using the calibration signals, the calibration function defining a relationship between the longitudinal coordinate of the object (112) and the first and second longitudinal sensor signals.

First claim

The invention claimed is:

1. A method of adjusting a detector, wherein the detector is suitable for determining a position of at least one object within a range of measurement, wherein the detector constitutes a coordinate system in which an optical axis forms a z-axis, a direction parallel or antiparallel to the z-axis being a longitudinal direction, and a coordinate along the z-axis being a longitudinal coordinate, the detector comprising at least two longitudinal optical sensors and at least one transfer device suitable for imaging the at least one object into an image plane, the at least one transfer device having a focal plane and being positioned between the at least two longitudinal optical sensors and the at least one object, each of the at least two longitudinal optical sensors having at least one sensor region and being designed to generate at least one longitudinal sensor signal in a manner dependent on an illumination of the respective sensor region by at least one light beam propagating from the at least one object to the detector, wherein the at least one longitudinal sensor signal, given the same total power of the illumination, is dependent on a beam cross-section of the at least one light beam in the respective sensor region, the detector further comprising at least one evaluation device, the method comprising:
(i) subsequently moving the at least one object longitudinally to at least two different calibration positions having at least two different longitudinal coordinates within the range of measurement;
(ii) recording, for each of the at least two different calibration positions, at least one first longitudinal sensor signal generated by a first longitudinal optical sensor and at least one second longitudinal sensor signal generated by a second longitudinal optical sensor;
(iii) forming, for each of the at least two different calibration positions, at least one calibration signal using the at least one first longitudinal sensor signal and the at least one second longitudinal sensor signal; and
(iv) generating a calibration function using the at least one calibration signal, the calibration function defining a relationship between a longitudinal coordinate of the at least one object and the at least one first longitudinal sensor signal and the at least one second longitudinal sensor signal;
wherein the method further comprises at least one adjustment step for positioning the first longitudinal optical sensor and the second longitudinal optical sensor, the adjustment step comprising the following substeps:
a) positioning the object in at least one outermost position within the measurement range, the outermost position having a maximum longitudinal coordinate;
b) positioning the first longitudinal optical sensor at a longitudinal coordinate of a focused image plane;
c) positioning the object in at least one closest position within the measurement range, the closest position having a minimum longitudinal coordinate; and
d) positioning the second longitudinal optical sensor at a longitudinal coordinate of a focused image plane.

2. The method of claim 1 , further comprising making at least one measurement, wherein the longitudinal coordinate of the at least one object is determined by using the calibration function.

3. The method of claim 1 , wherein the at least one adjustment is performed before (i).

4. The method of claim 1 , further comprising (v) positioning, suitable for positioning the first longitudinal optical sensor and the second longitudinal optical sensor, the positioning comprising:
A) positioning the at least one object in at least one outermost position within the range of measurement, the at least one outermost position having a maximum longitudinal coordinate, and positioning the first longitudinal optical sensor at a longitudinal position between the at least one transfer device and the focal plane of the at least one transfer device; and
B) positioning the second longitudinal optical sensor at a longitudinal coordinate of a focused image plane.

5. The method of claim 4 , wherein A) comprises:
A1) defining a sensor threshold for the at least one first longitudinal sensor signal;
A2) moving the first longitudinal optical sensor towards the focal plane of the at least one transfer device and comparing the at least one first longitudinal sensor signal with the sensor threshold; and
A3) positioning the first longitudinal optical sensor at a position at which the at least one first longitudinal sensor signal equals the sensor threshold.

6. The method of claim 4 , wherein (v) is performed before (i).

7. A detector, suitable for determining a position of at least one object, wherein the detector constitutes a coordinate system in which an optical axis forms a z-axis, a direction parallel or antiparallel to the z-axis being a longitudinal direction, and a coordinate along the z-axis being a longitudinal coordinate, wherein the detector comprises:
at least one transfer device, suitable for imaging the at least one object into an image plane, and having a focal plane;
at least two longitudinal optical sensors, wherein each of the at least two longitudinal optical sensors has at least one sensor region and is designed to generate at least one longitudinal sensor signal in a manner dependent on an illumination of the respective sensor region by at least one light beam propagating from the at least one object to the detector, wherein the at least one longitudinal sensor signal, given the same total power of the illumination, is dependent on a beam cross-section of the at least one light beam in the respective sensor region; and
at least one evaluation device,
wherein the detector is adapted to move the at least one object subsequently to at least two different calibration positions having at least two different longitudinal coordinates within a range of measurement,
wherein the at least one evaluation device is adapted to record, for each of the at least two different calibration positions, at least one first longitudinal sensor signal generated by a first longitudinal optical sensor and at least one second longitudinal sensor signal generated by a second longitudinal optical sensor,
wherein the at least one evaluation device is adapted to form, for each of the at least two different calibration positions, at least one calibration signal using the at least one first longitudinal sensor signal and the at least one second longitudinal sensor signal, and
wherein the at least one evaluation device is designed to generate a calibration function using the at least one calibration signal, the calibration function defining a relationship between a longitudinal coordinate of the at least one object and the at least one first longitudinal sensor signal and the at least one second longitudinal sensor signal:
wherein the detector is adapted to perform at least one adjustment step for positioning the first longitudinal optical sensor and the second longitudinal optical sensor, the adjustment step comprising the following substeps:
a) positioning the object in at least one outermost position within the measurement range, the outermost position having a maximum longitudinal coordinate:
b) positioning the first longitudinal optical sensor at a longitudinal coordinate of a focused image plane;
c) positioning the object in at least one closest position within the measurement range, the closest position having a minimum longitudinal coordinate; and
d) positioning the second longitudinal optical sensor at a longitudinal coordinate of a focused image plane.

8. The detector of claim 7 , wherein the at least one evaluation device is designed to generate at least one item of information on a longitudinal position of the at least one objec

Assignees

• Trinamix Gmbh

Inventors

• Lungenschmied Christoph
• Pekkola Oili
• Schindler Patrick
• Send Robert
• Bruder Ingmar
• Thiel Erwin
• Irle Stephan

Classifications

• G01S7/481

  Constructional features, e.g. arrangements of optical elements · CPC title

• G01C3/32 Primary

  by focusing the object, e.g. on a ground glass screen · CPC title

• G01S17/42

  Simultaneous measurement of distance and other co-ordinates (indirect measurement G01S17/46) · CPC title

• G01S7/4816

  of receivers alone · CPC title

• G01S11/12

  using electromagnetic waves other than radio waves · CPC title