Optoelectronic sensor and method of detecting objects in a monitored zone

Patent metadata

Field	Value
Publication number	US-10436935-B2
Application number	US-201816053928-A
Country	US
Kind code	B2
Filing date	Aug 3, 2018
Priority date	Aug 4, 2017
Publication date	Oct 8, 2019
Grant date	Oct 8, 2019

Abstract

An optoelectronic sensor for detecting objects in a monitored zone is provided that has a light transmitter having a plurality of individual light sources and a transmission optics arranged in front of the light transmitter for transmitting a transmitted light beam that is composed of a plurality of individual light beams of the individual light sources; a light receiver for generating a received signal from the transmitted light beam remitted in the monitored zone and incident on the light receiver; and an evaluation unit for detecting the objects from the received signal. An optical deflection element is arranged between the light transmitter and the transmission optics and has microoptical zones which are associated with the individual light sources and which deflect the individual light beams onto one another such that the cross-sections of the individual light beams together take up a smaller area in a virtual image plane in front of the transmission optics than the individual light sources themselves.

First claim

The invention claimed is:

1. An optoelectronic sensor for detecting objects in a monitored zone, the optoelectronic sensor comprising:
a light transmitter having a plurality of individual light sources and a transmission optics arranged in front of the light transmitter for transmitting a transmitted light beam that is composed of a plurality of individual light beams of the individual light sources;
a light receiver for generating a received signal from the transmitted light beam remitted in the monitored zone and incident on the light receiver;
an evaluation unit for detecting the objects from the received signal, and
an optical deflection element that is arranged between the light transmitter and the transmission optics and that has microoptical zones, the microoptical zones being associated with the individual light sources and the microoptical zones deflecting the individual light beams onto one another such that the cross-sections of the individual light beams together take up a smaller area in a virtual image plane in front of the transmission optics than the individual light sources themselves.

2. The sensor in accordance with claim 1 , wherein the microoptical zones are non-imaging microoptical zones.

3. The sensor in accordance with claim 1 ,
wherein the light transmitter has a VCSEL having a plurality of light emission surfaces as individual light sources.

4. The sensor in accordance with claim 1 ,
wherein at least a portion of the individual light sources are arranged on a circle.

5. The sensor in accordance with claim 4 ,
wherein the portion of the individual light sources forms a regular n-gon.

6. The sensor in accordance with claim 4 ,
wherein individual light sources that are not arranged on the circle are arranged at the center of the circle.

7. The sensor in accordance with claim 1 ,
wherein the microoptical zones have light waveguides.

8. The sensor in accordance with claim 1 ,
wherein the microoptical zones have planar surfaces tilted with respect to the optical axis of the associated individual light source.

9. The sensor in accordance with claim 8 ,
wherein the planar surfaces form the side surfaces of a pyramid or of a truncated pyramid.

10. The sensor in accordance with claim 1 ,
wherein the optical deflection element has a hollow cone or a hollow truncated cone whose jacket surface forms microoptical zones.

11. The sensor in accordance with claim 1 ,
wherein the evaluation unit is configured to determine a distance of the remitted object from a time of flight of the transmitted light beams transmitted and received again or by means of triangulation.

12. The sensor in accordance with claim 1 ,
that is configured as a laser scanner and that has a movable deflection unit to periodically deflect the transmitted light beam in the monitored zone.

13. A method of detecting objects in a monitored zone, the method comprising the steps of:
transmitting a transmitted light beam that is composed of a plurality of individual light beams by a transmission optics;
generating a received signal from the transmitted light beam remitted in the monitored zone;
deflecting the individual light beams toward one another with the aid of microoptical zones before the entry into the transmission optics such that the cross-sections of the individual light beams together take up a smaller area in a virtual image plane in front of the transmission optics than during their generation and
evaluating the received signal to detect the objects.

14. The method according to claim 13 ,
wherein the microoptical zones are non-imaging microoptical zones.

Assignees

• Sick Ag

Inventors

• Gimpel Hartmut
• Tschuch Sebastian

Classifications

• G01S17/04

  Systems determining the presence of a target · CPC title

• H01S5/0071

  for beam steering, e.g. using a mirror outside the cavity to change the beam direction · CPC title

• G01S17/48

  Active triangulation systems, i.e. using the transmission and reflection of electromagnetic waves other than radio waves · CPC title

• G01S17/42 Primary

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

• H01S5/183

  having only vertical cavities, e.g. vertical cavity surface-emitting lasers [VCSEL] · CPC title