Spatially resolving range-finding system

• US 20020003617A1
• Filed: 08/31/2001
• Published: 01/10/2002
• Est. Priority Date: 03/18/1999
• Status: Active Grant

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Mengel, Peter, Doemens, Guenter
• Granted Patent: US 6,636,300 B2
• Time in Patent Office: Days
• US Class Current: 356/4.01
• CPC Class Codes: G01S 17/89 for mapping or imaging
• CPC Class Codes: G01S 7/481 Constructional features, e.g. arrangements of optical elements
• CPC Class Codes: G01S 7/4814 of transmitters alone

Abstract

The principle of the invention is based on the combination of the following elements: an object 7 is illuminated in a pixelwise fashion by illuminating beams 5 emanating from light sources 1, imaging beams 6 striking receiving elements 2. The arrangement of the light sources 1 and the receiving elements 2 is corresponding, and the pixel access in the solid state image sensor is optional. The light sources 1 are driven serially, limits of laser protection regulations thereby being reliably complied with. An advantage is a substantially better signal quality at the receiving elements 2.

Claims

1. A spatially resolving range-finding system with the aid of which light travel time measurements can be carried out in a pixelwise fashion, comprising:

a one- or two-dimensional arrangement of modulable light sources;

a solid state image converter with receiving elements which exhibit a correspondence to the light sources with reference to the arrangement;

an optical system for guiding illuminating beams and imaging beams between light sources which can be driven serially, individually or in groups, object points corresponding thereto, and receiving elements driven correspondingly with the light sources it being possible to determine the range from each object point to the corresponding receiving element of the solid state image converter with the aid of a light travel time measurement.

2. The spatially resolving range-finding system according to claim 1, in which the correspondence between the arrangements of the light sources and the receiving elements is given by the use of a divider mirror and an optical system.

3. The spatially resolving range-finding system according to claim 1, in which, in the case of relatively large ranges between an object and the range-finding system, the arrangements of the light sources and the receiving elements are positioned immediately next to one another and their front is aligned in the direction of the object.

4. The spatially resolving range-finding system according to claim 1, in which the light sources can be driven optionally, and the corresponding receiving elements can be read out optionally.

5. The spatially resolving range-finding system according to claim 1, in which an optical system in the beam path of the illuminating beam and the imaging beam is designed in such a way that either one light source corresponds to one receiving element several light sources correspond to one receiving element or one light source corresponds to several receiving elements.

6. The spatially resolving range-finding system according to claim 1, in which the division is the same within the arrangements of the light sources and the receiving elements.

7. The spatially resolving range-finding system according to claim 1, in which the arrangement of the light sources and the arrangement of the receiving elements are represented in the form of a rectangular matrix in each case.

8. The spatially resolving range-finding system according to claim 1, in which the arrangement of the light sources and the arrangement of the receiving elements are designed in a fashion matched to the task.

9. The spatially resolving range-finding system according to claim 8, in which the arrangement of the light sources and the arrangement of the receiving elements are represented by a line, a full circle, a semicircle or cross.

10. The spatially resolving range-finding system according to claim 1, in which a sectional view or a three-dimensional image of an object is generated.

11. The spatially resolving range-finding system according to claim 1, in which the light sources are represented by rapidly modulable laser diodes or light-emitting diodes.

12. The spatially resolving range-finding system according to claim 1, in which the solid state image converter is represented by CMOS image converter.

13. The spatially resolving range-finding system according to claim 1, in which the light travel time measurement is a pulse travel time measurement or a phase measurement.

14. The spatially resolving range-finding system according to claim 1, for the purpose of intelligent building entrance safeguarding, railroad platform surveillance, railroad grid crossing surveillance or vehicle surveillance.

15. The spatially resolving range-finding system according to claim 1, for the purpose of surveillance of interiors of buildings or vehicles.