SYSTEMS AND METHODS FOR SAFE LASER IMAGING, DETECTION AND RANGING (LIDAR) OPERATION

• US 20090273770A1
• Filed: 04/30/2008
• Published: 11/05/2009
• Est. Priority Date: 04/30/2008
• Status: Abandoned Application

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Fritz, Bernard S., Krafthefer, Brian C., Bauhahn, Paul E.
• Application Number:
  US12/112,517
• Publication Number:
  US 20090273770A1
• Time in Patent Office: Days
• US Class Current: 356/5.10
• CPC Class Codes: G01C 3/08 Use of electric radiation detectors
• CPC Class Codes: G01S 17/10 using transmission of interrupted, pulse-modulated waves determination of distance by phase measurements G01S17/32
• CPC Class Codes: G01S 17/86 Combinations of lidar systems with systems other than lidar, radar or sonar, e.g. with direction finders
• CPC Class Codes: G01S 7/4802 using analysis of echo signal for target characterisation; Target signature; Target cross-section
• CPC Class Codes: G01S 7/497 Means for monitoring or calibrating

Abstract

A Laser Imaging, Detection and Ranging (LIDAR) system that automatically adjusts laser output so that no eye damage occurs to human targets. In one example, a component automatically measures range to targets in a field of view and determines the closest targets based on the measured range. A laser device outputs a laser beam and a controller adjusts one of pulse repetition frequency, power, or pulse duration of the laser device based on the measured range of the closest target in order to comply with a predefined eye safety model.

Claims

1. A method for controlling output of a Laser Imaging, Detection and Ranging (LIDAR) system, the method comprising:

automatically measuring range to one or more targets in a field of view;

determining the closest one of the targets based on the measured range; and

adjusting at least one of pulse repetition frequency, pulse amplitude, power, pulse duration, or optical intensity of a laser device based on the measured range of the closest target in order to comply with predefined human tissue safety model.

2. The method of claim 1, wherein the human tissue safety model includes at least one of an eye safety model or a skin safety model.

3. The method of claim 1, wherein automatically measuring range comprises sweeping a laser pulse outputted by the laser device through the field of view.

4. The method of claim 3, wherein the laser device includes a pulsed laser.

5. The method of claim 1, wherein automatically measuring range comprises outputting an acoustic signal, detecting a reflection of the outputted acoustic signal off of a target, determining time of travel based on the outputted acoustic signal and the detected reflection, and measuring range of targets based on the determined time of flight.

6. The method of claim 1, wherein the human tissue safety model is based on type of laser beam outputted by the laser device.

7. The method of claim 6, wherein the human tissue safety model is further based on atmospheric conditions.

8. The method of claim 7, further comprising automatically determining atmospheric conditions.

9. A Laser Imaging, Detection and Ranging (LIDAR) system comprising:

a component configured to automatically measure range to one or more targets in a field of view and determine the closest one of the targets based on the measured range;

a laser device configured to output a laser beam; and

a controller configured to adjust at least one of pulse repetition frequency, pulse amplitude, power, pulse duration, or optical intensity of the laser device based on the measured range of the closest target in order to comply with predefined human tissue safety model.

10. The system of claim 9, wherein the human tissue safety model includes at least one of an eye safety model or a skin safety model.

11. The system of claim 9, wherein the laser device includes a pulsed laser.

12. The system of claim 9, wherein the component comprises an acoustic target measuring device configured to output an acoustic signal, detect reflections of the outputted acoustic signal, and measure range of targets based on the outputted acoustic signal and a determined time of flight of the detected reflections.

13. The system of claim 9, wherein the human tissue safety model is based on type of laser beam outputted by the laser device.

14. The system of claim 13, wherein the human tissue safety model is further based on atmospheric conditions.

15. The system of claim 14, further comprising a device configured to automatically determine atmospheric conditions.

16. A Laser Imaging, Detection and Ranging (LIDAR) system comprising:

a means for outputting a laser pulse;

a means for sensing reflections of the outputted laser pulse;

a component configured to measure range to one or more targets based on the sensed returns and determine the closest one of the targets based on the measured range; and

a controller configured to adjust at least one of pulse repetition frequency, pulse amplitude, power, pulse duration, or optical intensity of the laser device based on the measured range of the closest target in order to comply with predefined human tissue safety model.