Digital boresighting laser range finder to imaging device

Patent metadata

Field	Value
Publication number	US-11178332-B2
Application number	US-201815863111-A
Country	US
Kind code	B2
Filing date	Jan 5, 2018
Priority date	Jan 5, 2018
Publication date	Nov 16, 2021
Grant date	Nov 16, 2021

Abstract

A method of digitally boresighting includes finding a laser spot in a field of view of an imaging device that has an optical center, wherein the laser spot is generated by a laser, determining an offset vector between the laser spot in the field of view and the optical center, and correcting for boresight misalignment of the laser and imaging device in the image on a display using the offset vector.

First claim

What is claimed is:

1. A laser range finder system comprising:
a laser for illuminating a target with a laser spot in a predetermined wavelength;
an imaging device connected to the laser for viewing the target, wherein the imaging device has a field of view with an optical center and is sensitive in the predetermined wavelength;
a display operatively connected to the imaging device for displaying an image of the target; and
a controller operatively connecting the imaging device to the display, wherein the controller includes machine readable instructions that cause the controller to:
find the laser spot in the field of view of the imaging device;
determine an offset vector between the laser spot in the field of view and the optical center; and
correct for boresight misalignment of the laser and imaging device in the image on the display using the offset vector, wherein the controller is operatively connected to the imaging device and includes machine readable instructions that cause an imaging sensor of the imaging device to operate in a binary ON/OFF output first mode sensitive to short duration laser pulses for laser pulse detection, and to operate in a second mode for imaging scenic information for targeting context, wherein the imaging sensor operates with a higher dynamic range and lower frequency in the second mode than in the first mode,
wherein the imaging sensor is a single focal plane array sensor that operates in both the first mode and in the second mode wherein the laser includes a pulse generator configured to illuminate the target with laser pulses, and wherein the imaging device includes an imaging sensor operatively connected to the controller for validating the laser by laser pulse detection based on pulse duration and pulse repetition rate, where the binary ON/OFF mode has a frequency fast enough to detect pulse repetition rate.

2. The system as recited in claim 1 , wherein the machine readable instructions cause the controller to find the laser spot using the sensor in the first mode.

3. The system as recited in claim 1 , wherein correcting for boresight misalignment includes offsetting the image displayed in the display.

4. The system as recited in claim 3 , wherein offsetting the image displayed in the display includes at least one of cropping and/or scaling an image of the field of view of the imaging device to center the laser spot in the image displayed on the display.

5. The system as recited in claim 4 , wherein the laser spot is not visible in the image displayed on the display.

6. The system as recited in claim 1 , wherein correcting for boresight misalignment includes placing a cross-hair over the laser spot in the image displayed on the display.

7. The system as recited in claim 6 , wherein the laser spot is not visible in the image displayed on the display.

8. The system as recited in claim 1 , wherein the laser illuminates the target with a SWIR wavelength including 1550 nm, and wherein the imaging device includes a SWIR imaging sensor operatively connected to the controller for imaging the laser spot and determining the offset vector.

9. The system as recited in claim 1 , wherein the imaging sensor is a first imaging sensor for imaging the laser spot in a first channel and wherein the imaging device further comprises a second imaging sensor for imaging the target in a second channel, wherein the first imaging sensor is sensitive to the predetermined wavelength, and wherein the second imaging sensor is not sensitive to the predetermined wavelength.

10. The system as recited in claim 9 , wherein the second imaging sensor is optically coupled with an interchangeable optic.

11. A laser range finder system comprising:
an imaging device for viewing a target illuminated by a laser, wherein the imaging device has a field of view with an optical center and is sensitive in a predetermined wavelength; and
a controller operatively connected to the imaging device, wherein the controller includes machine readable instructions that cause the controller to:
find the laser spot in the field of view of the imaging device;
determine an offset vector between the laser spot in the field of view and the optical center; and
correct for boresight misalignment of the laser and imaging device in an image on a display using the offset vector, wherein the controller is operatively connected to the imaging device and includes machine readable instructions that cause an imaging sensor of the imaging device to operate in a binary ON/OFF output first mode sensitive to short duration laser pulses for laser pulse detection, and to operate in a second mode for imaging scenic information for targeting context, wherein the imaging sensor operates with a higher dynamic range and lower frequency in the second mode than in the first mode,
wherein the imaging sensor is a single focal plane array sensor that operates in both the first mode and in the second mode, wherein the laser includes a pulse generator configured to illuminate the target with laser pulses, and wherein the imaging device includes an imaging sensor operatively connected to the controller for validating the laser by laser pulse detection based on pulse duration and pulse repetition rate, where the binary ON/OFF mode has a frequency fast enough to detect pulse repetition rate.

12. A method of digitally boresighting comprising:
finding a laser spot in a field of view of an imaging device that has an optical center, wherein the laser spot is generated by a laser;
determining an offset vector between the laser spot in the field of view and the optical center; and
correcting for boresight misalignment of the laser and imaging device in the image on a display using the offset vector;
validating the laser by laser pulse detection based on pulse duration and pulse repetition rate; and
operating a first imaging sensor in a binary ON/OFF output first mode sensitive to short duration laser pulses for laser pulse detection, and operating the first imaging sensor in a second mode for imaging scenic information for targeting context, wherein the first imaging sensor operates with a higher dynamic range and lower frequency in the second mode than in the first mode,
wherein the imaging sensor is a single focal plane array sensor that operates in both the first mode and in the second mode, wherein the laser includes a pulse generator configured to illuminate the target with laser pulses, and wherein the imaging device includes an imaging sensor operatively connected to the controller for validating the laser by laser pulse detection based on pulse duration and pulse repetition rate, where the binary ON/OFF mode has a frequency fast enough to detect pulse repetition rate.

13. The method as recited in claim 12 , wherein correcting for boresight misalignment includes offsetting the image displayed in the display.

14. The method as recited in claim 13 , wherein offsetting the image displayed in the display includes at least one of cropping and/or scaling an image of the field of view of the imaging device to center the laser spot in the image displayed on the display.

15. The method as recited in claim 12 , wherein correcting for boresight misalignment includes placing a cross-hair over the laser spot in the image displayed on the display.

16. The method as recited in claim 12 , wherein the laser spot is not visible in the image displayed on the display.

Assignees

• Sensors Unlimited Inc

Inventors

• Lund Joshua

Classifications

• H04N23/60

  Control of cameras or camera modules · CPC title

• H04N23/63 Primary

  by using electronic viewfinders · CPC title

• G01S7/4972 Primary

  Alignment of sensor · CPC title

• H04N23/56

  provided with illuminating means · CPC title

• H04N23/667

  Camera operation mode switching, e.g. between still and video, sport and normal or high- and low-resolution modes · CPC title