Energy insertion into seeker

Patent metadata

Field	Value
Publication number	US-10539395-B2
Application number	US-201815911561-A
Country	US
Kind code	B2
Filing date	Mar 5, 2018
Priority date	Mar 5, 2018
Publication date	Jan 21, 2020
Grant date	Jan 21, 2020

Abstract

A system and method for improved detection of lasers for use in laser guidance systems. By providing background illumination via one or more radiation sources the accuracy of the laser detection system can be improved. A closed loop system detects the background current on the detector and provides additional illumination when the back ground level is below a threshold current value thus providing for a faster detector response.

First claim

What is claimed:

1. A method for improving detection in a laser guidance system, comprising:
measuring an initial pixel array background current on a focal plane array;
comparing the initial pixel array background current to a threshold current value via a processing unit; and
if the initial pixel array background current is below the threshold current value, providing an additional radiation energy to the focal plane array via a light source, thereby improving detection in the laser guidance system.

2. The method for improving detection according to claim 1 , further comprising updating the initial pixel array background current at a frequency of about 10 kHz.

3. The method for improving detection according to claim 1 , further comprising converting the initial pixel array background current to a digital signal that is provided as a serial peripheral interface read-only register to at least one processing unit.

4. The method for improving detection according to claim 3 , where the serial peripheral interface read-only register is read out at greater than about 20 kHz with a serial peripheral interface clock at about 1 MHz.

5. The method for improving according to claim 1 , further comprising a read out integrated circuit (ROTC) in communication with the focal plane array.

6. The method for improving detection according to claim 5 , wherein the ROIC uses a ROIC direct injection or a buffered direct injection pixel input configuration for each of a plurality of pixels in the focal plane array.

7. The method for improving detection according to claim 5 , further comprising determining the threshold current value comprising:
establishing probable threshold current values during the read out integrated circuit (ROIC) design phase;
calibrating the focal plane array by measuring the total background current;
testing the sensitivity and speed response for the focal plane array; and
updating the threshold current value once the focal plane array has been calibrated.

8. The method for improving detection according to claim 1 , further comprising detecting, via the focal plane array, a laser pulse from a laser source having a pulse width of 10 ns or less.

9. A semi active laser seeker, comprising:
a focal plane array located within a housing and configured to receive radiation signals of a scene and configured to provide an initial pixel array background current value;
a processing unit configured to compare the initial pixel array background current value to a threshold current value and when the initial pixel array background current is below the threshold current value to determine an additional amount of radiation energy; and
one or more radiation sources located within the housing for providing the additional radiation energy to the focal plane array to reach the threshold current value.

10. The semi active laser seeker according to claim 9 , further comprising a lambertian lens retainer for directing the radiation sources.

11. The semi active laser seeker according to claim 9 , wherein the radiation sources are laser emitting diodes.

12. The semi active laser seeker according to claim 9 , further comprising one or more lenses in the housing that receive the incoming radiation signals wherein one of the one or more lenses comprises a narrow band dichroic filter.

13. The semi active laser seeker according to claim 9 , wherein the processing unit comprises at least one microcontroller.

14. The semi active laser seeker according to claim 9 , wherein the processing unit comprises a serial peripheral interface.

15. The semi active laser seeker according to claim 9 , wherein the focal plane array comprises a sensor and a read out integrated circuit.

Assignees

• Bae Sys Inf & Elect Sys Integ

Inventors

• Dimitrov Dimitre P
• Choiniere Michael J
• Whitwam Jason T

Classifications

• G01S3/784

  using a mosaic of detectors · CPC title

• F41G7/001 Primary

  Devices or systems for testing or checking · CPC title

• G01S3/7803

  Means for monitoring or calibrating · CPC title

• F41G7/226 Primary

  Semi-active homing systems, i.e. comprising a receiver and involving auxiliary illuminating means, e.g. using auxiliary guiding missiles · CPC title

• F41G7/2293

  using electromagnetic waves other than radio waves · CPC title