Flashlamp Degradation Monitoring System and Method

• US 20160084896A1
• Filed: 09/23/2014
• Published: 03/24/2016
• Est. Priority Date: 09/23/2014
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Jungwirth, Douglas R., Bouckaert, Anton M.
• Granted Patent: US 9,970,971 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01J 1/42 using electric radiation detectors optical or mechanical part G01J1/04; by comparison with a reference light or electric value G01J1/10
• CPC Class Codes: G01J 2001/4238 Pulsed light
• CPC Class Codes: G01N 21/88 Investigating the presence of flaws or contamination
• CPC Class Codes: G01N 2201/088 Using a sensor fibre
• CPC Class Codes: G01R 17/00 Measuring arrangements involving comparison with a reference value, e.g. bridge
• CPC Class Codes: G01R 19/0046 characterised by a specific application or detail not covered by any other subgroup of G01R19/00
• CPC Class Codes: G01R 29/027 Indicating that a pulse characteristic is either above or below a predetermined value or within or beyond a predetermined range of values
• CPC Class Codes: G01R 31/245 Testing of gas discharge tubes

Abstract

A method for monitoring degradation of a flashlamp including triggering the flashlamp to produce a light pulse, monitoring at least one parameter as a function of time to obtain a pulse waveform of the light pulse, comparing the pulse waveform to at least one reference pulse waveform to determine a difference therebetween, and flagging an end-of-lamp-life condition when the difference exceeds a predetermined threshold.

Claims

1. A method for monitoring degradation of a flashlamp comprising:

triggering the flashlamp to produce a light pulse;

monitoring at least one parameter as a function of time to obtain a pulse waveform of the light pulse;

comparing the pulse waveform to at least one reference pulse waveform to determine a difference therebetween; and

flagging an end-of-lamp-life condition when the difference exceeds a predetermined threshold.

2. The method of claim 1 wherein the flashlamp comprises an ionizable gas sealed in an envelope.

3. The method of claim 2 wherein the ionizable gas comprises xenon.

4. The method of claim 2 wherein the triggering step comprises applying a voltage having a magnitude sufficient to initiate ionization of the ionizable gas.

5. The method of claim 1 wherein the monitoring step comprises electronically monitoring the parameter.

6. The method of claim 5 wherein the parameter is electric current.

7. The method of claim 5 wherein the parameter is voltage.

8. The method of claim 1 wherein the monitoring step comprises optically monitoring the parameter.

9. The method of claim 8 wherein the parameter is light energy.

10. The method of claim 1 wherein the pulse waveform has a substantially square-wave shape.

11. The method of claim 1 further comprising storing the pulse waveform.

12. The method of claim 1 wherein the reference pulse waveform comprises a pulse waveform from a previous light pulse.

13. The method of claim 1 wherein the comparing step comprises at least one of a cross-correlation analysis, a derivative analysis and a linear approximation analysis.

14. The method of claim 1 wherein the predetermined threshold is of a magnitude sufficient to allow normal pulse waveform-to-pulse waveform variation without flagging the end-of-lamp-life condition.

15. The method of claim 1 wherein the flagging step comprises providing at least one of a visual indication and an audible indication of the end-of-lamp-life condition.

16. The method of claim 1 wherein the flagging step comprises disabling the flashlamp.

17. A flashlamp degradation monitoring system comprising:

a flashlamp comprising an envelope housing an ionizable gas and opposed electrodes;

a power supply electrically coupled to the electrodes;

a trigger positioned to initiate ionization of the ionizable gas and generate a light pulse;

a sensor positioned to monitor at least one parameter as a function of time, thereby yielding a pulse waveform for the light pulse; and

a computer in communication with the sensor, wherein the computer is configured to compare the pulse waveform with at least one reference pulse waveform.

18. The system of claim 17 wherein the sensor is current sensor or a voltage sensor.

19. The system of claim 17 wherein the sensor is an optical detector.

20. The system of claim 19 further comprising a lens positioned to focus the light pulse onto the optical detector.