Automated focusing, cleaning, and multiple location sampling spectrometer system
An analysis system includes a moveable focusing lens, a laser (typically an eye safe laser) having an output directed at the focusing lens, and a spectrometer outputting intensity data from a sample. A controller system is responsive to the spectrometer and is configured to energize the laser, process the output of the spectrometer, and adjust the position of the focusing lens relative to the sample until the spectrometer output indicates a maximum or near maximum intensity resulting from a laser output focused to a spot on the sample.
1. A spectroanalysis method comprising:
directing a laser output to a sample through an adjustable focusing lens;
using a spectrometer to detect spectral intensity data from the sample; and
initiating a focusing cycle wherein the laser is energized, the spectral intensity data from the spectrometer is analyzed, and the position of the focusing lens is automatically adjusted until the spectral intensity data is maximized resulting from the laser output focused on the sample.
2. The method of claim 1 in which the laser output wavelength is approximately 1.5 μm.
3. The method of claim 1 in which the laser is a class 1or class 2laser.
4. The method of claim 1 in which the laser spot has a size equal to or less than 100 μm on the sample.
5. The method of claim 1 in which the intensity is an integrated intensity over a plurality of wavelengths.
6. The method of claim 1 in which adjusting the position of the focusing lens includes moving it away from the sample and towards the sample.
7. The method of claim 1 further including directing focused laser energy to multiple locations on the sample.
8. The method of claim 7 further including initiating a moving spot cycle.
9. The method of claim 8 further including terminating the moving spot cycle when the spectrometer output does not change by a predetermined amount between different sample locations.
10. The method of claim 7 further including adjusting the position of the focusing lens at each sample location.
11. The method of claim 1 further including initiating a cleaning cycle and terminating the cleaning cycle.
12. The method of claim 11 including processing the spectrometer output and energizing the laser in a cleaning mode until the output stabilizes.
13. The method of claim 12 in which the cleaning cycle terminates when a rolling average of at least one peak intensity changes by less than a predetermined percentage.
14. The method of claim 11 further including moving the position of the focusing lens producing a larger spot size during the cleaning cycle.