1. Automated Spotsize Measurement
Brian Lenahan
Melisa Moore
Advised by:
Dr. Duco Jansen

2. Proposal and Expectations
Measure the spotsize of a laser
Accurate within 10 microns
Suitable for mm diameter beam
Fully automated
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3. Why We Measure Spotsize
Irradiance [W/mm2]
Evaluate new materials
Gaussian beam profile
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4. Gaussian FEL profile proven to be Gaussian
Consistent property of the FEL
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5. Experimental Setup
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6. EPM 2000
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7. MM 3000
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8. Spotsize Algorithm Straight-Edge Technique Algorithm
b-1 = (x10-x90)
d = 2Ö2 b-1
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9. LabVIEW Programming language with graphical interface
Common utility for data acquisition & instrument control
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10. Front Panel Layout
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11. Work Completed Reviewed LabVIEW Tutorial & example programs
Modified drivers for EPM 2000 and MM 3000
Resolved hardware problems
Resolved resolution errors
Established communication between the equipment and computer
Combined the EPM 2000 and MM 3000 into overall VI design
Completed preliminary testing
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12. Preliminary Testing
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13. Current Work
Refining programs
Developing full automation
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14. Future Work Develop accuracy specifications More testing
Produce working model
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15. References LabVIEW Tutorial LabVIEW Reference Manual
EPM2000 and MM3000 user manuals
Duco Jansen, VU BME professor
Hans Pratisto, former VU BME post-doc
BME 290d Optics Lab handouts
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