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
2/24/99

3. Why We Measure Spotsize
Irradiance [W/mm2]
Evaluate new materials
Gaussian beam profile
2/24/99

4. Gaussian FEL profile proven to be Gaussian
Consistent property of the FEL
2/24/99

5. Experimental Setup
2/24/99

6. Spotsize Algorithm Straight-Edge Technique Algorithm
b-1 = (x10-x90)
d = 2Ö2 b-1
wl = d/2
2/24/99

7. LabVIEW Programming language with graphical interface
Common utility for data acquisition & instrument control
2/24/99

8. Front Panel Layout
2/24/99

9. Work Completed Reviewed LabVIEW Tutorial & example programs
Top - Down Engineering
Modified drivers for EPM 2000 and MM 3000
Resolved hardware problems
Resolved resolution errors
Established communication between the equipment and computer
Constructed portable spotsize measurement platform
2/24/99

10. Current Work Combining individual drivers into overall algorithm
Develop movement specifications
2/24/99

11. Future Work Develop accuracy specifications
Resolve any programming complications
Produce working model
2/24/99

12. References LabVIEW Tutorial LabVIEW Reference Manual
EPM2000 and MM3000 user manuals
Duco Jansen, VU BME professor
Hans Pratisto, VU BME post-doc
BME 290d Optics Lab handouts
2/24/99