1. Casper Maheshwari advisors: Stephen Ulhorn & E. Duco Jansen Department of Biomedical Engineering Vanderbilt University http://vubme.vuse.vanderbilt.edu/casper/home.htm Design of an OCT Probe

2. Project Description zDesign, build, and implement a palm-size probe that can be used at the sample arm of an OCT imaging system. zThis probe will be used to differentiate between normal and tumor brain tissue.

3. What is OCT? zOptical Coherence Tomography is an imaging modality that produces 3-D images of biological microstructures. zThe heart of the OCT system consists of a Michaelson Interferometer. ySample Arm (lateral scanning) yReference Arm (longitudinal scanning) zThe laser travels through the sample and reflects off biological microstructures. y(depth scanning)

4. OCT Block Diagram LUMINESCENT DIODE sample 50/50 BANDPASS FILTER ENVELOPE DETECTOR A/D COMPUTER LATERAL SCANNING LONGITUDINAL SCANNING PROBE MODULE

5. ParametersParameters zDefined  Wavelength = 1.3  m yTotal Optical Path Distance = 49.0 cm yDepth of Focus between 3.0-5.0 mm yLateral Scanning Distance = 5.0 mm zCalculated yCollimating Lens: f = 4.4 mm xBeam diameter = 1.15 mm yFocusing Lens: f = 40 mm xDepth of Focus = 4.0 mm yFiber Patch Cord Length = 29.31 cm

6. Proposed Probe Design scanner Fiber l = 29 cm collimating lens f = 4.4 mm focusing lens f = 40 mm sample 5 mm 40 mm 1.15 mm diameter 

7. Completed Work z Library research of already existing probes z Arrival of the OCT system parts z Assembly of the OCT system z Basic probe design z Calculation of probe parameters z Order of probe components

8. Current Work z Awaiting Arrival of Probe components ycollimating and focusing lenses ypatch fiber cord  Ray Tracing on Optics Lab ®

9. Costs z Fiber Patch Cord$ 51.00 z Collimating Lens$ 44.00 z Focusing Lens$ 88.00 z Total (to date)$ 183.00

10. Future Work & Problems z Future Work yconstruct a probe prototype ydesign and make housing for the probe ytest out probe with basic experiments z Problems yThe desired scanner takes 10-12 wks to arrive yAspheric collimating lens unavailable