1. Hadamard Transform Imaging Paul Holcomb Tasha Nalywajko Melissa Walden

2. Problem Definition Current 3D spectral imaging systems are relatively slow and possess low resolution Hadamard multiplexing greatly enhances signal to noise ratio, thus enhancing resolution Use of a digital micro-mirror device makes implementation of the Hadamard transform very fast

3. Hypothesis Implementation of the Hadamard transform in a spectral imaging system by using a digital micro- mirror device will decrease the amount of time necessary to acquire an image and increase the spatial and spectral resolution of the image. Faster, more accurate spectral imaging will allow for better differentiation of tissue during brain tumor resectioning and increase survival rates.

4. 3D Spectral Imaging Techniques - Scanning Wavelength Scanning http://www.cri-inc.com/instruments/data/pdf/American%20Laboratory%202000.pdf Line Scanning http://www.lightforminc.com/Technology/ANIMATION/animation.html

5. 3D Spectral Imaging Techniques - Multiplexing Fourier Transform http://scienceworld.wolfram.com/physics/FourierTransformSpectrometer.html Wuttig and Riesenburg, “Sensitive Hadamard Transform Imaging Spectrometer with a simple MEMS” Hadamard Transform

6. Benefits of Hadamard Multiplexing Decreased image acquisition time vs. scanning techniques Increased signal to noise ratio  √n for Hadamard matrix  (√n)/2 for S matrix Wuttig and Riesenburg, “Sensitive Hadamard Transform Imaging Spectrometer”

7. What do we want? Focus a 25 mm square into a 10 mm square Bounce the square with specific pixels at specific angles (apply Hadamard matrix) Compress the light in one direction  line Separate the line by wavelength Goal: Capture the spectrum of the line

8. Stage 1 – Compress image

9. Digital Micro-Mirror Device http://www.ostl.ece.uvic.ca/IMAGES/emiod.png

10. Stage 2 – Compress into a line

11. Drawn to scale…

12. Stage 1

13. Construction

14. Lens System with Testing Lens

15. Testing of Stage 1

16. Testing with Square Source

17. Why is this important? 71% mortality rate for diagnosed brain tumors Correlation between complete resectioning of tumors and improved prognosis Complete resectioning requires knowing the location of the tumor, especially tumor margins Imaging in a clinical setting should be fast

18. Future Directions Finish construction and testing by mid- January Implement 2 leg system (Full Hadamard) Miniaturization Thanks from Group 10!