1. Troy Owens, John Trytko, Adam Ornstein, Dmitriy Polyakov, Michael Tanksalvala

2.  System measures the phase shift of light to determine the concentration of particles in the air Light accumulates a media-dependent phase shift as it resonates in the cavity Higher concentration of particles induce a larger phase shift  This is used in conjunction with other instruments to compute specific concentrations of various aerosols John Dmitriy Michael Adam Troy

3. Laser Controller Laser Photodiode Beam Splitter Ringdown Cavity Phase Shift Detector John Dmitriy Michael Adam Troy Kebabian, Paul L., Scott C. Herndon, and Andrew Freedman. "Detection of Nitrogen Dioxide by Cavity Attenuated Phase Shift Spectroscopy." Analytical Chemistry 77.2 (2005): 725. Print.

4.  Applications: Reference for specialized particle-detecting systems Measure aerosol content in open air Air quality  Advantages: Compact and portable Turn-key (no knowledge of instrument required) Self-aligning optics Autonomous data collection John Dmitriy Michael Adam Troy

5.  Low Priority Achieve awesomeness – easy with lasers Detect phase shift on optical breadboard  Medium Automated laser alignment system Data storage No use of external lab equipment  High Compact (backpack size) system Entirely autonomous (after easy startup) John Dmitriy Michael Adam Troy

6. Power John Dmitriy Michael Adam Troy

7.  Successful signal detection  Cavity must establish and maintain an optical standing wave  Mechanical stability  Meaningful output from photodiode  Final output in specified file format  Time!!! John Dmitriy Michael Adam Troy

8.  Environmental impact Difficult to dispose of parts Beam doesn’t interfere with the environment  Safety Laser can damage eye Low power laser John Dmitriy Michael Adam Troy

9.  Class IIIa-IIIb (continuous wave, 1 to 20 mW) Visible wavelengths (350 – 800 nm) Low power/area (< 2 mW/cm 2 )  Hazards Corneal damage only (safe exposure time is roughly.25 seconds) Non-permanent retinal damage if viewed for 1 to 2 seconds, permanent viewed for longer Do not look into the laser John Dmitriy Michael Adam Troy

10.  Manufacturability Intended for singular creation Mass production unlikely Easily portable  Sustainability Low power consumption Durable parts and reliable electronics John Dmitriy Michael Adam Troy

12.  Laser controller (enabling phase detection)  Concave mirrors for the cavity  Controllable mirror mounts (enabling feedback control)  Beam-splitter  Photodiode (signal measurement)  CMOS Camera (sensor for feedback) John Dmitriy Michael Adam Troy

13. Laser Controller Laser Photodiode Beam Splitter Ringdown Cavity Phase Shift Detector John Dmitriy Michael Adam Troy Image obtained from: http://www.chem.ualberta.ca/~xu/research/crds.htm

14.  Objective: Maintain maximum signal power  Keeps beam pointed at photodiode using PID Controller  If signal is lost, methodically scans over area to try to find it  Concave mirrors provide small amount of passive beam alignment John Dmitriy Michael Adam Troy

15.  Constructed from normal mirror mounts and (disassembled) piezoelectric buzzers  Piezoelectric ceramic expands when voltage is applied John Dmitriy Michael Adam Troy

16. Laser Controller Laser Beam Splitter Alignment System CMOS Camera Micro- Controller John Dmitriy Michael Adam Troy

17.  Create circuit to connect camera to computer Helps for debugging during and after development Enables good capstone demo  Add controllable mirror and microcontroller Beam-steering functionality Software-based PID signal maximization Signal-finding  Add second mirror and integrate it into PID John Dmitriy Michael Adam Troy

18. Laser Controller Laser Photodiode Beam Splitter Alignment System John Dmitriy Michael Adam Troy

19.  Processing Time Camera can output millions of datapoints 20 MHz processor  Number of Cameras  Signal strength at Camera  Contingency plan: Using concave mirrors provides a self-aligning force, so even without active feedback, measurements can be made John Dmitriy Michael Adam Troy

20.  SD Card Storage of phase, timestamp, and “valid bit” OS Storage (cold-start)  Clock Microcontroller oscillator Timestamps John Dmitriy Michael Adam Troy

21. Battery User Interface Hardware Clock Micro- Controller Phase Shift Detector Solid State Drive SD John Dmitriy Michael Adam Troy

22.  SD Card Storage of phase, timestamp, and “valid bit” OS Storage (cold-start)  Clock Microcontroller oscillator Timestamps John Dmitriy Michael Adam Troy

23. ADCSD Card Time I/O Data ProcessingTime ManagementData Formatting OS / μC John Dmitriy Michael Adam Troy

24. SD John Dmitriy Michael Adam Troy

25. TaskPrimarySecondary OS Design and Data StorageAdamMichael Mechanical Structure/AlignmentDmitriyJohn Control SystemsMichaelAdam Power systemTroy Board Layout/ConstructionJohn, AdamTroy, Michael Optical Construction and Detection JohnDmitriy Design DocumentationAll Chief Financial Officer (CFO)Michael John Dmitriy Michael Adam Troy

27. EquipmentEstimated Price Laser ControllerBorrowed from NOAA Laser Borrowed from NOAA Mirror Mounts/Mirrors Borrowed from NOAA Photodiode $20 1-2 x Beam-Sampler 1-2 x $60 MSP430 $40 ATMega328 $5 16-Pin AVR Development Board $20 1-2 x CMOS Camera 1-2 x $35 1-2 x PCB1-2 x $60 Piezoelectric Buzzer$5 Other$100 TOTAL$345 - $500 John Dmitriy Michael Adam Troy

28.  NOAA Providing optical parts (mirrors, mounts, laser controller, optical breadboard, laser) Will keep the prototype upon completion  UROP Funding (Pending) Up to $1000 funding Requires a report upon completion John Dmitriy Michael Adam Troy

29.  Not able to integrate OS with Optics Will demonstrate the systems separately at Expo  Not able to construct casing for a portable device Demonstrate the project on separate breadboards at Expo John Dmitriy Michael Adam Troy

30. Alex TomBob Sam Carissa Image obtained from: http://www.picgifs.com/graphics/noahs-ark/