ECE-1466 Modern Optics Course Notes Part 5 Prof. Charles A. DiMarzio Northeastern University Spring 2002 Mayl 02002 Chuck DiMarzio, Northeastern University

Basic Equations of Interference Im E Re E Mayl 02002 Chuck DiMarzio, Northeastern University

Chuck DiMarzio, Northeastern University Mach Zehnder (1) Example M2 BS1 Source, s Gas Cell n>1 M1 BS2 Straight-Line Layouts: Transit Time s BS1 M1 BS2 s BS1 M2 BS2 Geometric s BS1 M1 BS2 s BS1 M2 BS2 Mayl 02002 Chuck DiMarzio, Northeastern University

Chuck DiMarzio, Northeastern University Mach Zehnder (2) Straight-Line Layout: Transit Time s BS1 M1 BS2 s BS1 M2 BS2 q Diffuser Mayl 02002 Chuck DiMarzio, Northeastern University

Chuck DiMarzio, Northeastern University Optical Testing M1, Known Reference Spheres 4-wave difference Same with 2-wave bump -50 50 0.5 1 1.5 2 -50 50 0.5 1 1.5 BS M2, Mirror Under Test Flats with 8-wave tilt Same with 2-wave bump -50 50 0.5 1 1.5 2 -50 50 0.5 1 1.5 2 Mayl 02002 Chuck DiMarzio, Northeastern University

Fabry-Perot Interferometer (1) Straight Line Model Multiple Sources, with decreasing amplitudes (usually) and increasing distances (and thus phases). Mayl 02002 Chuck DiMarzio, Northeastern University

Fabry-Perot Interferometer (2) 10mm 650nm 600nm 460 470 480 490 500 0.05 0.1 0.15 0.2 0.25 f, Freq., THz T, Transmission FSR d f Mayl 02002 Chuck DiMarzio, Northeastern University

Chuck DiMarzio, Northeastern University Laser Tuning (1) Gain Lines Depend on Medium Often Multiple 10’s to 100’s of THz. Cavity Modes qc/2L q is an inteter L is cavity length Free Spectral Range c/2L (Mode Spacing) Gain f Cavity Modes f Mayl 02002 Chuck DiMarzio, Northeastern University

Chuck DiMarzio, Northeastern University Laser Tuning (2) Fine Tuning Cavity Length Usually Piezoelectric Intracavity Modulator Single Mode Intracavity Etalon or Short Cavity Single Gain Line Prism or Grating Gain f Cavity Modes f qi Mayl 02002 Chuck DiMarzio, Northeastern University

Chuck DiMarzio, Northeastern University Etalon Transmission Only Coherent Sources contribute to the fringes Im (1/t) Re (1/ t) Mayl 02002 Chuck DiMarzio, Northeastern University

Thin Films: Three Approaches Sum the multiple Reflections Use Wave Equation and Boundary Conditions Network Approach with Fresnel Coefficients EA EB EC ED E1 E2 E3 E4 E’1 E’2 E’3 E’4 Mayl 02002 Chuck DiMarzio, Northeastern University

Chuck DiMarzio, Northeastern University Thin Film Matrices (2) M1 M4 M=M1M2M3M4 Mayl 02002 Chuck DiMarzio, Northeastern University

High Reflection Stack (1) Mayl 02002 Chuck DiMarzio, Northeastern University

High Reflection Stack (2) Phase=0 p+p 2p+0 3p+p Sign of Reflectivity is inverted on going from High to Low Index. Mayl 02002 Chuck DiMarzio, Northeastern University

Anti-Reflection Coatings Examples R Uncoated Glass 4% Two Layers One Layer Phase =0 p Three Layers Quarter-Wave Coating Magnesium Flouride n=1.35 is a close match, low cost and durable. l Violet Red Mayl 02002 Chuck DiMarzio, Northeastern University

Interference Magnitudes Mayl 02002 Chuck DiMarzio, Northeastern University

Quadrature Imaging Concept Balanced Mixing November 18

Quadrature Images from Original Setup One-Cell Embryo Two-Cell Embryo Amplitude Phase Amplitude Phase Multi-Cell Blastocyst Amplitude Phase Images by Dan Hogenboom, NU November 18

Quadrature Imaging Microscope Design Design Features 4 CCD Cameras - Balanced Mixing 10x and 20x Interchangeable Objectives Virtual Pinhole Focusing System November 18

Original Setup November 18

Experiment vs. Analytical Model Fiber Model: n=1.43-1.46-1.48 Position - mm/pixel -50 50 20 40 60 80 100 -3 -2 -1 1 2 3 Fiber in Sugar Water Position - 0.9mm/pixel 50 100 150 200 250 300 350 -3 -2 -1 1 2 3 November 18

Unwrapped Phase Image of a Mouse Oocyte Amplitude Unwrapped Phase Phase 10027.jpg 3993.jpg 10028.jpg Mayl 02002 Chuck DiMarzio, Northeastern University

How Could QTM Count Cells in Compact Embryo? QTM Phase DIC Assumed Index Profile Before Compaction 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 -3 -2 -1 1 2 3 M10026.m M10026.m Assumed Index Profile During Compaction 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.5 1 1.5 2 2.5 M10026.m M10026.m Mayl 02002 Chuck DiMarzio, Northeastern University

Chuck DiMarzio, Northeastern University Third Generation QTM Q . Mayl 02002 Chuck DiMarzio, Northeastern University