switch your focus to equalization what nonlinear optics can do for you cecilia j. vogel research...
Post on 22-Dec-2015
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SWITCH YOUR FOCUS TO EQUALIZATION
What Nonlinear Optics
Can do for You
Cecilia J. Vogel
research with Dr. D. Andersen University of Iowa
SWITCH YOUR FOCUS TO EQUALIZATION
What Nonlinear Optics
Can do for You
Cecilia J. Vogel
research with Dr. D. Andersen University of Iowa
SWITCH YOUR FOCUS TO EQUALIZATION
What Nonlinear Optics
Can do for You
Cecilia J. Vogel
research with Dr. D. Andersen University of Iowa
SWITCH YOUR FOCUS TO EQUALIZATION
What Nonlinear Optics
Can do for You
Cecilia J. Vogel
research with Dr. D. Andersen University of Iowa
SWITCH YOUR FOCUS TO EQUALIZATION
What Nonlinear Optics
Can do for You
Cecilia J. Vogel
research with Dr. D. Andersen University of Iowa
SWITCH YOUR FOCUS TO EQUALIZATION
What Nonlinear Optics
Can do for You
Cecilia J. Vogel
research with Dr. D. Andersen University of Iowa
Nonlinearity• Linear:
• The glass is half full• m = V
• Nonlinear:
• The glass is 49.999999…% full• m = V) V
Nonlinear Optics
• Linear Optics: D=E
• Light is slowed in material by a factor of n, leads to refraction
• If very intense, and n depend on intensity
Self-focusing• Light has a tendency to diverge
• Must maintain narrow beam for laser
Self-focusing• Light has a tendency to diverge
• Lens slows light with glass
• Light bent toward the slower region
Slowed more
Slowed less
Slowed less
Self-focusing• Light has a tendency to diverge
• Solid state laser can use self-focusing
• Slowed most where beam is most intense
Slowed more
Slowed less
Slowed less
Optical switch
• Can a signal beam be switched from one path (0) to another (1)?
Optical switch
• Can a signal beam be switched from one path (0) to another (1)?
• Guide beam alters the nonlinear material
• Signal beam bent toward it
Signal beam
Guide beam
0
Signal beam
Guide beam
0
Signal beam
Guide beam
Signal beam
Guide beam
Signal beam
Guide beam
1
Equalization Needs
• Single fiber -- many signals
• Each signal -- a different wavelength
Equalization Needs
• Single fiber -- many signals
• Each signal -- a different wavelength
• Each signal degrades independently
• Needs to be boosted independently
Equalization
• Easy to boost all by same factor -- not equalized
Equalization
• First dim the brightest• Linear filter: transmission spectrum
constant
• Then boost all by same factor
Equalization
• First dim the brightest to match the dimmest
• Nonlinear: Transmission depends on intensity
• Then boost all by same factor