PHYS 252 / 2021 PHYS 252 & PHYS 202 Polarization Scattering Absorption.

of 19/19
PHYS 252 / 202 1 PHYS 252 & PHYS 202 Polarization Scattering Absorption
  • date post

    31-Dec-2015
  • Category

    Documents

  • view

    230
  • download

    1

Embed Size (px)

Transcript of PHYS 252 / 2021 PHYS 252 & PHYS 202 Polarization Scattering Absorption.

  • PHYS 252 & PHYS 202PolarizationScatteringAbsorption

    PHYS 252 / 202

  • Polarizationlinearly polarizedaxis is in one directionelliptically polarizedaxis sweeps out ellipse over timecircularly polarizedaxis sweeps out circle over timeunpolarizedaxis changes direction randomly

    PHYS 252 / 202

  • Polarizationlinearly polarized

    PHYS 252 / 202

  • Polarization

    PHYS 252 / 202

  • PolarizationLinear Polarization of Light by Dichroic Polarizer (Polaroid)

    PHYS 252 / 202

  • PolarizationEffect of a Single Polaroid on Linearly Polarized Lightall light passes throughless light passes througheven less light passes throughno light passes through

    PHYS 252 / 202

  • PolarizationTwo PolaroidsI = Io cos2The Law of Malus

    PHYS 252 / 202

  • PolarizationLinear Polarization of Light by Reflectionpolarization angle

    PHYS 252 / 202

  • PolarizationLinear Polarization of Light by Reflection

    PHYS 252 / 202

  • PolarizationBirefringent MaterialBirefrigencematerial exhibits two values of refractive index for each frequency of lightthe value depends on the orientation of the electric field with the optic axis of the material

    PHYS 252 / 202

  • PolarizationLinear Polarization of Light by Birefringent Crystal

    PHYS 252 / 202

  • PolarizationRotation of Polarization Axis by Birefringent MaterialAmount of rotation depends on thickness of material wavelength of light values of refractive index

    PHYS 252 / 202

  • ScatteringAtoms, molecules, and small particles scatter light by absorbing it and re-emitting it in random directions.Amount of scattering depends on size of scatterers wavelength of light

    PHYS 252 / 202

  • Scattering shorter wavelengths scatter much more than longer wavelengths

    PHYS 252 / 202

  • ScatteringRayleigh Scattering

    PHYS 252 / 202

  • ScatteringLinear Polarization by Scattering

    PHYS 252 / 202

  • AbsorptionAtoms and molecules will absorb light energy of certain frequencies (and wavelengths) much better than others.A plot of the amount of absorption versus frequency (or wavelength) is called a materials absorption spectrum.

    Some example absorption spectra appear on the next slides.

    PHYS 252 / 202

  • AbsorptionAbsorption Spectra of Some Organic Materials1.bacteriochlorophyll 2.chlorophyll A 3.chlorophyll B 4.phycoerythroblin 5.beta caroteneA careful look at the chlorophyll spectra will explain why most plants are green!

    PHYS 252 / 202

  • AbsorptionWhat color is this material?

    PHYS 252 / 202