Fiber Optic Tutorials

Sir George Gabriel Stokes (1819 - 1903) was led to his formulation of Stokes Polarization Parameters in order to provide a suitable mathematical description of the Fresnal-Arago laws. Fresnel–Arago Laws (1811) are based on experiments carried out with an unpolarized light source. The original laws were stated as: Two rays of light polarized in the same plane interfere in the same manner as ordinary light Two rays at right angles do not interfere Two rays polarized at right angles from ordinary light and brought into the same plane of polarization do not interfere in the ordinary sense Two rays polarized...

Jones Matrix For background information about Jones vectors, please check out this article. We now study the matrix forms for polarizing elements. In order to do this, we have an assumption: The components of a light beam emerging from a polarizing element are linearly related to the components of the incident light beam. This relationship can be expressed in equations as:   where Ex', Ey' are the components of the emerging light beam, and Ex , Ey are the components of the incident light beam. The quantities Jxx, Jxy, Jyx, Jyy are the transforming factors of this polarizing element. We can rewrite...

Complex Amplitudes of a Monochromatic Beam in Isotropic and Homogeneous Medium When a light beam propagates in an isotropic and homogeneous medium, the beam can be represented by its electric field E(r,t), which can be written: E(r,t) = A cos(ωt - k • r)                     (1) where A is a constant vector representing the amplitude, ω is the angular frequency, k is the wave vector (wave number), and r is the position in space. For mathematical simplicity, the monochromatic plane wave in (1) is often written:   Note: Only the real part of the right side represents...

As we've seen from the article about polarization states, a light beam can be represented by its electric field vector E(r,t), which can be written: E = A cos(ωt - k • r) Being a transverse wave, the electric field vector must lie in the xy plane. So it can be decomposed into two mutually independent orthogonal components Ex and Ey: Ex = Ax cos(ωt - kz + δx)Ey = Ay cos(ωt - kz + δy) where we have used two independent and positive amplitudes Ax and Ay, and have added two independent initial phases δx and δy. Since the x component and the...

Polarized Light A polarized lightwave signal that is propagating in fiber or in free space is represented by electric and magnetic field vectors that lie at right angles to one another in a transverse plane (a plane perpendicular to light's propagation direction). Polarization is defined in terms of the pattern traced out in the transverse plane by the electric field vector as a function of time, as shown in Figure 1 below. Figure 1: Three-dimensional and "polarization ellipse" representations of polarized light These are snapshots in time, showing the electric field as a function of distance. As time passes, the...