Module polarization::jones

Polarization simulations using Jones calculus.

Jones calculus represents the components of an electric field (its polarization) as a 2x1 column vector (a Jones vector), and the effects of optical elements as 2x2 matrices (Jones matrices). The final polarization is found by multiplying the Jones vector of the beam by the Jones matrices of all the optical elements that the beam passes through. In general, both Jones vectors and Jones matrices are complex (have imaginary components), where the imaginary parts encode the phase of each component.

Conventions

This is physics, so of course there are going to be some conventions.

Axes

The beam propagates in the +z-direction. This means that the polarization of the beam lives in the xy-plane.

Angles

All angles are measured counter-clockwise from the x-axis.

Overview

A basic polarization simulation involves just a few steps:

• Create a beam
• Create some optical elements
• Create an OpticalSystem
• Add the beam and the elements to the OpticalSystem
• Call propagate to send the beam through the elements

Elements

There are several standard optical elements defined by the jones module:

• linear polarizer (Polarizer)
• half-wave plate (HalfWavePlate)
• quarter-wave plate (QuarterWavePlate)
• retarder (Retarder)
• polarization rotator (PolarizationRotator)

Support for reflections from a dielectric or metal surface will be added in the near future.

What if you want to use an optical element type that isn't included in this library? There is a slight hack that will let you do this. There is an element type called CompositeElement that is used to represent the effects of several elements with a single Jones matrix. This element type is constructed from a user-supplied matrix. If you can create the matrix for your custom element, then you can wrap it in a CompositeElement and use it in a simulation.

Beams

A beam can be constructed in a number of ways. There are convenience methods for defining common polarization states:

• linearly polarized -> Beam::linear
• circularly polarized -> Beam::circular

You may also construct an arbitrary beam using Beam::new.

Optical System

An optical system is the construct that performs the simulation. To perform a simulation, you must add a beam and some elements to the optical system, then call propagate.

let beam = Beam::linear(Angle::Degrees(0.0));
let pol = OpticalElement::Polarizer(Polarizer::new(Angle::Degrees(45.0)));
let system = OpticalSystem::new()
    .add_beam(beam)
    .add_element(pol);
let final_beam: Result<Beam> = system.propagate();

If you add multiple elements to the optical system, the beam will travel through them in the order that they are added to the optical system.

Re-exports

pub use self::common::*;

pub use self::composite::*;

pub use self::hwp::*;

pub use self::identity::*;

pub use self::polarizer::*;

pub use self::qwp::*;

pub use self::retarder::*;

pub use self::rotator::*;

pub use self::system::*;

Modules

common	Types and definitions used in other modules.
composite	Implementation of an element that composes several other elements.
hwp	A half-wave plate.
identity	An element that has no effect.
polarizer	A linear polarizer.
qwp	A quarter-wave plate.
retarder	An optical retarder.
rotator	A polarization rotator.
system	An optical system that encapsulates a beam and the elements that it will pass through.