Optical Propagation

A library of useful optical propagation methods.

Many extracted from the book by Schmidt, 2010: Numerical Methods of optical proagation

aotools.opticalpropagation.angularSpectrum(inputComplexAmp, wvl, inputSpacing, outputSpacing, z)

Propogates light complex amplitude using an angular spectrum algorithm

Parameters:

• inputComplexAmp (ndarray) – Complex array of input complex amplitude
• wvl (float) – Wavelength of light to propagate
• inputSpacing (float) – The spacing between points on the input array in metres
• outputSpacing (float) – The desired spacing between points on the output array in metres
• z (float) – Distance to propagate in metres

Returns:

propagated complex amplitude

Return type:

ndarray

aotools.opticalpropagation.lensAgainst(Uin, wvl, d1, f)

Propagates from the pupil plane to the focal plane for an object placed against (and just before) a lens.

Parameters:

• Uin (ndarray) – Input complex amplitude
• wvl (float) – Wavelength of light in metres
• d1 (float) – spacing of input plane
• f (float) – Focal length of lens

Returns:

Output complex amplitude

Return type:

ndarray

aotools.opticalpropagation.oneStepFresnel(Uin, wvl, d1, z)

Fresnel propagation using a one step Fresnel propagation method.

Parameters:

• Uin (ndarray) – A 2-d, complex, input array of complex amplitude
• wvl (float) – Wavelength of propagated light in metres
• d1 (float) – spacing of input plane
• z (float) – metres to propagate along optical axis

Returns:

Complex ampltitude after propagation

Return type:

ndarray

aotools.opticalpropagation.twoStepFresnel(Uin, wvl, d1, d2, z)

Fresnel propagation using a two step Fresnel propagation method.

Parameters:

• Uin (ndarray) – A 2-d, complex, input array of complex amplitude
• wvl (float) – Wavelength of propagated light in metres
• d1 (float) – spacing of input plane
• d2 (float) – desired output array spacing
• z (float) – metres to propagate along optical axis

Returns:

Complex ampltitude after propagation

Return type:

ndarray