pygrin.pygrin Module

Gradient Index lens calculations and plots.

More documentation at <>

Typical usage:

import pygin

length = 7               # mm
diameter = 2             # mm
r = np.linspace(-1,1,11) # mm
n_0 = 1.48               # refractive index at r=0
theta_i = 0              # launch angle
pitch = 0.25             # quarter pitch lens

pygrin.plot_principal_planes(n_0, pitch, length, diameter)
for r_i in r:
    z,r = pygrin.meridional_curve(n_0, pitch, length, r_i, theta_i)

Functions to locate focal points and cardinal points:

BFL(n_0, pitch, length)
EFL(n_0, pitch, length)
FFL(n_0, pitch, length)
NA(n_0, pitch, length, diameter)
cardinal_points(n_0, pitch, length)

Functions to find properties of GRIN lens:

gradient(pitch, length)
period(grad, length)
max_angle(n_0, pitch, length, diameter)
ABCD(n_0, pitch, length, z)
image_distance(n_0, pitch, length, s)
image_mag(n_0, pitch, length, s)

Functions to determine refractive index profile:

hyperbolic_secant_profile_index(n_0, alpha, r)
parabolic_profile_index(n_0, pitch, length, r)

Functions to help raytrace through GRIN lens:

full_meridional_curve(n_0, pitch, length, z_obj, r_obj, r_lens)
meridional_curve(n_0, pitch, length, r_i, theta_i)
plot_principal_planes(n_0, pitch, length, diameter)


ABCD(n_0, pitch, length, z)

ABCD matrix for meridonal ray propagation.

BFL(n_0, pitch, length)

Back focal length of a grin lens.

EFL(n_0, pitch, length)

Effective focal length of a grin lens.

FFL(n_0, pitch, length)

Front focal length of a grin lens.

NA(n_0, pitch, length, diameter)

Numerical aperture of a grin lens in air.

cardinal_points(n_0, pitch, length[, offset])

Cardinal points of a grin lens relative to first surface.

full_meridional_curve(n_0, pitch, length, ...)

Points on a path from an object to image through a GRIN lens.

gradient(pitch, length)

Gradient of a grin lens based on its pitch and length.

hyperbolic_secant_profile_index(n_0, alpha, r)

Index of a hyperbolic secant grin lens at a particular radius.

image_distance(n_0, pitch, length, s)

Image distance for an object.

image_mag(n_0, pitch, length, s)

Transverse magnification of an object located at s.

max_angle(n_0, pitch, length, diameter)

Maximum acceptance angle of a grin lens in air.

meridional_curve(n_0, pitch, length, r_i, ...)

Points on path of a ray passing through a grin lens.

parabolic_profile_index(n_0, pitch, length, r)

Index of a parabolic grin lens at a particular radius.

period(grad, length)

Period or pitch of a grin lens based on its gradient and length.

plot_principal_planes(n_0, pitch, length, ...)

Create a plot for a grin lens showing the cardinal points.