Sphere

class iadpython.sphere.Sphere(d_sphere, d_sample, d_entrance=0, d_detector=0, r_detector=0, r_wall=0.99, r_std=0.99)[source]

Bases: object

Container class for an integrating sphere.

- d_sphere: diameter of integrating sphere [mm]

- d_sample: diameter of the sample port [mm]

- d_entrance: diameter of the port that light enters the sphere [mm]

- d_detector: diameter of the detector port [mm]

- r_detector: reflectivity of the detector

- r_wall: reflectivity of the wall

- r_std: reflectivity of the standard used with the sphere

Example:

>>> import iadpython as iad
>>> s = iad.Sphere(200, 20)
>>> print(s)

Attributes Summary

`a_wall`	Getter property for detector port diameter.
`d_detector`	Getter property for detector port diameter.
`d_entrance`	Getter property for entrance port diameter.
`d_sample`	Getter property for sample port diameter.
`d_sphere`	Getter property for sphere diameter.
`r_std`	Getter property for reflectance standard.
`r_wall`	Getter property for wall reflectivity.

Methods Summary

`approx_relative_cap_area`(d_port)	Calculate approx relative area of spherical cap.
`cap_area`(d_port)	Calculate area of spherical cap.
`gain`(URU[, r_wall])	Determine the gain relative to a black sphere.
`multiplier`([UR1, URU, r_wall])	Determine the average reflectance of a sphere.
`relative_cap_area`(d_port)	Calculate relative area of spherical cap.

Attributes Documentation

a_wall: Getter property for detector port diameter.

d_detector: Getter property for detector port diameter.

d_entrance: Getter property for entrance port diameter.

d_sample: Getter property for sample port diameter.

d_sphere: Getter property for sphere diameter.

r_std: Getter property for reflectance standard.

r_wall: Getter property for wall reflectivity.

Methods Documentation

approx_relative_cap_area(d_port)[source]: Calculate approx relative area of spherical cap.

cap_area(d_port)[source]: Calculate area of spherical cap.

gain(URU, r_wall=None)[source]

Determine the gain relative to a black sphere.

If the walls of the sphere are black then the light falling on the detector is the diffuse light entering the sphere divided by the surface area on the sphere (P/A).

If the walls are perfectly white (and ports are perfectly absorbing) then all the entering light exits through the ports. (P/A_ports)

The gain caused by 0% reflecting sphere walls (no port refl) is

\[\mbox{gain} = \frac{(P/A)}{(P/A)} = 1\]

The gain caused by 100% reflecting sphere walls (no port refl) is

\[\mbox{gain} = \frac{(P/A_ports)}{(P/A)} = \frac{A_total}{A_ports}\]

Parameters:

URU – reflectance from sample port for diffuse light
r_wall – wall reflectance

Returns:

gain on detector caused by bounces inside sphere

multiplier(UR1=None, URU=None, r_wall=None)[source]

Determine the average reflectance of a sphere.

The idea here is that UR1 is the reflection of the incident light for the first bounce. Three cases come to mind

1. If the light hits the sample first, then UR1 should be the sample reflectance for collimated illumination.

2. If light hits the sphere wall first, then UR1 should be the wall reflectance.

If light is enters the sphere completely diffuse then UR1=1

As defined by LabSphere, “Technical Guide: integrating Sphere Theory and application” using equation 14

Parameters:

UR1 – sample reflectance for normal collimated irradiance
URU – sample reflectance for diffuse irradiance
r_wall – wall reflectance

Returns:

sphere multiplier

relative_cap_area(d_port)[source]: Calculate relative area of spherical cap.