colour.contrast.pupil_diameter_Barten1999#

colour.contrast.pupil_diameter_Barten1999(L: FloatingOrArrayLike, X_0: FloatingOrArrayLike = 60, Y_0: FloatingOrArrayLike | None = None) → FloatingOrNDArray[source]#

Return the pupil diameter for given luminance and object or stimulus angular size using Barten (1999) method.

Parameters:

  • L (FloatingOrArrayLike) – Average luminance \(L\) in \(cd/m^2\).

  • X_0 (FloatingOrArrayLike) – Angular size of the object \(X_0\) in degrees in the x direction.

  • Y_0 (FloatingOrArrayLike | None) – Angular size of the object \(X_0\) in degrees in the y direction.

Returns:

Pupil diameter.

Return type:

numpy.floating or numpy.ndarray

References

[Bar99], [Bar03], [CKMW04], [InternationalTUnion15c], [WY12]

Notes

  • The Log function is using base 10 as indicated by [WY12].

Examples

>>> pupil_diameter_Barten1999(100, 60, 60)  
2.7931307...