colour.sd_mesopic_luminous_efficiency_function#

colour.sd_mesopic_luminous_efficiency_function(L_p: float, source: Literal['Blue Heavy', 'Red Heavy'] | str = 'Blue Heavy', method: Literal['MOVE', 'LRC'] | str = 'MOVE', photopic_lef: SpectralDistribution | None = None, scotopic_lef: SpectralDistribution | None = None) → SpectralDistribution[source]#

Return the mesopic luminous efficiency function \(V_m(\lambda)\) for the specified photopic luminance \(L_p\).

Parameters:

  • L_p (float) – Photopic luminance \(L_p\).

  • source (Literal['Blue Heavy', 'Red Heavy'] | str) – Light source colour temperature.

  • method (Literal['MOVE', 'LRC'] | str) – Method to calculate the weighting factor.

  • photopic_lef (SpectralDistribution | None) – \(V(\lambda)\) photopic luminous efficiency function, default to the CIE 1924 Photopic Standard Observer.

  • scotopic_lef (SpectralDistribution | None) – \(V^\prime(\lambda)\) scotopic luminous efficiency function, default to the CIE 1951 Scotopic Standard Observer.

Returns:

Mesopic luminous efficiency function \(V_m(\lambda)\).

Return type:

colour.SpectralDistribution

References

[Wikipedia05c]

Examples

>>> sd = sd_mesopic_luminous_efficiency_function(0.2)
>>> sd.shape
SpectralShape(380.0, 780.0, 1.0)
>>> sd[500]
np.float64(0.8352251...)