# colour.sd_blackbody#

colour.sd_blackbody(temperature: float, shape: SpectralShape = SPECTRAL_SHAPE_DEFAULT, c1: float = CONSTANT_C1, c2: float = CONSTANT_C2, n: float = CONSTANT_N) [source]#

Return the spectral distribution of the planckian radiator for given temperature $$T[K]$$ with values in watts per steradian per square metre per nanometer ($$W/sr/m^2/nm$$).

Parameters:
• temperature (float) – Temperature $$T[K]$$ in kelvin degrees.

• shape (SpectralShape) – Spectral shape used to create the spectral distribution of the planckian radiator.

• c1 (float) – The official value of $$c1$$ is provided by the Committee on Data for Science and Technology (CODATA) and is $$c1=3,741771x10.16\ W/m_2$$ (Mohr and Taylor, 2000).

• c2 (float) – Since $$T$$ is measured on the International Temperature Scale, the value of $$c2$$ used in colorimetry should follow that adopted in the current International Temperature Scale (ITS-90) (Preston-Thomas, 1990; Mielenz et aI., 1991), namely $$c2=1,4388x10.2\ m/K$$.

• n (float) – Medium index of refraction. For dry air at 15C and 101 325 Pa, containing 0,03 percent by volume of carbon dioxide, it is approximately 1,00028 throughout the visible region although CIE 15:2004 recommends using $$n=1$$.

Returns:

Blackbody spectral distribution with values in watts per steradian per square metre per nanometer ($$W/sr/m^2/nm$$).

Return type:

colour.SpectralDistribution

Examples

>>> from colour.utilities import numpy_print_options
>>> with numpy_print_options(suppress=True):
...     sd_blackbody(5000, shape=SpectralShape(400, 700, 20))
...
...
SpectralDistribution([[   400.        ,   8742.5713329...],
[   420.        ,   9651.6810212...],
[   440.        ,  10447.3423137...],
[   460.        ,  11121.8597759...],
[   480.        ,  11673.7121534...],
[   500.        ,  12106.0645344...],
[   520.        ,  12425.4166118...],
[   540.        ,  12640.4550541...],
[   560.        ,  12761.1284859...],
[   580.        ,  12797.9345572...],
[   600.        ,  12761.3938171...],
[   620.        ,  12661.6795247...],
[   640.        ,  12508.3723863...],
[   660.        ,  12310.3119640...],
[   680.        ,  12075.5205176...],
[   700.        ,  11811.1793602...]],
SpragueInterpolator,
{},
Extrapolator,
{'method': 'Constant', 'left': None, 'right': None})