absorptance

Absorptance is the ratio of the radiation absorbed by a surface to that incident upon it.

Figure shows the relationship between reflectance, absorptance and transmittance.

"The action spectrum, absorptance and quantum yield of photosynthesis in crop plants".

The corresponding quantities are called the reflectance,absorptance and transmittance of the canopy.

In science, the term absorptivity (or absorptance) may refer to:

Absorptance refers to a directly proportional ratio.

Same as Absorptance.

Absorptance is a simple ratio, whereas absorbance is a logarithmic ratio.

In physics, the term spectral absorbance is used interchangeably with spectral absorptance or absorptivity.

Total absorptance refers to absorptance measured over all wavelengths.

Spectral absorptance refers to absorptance measured at a specified wavelengths.

The terms visible transmittance (VT) and visible absorptance (VA), which are the respective fractions for the spectrum of light visible radiation, are also used.

A mnemonic to remember the difference between absorbance and absorptance is that absorbance has no t, or not t, meaning it measures all that is not transmitted.

You must consider the absorptance of the glass and the film, the size of the pane, the thickness of the glass, the construction of the window - is it single pane, insulated glass, treated (with a low-emissivity coating), laminated or toughened?