Variables
Description
What is this formula?
The absorption transmittance formula describes how light intensity decreases as it travels through an absorbing material. It is based on the Beer-Lambert law and relates transmitted intensity to material thickness and absorption coefficient.
When to use it
Use this formula when studying light attenuation in transparent or semi-transparent materials such as glass, liquids, optical filters, biological tissue, and atmospheric media.
Example
A laser beam passes through a material with an absorption coefficient of 0.8 m⁻¹ and thickness of 2 m.
Data:
alpha = 0.8 m⁻¹
x = 2 m
Formula:
T = e^(-alpha*x)
Substitution:
T = e^(-0.8*2)
Result:
T ≈ 0.202
Approximately 20.2% of the incident light is transmitted through the material.
Applications
Optical filters, spectroscopy, laser attenuation, atmospheric optics, biomedical imaging, material characterization, and photonics.