Reply To: Absorption of materials in infrared regions

[Guilin Sun]

I am not sure what does this mean "I couldn't get absorption at a wavelength of 3um." do you get absorption at other wavelengths?

For a fixed Gaussian beam, assuming there is no side leakage, the absorption can be calculated as A=1-R-T where R is the reflection.

You can also use a less-accurate method to add a 3D monitor on the sphere, and using script to calculate the absorption power and power ratio. Please refer to this analysis group:

This less accurate method means you will need to integrate the absorbed intensity. Since it needs integration in 3D, it is is less accurate than the built-in method to calculate RT directly. But it should give you fair result compared to your experiment as experiment measurement also has some kind of errors.