F = (1/4)(n2/n1)2[1-{(n1-n2)/(n1+n2)}2] ?

[Huiling]

Hi，I was wondering if someone could tell me the name of this equation, where does the equation come from?
“If light is isotropically generated in a medium then the fraction transmitted to the outside world is given by:
F = (1/4)(n2/n1)2[1-{(n1-n2)/(n1+n2)}2]”

Thank you so much :)

 

[Simon Bridge]

Welcome to PF;
Where did you find the equation?
Something to do with LEDs?

It looks like a transmission coefficient or optical efficiency relation... it probably does not have a special name: most equations don't. Why does it matter what an equation is called?

 

[Huiling]

Hi, it's about LED. I saw this equation somewhere, I can't remember where, but I thought I would look into it so I can understand it and maybe read a bit more about it. Thanks