Some relations for cavities

Cavity Enhancement with absorption losses input coupler and absorption losses in the cavity

The enhancement U is calculated by

U=(1-IC-AIC)/(1-sqrt(R^N*IC*T))^2

(All parameters are related to the power and not to the field)

Reflectivity input coupler IC 
Absorption input coupler AIC 
Reflectivity other mirrors R  
Number of reflections other mirrors N  
Transparency medium  T 

Enhancement 

Cavity finesse with absorption losses in the cavity

The finesse F is calculated by

F=pi*sqrt(sqrt(R^N*IC*T))/(1-sqrt(R^N*IC*T))

(All parameters are related to the power and not to the field)


Finesse 

Mode jumping of a doubling cavity (410 nm -> 205 nm)