Optical Fiber Communications 4th Edition by Gerd Keiser

Exercise 18

Using Eqs. (5.19) and (5.20), show that Eq. (5.36) gives the coupling loss for two fibers with unequal axial numerical apertures. Plot this coupling loss in decibels as a function of NA R (0)/NA E (0) over the range 0.5 NA R (0)/NA E (0) 1.0.