TRANSMISSION LINE EQUATION IN TERMS OF IMPEDANCE 265 



Dr. L. A. MacCoU has pointed out to the writer that (2) is the same as 

 the electrostatic electron optical equation for paraxial rays. To reduce (2) 

 to the standard form: 



-R' = Hiz) (7) 



^ = II(z) + Z' (8) 



az 



The electron optical equation for paraxial rays is 



Here z is distance along the axis, V{z) is potential on the axis, and C is 

 convergence, or the inverse of the focal distance. 



It would seem, then, that from each solution of an electron optical 

 problem, a solution of a tapered line problem could be found, and vice versa. 



While it cannot be claimed that anything new has entered the transmis- 

 sion line equation in expressing it in terms of impedance, it does seem that 

 the approach may be stimulating in uncovering hitherto neglected material 

 and analogies. 



