Embodiments of the present invention provide devices and methods for treating various target sites. The first receiver module is operable to convert a received optical signal to an electrical signal. A tip having converging sides that create a point extends from the shoulders. A difference between the off-set of the first straight line and the off-set of the second straight line is used in determining registration errors. The RFID antenna has a limited reading range. The advantage of removing the electric fields from the weaker dielectric region to a stronger area improves reliability, increases component life and operating levels, reduces noise and losses, and allows for a smaller compact design.