DETECTOR FOR NMR

PURPOSE:To observe a part to be observed for a lone time by a method wherein an NMR antenna is inserted and mounted in vivo to lead an NMR signal received in vivo and the NMR signal is transmitted to an NMR observing device to obtain a detailed NMR image even at a part to be observed which makes an endoscope hard to insert. CONSTITUTION:An NMR antenna 25 is connected to a terminal 31 in vivo via a signal transmission line 28 such as coaxial cable through an impedance matching device 29. A membrane 32 compatible with an organism is covered watertight together with the impedance matching device 29 and has a fixing hole 33 at a rim part thereof to be mounted to be fixed on a part 26 to be observed with a thread 34 for stitching. An external terminal 27 is retained on the terminal 31 in vivo and an electrode 40 projected on a bottom surface of an opening 39 is connected to an electrode 36 electrically. The NMR antenna 25 mounted on the part 26 to be observed receives and transmits an NMR signal to a controller 8 through a lead 35, the electrode 36, the electrode 40, a lead 41 and a harmonic receiver 12.