Patent ID: 7701212

Claim:
A low temperature probe having a transmitting coil and a receiving coil or a transmit/receive coil, and used in an NMR apparatus, comprising: an opposed heat exchanger cooling a cooling medium at a room temperature to no more than a predetermined temperature in one side; a cooling apparatus structured by connecting at least two refrigerating machines having two stages in series, and cooling the cooling medium from said opposed heat exchanger, said two cooling stages having a first cooling stage capable of cooling to no more than 10K and a second cooling stage capable of cooling to at least 10K; a probe portion having a first heat exchanging portion executing a heat exchange between the cooling medium from said cooling apparatus and said receiving coil or said transmit/receive coil; and a circulation structure circulating the cooling medium from said probe portion into an other side of said opposed heat exchanger; wherein said probe portion is provided with a second heat exchanging portion executing a heat exchange between the cooling medium from said first heat exchanging portion and a heat radiation shield disposed with respect to the cooling medium from said first heat exchanging portion and said receiving coil or said transmit/receive coil, and the cooling medium from said second heat exchanging portion being circulated into the other side of said opposed heat exchanger; wherein said first and second heat exchanging portions are disposed within said heat radiation shield; wherein said first heat exchanging portion and said receiving coil or said transmit/receive coil are thermally connected by a heat conduction portion of at least one of aluminum nitride and sapphire; and wherein said heat radiation shield has a heat capacity greater than the heat capacity of the cooling medium.