Miniature optically pumped magnetometer probe using light pipes to transmit light to the probe

Claim 1

A magnetometer based on the principle of optical pumping comprising a cell filled with atomic vapor, a light source, means for transmitting the light emitted by the light source to said cell, means for exciting the vapor contained in the cell through a high frequency signal including a coil surrounding the cell and an r.f. generator connected to said coil, means for measuring the extent of excitation of said cell including a photocell responsive to the light penetrating said cell and an indicating device connected to said photocell, characterized in that said cell, said coil and said photocell are disposed in a housing of small volume to form a probe, whereas said r.f. generator, said indicating device and said light source are disposed in a device remote from said probe, said coil and said photocell being connected to said r.f. generator and said indicating device, respectively, by plural lines, said means for transmitting the light emitted by said light source to said cell being provided in the form of a flexible light conductor extending from said light source to said cell, wherein said probe further comprises a prism arranged between the end of the light conductor and the cell for deflecting the beam emanating from the light conductor onto the cell, a polarizer and a quarter wave plate disposed in the path of the rays between the prism and the cell, and a heater surrounding said cell.