Abstract: An object of the present invention is to provide a technique to improve a manufacturing yield of a gas cell included in a magnetic field measuring apparatus. A gas cell GC according to an embodiment is characterized in that, for example, a cavity CAV includes an opening OP1 and an opening OP2, a plane size of the opening OP1 becomes larger than a plane size of the opening OP2 in the openings OP1 and OP2 included in the cavity CAV. Especially, according to the embodiment, the opening OP2 is included in the opening OP1 in plan view. Consequently, a width of the opening OP1 coming into contact with an upper surface of the sealing substrate 1S becomes larger than a width of the opening OP2 coming into contact with a lower surface of the sealing substrate 2S.

Abstract: Stable magnetic field measurement is enabled without collapse of polarization or fluctuation of intensity of a laser beam incident on a glass cell of an optical pumping magnetic sensor. Excitation light generated with a light source, having optimized light intensity and polarized wave, through frequency stabilization, intensity control and polarized-wave control, is introduced via a polarized wave holding optical fiber to a magnetic sensor provided in a magnetic shield, and magnetic field measurement is performed by optical pumping using magneto-optical properties of spin-polarized alkali metal. The magnetic sensor has a structure where a lens, a polarization optical device, the glass cell and a photodetector, are integrally accommodated in a non-magnetic case.

Abstract: In order to provide a magnetic field measuring apparatus facilitating the pressure control in a gas cell, or capable of inspecting the internal pressure of the gas cell without using any special process, the magnetic field measuring apparatus is configured such that a process layer of the magnetic field measuring apparatus has such a structure that includes a first hollow portion and a second hollow portion provided opposed to first hollow portion with a first isolation wall interposed therebetween. Alternatively, a method for manufacturing the magnetic field measuring apparatus includes breaking the first isolation wall after generating alkali metal (FIG. 17 and FIG. 20).

Abstract: In order to provide a magnetic field measuring apparatus facilitating the pressure control in a gas cell, or capable of inspecting the internal pressure of the gas cell without using any special process, the magnetic field measuring apparatus is configured such that a process layer of the magnetic field measuring apparatus has such a structure that includes a first hollow portion and a second hollow portion provided opposed to first hollow portion with a first isolation wall interposed therebetween. Alternatively, a method for manufacturing the magnetic field measuring apparatus includes breaking the first isolation wall after generating alkali metal (FIG. 17 and FIG. 20).

Abstract: Stable magnetic field measurement is enabled without collapse of polarization or fluctuation of intensity of a laser beam incident on a glass cell of an optical pumping magnetic sensor. Excitation light generated with a light source, having optimized light intensity and polarized wave, through frequency stabilization, intensity control and polarized-wave control, is introduced via a polarized wave holding optical fiber to a magnetic sensor provided in a magnetic shield, and magnetic field measurement is performed by optical pumping using magneto-optical properties of spin-polarized alkali metal. The magnetic sensor has a structure where a lens, a polarization optical device, the glass cell and a photodetector, are integrally accommodated in a non-magnetic case.