Abstract: A measurement probe that measures a change in an optical signal caused by electro-optic effect according to an electromagnetic wave, and measures spatial distribution characteristics of the electromagnetic wave, based on differential values detected while the measurement probe and the electromagnetic wave move relative to each other. The measurement probe includes a first measurement device having a sensor structure including an electro-optic crystal that exhibits the electro-optic effect, an optical fiber that is provided on a root side of the electro-optic crystal and transmits the optical signal, and a reflection device that is provided on a tip end side of the electro-optic crystal and reflects the optical signal, and a second measurement device having the sensor structure. In first and second directions perpendicular to a fiber axis direction, a size of the electro-optic crystal is set to one third or less of a wavelength of the target electromagnetic wave.

Abstract: A measurement probe used in an electromagnetic wave measurement system is provided. The measurement probe includes a first measurement device and a second measurement device. The first measurement device includes a first electro-optic crystal that exhibits an electro-optic effect, a first optical fiber that is provided on a root side of the first electro-optic crystal and transmits an optical signal, and a first reflector that is provided on a tip side of the first electro-optic crystal and reflects the optical signal. The second measurement device includes a second electro-optic crystal, a second optical fiber, and a second reflector. The first and second electro-optic crystals form one electro-optic crystal, and the first and second optical fibers are connected to a root side of the one electro-optic crystal.

Abstract: The ability to estimate a filter clog by a means other than measuring fluid pressure is presented. The filter monitoring system of the present disclosure comprises a vibration data transmission unit, which is mounted on a filtration device, detecting filter vibrations associated with the operation of filtration device described above, sending such as vibration data, and a clog estimation unit, which detects the phenomenon of declining vibration value caused by a filter clog, estimating the degree of blockage for the filter described above.