SU995034A1 - Device for measuring pulse magnetic field strength - Google Patents

Description

 (Sk) DEVICE FOR MEASURING THE TENSION OF A PULSE MAGNETIC FIELD

one

This invention relates to a magnetometer) and is intended to measure the strength of the magnetic component of an electromagnetic pulse.

A device for measuring a magnetic field is known, which contains a high-frequency geyrator, a receiver made in the form of a detector, a recording device and a ferrite core. The device is equipped with a modulator, a horn radiator and an inclined semitransparent mirror. However, the horn of the receiving path is influenced by the electric field, which distorts the measurement of the magnetic field under the influence of an electromagnetic pulse.

1 the closest to the invention is a magnetic field sensor, consisting of a light-tight case, an illuminator, a frame with quartz extensions on which the transmitter elements are suspended — a magnet with fixed

on it is a polarization filter and a balance bar. The stationary polarization filter is placed in the housing of the light receiver, which, in turn, is fixed in the sensor housing with the aid of a sleeve. The photoresistance of the light receiver is electrically connected to the bridge circuit, the diagonal of which includes an indicator.

Claims (2)

When measuring the outer field, the mait turns on stretch. Together with the magnet, the polarization filter is rotated relative to the fixed filter. This alters the photoresistance of the photoreceiver. The change in the resistance of the latter causes imbalance of the bridge and the appearance of the output signal detected by the 2J indicator. However, a known sensor works only in the absence of mechanical oscillations, since they cause the magnet to move and cause a 3 s error in the measurement. . In addition, the driver is able to respond mainly to the action of low-frequency magnetic fields due to the relatively large inertia of the sensitive element. The purpose of the invention is to increase the reliability of measurements under the influence of mechanical oscillations and to expand the frequency range of measured signals. The goal is achieved by the device for measuring the intensity of a pulsed magnetic field containing an illuminator, transmitter, light receiver and a recording device, the input of which is connected to the output of the light receiver, the transmitter is made in the form of an acousto-optic cell combined with a magnetoacoustic transducer, with the input and output of the acousto-optic cell connected Recorded respectively with the output of the illuminator and the input of the receiver board. In addition, the acousto-optic cell has the shape of a parallelepiped, while the acousto-optic cell, the illuminator and the light receiver are connected using fiberglass optical communication lines. The drawing shows a block diagram of the device. The device contains an illuminator 1, which uses an optical quantum generator, a transmitter including a magnetoacoustic transducer 2 and an acousto-optic cell 3, a light receiver 4, a recording device 5 and fiber-optic communication lines 6. The optical quantum generator, photodetector, and recorder are located outside the field of action of the recorded pulsed magnetic field and placed in an electromagnetic screen. The device is based on the phenomenon of light diffraction by ultrasound. In order to increase the diffraction efficiency of light on ultrasound, the acoustic interaction geometry is provided so that light falls on the sound beam at the Bragg angle, which is especially important for diffraction of light on high-frequency sound (100 MHz), while the Bragg angle is determined from the expression. V-yr OB Bragg angle; where CL is the ultrasound velocity in the acousto-optic cell material; L is the wavelength of the light passing through the acousto-optic cell; f is the frequency of ultrasonic vibrations. This takes into account the final divergence of both the light and acoustic beams, which is characterized by the values of -B.og - L and aq. where X is the wavelength of light; L is the ultrasound wavelength; d is the characteristic size of the light; D is the characteristic size of the acousto-optic cell. The device works as follows. When a pulsed magnetic field is applied to a magnetoacoustic transducer 2, the magnetic field oscillations are converted into an ultrasonic wave, which, passing through the acousto-optic cell 3, controls the intensity of the light beam emitted by the illuminator 1 and passing through the acousto-optic cell 3.. The intensity-modulated light beam enters the light receiver, in which the light signal is converted into an electrical one. From the output of the receiver k of the light, the electric signal is fed to the input of the recording device 5. Compared with the known, the proposed device has a wider frequency range of measured signals, which is a consequence of a decrease in the inertia of the transmitter elements, as well as the mechanical vibrations of the device do not affect the measurement results and the transmitter mechanical strength is increased. The invention provides a measurement of a pulsed magnetic field of 1-105 A / m with a frequency range of 10-10 Hz. Claims. 1. Device for measuring 1; pulse magnetic field. 59 containing an illuminator, a transmitter, a light receiver and a recording device, the input of which is connected to the output of the light receiver, which is in order to increase the accuracy of measurements under the influence of mechanical vibrations and extend the frequency range of the measurements Signals, the transmitter is made in the form of an acousto-optic cell articulated with a magnetoacoustic transducer, and the input and output of the acousto-optic cell are connected respectively with the output of the illuminator and the input of the light receiver. J / fftff // fc / rref 6/3 2. The device according to claim 1 is based on the fact that the acousto-optic cell has the shape of a parallelepiped, and the connection of the acousto-optic cell, the illuminator and the light receiver is made using glass fiber optics - sie lines of communication. Sources and (“|) Formats taken into account in the examination 1. USSR author's certificate No. 713829, cl. G 01 R 33/02, 1977. 2. Authors certificate of the USSR (R 69105, class G 01 R 33/02, 1973 (prototype).