RU14683U1 - OPTICAL SENSOR - Google Patents

Abstract

An optical current sensor containing a magneto-optical element made in the form of a multifaceted direct prism, on the outer surface of one of the faces of which there is a platform for entry and a platform for the exit of the light beam, and the remaining surfaces of the faces are covered with a reflective layer, and a conductor with a measured current, characterized in that the conductor with the measured current is wound along the side surface of the magneto-optical element, on the upper and lower end of which a number of protrusions are made in the form of isosceles triangles with an angle at the vertices e 90, and the vertices of the triangles on the upper end lie on a straight line with the hollows of the triangles on the lower end, and the areas for the entrance and exit of the light beam are made symmetrically at the edges on the upper or lower end of the magneto-optical element.

Description

Optical current sensor

The utility model relates to the field of magneto-optics, namely, to high-speed optoelectronic devices designed to measure electric current. It can be used in magnetometry, for transmission and processing of optical information.

A device is known that contains a magneto-optical active element with a magnetizing coil, while the magneto-optical active element has the form of a closed magnetic circuit, which is made in the form of a heptagon, one of the angles of which is 90 °, all the rest -135 °. A rectangular hole is made in the center of the heptagon, the sides of which are parallel to the four sides of the heptagon 1. The disadvantage of this device is the low sensitivity of linearly polarized light to the magnetic field, due to the short path length on which the plane of polarization of light rotates in the magnetic field of the magneto-optical active element.

A device containing a magneto-optical element having the shape of a cylinder is known. One of its bases has a cone shape with an apex angle of 90 ° 2. The disadvantage of this device is the low sensitivity of linearly polarized light to a magnetic field, which is explained by the short path length on which the plane of polarization of light rotates in the magnetic field of the proposed magneto-optical element design.

The prototype selected an optical current sensor 3 containing a magneto-optical element made in the form of a multifaceted direct prism on the outer surface of one of the faces of which there is a platform for entrance and a platform for the exit of the light beam, and the remaining surfaces of the faces are covered with a reflective layer, one of

reflective side faces radially offset relative to other reflective surfaces, and a conductor with a measured current. In the center of the magneto-optical element, a circular hole for the current conductor is made. The disadvantage of this device is the low sensitivity of linearly polarized light to a magnetic field on the way in the magneto-optical element. Indeed, in order to measure the magnitude of the electric current in conductors with diameters different from those made in the center of the hole, it is necessary to have an optical current sensor with different sizes. The interaction of the magnetic field of the conductor and the light beam in the magneto-optical material, the result of which is a change in the angle of rotation of the plane of polarization of light, does not occur along the entire length of the light path. This is due to the weakening or complete absence of a magnetic field in space at a certain distance from the conductor. Thus, the path length along which the plane of polarization of light in the magnetic field of the proposed design of the magneto-optical element is reduced is reduced.

The problem to which the utility model is directed is to increase the angle of rotation of the plane of polarization of light in the magneto-optical element when exposed to a magnetic field by increasing the optical path traveled by light in the magneto-optical element.

The problem is solved due to the fact that the optical current sensor containing the magneto-optical element is made in the form of a multifaceted direct prism, on the outer surface of one of the faces, which has an entrance area and an exit for the light beam, and the remaining surfaces of the faces are covered with a reflective layer and a conductor with measured current. Unlike the prototype, a conductor with a measured current is wound on the side surface of the magneto-optical element at the upper and lower end of which a number of protrusions are made in the form

isosceles triangles with an angle of n ° apex 90 °, and the vertices of the triangles on the upper end lie on a straight line with the hollows of the triangles on the lower end, and the areas for the entrance and exit of the light beam are made symmetrically at the edges on the upper or lower end of the magneto-optical element.

Figure 1 shows a schematic diagram of the inventive optical current sensor.

The inventive optical current sensor contains a multifaceted magneto-optical element 1, on the upper and lower end of which a number of protrusions 2 are made in the form of isosceles triangles, on the surface of which a light-reflecting layer 3 is applied; the admixtures for the input 4 and output 5 of the light beam are made symmetrically at the edges on the upper or lower end of the magneto-optical element, and a conductor with a measured current 6. The magneto-optical element 1 can be made of magneto-optical materials given in 4.

The inventive optical current sensor operates as follows.

The principle of operation of the optical current sensor is based on the Faraday magneto-optical effect 5. The increase in the sensitivity of the optical current sensor depends on the increase in the angle of rotation of the plane of polarization of linearly polarized light passing in the magneto-optical material under the influence of the magnetic field of the current conductor 5

where L is the optical path length traveled by light in a magneto-optical material; V is the Verdet constant; H is the magnetic field strength. A linearly polarized beam of light S enters the magneto-optical element 1 passing through the surface 4, passes along the path A, and falls on the reflective surface 3 at an angle of 45 ° (see figure 1). Further, a ray of light is reflected from it at an angle of 90 ° and falls at an angle of 45 °

a V Hdl / p

About j

reflecting surface B. Reflecting from it at an angle of 90 °, a ray of light along a path equal to the length of path A hits the reflecting surface C. Thus, the ray of light leaves the Faraday magneto-optical element through the exit platform 5, having traveled a path equal to 1 (1 )

The optical path length of light in the magneto-optical element is increased. Due to this, the angle of rotation of the plane of polarization of light a increases, and hence the sensitivity of the optical current sensor. The inventive optical current sensor is technologically advanced, allows measurements of the magnetic field, and is convenient in operation.

Claim

An optical current sensor containing a magneto-optical element made in the form of a multifaceted direct prism on the outer surface of one of the faces of which there is a platform for entrance and a platform for the exit of the light beam, and the remaining surfaces of the faces are covered with a reflective layer and a conductor with a measured current characterized in that the conductor with measured current is wound on the side surface of the magneto-optical element, on the upper and lower end of which a number of protrusions are made in the form of isosceles triangles with an angle at the apex 90 °, and the vertices of the triangles on the upper end lie on a straight line with the hollows of the triangles on the lower end, and the areas for the entrance and exit of the light beam are made symmetrically at the edges on the upper or lower end of the magneto-optical element.

Sources of information

1. The author's certificate of the USSR No. 1337868, cl. G 02 F 1/09, 1971.

2.US Patent No. 5,523,373, cl. G 01 R 31/00, 1996.

3. German patent No. 434209, cl. G 01 R 19/00, 1995. - Prototype.

4. Elements and devices on cylindrical magnetic domains: Reference / A.M. Balbashov, F.V. Lisovsky, V.K. Raev et al .; Ed. N.P. Evtikhieva B.P. Paumova. - M .: Radio and communications, 1987. - 488 p.: Ill.

5.Busurin V.I., Nosov Yu.R. Fiber Optic Sensors: Physical Basics, Calculation and Application Issues. - M.: Energoatomizdat, 1990 .-- 256 p.: Ill.

Claims (1)

An optical current sensor containing a magneto-optical element made in the form of a multifaceted direct prism, on the outer surface of one of the faces of which there is a platform for entry and a platform for the exit of the light beam, and the remaining surfaces of the faces are covered with a reflective layer, and a conductor with a measured current, characterized in that the conductor with the measured current is wound along the lateral surface of the magneto-optical element, on the upper and lower end of which a number of protrusions are made in the form of isosceles triangles with an angle at the vertices e 90 ^o , and the vertices of the triangles on the upper end lie on a straight line with the hollows of the triangles on the lower end, and the areas for the entrance and exit of the light beam are made symmetrically at the edges on the upper or lower end of the magneto-optical element.