AC AND DC OPTICAL LABORATORY METER Russian patent published in 2020 - IPC G01R15/24 

FIELD: optics; instrument engineering.

SUBSTANCE: invention relates to optical devices using a Faraday effect for measuring electric current. Disclosed device comprises a light source, a first polariser, a quadrangular glass prism with height h, on its first base an additional prism is fixed and a mirror coating is applied, second prism base comprises two polished surfaces with mirror coatings, which are inclined relative to the first base at equal angles γ=arctg(0.5D/h) and make a rib between themselves at the center. Further, along the beam path there is a second polariser in the form of a Wollaston prism with planes of polarization of rays separated by it at angles of ±45 degrees relative to the transmission plane of the first polariser, lenses, photodetectors and an electronic unit. On the first base there is a mirror coating, which occupies 2/3 of its surface, the line of separation between the clean and mirror surfaces is parallel to the rib of the second base of the quadrangular prism. Additional prism is glued to the clean surface of the first base so that its rib is perpendicular to the quadrangular prism rib, and its polished faces are inclined to its base at angles θ=arcsin{n_λsin[arctg(0.5l/L)]}, where n _λ is refraction index of additional prism glass for wavelength of λ light source; l is the distance between the centers of light entering the prism and emerging from it; L is path length of light beam in both prisms. Solenoid embraces a quadrangular prism along its entire height and is made in the form of a set of separate flat multilayer coils identical to the inner diameter from winding conductors laid in layers on each other and interconnected in parallel. Turns form coils containing one to four multilayer turns and connected to each other in parallel when measuring high currents or in series when measuring low currents.

EFFECT: wider range of measurements.

1 cl, 11 dwg