# US 2022/0034945 A1 · Monolithic glass ring and method for optical current measurements > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2022/0034945 A1 - Document ID: US20220034945A1 - Status: Published application - Kind: A1 - Application number: 17/280,338 - Filed: 2019-09-06 - Published: 2022-02-03 - Earliest claimed: 2018-09-26 - Assignees: Siemens Energy Global GmbH & Co. KG - Applicants: Siemens Energy Global GmbH & Co. KG - Inventors: STEFAN SCHUBERTH - Web page: https://patentgrep.com/patent/US20220034945A1 ## CPC - G01R 15/246: {based on the Faraday, i.e. linear magneto-optic, effect} - G01R 15/247: {Details of the circuitry or construction of devices covered by G01R15/241 - G01R15/246} - G01R 19/0092: {Measuring current only} - G02B 6/00: Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings - G02F 1/0136: {for the control of polarisation, e.g. state of polarisation [SOP] control, polarisation scrambling, TE-TM mode conversion or separation (G02F1/0353 takes precedence)} - G02F 2202/09: inorganic glass - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS ## Abstract A glass ring for current measurements includes a glass body, which can be disposed around an electrical conductor and has a light entry surface and a light exit surface. The glass ring allows light which enters the glass body through the light entry surface to circulate completely around the conductor in the glass body by reflection on external sides or outer faces of the glass body, the light exiting from the glass body on the light exit surface. The glass ring is formed of a monolithic glass body. A method for optical current measurement includes using a current flow in an electrical conductor to generate an electromagnetic field around the conductor, by which a polarization of a light beam in the glass ring around the conductor, in particular with a plane perpendicular to the longitudinal axis of the conductor, is changed as the light beam circulates around the conductor. ## Claims ### Claim at position 1 1-12. (canceled) ### Claim 13 A glass ring for current measurements, the glass ring comprising: a monolithic glass body configured to be disposed around an electrical conductor, said glass body having a light entry surface, a light exit surface and external sides; said glass body configured to allow light entering said glass body through said light entry surface to completely circulate around the conductor in said glass body due to reflection at said external sides of said the glass body and to allow the light to exit said glass body at said light exit surface. ### Claim 14 (depends on 13) The glass ring according to claim 13, wherein said glass body includes at least one of: two mutually opposite sides each having exactly four corners, or a circular cylindrical through-opening. ### Claim 15 (depends on 14) The glass ring according to claim 14, wherein: said glass body includes first, second, third and fourth sides, and said two mutually opposite sides are fifth and sixth parallel planar sides, or said circular cylindrical through-opening extends through said two mutually opposite sides. ### Claim 16 (depends on 13) The glass ring according to claim 13, wherein said glass body is configured to substantially completely maintain a polarization of the light upon a circulation of light around the conductor without any flow of current. ### Claim 17 (depends on 15) The glass ring according to claim 15, wherein said light entry surface is said third side of said glass body, said third side includes two adjacent partial surfaces being tilted about an angle relative one another, and said third side includes a partial surface. ### Claim 18 (depends on 17) The glass ring according to claim 17, wherein said partial surface has a triangular shape. ### Claim 19 (depends on 17) The glass ring according to claim 17, wherein said glass body includes at least one of: a first planar partial surface of said second side being adjacent to said sixth side, or a trapezoidal partial surface disposed adjacent to said fifth side and formed of two surfaces being tilted relative to one another. ### Claim 20 (depends on 19) The glass ring according to claim 19, wherein: said second side is adjacent to said third side, said first planar partial surface has a trapezoidal shape, said trapezoidal partial surface is formed of two triangular surfaces, and said two surfaces being tilted relative to one another are a second and a third partial surface of said second side. ### Claim 21 (depends on 20) The glass ring according to claim 20, wherein said third partial surface of said second side is tilted about an angle relative to said second partial surface of said second side. ### Claim 22 (depends on 21) The glass ring according to claim 21, wherein said angle about which said third partial surface of said second side is tilted relative to said second partial surface of said second side is 2 degrees. ### Claim 23 (depends on 15) The glass ring according to claim 15, wherein said fourth side is constructed of two mutually adjacent partial surfaces being tilted relative to one another. ### Claim 24 (depends on 23) The glass ring according to claim 23, wherein said fourth side is adjacent to said second side, and each partial surface of said fourth side has a trapezoidal shape. ### Claim 25 (depends on 15) The glass ring according to claim 15, wherein said first side is constructed of two mutually adjacent partial surfaces being tilted relative to one another. ### Claim 26 (depends on 25) The glass ring according to claim 25, wherein said first side is adjacent to said third side, and each partial surface of said first side is trapezoidal. ### Claim 27 (depends on 13) The glass ring according to claim 13, wherein said glass body at least one of: includes a glass having a Verdet constant being greater or smaller than zero, or is formed of a glass having a Verdet constant being greater or smaller than zero. ### Claim 28 (depends on 13) A method for optically measuring currents, the method comprising: providing a glass ring according to claim 13; and using a flow of current in an electrical conductor to generate an electromagnetic field around the conductor, for changing a polarization of a light beam in the glass ring disposed around the conductor during a circulation of the light beam around the conductor. ### Claim 29 (depends on 28) The method according to claim 28, which further comprises orienting the glass ring in a plane perpendicular to a longitudinal axis of the conductor. ### Claim 30 (depends on 28) The method according to claim 28, which further comprises, during the circulation around the conductor, causing the light beam to travel through a monolithic glass body, and changing directions of the light beam by reflection at external sides of the glass body. ### Claim 31 (depends on 30) The method according to claim 30, which further comprises: providing the monolithic glass body with first, second, third and fourth sides; and carrying out the change in directions of the light beam by reflection at least one of: at a third partial surface of the second side being tilted about an angle of 2 degrees relative to a second partial surface of the second side, or at a tilted triangular partial surface of the third side. ### Claim 32 (depends on 31) The method according to claim 31, which further comprises: providing the monolithic glass body with fifth and sixth sides; and causing the light to at least one of: enter the glass body through the light entry surface and exit the glass body through the light exit surface, or enter the glass body through at least one of the third side or two adjacent partial surfaces tilted relative to one another, or exit the glass body through the sixth side. ### Claim 33 (depends on 32) The method according to claim 32, which further comprises causing the light to exit the glass body through the sixth side at an angle of substantially 90 degrees relative to the entering light.