# US 12,769,159 B2 · Balun-based differential optical modulator > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,769,159 B2 - Document ID: US12769159B2 - Status: Granted - Kind: B2 - Application number: 19/401,045 - Filed: 2025-11-25 - Published: 2026-05-28 - Granted: 2026-10-20 - Earliest claimed: 2024-11-26 - Assignees: HyperLight Corporation - Applicants: HyperLight Corporation - Inventors: Lingfei Zhao; Jeffrey Cole Holzgrafe; Christian Reimer; Mian Zhang; Sean P. Anderson - Web page: https://patentgrep.com/patent/US12769159B2 ## CPC - G02F 1/0356: {controlled by a high-frequency electromagnetic wave component in an electric waveguide structure} - 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 photonics device is described. The photonics device includes an optical device and a balun. The optical device includes a waveguide and a signal electrode. The waveguide includes a lithium-containing electro-optic material. The signal electrode varies the electric field at the waveguide. The balun is configured to convert a differential input signal to a single-ended output signal. The balun is connected to the signal electrode and provides the signal electrode with the single-ended output signal. ## Claims ### Claim 1 A photonics device, comprising: an optical device including: a waveguide including a lithium-containing electro-optic material; and a signal electrode that varies an electric field at the waveguide; a balun configured to convert a differential input signal to a single-ended output signal, the balun being connected to the signal electrode and providing the signal electrode with the single-ended output signal, the differential input signal including a positive signal and a negative signal, the balun further including: a first input configured to receive the positive signal; a second input configured to receive the negative signal; a first output coupled to the signal electrode and providing the positive signal to the signal electrode; and a second output coupled with a plurality of ground electrodes of the optical device, the second output providing the negative signal to the plurality of ground electrodes. ### Claim 2 (depends on 1) The photonics device of claim 1, wherein the optical device is a traveling wave modulator. ### Claim 3 (depends on 1) The photonics device of claim 1, wherein the first input and the second input are connected to at least one of a digital signal processor and a differential driver. ### Claim 4 (depends on 1) The photonics device of claim 1, wherein the second output divides a current for the negative signal evenly between the plurality of ground electrodes. ### Claim 5 (depends on 1) The photonics device of claim 1, wherein at least one of the first input or the second input is tapered. ### Claim 6 (depends on 1) The photonics device of claim 1, further comprising: a termination network, at least a first portion of the termination network being coupled with a portion of the signal electrode. ### Claim 7 (depends on 6) The photonics device of claim 6, wherein a second portion of the termination network is coupled with the plurality of ground electrodes. ### Claim 8 (depends on 1) The photonics device of claim 1, wherein the balun further comprises: a first ground input; and a second ground input, and wherein the first ground input and the second ground input are coupled with an additional plurality of grounds of the optical device. ### Claim 9 (depends on 8) The photonics device of claim 8, wherein the additional plurality of grounds is coupled with the plurality of ground electrodes. ### Claim 10 (depends on 1) The photonics device of claim 1, wherein a portion of each of the plurality of ground electrodes has a first width, the signal electrode has a second width, and the first width is at least twice the second width. ### Claim 11 (depends on 1) The photonics device of claim 1, wherein the first output and the second output further comprises: a plurality of wire bonds coupling the positive signal to the signal electrode and the negative signal to the plurality of ground electrodes of the optical device. ### Claim 12 (depends on 11) The photonics device of claim 11, wherein a first portion of the plurality of wire bonds couple the positive signal to the signal electrode and a second portion of the plurality of wire bonds couple the negative signal to the plurality of ground electrodes, first wire bonds of the first portion of the plurality of wire bonds being interleaved with second wire bonds of the second portion of the plurality of wire bonds. ### Claim 13 (depends on 1) The photonics device of claim 1, wherein the optical device is in a photonics integrated circuit, at least a portion of the balun being integrated into the photonics integrated circuit. ### Claim 14 (depends on 12) The photonics device of claim 12, wherein the balun is integrated into the photonics device. ### Claim 15 A photonics integrated circuit (PIC), comprising: an optical modulator including: a waveguide including a lithium-containing electro-optic material; and a signal electrode that varies an electric field for the waveguide, the optical modulator being a traveling wave modulator; and a balun having a plurality of inputs and being configured to convert a differential input signal to a single-ended output signal, the balun receiving the differential input signal at the plurality of inputs, being connected to the signal electrode, and providing the signal electrode with the single-ended output signal, the differential input signal including a positive signal and a negative signal, the plurality of inputs receiving the positive signal and the negative signal, the balun further including: a first output coupled to the signal electrode and providing the positive signal to the signal electrode; and a second output coupled with a plurality of ground electrodes of the optical modulator, the second output providing the negative signal to the plurality of ground electrodes. ### Claim 16 (depends on 15) The PIC of claim 15, wherein the optical modulator includes a first region proximate to the balun, a modulation region, and a second region, the modulation region being between the first region and the second region, the second region further comprising: a termination network coupled with the signal electrode. ### Claim 17 A method, comprising: providing an optical device including a waveguide and a signal electrode, the waveguide including a lithium-containing electro-optic material; and providing a balun configured to convert a differential input signal to a single-ended output signal, the balun being connected to the signal electrode and providing the signal electrode with the single-ended output signal, the differential input signal including a positive signal and a negative signal, the balun further including a first input configured to receive the positive signal, a second input configured to receive the negative signal, a first output coupled to the signal electrode and providing the positive signal to the signal electrode, and a second output coupled with a plurality of ground electrodes of the optical device, the second output providing the negative signal to the plurality of ground electrodes, wherein the providing the balun further includes: providing a first metallization layer including the signal electrode, the first input, the second input, and the plurality of ground electrodes; providing a plurality of conductive vias for the signal electrode and the first output; and providing a second metallization layer coupling the first output with the signal electrode through the plurality of conductive vias.