G02F2201/126

Electro-optic modulation structures
10247999 · 2019-04-02 · ·

An electro-optic modulation structure comprises a first electrode and a second electrode and a first electro-optic strip; wherein the first electrode has a slab portion and a first ridge protruding from the slab portion of the first electrode, and the second electrode has a slab portion and a first ridge protruding from the slab portion of the second electrode, the first protruding ridge of the first electrode and the first protruding ridge of the second electrode being disposed on opposite sides of the first electro-optic strip and both protruding ridges abut the first electro-optic strip.

Waveguide modulator structures

An optoelectronic device and method of making the same. In some embodiments, the optoelectronic device includes a substrate, a Mach-Zehnder waveguide modulator, and an epitaxial crystalline cladding layer. The Mach-Zehnder waveguide modulator includes a left arm including a left SiGe optical waveguide, and a right arm including a right SiGe optical waveguide, each of the left and right optical waveguides including a junction region and a plurality of electrodes for providing a bias across the junction to enable control of the phase of light travelling through the junction regions via dispersion. The epitaxial crystalline cladding layer is on top of the substrate and beneath the junction region of the left optical waveguide and/or the junction region of the right optical waveguide, and has a refractive index which is less than a refractive index of the respective junction region(s), such that optical power is confined to the respective junction region(s).

Optical modulator with improved efficiency

An optical modulator circuit includes first and second electrodes, first and second p-n junction segments (PNJSs), and first and second optical waveguides. The first PNJS includes a first modulating p-n junction (MPNJ) in series with a first non-modulating device (NMD) that are connected to the first and second electrodes, respectively, where the first NMD includes a first substantially larger capacitance than the first MPNJ. The second PNJS includes a second NMD in series with a second MPNJ that are connected to the first and second electrodes, respectively, where the second NMD includes a second substantially larger capacitance than the second MPNJ. The first and second optical waveguides superimpose the first and second MPNJs, respectively, where the first and second MPNJs are configured to modulate a refractive index of the first and second optical waveguides, respectively, based on the substantially larger capacitance of the first NMD and the second NMD.

Balanced Mach-Zehnder modulator
10120259 · 2018-11-06 · ·

An apparatus for modulating a beam of light with balanced push-pull mechanism. The apparatus includes a first waveguide comprising a first PN junction on a substrate and a second waveguide comprising a second PN junction on the silicon-on-insulator substrate. The second PN junction is a replica of the first PN junction shifted with a distance. The apparatus further includes a first source electrode and a first ground electrode coupled respectively with the first PN junction and a second source electrode and a second ground electrode coupled respectively with the second PN junction. The apparatus additionally includes a third ground electrode disposed near the second PN junction at the distance away from the second ground electrode, wherein the first ground electrode, the second ground electrode, and the third ground electrode are commonly grounded to have both PN junctions subjected to a substantially same electric field varied in ground-source-ground pattern.

OPTICAL MODULATOR DRIVERS
20180314080 · 2018-11-01 ·

One example of a system includes an optical modulator, a push-pull driver, and a compensation circuit. The optical modulator has a nonlinear capacitance. The push-pull driver is electrically coupled across the optical modulator. The push-pull driver charges the capacitance in response to a logic 1 of a level-shifted differential signal and discharges the capacitance in response to a logic 0 of the level-shifted differential signal. The compensation circuit increases the speed of the discharge of the capacitance in response to the level-shifted differential signal transitioning from a logic 1 to a logic 0.

OPTICAL MODULATOR WITH IMPROVED EFFICIENCY
20180307062 · 2018-10-25 ·

An optical modulator circuit includes first and second electrodes, first and second p-n junction segments (PNJSs), and first and second optical waveguides. The first PNJS includes a first modulating p-n junction (MPNJ) in series with a first non-modulating device (NMD) that are connected to the first and second electrodes, respectively, where the first NMD includes a first substantially larger capacitance than the first MPNJ. The second PNJS includes a second NMD in series with a second MPNJ that are connected to the first and second electrodes, respectively, where the second NMD includes a second substantially larger capacitance than the second MPNJ. The first and second optical waveguides superimpose the first and second MPNJs, respectively, where the first and second MPNJs are configured to modulate a refractive index of the first and second optical waveguides, respectively, based on the substantially larger capacitance of the first NMD and the second NMD.

Enhanced push-pull (EPP) waveforms for achieving primary color sets in multi-color electrophoretic displays
12087244 · 2024-09-10 · ·

Enhanced push pull driving waveforms for driving a four particle electrophoretic medium including four different types of particles, for example a set of scattering particles and three sets of subtractive particles. Methods for identifying a preferred waveform for a target color state when using a voltage driver having at least five different voltage levels.

WAVEGUIDE MODULATOR STRUCTURES

An optoelectronic device and method of making the same. In some embodiments, the optoelectronic device includes a substrate, a Mach-Zehnder waveguide modulator, and an epitaxial crystalline cladding layer. The Mach-Zehnder waveguide modulator includes a left arm including a left SiGe optical waveguide, and a right arm including a right SiGe optical waveguide, each of the left and right optical waveguides including a junction region and a plurality of electrodes for providing a bias across the junction to enable control of the phase of light travelling through the junction regions via dispersion. The epitaxial crystalline cladding layer is on top of the substrate and beneath the junction region of the left optical waveguide and/or the junction region of the right optical waveguide, and has a refractive index which is less than a refractive index of the respective junction region(s), such that optical power is confined to the respective junction region(s).

Dual-ring-modulated laser that uses push-pull modulation

A dual-ring-modulated laser includes a gain medium having a reflective end coupled to a gain-medium reflector and an output end coupled to a reflector circuit to form a lasing cavity. This reflector circuit comprises: a first ring modulator; a second ring modulator; and a shared waveguide that optically couples the first and second ring modulators. The first and second ring modulators have resonance peaks, which are tuned to have an alignment separation from each other. During operation, the first and second ring modulators are driven in opposing directions based on the same electrical input signal, so the resonance peaks of the first and second ring modulators shift wavelengths in the opposing directions during modulation. The modulation shift for each of the resonance peaks equals the alignment separation, so the resonance peaks interchange positions during modulation to cancel out reflectivity changes in the lasing cavity caused by the modulation.

Modulator Arrangements
20240385490 · 2024-11-21 ·

The disclosure relates to a modulator arrangement, including an optical thin film lithium niobate Mach-Zehnder modulator with a first and a second waveguide arm arranged on a substrate. The first and the second waveguide arm each include an area formed of lithium niobate; an electrode arrangement for generating an electric field which at least sectionally acts on the first and the second waveguide arm. The electrode arrangement includes a first and a second signal line as well as a first and a second ground line. The first signal line at least sectionally extends above the first waveguide arm so that the first signal lineas seen in a direction perpendicular to the substrateis aligned with the first waveguide arm. The second ground line at least sectionally extends above the second waveguide arm so that the second ground lineas seen in a direction perpendicular to the substrateis aligned with the second waveguide arm; and a differential driver for providing a voltage for the Mach-Zehnder modulator. A signal output of the driver is connected to the first signal line and a ground output is connected to the second ground line.