Embodiments of the present disclosure provide devices and methods involving the thermal stabilization of microring resonators, such as microring modulators. Power is measured via an on-chip photodetector integrated with a drop port of the microring resonator, providing a local measurement of average power. This average power is employed as a feedback measure to actively control a heater that is integrated with the microring resonator, in order to stabilize the resonant wavelength of the microring resonator in the presence of thermal fluctuations. Employing such a system, a microring modulator can maintain error-free performance under thermal fluctuations that would normally render it inoperable.

An electro-optic modulator of a test and measurement system. The electro-optic modulator includes a first electrode, a second electrode with identical electrical characteristics as the first electrode and an optical waveguide between the first electrode and the second electrode. The first electrode and the second electrode present a balanced load to a device under test.

A method for operating an optical system may include selecting a band gap energy level for an optical waveguide in an electro-optic modulator. The band gap energy level may correspond to a predetermined phase shift efficiency of a waveguide electrode coupled to the optical waveguide. The method may further include generating, across a conductive plane in the electro-optic modulator, a differential voltage that produces a predetermined temperature in a waveguide core of the optical waveguide. The predetermined temperature may correspond to the band gap energy level selected for the optical waveguide. The method may further include transmitting, through the optical waveguide and with a modulating voltage applied by the waveguide electrode, an optical wave to an optical wave combiner. The modulating voltage may produce an amount of phase shift in the optical wave at the predetermined phase shift efficiency.

The present invention describes a semiconductor interferometric device capable of modulating an electromagnetic wave by modulating the carrier concentration inside a semiconductor device. The variation of the carrier concentration within the device causes the variation of the physical properties inside the semiconductor material leading to a shift of the reflected and absorbed spectrums. One or more rays are generated within the device so as to operate the device through interference effects. The present invention may be utilized for an antenna or for beam steering purposes comprising an array of semiconductor interferometric reflecting devices. Furthermore the same principle could be utilized to generate tunable meta-surfaces, so as to modulate phase, amplitude or polarization of an incident electromagnetic wave.

A window control system is provided that includes a plurality of electro-optic windows each having a variable transmittance level, a portable control unit for generating wireless control signals for controlling the transmittance level of the electro-optic windows, and a plurality of window control circuits each coupled to a respective one of the electro-optic windows and each having a transceiver for receiving the wireless control signals from the portable control unit. Each window control circuit is configured to adjust the transmittance level of the respective one of the electro-optic windows in response to a wireless control signal received by the transceiver from the portable control unit.

The objective of the present invention is to provide an optical modulator adapted for use with various modulating units and various modulation regions, and with which variability in optical losses is limited as far as possible. An optical modulator in which an optical waveguide and a control electrode for controlling an optical wave propagating through the optical waveguide are provided in a substrate, characterized in that: the optical waveguide is provided with a first branching portion which causes one input light beam to branch into two light beams; each of a first and a second modulating portion connected to two branched waveguides which branch at the first branching portion is provided with a structure in which one or more Mach-Zehnder type optical waveguides are combined; the control electrode comprises signal electrodes which apply modulated signals to the first and second modulating portions; input portions of all the signal electrodes are disposed on either the left or the right of the substrate relative to the direction in which the optical wave propagates; and in relation to output portions of the signal electrodes, the output portions of the signal electrodes led out from each modulating portion are disposed on the side on which the first or second modulating portions are disposed, relative to the direction in which the optical wave propagates.

An electrochromic device includes a nanostructured transition metal oxide bronze layer that includes one or more transition metal oxide and one or more dopant. The electrochromic device also includes nanoparticles containing one or more transparent conducting oxide (TCO), a solid state electrolyte, a counter electrode, and at least one protective layer to prevent degradation of the one or more nanostructured transition metal oxide bronze. The nanostructured transition metal oxide bronze selectively modulates transmittance of near-infrared (NIR) and visible radiation as a function of an applied voltage to the device.

An optical transmission device includes an optical modulator and a processor. The optical modulator optically modulates an optical signal with a driving signal to output a modulated optical signal. The processor performs ABC on a bias of the optical modulator, using the modulated optical signal, so as to cause the bias to converge to an optimum point. The processor starts the ABC using a modulated optical signal optically modulated with a QPSK signal at start-up timing, acquires an optimum value that is a bias value when the bias converges to the optimum point, and stops the ABC. After the ABC is stopped, the processor sets the acquired optimum value as an initial value, and restarts the ABC using a modulated optical signal optically modulated with an N-QPSK signal.

A digital optical transmitter of the present invention comprises an optical modulator, pre-equalization factor computation means for generating transform functions for compensating waveform distortion to occur in the optical modulator, and pre-equalization signal generation means for outputting third data and fourth data after creating them by performing a pre-equalization process on first data and second data. Here, through the transform functions, the first data is added to the fourth data, in a manner depending on a characteristic of the optical modulator, and the second data is added to the third data, in a manner depending on a characteristic of the optical modulator.

A driving circuit for a display panel is provided as well as a display apparatus. The driving circuit includes a plurality of timing controllers, a plurality of source drivers and a gamma voltage generation circuit. The gamma voltage generation circuit is used to supply a plurality of gamma voltages to each of the plurality of source drivers. The display apparatus includes the driving circuit.