Optical modulator

About: Optical modulator is a research topic. Over the lifetime, 14068 publications have been published within this topic receiving 196932 citations.

High-Speed, Phase-Dominant Spatial Light Modulation with Silicon-Based Active Resonant Antennas

Abstract: Spatiotemporal control of optical wavefronts is of great importance in numerous free-space optical applications including imaging in 3D and through scattering media, remote sensing, and generation of various beam profiles for microscopy. Progress in these applications is currently limited due to lack of compact and high-speed spatial light modulators. Here we report an active antenna comprising a free-space coupled asymmetric Fabry–Perot resonator that produces a phase-dominant thermo-optic modulation of reflected light at frequencies approaching tens of kilohertz. As a proof of concept for spatial light modulation, we demonstrate a 6 × 6 array of such active antennas with beam deflection capability. The robust design of our silicon-based active antenna will enable large-scale integration of high-speed, phase-dominant spatial light modulators.

Encoding amplitude and phase information onto a binary phase-only spatial light modulator.

Abstract: We report what to our knowledge is a new technique for encoding both amplitude and phase information onto a single binary-valued spatial light modulator. In our approach, we spatially modulate the diffraction efficiency of the filter. Light that is not diffracted into the first order is sent into the zero order, effectively allowing amplitude modulation of either the first-order or zero-order diffracted light. This technique has applications in both optical pattern recognition and image processing. Experimental results are included.

High-speed optoelectronic VLSI switching chip with >4000 optical I/O based on flip-chip bonding of MQW modulators and detectors to silicon CMOS

Abstract: We present the first high-speed optoelectronic very large scale integrated circuit (VLSI) switching chip using III-V optical modulators and detectors flip-chip bonded to silicon CMOS. The circuit, which consists of an array of 16/spl times/1 switching nodes, has 4096 optical detectors and 256 optical modulators and over 140K transistors. All but two of the 4352 multiple-quantum-well diodes generate photocurrent in response to light. Switching nodes have been tested at data rates above 400 Mb/s per channel, the delay variation across the chip is less than /spl plusmn/400 ps, and crosstalk from neighboring nodes is more than 45 dB below the desired signal. This circuit demonstrates the ability of this hybrid device technology to provide large numbers of high-speed optical I/O with complex electrical circuitry.

80-GHz Bandwidth and 1.5-V V π InP-Based IQ Modulator

Abstract: We report a promising IQ optical modulator for beyond 100-GBd transmitter. By introducing both a new n-i-p-n heterostructure and an optimized capacitance-loaded traveling-wave electrode (CL-TWE), high-frequency electrical losses of the modulator can be drastically reduced. As a result, we extended an electro-optic (EO) bandwidth without degrading other properties, such as half-wave voltage (Vπ) and optical losses. The 3-dB EO bandwidth of the 1.5-V Vπ modulator reaches 80 GHz. Furthermore, we demonstrated up to 128-GBd IQ modulations by co-assembling with an ultra-broadband InP-based driver IC.

Liquid crystal optical modulator

Abstract: A liquid crystal optical modulator having a liquid crystal held between two substrates each having a light-transmissive electrode on the surface, in which at least one substrate has minute alignment-treated region having two or more kinds of liquid crystal aligning abilities different from each other formed and arranged on the same substrate.