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 optical modulator for application in instrumentation

Abstract: The design and characterization of the first integrated optic modulator for a commercial instrument application are described. Alternative forms of modulation, including direct laser current modulation and optical heterodyne techniques, are reviewed for the application, which requires modulation to 20 GHz. The advantages of an integrated optic modulator fabricated using titanium in-diffused lithium niobate are discussed. Performance tradeoffs between x-cut and z-cut LiNbO/sub 3/ including bandwidth, modulation efficiency, bias point stability, and acoustic resonances are detailed. The x-cut device is found to give the best overall performance for this instrument application. Device reliability and testing, including temperature cycling, humidity, electrostatic discharge, mechanical shock, and vibration are described for complete packaged and pigtailed devices. >

High Performance Mach–Zehnder-Based Silicon Optical Modulators

Abstract: Silicon photonics is poised to revolutionize several data communication applications. The development of high performance optical modulators formed in silicon is essential for the technology to be viable. In this paper, we review our recent work on carrier-depletion silicon Mach-Zehnder-based optical modulators which have formed part of the work within the U.K. Silicon Photonics and HELIOS projects, as well as including some recent new data. A concept for the self-aligned formation of the p-n junction which is flexible in the capability to produce a number of device configurations is presented. This process is the key in having performance repeatability, a high production yield, and large extinction ratios. Experimental results from devices which are formed through such processes are presented with operation up to and beyond 40 Gbit/s. The potential for silicon photonics to fulfill longer haul applications is also explored in the analysis of the chirp produced from these devices and the ability to produce large extinction ratios at high speed. It is shown that the chirp produced with the modulator operated in dual drive configuration is negligible and that an 18-dB dynamic modulation depth is obtainable at a data rate of 10 Gbit/s.

Broad-band guided-wave electrooptic modulators

Abstract: Lumped-element Mach-Zehnder interferometric modulators have been designed, fabricated in LiNbO 3 , tested and analyzed. These modulators had 3 dB bandwidths from 280 MHz to 2.75 GHz and V π 's from 1 V to 4 V, respectively. A simple RLC equivalent circuit is utilized to model the packaged modulator performance and results are compared with those measured using a swept-frequency technique. The model is seen to break down at the higher frequencies due to a frequency-dependent resistance and the electrode and parasitic inductances are seen to limit the overall modulator performance. The effects of varying the electrode capacitance, resistance, or inductance on modulator performance are demonstrated.

Laser printer utilizing a spatial light modulator

Abstract: A laser printer utilizes a total internal reflection spatial light modulator that is optimized to work with a partially coherent laser source. The laser source is a laser diode array having a plurality of multi-mode emitters. The spatial light modulator diffracts light from said laser source according to an applied electric field. A spatial filter having a slit passes designated diffracted light which corresponds to an applied electric field and the light is ultimately imaged onto an image plane by way of an imaging lens.

Low-power thermo-optic silicon modulator for large-scale photonic integrated systems.

Abstract: Silicon platform enables the monolithic realization of large-scale photonic integrated systems. Many emerging applications facilitated by silicon photonics such as optical biosensing, optical neurostimulation, optical phased arrays, holographic displays, 3D cameras, optical machine learning, and optical quantum information processing systems require the integration of a large number of optical phase modulators with modest modulation speed. Classical optical modulators are not suitable for such large-scale integration because of their inability to provide low optical loss, compact size, high efficiency, and wide optical bandwidth, all at the same time. We report a thermo-optic silicon modulator realized in a 0.0023-mm2 silicon footprint of a commercial foundry silicon photonics process. The optical modulator consumes 2.56 mW for 180° phase modulation over 100-nm optical bandwidth while achieving 1.23-dB optical loss without air-gap trench or silicon undercut post-processing. Geometrical design optimization, at the core of this demonstration, is applicable to the realization of compact thermo-optic devices for large-scale programmable photonic integrated systems, with a potential to reduce power consumption roughly by an order of magnitude without sacrificing scalability and optical modulation bandwidth.