Abstract:
PROBLEM TO BE SOLVED: To attain velocity matching and a small propagation loss with small electrode film thickness and to simultaneously reduce Vπ/L, the ratio of a drive voltage Vπ to the length of the electrode L, in the optical modulation electrode of an optical modulator. SOLUTION: A substrate main body 2 is composed of an electro-optic material and is equipped with one principal surface 2a and the other principal surface 2b facing each other. An optical modulation electrode 20A for applying voltage for modulating light propagating through optical waveguides 6A, 6B is disposed on the substrate main body 2. The electrode 20A includes earth electrodes 3A, 3B and a signal electrode 4. The ratio of the width W of the signal electrode 4 to the gap G between the earth electrodes 3A, 3B and the signal electrode 4, W/G, is 0.8 or more. Preferably, the thickness T of the substrate main body 4 is 20 μm or less in a region where the optical waveguides 6A, 6B are formed. COPYRIGHT: (C)2004,JPO&NCIPI
Abstract:
A distributed traveling-wave Mach-Zehnder modulator driver having a plurality of modulation stages that operate cooperatively (in-phase) to provide a signal suitable for use in a 100 Gb/s optical fiber transmitter at power levels that are compatible with conventional semiconductor devices and conventional semiconductor processing is described.
Abstract:
An optical module that processes an input optical signal and outputs a processed optical signal is disclosed. The optical module provides a housing and an optical processing device in the housing. The housing provides an optical input port and an optical output port in a first wall thereof in side-by-side arrangement. A third wall of the housing only provides RF terminals. Second and fourth walls of the housing provide DC terminals. Electrical connection between the DC terminals with DC pads on the device is realized through a wiring substrate whose top avoids an optical path from the optical input port to the input port of the device.
Abstract:
A Mach-Zehnder optica! modulator with a series push-pull traveling wave electrode uses a balanced coplanar stripline with lateral ground planes (G1,G2). Two signal electrodes (13A,13B) extend along the center of the optical modulator adjacent and parallel to the optical waveguides (15A,15B) in a series push-pull configuration. The ground planes (G1, G2) run parallel to the signal electrodes (13A,13B), but are spaced laterally outward from the signal electrodes (13A,13B).
Abstract:
A transmission line (304) includes a plurality of segments forming an electrical path (203) and a continuous optical waveguide (205) passing through the segments. Discrete inductors (102) are formed between and connect adjacent segments. The inductors (102) are formed in a plurality of metal layers of an integrated circuit so as to balance the capacitance of an optical modulator which includes the transmission line (304) formed on the optical waveguide (205), thereby achieving a predetermined characteristic impedance for the transmission line. A delay locked loop (305) is used to control varactors (302) so as to match the delays of the optical and electrical signals. Optical waveguide segments (210) may be used to match the delays.