Corning Applied Technologies Corporation

Nz Applied Technologies Corp.

Boston Applied Technologies, Incorporated

Run Zhang

Qiushui Chen

Paul Melman

Hua Jiang

Jing Zhao

Gary Y Wang

Kevin Zou

Feiling Wang

Dean Z Tsang

Yingyin Kevin Zou

An electro-optic Q-switch for generating sequence of laser pulses was disclosed. The Q-switch comprises a quadratic electro-optic material and is connected with an electronic unit generating a radio frequency wave with positive and negative pulses alternatively. The Q-switch is controlled by the radio frequency wave in such a way that laser pulse is generated when the radio frequency wave changes its polarity

Electro-optic Q-switch

An optical modulator is provided to control the intensity of a transmitted or reflected light. In a transmission mode, a separator splits arbitrarily polarized light into two polarization rays and one is made to travel a separate path from the other. A recombiner causes the two rays to recombine at an output unless an electro-optic phase retarder changes the polarization of the two rays, in which case, both of them miss the output by an amount which is a function of the voltage on the retarder. A normally-off version with low polarization mode dispersion is obtained by changing the orientation of the recombiner. A normally-on version with low polarization mode dispersion is obtained with a passive polarization direction rotator. Similar results can be obtained in a reflection mode where the input and output are on the same side of the modulator. Versions using a GRIN lens are particularly suited to modulation of light out of and back into fiber-optic cables. The device can be operated as a variable optical attenuator, an optical switch, or a high speed modulator and is insensitive to polarization of the input light. A preferred material for the phase retarder is a hot-pressed ceramic lead lanthanum zirconate titanate composition.

High-speed electro-optic modulator

In a device having a fiber-optic cables, one that is normally an input and one that is normally an out output for light transmission through the device, a first polarization sensitive deflector encompassing the normal input beam and a second polarization sensitive deflector encompassing the normal output beam is followed by a polarization interchanger that interchanges the polarization of beams traveling from the input to the output and leaves unchanged the polarization of beams traveling from the output to the input. This is, in turn, followed by a third polarization sensitive deflector encompassing the input beam and a fourth polarization sensitive deflector encompassing the output beam. Lastly, a lens having a reflector on the side opposite the input and output fibers reflects light beams from the input to the output and conversely. The deflectors encompassing the input beam are arranged to produce a deflection in one direction and the deflectors encompassing the output beam produce a deflection in another direction at least at a 45&deg; angle to the direction of the deflectors encmpassing the input beam. When light travels backwards from the normal output cable to the input cable, the two-dimensional deflections reduce the light that reach the input cable due to imperfections in the optical components, but the deflectors and interchangers are still arranged to maximize the transmission from the normal input to the output cable.

Reflective fiber-optic isolator

Growing community of inventors

Acton, MA, United States of America

Run Zhang