Oplink Communications, Inc.

Yanfeng Yang

Feng Quan Liu

Wei-Zhong Li

Wei Luo

Shijie Gu

Zhanxiang Zhang

Wei Zhong Li

The present invention provides an optical dispersion compensator with relatively small size and low insertion loss comprising a Fabry-Perot etalon and a dual-fiber collimator having a dual-fiber pigtail and a GRIN lens. The dual-fiber pigtail has an input fiber and an output fiber. An optical signal is coupled into the input fiber and then collimated by the GRIN lens into a collimated incident beam that is incident on the Fabry-Perot etalon with an incident angle. The collimated incident beam is reflected back by the Fabry-Perot etalon into a collimated reflected beam that is collected by the GRIN lens and coupled into the output fiber. By adjusting the separation between the input fiber and the output fiber of the dual-fiber pigtail, the collimated incident beam will change its incident angle and reflected angle. By tuning this angle, the group delay pattern of the output optical signal through the output fiber will shift along with wavelength, therefore dispersion compensation can be achieved. The insertion loss of the optical dispersion compensator is as low as 0.25 dB. It is also possible to cascade two or more optical dispersion compensators together to form an optical dispersion compensation system.

Miniature optical dispersion compensator with low insertion loss

A polarization splitter and combiner for processing a beam containing a first polarization and a second polarization to spatially separate these polarizations by using a birefringent element for receiving the beam and walking off the first polarization from the second polarization by an initial walk-off distance. A first lensing element with an optical axis is oriented to admit the first polarization at a first input point and output the first polarization at a first output angle to the optical axis and the second polarization at a second output angle to the optical axis. A second lensing element positioned after the first lensing element is oriented to receive the polarizations at input angles equal to their respective output angles, and outputs both polarizations at a first and second output point respectively. In a symmetrical arrangement, the first and second output points are separated by the initial walk-off distance. Additional walk-off control elements and optics can be interposed between the first and second lensing elements, depending on the functionality of the beam splitter and combiner or optical device employing the same.

Polarization splitter and combiner and optical devices using the same

A method and system for providing a splitter/combiner is disclosed. The splitter/combiner includes a first birefringent wedge having a first optic axis and a first wedge angle and a second birefringent wedge having a second optic axis and a second wedge angle. The second birefringent wedge is optically coupled with the first birefringent wedge. The second wedge angle is complementary to the first wedge angle. The second optic axis is perpendicular to the first optic axis such that an extraordinary signal for the first birefringent wedge is an ordinary signal for the second birefringent wedge. The first and second birefringent wedges establish a first path for a first portion of a first optical signal and establish a second path for a second portion of the first optical signal. The first path and the second path are separated by an angle. The first optical signal travels from the first birefringent wedge to the second birefringent wedge. The first birefringent wedge and the second birefringent wedge also combine a second optical signal travelling along the first path with a third optical signal travelling along the second path. The second optical signal and the third optical signal travel from the second birefringent wedge to the first birefringent wedge.

Growing community of inventors

Sunnyvale, CA, United States of America

Yanfeng Yang