Industrial Technology Research Institute

Chen-Bin Huang

Chieh Hu

Wei-Jen Chou

Chih-Tsung Shih

Ming-Hung Chen

Yu-Chen Yu

Shu-Mei Yang

Lih-Gen Sheu

Chin-Lan Liao

Daniel Yen Chu

Eric Gung-Hwa Lean

This specification discloses a power polarization beam combiner and its applications in fiber communications. The power polarization beam combiner uses the photonic band gap formed in a photonic crystal to produce a left-hand material with a negative refractive index and high dispersion rate. Using such properties of the photonic crystal, several beams with different wavelengths and polarizations are combined and output to a common port.

Power polarization beam combiner and its applications in fiber communication

A three-port optical polarization combiner is disclosed. It is used for combining two optical pump beams to increase optical pumping power in a DWDM optic fiber transmission system. The combiner will combine two beams with orthogonal polarizations into one and transmit it to another port for output. By non-reciprocal effect of a half-wave plate and a Faraday rotator, the reverse noise will be blocked to improve transmission quality and protect the laser lens.

Three-port optical polarization combiner

This specification discloses a light signal interleaver, which can separate a light signal into two light signals with a large interval in between. A birefringent plate is used as a light signal interleaver to separate all wavelengths in a light signal into an O-ray and an E-ray. Therefore, the invention can increase the total transmission capacity under the existent network structure.

Optical signal interleaver

This specification discloses a reflective optical circulator, which uses an optical reflective device to reflect an incident light beam from an optical port so that the reflected light beams further pass through all optical devices (i.e., all sorts of optical crystals) on the optical paths. With a proper reciprocal-non-reciprocal optical crystal combination, a particular linear polarization direction is generated to guide the reflected beams to the next optical port. The invention achieves the effect of repeatedly using crystals, lowering the number of crystals and the length of the optical circulator. On the other hand, all optical ports can be installed on the same side of the optical circulator, minimizing the device and making it easy to use.

Reflective optical circulator

The invention provides a compact optical circulator with three ports positioning between a dual-core collimator and a single-core collimator. The inventive circulator has a propagation director to couple a light from the dual-core collimator to one port of the circulator and another light form the other port of the circulator to the dual-core collimator. The invention further provides a compact optical circulator with three ports having a reflective compensator. The reflective compensator compensates the optical path length of two polarized beams. Furthermore, the invention eliminates the polarization mode dispersion by utilizing a reflective compensator. As well, the inventive circulator forgoes use of the reciprocal polarizing-rotating unit, thus reducing production costs.

Compact optical circulator with three ports

The invention provides an optical circulator that comprises three ports with the property that light entered through the nth port is output through the (n&plus;1)th port. It can be applied to optical fiber transmission of optical signals. It uses a reflector to make a two-core fiber collimator to be a first port and a second port of the optical circulator so as to minimize the optical circulator volume and to simplify the assembly procedure. A reciprocal crystal and a non-reciprocal crystal are combined to form an optical polarization controller to conquer such technical problems as the conjugate angle of the two-core collimator and the minimal polarization mode dispersion. In particular, the corresponding relation between the Faraday rotator and the birefringent crystal optical axis can be utilized to remove half-wave plates used in ordinary optical circulators, thus lowering manufacturing costs and complexities.

Optical circulator

The present invention pertains to a polarization independent tunable acousto-optical filter and the corresponding method. The filter diffracts an input light beam into a first input light beam unaffected by acoustic waves and a second input light beam affected by acoustic waves. A polarization beam displacer/combiner is employed to separate the input light beam into two orthogonal beams. Several polarized rotators are used to rotate the polarization of light by 90 degrees. An acousto-optical device makes the polarization of light with a particular wavelength rotate by 90 degrees. The two beams are then properly combined to form orthogonal beams. The filtering method has nothing to do with the polarization of the incident light. The filter has such advantages as a high extinction ratio, a small volume and a lower cost.

Growing community of inventors

Hsinchu, Taiwan

Chen-Bin Huang