At&t Bell Laboratories

Lucent Technologies Inc.

At+t Corp.

Michele A Milbrodt

Charles H Henry

David Gerald Coult

Henry H Yaffe

Edward J Laskowski

Daryl Inniss

Rudolf F Kazarinov

Raymond A Cirelli

William L Emkey

Renen Adar

Curtis A Jack

Joel C Masland

In accordance with the invention, arrays optical sources are combined in a multilevel planar optical waveguide structure for insertion into an optical fiber laser. The basic element of the combiner is a planar array of multiple waveguides which converge and are gradually tapered to a single output waveguide. A plurality of such elements integrally formed on successive cladding layers provides a high power stack of vertically aligned outputs. An arrangement is described for using such apparatus in the amplification of optical communications signals.

Apparatus for pumping an optical fiber laser

An optical coupler is disclosed which utilizes a pair of polarization selective filters to multiplex a message signal (of perhaps random polarization) with a pair of polarized pump signals onto a common signal path. The filters may be disposed within optical elements (e.g., cubes) which may be physically joined together to form a bulk optic device. An optical isolator may then be directly attached to the output of the bulk polarization independent optical coupler. The positioning of the pump signal inputs with respect to the filters provides either a co-propagating scheme or counter-propagating scheme.

Optical coupler

A waveguide Bragg reflector is made by forming periodic grooves in either the undercladding or the core, applying a high index coating on the grooved surface and selectively removing the coating from the horizontal surfaces while leaving the coating on the vertical surfaces. The waveguide is then completed.

Method for making Bragg reflectors for waveguides

In accordance with the invention the birefringence induced by compressive strain in silica waveguides on silicon substrates is compensated with a high index patch--such as silicon nitride--placed adjacent the core. The patch is disposed sufficiently close to the core to optically couple with the transmitted optical mode. The patch is preferably wider than the core to intersect the exponential tail of the transmitted optical mode. Such a high index patch preferentially couples TE polarization modes. By choosing an appropriate length for the patch, both strain and bend birefringence can be compensated.

Polarization compensated integrated optical filters and multiplexers

In accordance with the invention an integrated optic device useful as a low level polarization independent optical tap comprises a pair of optical waveguides intersecting at an angle of 10.degree.-25.degree. to provide a tap signal in the range minus 20 dB to minus 60 dB. In a preferred embodiment for use in a passive repeater for undersea cable, the device comprises fiber-matching waveguides of phosphorus silicate glass on an oxide covered silicon substrate with a boron and phosphorus silicate cladding. The waveguides preferably intersect at an angle of 13.degree.-16.degree.. The preferred repeater further comprises a 3 dB coupler for averaging the power provided by two external pumping sources and a pair of wavelength division multiplexers for applying the pumping power to the outputs of the tap.

Polarization independent optical tap

An isolated optical coupler arrangement is disclosed which is capable of providing a pump signal and a message signal to a fiber amplifier. The coupler comprises a pair of lenses with a wavelength selective device disposed therebetween. The wavelength selective device is chosen to reflect the pump signal applied as an input to the first lens, and transmit the applied message signal. An optical isolator is inserted in optical path between the wavelength selective device and the second lens to further improve the performance of the coupler.

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Macungie, PA, United States of America

Michele A Milbrodt