Lucent Technologies Inc.

Agere Systems Guardian Corp.

Chellappan Narayanan

Herman M Presby

Benjamin Irvin Greene

Scott Thomas Davies

Yuan P Li

Francis McCarthy Mess

Robert M Atkins

Giovanni Barbarossa

Daren Li

Jianluo Zhang

Kevin G Sullivan

Transmission characteristics of an optical device , fabricated from multiple layers of silica-based glass on a silicon substrate , are modified by localized thermal treatment. The beam of a carbon-dioxide (CO ) laser is used to selectively soften the core and/or cladding material of a waveguide structure during or after the fabrication process. In one application, softening relieves the strain developed between the waveguide structure and the silicon substrate and substantially reduces or eliminates birefringence. In a second application, the CO laser is operated at another power level in order to modify the index of refraction. Changes in the index of refraction change the speed of light through a waveguide thereby changing the phase shift associated with the waveguide. In a third application, the CO laser is operated at yet another power level to increase the transmission loss of the waveguide. In all of the embodiments, heat treatment is substantially faster and/or less expensive than known techniques for modifying the transmission characteristics of an optical device.

Optical device having modified transmission characteristics by localized thermal treatment

A method for preparing operative end faces of integrated circuit chips or dies utilizes a beveled cutting blade to impart a desired contact angle to the operative end faces of the chip. The method includes the steps of mounting feet on the chip, trimming the feet where necessary, mounting the chip on a fixture with tape, cutting the end faces, and removing the chip from the fixture.

Method of preparing end faces on integrated circuits

Disclosed is an apparatus for testing an array of optical fibers. According to the invention, modulated light is projected through individual fibers of a fiber array onto a photo-sensitive position sensor. The photo-sensitive sensor will provide position information relative to the position of the light projected upon its surface to a system computer. The positions of the optical fibers within the array relative to each other may thus be found. A loop is introduced into the optical fibers to lower the wavelength at which the fiber is multi-moded. The actual positions of the optical fibers are compared to desired positions and the fiber array is accepted or rejected based on whether it meets predetermined limits.

Fiber array test method and apparatus

An optical interconnection device has a passive control mechanism for substantially eliminating thermal effects on optical properties of the apparatus Specifically, the interconnection apparatus includes a control material coupled to an optical circuit substrate, wherein the control material has a thermal expansion coefficient that is different than a substrate thermal expansion coefficient. In response to an increase or decrease an ambient temperature, the control material thermally expands or contracts at a different rate than the substrate to create a non-planar substrate distortion transmitted to the core portion, thereby creating a temperature independent optical path length within the optical core portion.

Optical device having a temperature independent spectral response using

An optical planar waveguide notch filter employs a waveguide with first, second and third regions. The first and third regions have structures for propagating an optical signal in a first transmission mode. The second region is located between the first and third regions and has a structure in which an optical signal propagates in the first transmission mode as well as at least one other higher order transmission mode. The structure of the second region further couples a particular wavelength band of the signal propagating in the first transmission mode to at least one of the other transmission modes. This coupling causes an attenuation of energy of such bandwidth in the signal propagating in the first transmission mode. As a result, the signal propagating from the second region to the third region in the first transmission mode is a notch filtered signal possessing an attenuation at the particular wavelength band.

Optical planar waveguide notch filters

In many assembly applications of optical arrays, a bridging member is bonded to the arrays to hold them securely. It has been found that a pad made of layers of glass and silicon provides an efficient heat transmitting structure for this purpose. Because glass is absorbent to laser radiation at 10.6 .mu.m, it absorbs all the incident laser radiation, and imparts the heat generated to the silicon, which transmits it uniformly over its entire surface. The heat can then be used to melt solder or to heat-cure an adhesive, thereby affecting a robust mechanical bond in an efficient and rapid manner.

Multilayered connector pads for supporting butt-joined optical arrays

A method is provided of trimming the optical coupling ratio of an optical coupler to a prescribed value. The optical coupler is formed from a plurality of waveguides which each include a core and cladding. In accordance with the method, an irradiation energy is selected that is absorbed by portions of the waveguides located in a coupling region. A dosage of radiation is applied to the waveguide portions at least sufficient to adjust the optical coupling ratio to the prescribed value. The radiation, which may be absorbed by the cladding and/or the core of the waveguides, causes a change in the refractive index difference between the core and cladding of the waveguides. This change in the refractive index difference will result in a change in the optical coupling ratio of the device.

Radiolytic method for trimming planar waveguide couplers

A method of making a silicate optical waveguide structure for transforming an optical beam of a first modal spot size to a beam of a second modal spot size includes the step of selecting an irradiation energy which is at least partially absorbed by the cladding of the structure. A variable dosage of radiation is then provided along the length of the structure. The radiation has an energy equal to the selected irradiation energy so that a refractive index change of the cladding is greater than a refractive index change of the core.

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Alpharetta, GA, United States of America

Chellappan Narayanan