Litton Systems, Inc.

Northrop Grumman Systems Corporation

Northrop Grumman Guidance and Electronics Company, Inc.

Christine E Geosling

Henry C Abbink

Robert E Stewart

Daryl K Sakaida

William P Debley

Gregory A Zimmerman

John P Rahn

Lorrie L Gampp

Charles H Volk

Ralph A Patterson

Youngmin Albert Choi

Robert A Mitchell

Arthur R Martinez

Kenneth W Shafer

Thomas M Flaherty

John M Canfield

James D Assendrup

Ann T Nicol

In one implementation, a chamber is selected that accommodates an array of die structures that comprises one or more cavities. An inner chamber of the chamber is maintained at a first temperature. An alkali metal source of the chamber is maintained at a second temperature greater than the first temperature. An outer chamber of the chamber is maintained at a third temperature greater than the first temperature and the second temperature. The one or more cavities of the array of die structures are filled with a portion of the alkali metal source. The one or more cavities of the array of die structures are sealed to comprise the portion of the alkali metal source.

Middle layer of die structure that comprises a cavity that holds an alkali metal

One or more first portions of a reduced optical material wafer are covered with a masking layer that leaves uncovered one or more second portions of the reduced optical material wafer. The reduced optical material wafer is exposed to an oxidizing atmosphere to reverse a reduction of the one or more second portions of the reduced optical material wafer that makes the one or more second portions receptive for implementation of one or more optical waveguides.

Implementation of one or more optical waveguides in reduced optical material

An apparatus in one example comprises a die structure that comprises a middle layer, a first outside layer, and a second outside layer. The middle layer comprises a cavity that holds an alkali metal, and one of the first outside layer and the second outside layer comprises a channel that leads to the cavity. The middle layer, the first outside layer, and the second outside layer comprise dies from one or more wafer substrates.

An apparatus and method is provided for facilitating ionization of a gas medium of a laser gyroscope. The apparatus and method employ a solid state light emitting device as a start aid for the laser gyroscope. The solid state light emitting device has a wavelength at or below a threshold wavelength based on a work function of a cathode coating material to prompt ionization of a gas medium within the laser gyroscope.

Apparatus and method to facilitate laser gyroscope ionization

One embodiment of the invention relates to a microdevice package containing getters for maintaining a constant vacuum level within the sealed microdevice package. A stacked wafer assembly, containing a plurality of microdevice packages, is formed by aligning a bottom cover wafer with a center wafer. The bottom cover wafer includes one or more bond pads to receive one or more getters. The center wafer includes one or more vias substantially aligned and corresponding to the one or more bond pads. One or more getters are inserted into the one or more vias. The stacked wafer assembly is completed by aligning a top cover wafer opposite the bottom cover wafer to sandwich the center wafer in between. A constant vacuum level is maintained inside the microdevice packages by aligning the wafers, activating the getters, and sealing the microdevice packages in a given sequence.

Method of fabricating a vacuum sealed microdevice package with getters

Vacuum sealed microdevice packaging with getters

An apparatus in one example comprises a wafer portion that comprises a conduction layer. Upon exposure of the conduction layer during a etch of the wafer portion, the conduction layer serves to dissipate a portion of a charge buildup on the wafer portion during an etch of the wafer portion.

Dissipation of a charge buildup on a wafer portion

An integrated optics chip includes an optical waveguide network formed on a surface of an electrooptically active material. The optical waveguide network has an input facet where an optical signal may be input to the optical waveguide network and an output facet where optical signals may be output from the optical waveguide network. One or more trenches is formed in the bottom surface of the surface and arranged to extend into the substrate toward the optical waveguide network to a depth of at least 70% of the thickness. The trenches prevent light rays incident thereon from inside the substrate from propagating to the output facet. In particular, the trenches prevent light scattered at the input facet or from scattering centers in the optical waveguide network from reflecting from the bottom surface of the substrate to the output facet. A cover may be mounted to the top surface of the substrate to provide structural strength to the integrated optics chip. The cover preferably extends substantially the entire length of the substrate. One or more side grooves may be formed in the sides of the substrate and cover. A light absorbing material may be placed in the trenches and grooves. An electrode pattern may be formed on the top surface of the substrate adjacent the optical waveguide network, and a plurality of access electrodes may be formed on sides of the substrate and cover to provide electrical signals to the electrodes.

Multifunction integrated optics chip having improved polarization extinction ratio

An Integrated Optics Chip with improved performance when exposed to rapidly changing temperature is disclosed. The optic chip or integrated optic chip or MIOC has a top surface, a +Z face and -Z face. The chip is formed from a crystal having a high electro-optic coefficient such as Lithium Niobate. For the purpose of orienting the components to the optic chip to be described, the +Z crystal axis extends outward from the +Z face. An input waveguide formed in the top surface of the chip and orthogonal to the +Z axis receives an optical signal from an input port, passes the signal via a waveguide network, to an output waveguide coupling the waveguide network to an output port. Metalization is applied to the top face of the optic chip to form at least a first and a second rail. The first and second rails are positioned to very closely straddle a portion of the input waveguide. A conductive bridge connects the first and second rails to prevent a charge differential from developing between the first and second rails.

Dual purpose input electrode structure for MIOCs (multi-function

An integrated optics chip with improved performance when exposed to changing temperature is disclosed. The optic chip or integrated optics chip or MIOC has a top surface, a +Z face and -Z face. The integrated optics chip is formed from a crystal substrate having a high electro-optic coefficient such as Lithium Niobate. For the purpose of orienting the components to the optic chip to be described, the +Z crystal axis extends outward from the +Z face, the Z axis being the axis across which a pyroelectric effect is exhibited. The top surface is orthogonal to the Z axis. An input waveguide on the top surface receives an optical signal from an input port, passes the signal via a waveguide network, to an output waveguide coupling the waveguide network to an output port. A portion of the +Z and -Z faces are coated at least partially with a conductive coating. A conductive path couples the +Z and -Z faces to prevent a charge differential from developing between the +Z and -Z faces due to a change in temperature of the optic chip and the pyroelectric effect.

Integrated optics chip with reduced thermal errors due to pyroelectric

A method for poling a ferroelectric crystal includes heating the crystal to a temperature above its Curie temperature and applying a first selected voltage to the electrodes to apply an electric field to the crystal. The temperature of the crystal is then reduced to a temperature below the Curie temperature of the crystal, and a second electric field having polarity opposite to the polarity of the first electric field is applied to the crystal. Application of the second electric field reduces nonuniformity in ion concentration across the crystal.

Method for post-poling mobile ion redistribution in lithium niobate

A ring laser gyroscope has an electrically insulating barrier ring placed between the grounded metal mounting device and the frame, which is formed of a lithium aluminosilicate material that contains mobile ions. The barrier ring prevents migration of the ions from the frame material to the mirrors that are used to direct the counterpropagating waves around the closed path in the ring laser gyroscope.

Growing community of inventors

Calabasas, CA, United States of America

Christine E Geosling