Rosemount Inc.

Rosemont Inc.

Other

Roger L Frick

John Paul Schulte

Robert Carl Hedtke

Scott Nelson

Mark Fandrey

Theodore Henry Schnaare

Steven M Behm

Weston R Roper

Adrian C Toy

Richard Louis Nelson

Mark Stephen Schumacher

Brian Lee Westfield

Bennett L Louwagie

Charles Ray Willcox

Kelly Michael Orth

Dale Scott Davis

Thomas A Knecht

Randy Kenneth Paschke

Dean S Pierce

David Andrew Broden

Fred Charles Sittler

Gregory C Brown

Lowell A Kleven

Ahmed H Tewfik

Gerald R Cucci

Stanley E Rud, Jr

Stephen D Anderson

David W Lee

James R Ruesch

Mark A Lutz

Earl A Grindheim

Gregory S Munson

Robert K Snyder

Glen E Monzo

Mark S Shumacher

Steven M Bruesehoff

Steven M Quist

Stanley E Rud Jr

Karen B Carlson

Rafael Jaramillo

Christopher M Throne

An electromagnetic resonant sensor has a dielectric sensor body through which electromagnetic wave energy is propagated. The sensor body has a cavity, with surfaces facing one another to define a gap that varies as a function of a parameter to be measured. The resonant frequency of an electromagnetic standing wave in the body and the variable gap changes as a function of the gap dimension.

Electromagnetic resonant sensor with dielectric body and variable gap cavity

A tunable filter having a resonator with a resonant frequency dependent upon a variable gap is provided. The variable gap may be controllably altered by use of an actuator. The resonator is a high Q resonator that may be formed by a ring resonator, microsphere, microdisc, or other high Q optical structures. Actuation is preferably achieved through an electrostatic actuator that moves a dielectric plate relative to the resonator in response to measured values of gap and temperature.

Tunable optical filter

An optical switch formed of a holographic optical element (HOE) disposed above a top surface of a substrate and moveable relative thereto is shown. Light is traveling through the substrate under total internal reflection, which creates an evanescent field extending beyond the reflecting surfaces of the substrate. The HOE is characterized, in one embodiment, by being formed from a plurality of strips that are moveable between a first position in which the strips are above the evanescent field and a second position in which the strips are inside the evanescent field. In the first position, the light in the substrate propagates unaffected by the HOE in a primary direction of propagation. In the second position, the light in the substrate is altered by the HOE and made to propagate in a reflected direction oblique to that of the primary direction of propagation.

Optical switch with moveable holographic optical element

An optical switch for routing optical signals between optical fibers is shown. Signals are guided internally in an optically transparent substrate by buried waveguides that are directly coupled to the optical fibers. These waveguides form a 3-dimensional optical routing structure internal to the substrate. Signals are coupled between adjacent waveguides by total internal reflection at the surfaces of the substrate. A moveable diffraction grating is coupled to these optical signals at points of total internal reflection via evanescent coupling. This coupling causes a change in direction of the optical signal and routes the signal to the desired waveguide. Known techniques can be used to form the waveguides by writing them with a pulsed laser. Local heating causes a permanent increase in refractive index that forms a single mode waveguide structure. The resulting device has low losses and can be formed by low cost MEMs processes.

Optical switch with 3D waveguides

An optical medium having a cavity that defines a variable gap is provided. The optical medium is used in an optical sensor, laser, and variable frequency resonator, by way of example. The cavity is physically altered in response to changes in a measurable parameter like pressure, temperature, force, flow rate, and material composition. The optical medium is characterized in some embodiments by having a cavity disposed near or within a high Q optical resonator. The optical resonator can be formed by various structures of which Bragg reflector cavities, ring resonators, microdiscs, and microspheres are examples. The optical resonator is preferably coupled to a laser source. The altering of the cavity affects the resonance condition within the optical resonator and thereby the laser signal of the system. If the laser source is a mode locked laser, the repetition rate of the pulse train changes in response to changes in the measurable parameter. If the laser source is a CW source the frequency of the laser signal is dependent upon a measurable parameter.

Optical sensor for measuring physical and material properties

A scalable process transmitter architecture includes a unitized sensor module and an optional scalable transmitter. The sensor module has a sensor output that is configurable which can connect locally to a scalable transmitter module to form a transmitter, or can be wired directly to a remote receiver. The scalable transmitter can mount on the unitized sensor module and generates a scalable output for a remote receiver. The transmitter module can provide more advanced features for specific applications.

Scalable process transmitter

A measurement system includes multiple analog sensor elements and multiple sigma-delta modulators for producing digital outputs. Each sigma-delta modulator receives charge packets from one or more sensor element and charge packets from a shared element (which may be a sensor or a reference element). The sigma-delta modulators are operated synchronously in separate phases, so that the shared element either delivers or does not deliver a charge packet of the sign desired by a sigma-delta modulator only during the phase associated with that sigma-delta modulator.

Multi-phase measurement system with synchronized sigma delta converters

A diffractive optical element (DOE) is shown formed on a substrate. The DOE is characterized, in one embodiment, by being formed from a plurality of members that are each individually created on a top surface of the substrate. The members may be formed by depositing a poly-silicon material on the substrate or by growing a silicon crystal on the substrate and performing an etch step. The substrate may be formed of a sapphire crystal. The DOE may be used to reflect incident light traveling within the substrate under total internal reflection. The widths, spacing between, and heights of the strips forming the DOE may be designed so as to reflect the incident light within the substrate in a direction of propagation acute to that of the incident light.

Integrated transparent substrate and diffractive optical element

A pressure transmitter with a hermetically sealed housing surrounding a cavity that is filled with a gas that is free of integrated circuit contaminants. A sensor circuit including an integrated circuit is placed in the cavity and a gas fill port on the housing is sealed. The sensor circuit is electrically adjustable from outside the pressure transmitter and the integrated circuit is protected from contaminated atmospheres outside the pressure transmitter.

Gas fill system in a pressure transmitter

A pressure sensor integrally formed in the shape of a beam around a central channel. The beam has an integral blind end that is pressurized by the fluid. The beam has an opposite end that is shaped to provide a stepped corner with a gap opening at the base of the stepped corner, where the gap and isolated from the fluid. A sensing film in the channel adjacent the blind end has an electrical parameter that varies with pressure and electrical leads that extend from the channel and out the gap. A seal fills the gap around the leads and the seal fills a portion of the stepped corner. The sensor is preferably formed by direct bonding of single crystal alumina layers. Applications include industrial pressure transmitters, aerospace and turbine engine pressure sensing.

Method and apparatus for a direct bonded isolated pressure sensor

A process sensor module includes a housing with a first fitting that rotatably mates with a corresponding fitting on a bus adapter module. Integrated circuitry in the housing includes a process sensor. A two conductor circuit energizes the integrated circuitry, communicates a sensed process variable to the bus adapter module and communicates data from the bus adapter module to the integrated circuitry. A rotatable coaxial electrical contact is sealed in the first fitting and connects the two conductor circuit to the bus adapter module.

Process sensor module having a single ungrounded input/output conductor

A pressure sensor with a diaphragm that has a dielectric portion that moves in a cavity near capacitor plates that are fixed relative to a mounting frame. The diaphragm is supported on the frame and the frame surrounds the cavity. The diaphragm has an outer surface that receives pressure and has an inner surface facing the cavity. The capacitor plates, which are fixed, sense movement of the nearby dielectric portion and generate an electrical output representative of pressure. Creep of metallizations on a flexible diaphragm are avoided. Manufacture is simplified because metallization of the diaphragm is avoided.

Capacitive pressure sensing with moving dielectric

A pressure sensor module and method for pre-installation without a converter module. The pressure sensor module is hermetically sealed and can remain undamaged in an installation environment without a converter module. The pressure sensor module can be assembled later with a converter module in the installation environment. The pressure sensor module includes an isolator, a pressure sensor and a circuit that provides a bus for energization, control and a digital pressure output. The bus is connected to contacts in an insulating feedthrough. An integrally formed hermetic external support structure surrounds the pressure sensor and circuit. The hermetic external support structure has a threaded process fluid inlet around the isolator, and a threaded support sleeve supporting the feedthrough.

Preinstallation of a pressure sensor module

A pressure transmitter in a process control system for transmitting pressure on a process control loop includes a transmitter housing, an isolation diaphragm configured to couple to a process fluid, and a pressure sensor body of a brittle corrosion resistant material operably coupled to the housing and positioned in the housing. The pressure sensor comprising a first portion bonded to a second portion by a fusion bond, the fusion bond substantially free of foreign material. An isolation fluid is configured to fluidically couple the pressure sensor body to the isolation diaphragm to thereby couple the pressure sensor to a pressure of the process fluid. Measurement circuitry in the transmitter housing coupled to the pressure sensor provides an output which is a function of capacitance, a loop interface in the transmitter housing coupled to the measurement circuitry configured to transmit a pressure related signal on the process control loop as a function of the pressure.

Pressure sensor for a pressure transmitter

Growing community of inventors

Hackensack, MN, United States of America

Roger L Frick