Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.