Abstract: A micromachined stepper motor having a toothed slider connected at either end to spring flexures. At least one of the spring flexures is positioned between a load, such as a high pass optical filter, and the slider. The slider is positioned within three stators that are sequentially energized such that they move the slider along its longitudinal axis. The springs and guide posts hold the slider in place and establish a rest position when no driving force is applied.

Abstract: A tool, and the method of making the tool, for process system identification that is based on the general purpose learning capabilities of neural networks. The tool and method can be used for a wide variety of system identification problems with little or no analytic effort. A neural network is trained using a process model to approximate a function which relates process input and output data to process parameter values. Once trained, the network can be used as a system identification tool. In principle, this approach can be used for linear or nonlinear processes, for open or closed loop identification, and for identifying any or all process parameters.

Abstract: A rugged ultrasonic sensor is provided which is capable of detecting objects in very close proximity to the sensor. This close proximity detection includes the detection of objects which are immediately adjacent the sensor housing. Such close range operation is achieved by tailoring the transducer to operate at previously undesirable conditions, including low Q and high frequency. Such operating conditions allow the resonating characteristics of the transducer not to interfere with close range operation.

Abstract: An efficient method brings together two wafers of dies that contain an infrared transparent window or top cap with either an infrared detector or emitter array to produce a low cost infrared package. A low thermal conductivity gas or a vacuum may be used between the wafers for enhanced thermal isolation. Joining of the wafers is preferably by solder, although ultrasonic bonding can be used.

Abstract: A method of driving and sensing a resonant sensor network wherein a least a one resonant sensor is driven by a first light from a first light source at a first frequency, wherein said first light source is modulated by an a.c. source. A second light source at a second frequency is utilized sense the resonant frequency of the at least one resonant sensor. Wherein said at least one resonant sensor modulates said second light source. The modulated light is provided to a photo detector and the first light source is filtered out of said reflected light. The detector ac amplifies the filtered reflected light, thereby detecting said the resonant frequency of the resonant sensor.

Abstract: A Vertical-Cavity Surface Emitting Laser (VCSEL) for producing a filamented light output. In a preferred embodiment, this is accomplish by providing a number of discrete objects that are positioned adjacent to or within one or both of the cladding mirrors, or within the active region itself. The discrete objects may alter the reflectance, current injection and/or gain of the VCSEL at corresponding discrete locations, thereby causing the filamented light output. Besides providing a filamented output, the VCSEL of the present invention operates at a low drive current, provides high performance, and occupies less physical area than a broad-area (wide aperture) VCSEL. Thus, the VCSEL of the present invention has a number of advantages provided by a conventional laser including speed, efficiency and power, but does not suffer from many of the disadvantages of high coherence. The utilization of speckle averaging within multi-mode fiber interconnections and CD-like spatial imaging applications are contemplated.

Abstract: A low-cost, accurate enthalpy sensor is described. The invention provides an on/off output which reflects the result of a comparison between the enthalpy level of a space and a predetermined setpoint. The sensor combines a signal representative of humidity with a signal representative of temperature to create a signal representative of enthalpy. The signal representative of enthalpy is compared with a predetermined setpoint to determine if the enthalpy level is above or below the setpoint. An output is then produced which indicates whether the output representative of enthalpy is above or below the predetermined setpoint.

Abstract: A resistance to frequency circuit for measuring the ambient temperature on a thermostat. The temperature measuring circuit comprises a first Schmitt trigger NAND gate, a rectifier, a capacitor of which one terminal is electrically connected to ground, a first resistor, a thermistor and possibly a second resistor. The capacitor is connected with the cathode electrically connected to ground, the anode is electrically connected to the first input of a NAND gate. The output of the NAND gate is electrically connected to the anode of the rectifier. The cathode of the rectifier is electrically connected to both the thermistor and the first resistor. The second terminal of the first resistor is electrically connected to the anode of the capacitor and the first input to the NAND gate. The thermistor is electrically connected to a tri-state buffer of the microprocessor. The circuit uses the open drain output ports of a microprocessor to provide the multiplexer function of the A/D.

Abstract: The method of making the tool, for process system identification that is based on the general purpose learning capabilities of neural networks. The method can be used for a wide variety of system identification problems with little or no analytic effort. A neural network is trained using a process model to approximate a function which relates process input and output data to process parameter values. Once trained, the network can be used as a system identification tool. In principle, this approach can be used for linear or nonlinear processes, for open or closed loop identification, and for identifying any or all process parameters.

Abstract: A form pressure sensor diaphragm and method of making that allows for formation of long rectangular plate structures in semiconducting materials, especially silicon. A plurality or multiplicity of sensors may be constructed on a single chip, thus providing for absolute and relative sensing of pressure on a single device.

Abstract: A method of calibrating a dimmable lighting system having an electric lighting fixture and light sensor in an electronic controller. The method comprises a system which makes eight measurements while controlling illumination levels from both indoor and outdoor lighting. The method calculates a set point and a gain which are utilized to maintain a constant lighting level at a lighting point of interest.

Abstract: This patent relates to the fabrication of diaphragm-based microstructures used primarily for sensing physical phenomena by detecting a change in deflection, resonance, or curvature of the diaphragm. The methods of fabrication described and claimed herein relate primarily to diaphragm-based diaphragms made of silicon, either single crystal or polycrystalline in form, although other materials may be used.

Abstract: A controller for a climate control system has a relative humidity sensor as well as a dry-bulb temperature sensor within the enclosure. The humidity value is used in conjunction with the dry-bulb temperature to generate an enthalpy error signal which is a function of both the dry-bulb temperature and the relative humidity values. This permits robust control of both enclosure temperature and enclosure humidity without abnormal cycling of the climate control system. Instead of using a sensor which directly measures the enthalpy, the enthalpy can be synthesized from the relative humidity and dry-bulb temperature within the enclosure. Alternately, the sensed and set point enthalpy values can be synthesized from any two thermodynamic properties of the moist air within the enclosure.

Abstract: An apparatus for replicating diffractive optical elements by embossing a master optical element into a photopolymer material disposed on a substrate, including a fixture for retaining, aligning, and conveying radiation to the embossing sample so that the photopolymer cures under pressure. Intermediate nickel optical elements may be used in lieu of quartz optical masters. The liquid processing techniques disclosed herein allow the replication of diffractive optics on curved substrates. This additional advantage eliminates the need for a plano optical interface further reducing the element count for a given optical system.

Abstract: The present invention relates to microstructures fabricated from semiconductor material and having a flexible member which is excited into various modes of resonance and in which such resonance is read optically. By coupling the microstructure to a surface or material of interest, a drive means will excite the flexible member into a characteristic resonance which when read optically gives indication of certain physical phenomena influencing the surface or material of interest. The microstructures of the present invention may be configured to self-resonate, as a so-called active device, under certain conditions. Many different physical phenomena may be quantified using the device of the present invention.

Abstract: In an energy recovery ventilator (ERV) for exchanging indoor air with outdoor air. The ERV having a housing including first and second input ports, and, first and second exhaust ports, and a heat exchanger core. The ERV further having a first blower for drawing indoor air into the ERV through the first input port, through the heat exchanger core and out the first exhaust port, and a second blower for drawing outdoor air into the ERV, through the second input port, through the heat exchanger core and out the second exhaust port. A means for defrosting the ERV is taught having a first bypass from the first exhaust port to the first input port and second bypass from the second exhaust port to the second input port. Dampers close the first exhaust port and the exhaust port when defrost of the heat exchanger core is needed.

Abstract: A programmable electronic thermostat which utilizes time and temperature pairs. This thermostat utilizes a first display which displays the current status information of the thermostat which includes the current time as well as the current temperature. A second display is incorporated in which the programmed information is included. This second display is located near the programming buttons and displays program information including the day, the period, the start time and the temperature setting. By separating the displays, the thermostat is easier to program and read.