Abstract:
A light-controlled oscillator includes a circuit device, a detection circuit and a control circuit. The circuit device changes its characteristics when light is applied, so that a frequency of the oscillation shifts. The detection circuit detects a change of the characteristics caused according to the applied light. The control circuit controls an operation of the oscillator to increase a shift of the frequency of the oscillation according to the change of the characteristics. The oscillation frequency can be shifted by a desired amount only by detecting a change of characteristics based on a condition of the light, even when the intensity of the light is small.
Abstract:
There is provided an infrared sensor unit for deactivating an electrical appliance when left unattended by its user. The sensor unit includes a passive infrared sensor for sensing the user through a field of infrared light provided within a viewable distance of the electrical appliance. An adjustable timer is in electrical communication with the passive infrared sensor for counting toward a predetermined amount of time when the user is not sensed within the field of infrared light. The sensor unit further includes a controller device which is in electrical communication with the adjustable timer for deactivating the electrical appliance upon reaching the predetermined amount of time.
Abstract:
A first thermistor 8 and a second thermistor 9 are arranged forwardly and rearwardly of a thermopile sensor 5. A thermopile chip 55 is arranged and interposed between the first thermistor 8 and an integrated thermistor 57. A sensor cover is mounted in contact with front and side portions of a can portion 59 of a thermopile casing 56. A temperature or a radiant quantity of infrared rays on the front portion of the can portion is estimated from a temperature change of the integrated thermistor per second.
Abstract:
A hot melt adhesive sensing system and methods including detecting (410) multiple areas of a target, for example a hot adhesive material, by sensing changes in temperature with a corresponding number of thermal sensors, summing (420) an output of the thermal sensors, and evaluating (430) the summed output by comparing the summed output with a reference, the results of which may be assessed relative to a specified tolerance.
Abstract:
A method of generating an image sequence that includes the steps of detecting scene irradiance using detectors in a focal plane array, generating an output image sequence for each of the detectors based on the detected irradiance, and correcting the output image sequence generated by a first subset of detectors in the focal plane array and the output image sequence generated by a second subset of detectors in the focal plane array using the correction provided to the first subset of detectors.
Abstract:
This invention consists of a radiation sensor with a thermal cycling and synchronous readout scheme. It is intended for use with pyro-optical materials which exhibit a phase transition that is hysteric. A preferred material is vanadium oxide which has a semiconductor-metal phase transition typically at 68 deg C. and a hysteresis of a few degrees C. depending on material processing. The temperature of the pyro-optical film is cycled in synchronization with readout electronics to achieve a reset reference for the readout once each repetitive cycle. When the thermal cycle is divided into two regions, a reference and a biased frame are obtained. The readout electronics compare the reference frame the biased frame to obtain a desired difference which is an unbiased frame.
Abstract:
An on-engine radiation thermometer that simultaneously measures, through a common optical waveguide probe, long wavelength infrared radiation and short wavelength radiation, enables accurate temperature measurement and condition monitoring of ceramic thermal barrier coatings used on metal blades of gas turbine engines. This in turn enables operation at higher combustion temperatures, thereby optimizing coating use, and provides warning signals that are indicative of potential blade failure due to barrier coating spall and other conditions.
Abstract:
A passive infrared sensor uses two detectors having elements of different configurations such that each element outputs a respective frequency when an object moves in front of it. Based on the presence of two frequencies with similar peak and/or slope characteristics, a motion signal is output to, e.g., activate an alarm. In another embodiment the detectors have plural elements with the elements of one detector being wired in a dimension that is orthogonal to the dimension in which the elements of the other detector are wired. The signals from the detectors are combined to determine motion and size of object. The detector elements can also be configured differently from each other as in the first embodiment, and the polarities of signals can be used to determine direction of motion. In yet another embodiment the detectors can be of the same size but have optics of different focal lengths.
Abstract:
Optical methods and devices for measuring temperature and a secong physical parameter, using a single photoluminescent probe material comprised of a single luminophor, and methods and devices for determining temperature-corrected values of said second physical parameter, which can be an oxygen or air pressure or a parameter chosen from the group comprising an electrical current, a magnetic field and an electrical field or voltage. The luminophor is excited sequentially by a first excitation light of chosen first wavelengths and intensity P1 which generates a first luminescence light of intensity I1, and a second excitation light of chosen second wavelengths and intensity P2 which generates a second luminescence light of intensity I2. The ratio (I2.P1/I1.P2) varies substantially in a known manner with varying temperature, substantially independent of the magnitude of said second physical parameter, thus providing a temperature correction factor to the measurement of said second physical parameter.
Abstract:
The invention concerns an infrared sensor (2) comprising a plurality of pixels (12) having a structured layer (20) for infrared light absorption located at the sensor upper surface. The invention is characterised in that the absorption layer (20) is formed of colloidal particles, in particular graphite or metal oxide wafers embedded or sealed in a binder. The method for making such a sensor consists in forming the structured layer by deposit of the colloidal particles in accordance with a standard technique and then in eliminating partly the thus formed absorption layer to obtain a plurality of elementary absorption zones respectively associated with the plurality of pixels.