Abstract:
An infrared radiation detector includes a bolometer or micro-cantilever detector device which functions as a null detector in conjunction with electronic circuitry. The electronic circuitry senses a change in an output signal of the detector as the detector responds to infrared radiation incident upon the detector and provides a signal to a control element which provides a stimulus to the detector device to maintain the detector output signal at the same level. The element may be a piezoelectric element, a heater or a pair of electrodes and the corresponding stimulus may be stress, heat, or electrostatic change. The stimulus compensates for the effect of the infrared radiation and maintains the chosen detector output level at the same level. The nulling circuitry improves the linearity and dynamic range of the detector device.
Abstract:
A pyroelectric detector circuit comprises a pyroelectric sensor element connected to a load resistor and to an input of a buffer amplifier having a feedback path for multiplying the resistance of the load resistor at non-zero frequencies. This feedback enables the use of a smaller load resistor which is multiplied to produce a higher effective load resistance necessary for proper low frequency response of the detector circuit.
Abstract:
An outdoor light using a motion sensor that activates the light when motion is sensed by changes in the infrared signal detected. The device uses a passive infrared detector network to sense infrared and to produce an analog signal in response to said infrared detected which is then passed through an amplifier to a signal controlled oscillator. The signal is converted into a digital signal which is used to detect motion by a logic device.
Abstract:
A method and apparatus to reduce undesirable deficiencies in an image produced by a microbolometer array including multiple smaller arrays includes applying a separate bias pulse to each of the microbolometers in the smaller arrays and measuring a resulting signal corresponding to the applied bias pulse for each of the microbolometers using multiple measurement circuits associated with the smaller arrays during the frame time. Further, one or more known bias pulses are applied to the measurement circuitry during the frame time, one or more resulting calibration signals are measured, an offset parameter for each of the smaller arrays based on the corresponding measured resulting calibration signals is computed, and the measured resulting signal is corrected using the associated computed offset parameter to produce an output signal that reduces the undesirable deficiencies in the image produced by the array.
Abstract:
A system for improving the visibility in vehicles, including the following: an illumination optical system (2) for continuous radiation of infrared pulsed light; an associated receiver optical system (3) for receiving reflected components of the radiated light; a display (4) for representing information obtained by the receiver optical system (3), and a device (5, 6) for determining the presence of glare in the receiver optical system (3) from a foreign vehicle illumination optical system and for changing the keying interval or duty cycle of the infrared pulsed light of the illumination optical system (2) driven with fixed keying interval in dependence upon the vehicle direction of travel in such a manner that the glare is eliminated. Therein the illumination optical system is driven is driven with a fixed keying interval depending upon the vehicle direction of travel or, in certain cases, the direction of illumination. In an alternative embodiment, the illumination optical system (2) is operated at a wavelength which depends upon the vehicle direction of travel or, in certain cases, the direction of illumination.
Abstract:
A temperature dependent focal plane array operates without a temperature stabilization cooler and/or heater over a wide range of ambient temperatures. Gain, offset and/or bias correction tables are provided in a flash memory in memory pages indexed by the measured temperature of the focal plane array. The memory stores a calibration database, which is accessed using a logic circuit which generates a memory page address from a digitized temperature measurement of the focal plane array. The calibration database is comprised of an array of bias, gain and offset values for each pixel in the focal plane array for each potential operating temperature over the entire range of potential operating temperatures. The bias, gain and offset data within the database are read out, converted to analog form, and used by analog circuits to correct the focal plane array response.
Abstract:
A radiation thermometer is rationally adjusted during manufacturing processes instead of requiring a user to manually adjust the radiation thermometer each time a temperature is measured, and hence, the radiation thermometer better improves temperature measurement accuracy. The radiation thermometer comprises an infrared ray sensor for detecting an infrared ray from a measurement target; a temperature-sensitive sensor for generating a reference temperature signal; sensor output adjusting means for adjusting an output from the temperature-sensitive sensor and an output from the infrared ray sensor; temperature calculating means for calculating a temperature of the measurement target based on an adjusted temperature-sensitive sensor output and an adjusted infrared ray sensor output which are adjusted by the sensor output adjusting means; and temperature indicating means for indicating the temperature of the measurement target based on a signal from the temperature computing means, and the radiation thermometer is characterized in that the sensor output adjusting means comprises temperature-sensitive sensor absolute value adjusting means (ABS) for adjusting an absolute value of a characteristic of the temperature-sensitive sensor and infrared ray sensor sensitivity adjusting means (KAN) for adjusting a sensitivity of the infrared ray sensor.
Abstract:
A pyroelectric infrared array sensor has a pyroelectric element on which a plurality of sensing sections are formed, each of which has upper and lower electrodes which confront each other through the pyroelectric element. To fixedly secure the pyroelectric element to a substrate, lead conductors extended from sensing sections located adjacent to the edges of the light receiving surface of the pyroelectric element are fixedly connected to the substrate by conductive paste. The lower electrodes are connected to solder bumps on the substrate with conductive paste. The respective dimensions of the solder bumps can be adjusted so as to adjust the amount of heat conducted away from the sensing sections and thereby make the heat-sensitivity of the sensing sections more uniform. Alternatively or in addition, the amount of conductive paste used to connect the lower electrodes to the solder bumps can be adjusted for the same purpose.
Abstract:
A photodiode with integrated microporous filter formed on a semiconductor substrate is provided. The microporous filter will provide in excess of six orders of magnitude visible light reduction while transmitting a measurable amount of UV/EUV radiation. A process for manufacturing the photodiode with integrated microporous filter is also presented.
Abstract:
An infrared photo-detector focal plane array includes detectors with quantum well layers that are spectrally “tuned” to impinging radiation by modulating the voltage biases applied across each quantum well layer. Read out circuits, interfaced with each detector of the array, process the photo-currents received from each detector to determine the absolute temperature of the remote infrared source from which the impinging radiation originated.