Abstract:
A multi-spectral photodetector for detecting two or more different bands of infrared radiation is described. The photodetector includes a diffractive resonant optical cavity that resonates at the two or more infrared radiation bands of interest. By detecting infrared radiation at two or more discrete applied biases and by generating a spectral response curve for the photodetector at each of these biases, the response to each of the individual bands of infrared radiation can be calculated. The response to each band of infrared radiation can be found by deconvolving the response at each bias. The photodetector finds many uses including military and medical imaging applications and can cover a broad portion of the infrared spectrum.
Abstract:
A precision infrared detection device is provided, which is capable of measuring a wide range of temperature having a simple constitution, reduces the influence due to the dispersion among the operating points, and enables the cost down. The infrared detection device includes: reference voltage generation means 101 for generating a specific reference voltage; ambient temperature compensation means 102, to which a reference voltage from the reference voltage generation means 101 is applied, for outputting a signal for compensating the ambient temperature; first amplification means 103 for amplifying the signal outputted from the ambient temperature compensation means 102; infrared detection means 104, to which a signal outputted from the first amplification means 103 is applied, for converting infrared radiation energy into an electric signal; and second amplification means 105 for amplifying a signal outputted from the infrared detection means 104.
Abstract:
A method and a device is disclosed for illuminating a sample (1) and/or reference and collecting diffuse reflected and/or transflected radiation from the illuminated element and delivering it to a measuring equipment. The illuminating means (2A to 2H), when illuminating a sample or a reference, provide an extending illumination, coming from at least two positions. A movable reflecting element (4) is provided such that it in one position reflects the light from the illuminating means (2A to 2H) onto the sample or reference to be irradiated and reflects the diffuse reflectance and/or transflectance from the sample or reference to means (3) collecting the radiation.
Abstract:
THz imaging apparatus and methods are provided for rapidly and effectively examining a region of interest to determine the presence of specified compositions. The apparatus includes means for generating electromagnetic radiation of a desired terahertz frequency suitable for the examination, and for rendering the radiation incident at the region of interest. Detector means are provided at a plurality of points in a plane spaced from the region of interest, for detecting the terahertz radiation reflected from or transmitted through the region. Means are provided for converting the detected terahertz radiation to an image of the region of interest from which the presence of the specified compositions are determinable.
Abstract:
An optical measuring arrangement, particularly for quality control in continuous material flow processes, comprising a measuring head which is arranged immediately adjacent to a measurement object, a measurement light source which is held at the measuring head for illuminating a measurement spot on the measurement object, a measurement light reception device, at least one spectrometer which is optically coupled with the measurement light reception device via a light-conducting device, wherein the spectrometer and the light-conducting device are received in the measuring head, and a signal processing device which is likewise received in the measuring head. This results in a compact arrangement for reflection measurement which is easy to assemble and which, beyond this, supplies very accurate measurement results. Further, a measuring arrangement operating on the principle of spectroscopy is suggested for transmission measurement. The disclosure further relates to a combined reflection and transmission measurement device which carries out both measuring processes simultaneously.
Abstract:
A lightweight camera is provided that includes a lightweight lens system that has a reduced number of lenses. Reducing the number of lenses produces a lighter camera, but produces a distorted local image. The distorted local image is captured by the lightweight camera, and is preferably transmitted to a remote station. The remote station then performs image processing on the distorted image to remove at least some of the distortion in the image. Preferably, a Massively Parallel Richardson-Lucy (MPRL) algorithm is used to identify and remove distortion from the image. Also, motion, temperature and inter-detector difference distortion is detected and corrected.
Abstract:
A system for counting living beings moving on a first surface (0) and passing through a second cylindrical surface with substantially vertical generatrix, consists of N thermal radiating detection cells (11) having in particular a thermopile (30) including at least a sensitive element (31), and elements focusing (34) the thermal radiation and generating a field of vision (111) extended along a direction, the N detection cells (11) being distributed between two curves, one of the curves coinciding with the base line of the cylindrical surface crossed by the living beings, and the other curve being distant from the former one by a length D (42) equal to 5 cm at least, the direction of the extension of the field of vision of each cell being substantially tangent to one of the two curves.
Abstract:
A method of detecting objects with a night vision system is provided. The night vision system includes a light source and a camera. The method includes activating the light source as a sequence of light pulses wherein each light pulse is increasing in intensity for a predetermined number of pulses to form a pulse train. The camera is activated as a corresponding sequence of detection windows wherein each of the windows corresponds to one of the light pulses for receiving reflected light resulting from the corresponding light pulse. The light pulses and detection windows are configured such that a time delay between each corresponding light pulse and detection window is increasing throughout the pulse train. In another variation, the camera gain is increased throughout the pulse train. In yet another variation, the light pulses have constant amplitude, the camera gain is constant for all pulses, and the number of camera gain windows increases as the delay increases. In all cases, objects nearer the night vision system are imaged with lower intensity light, less camera gain, and/or fewer laser pulses than objects further away to provide a composite image in which the apparent brightness of near and far objects can be controlled.
Abstract:
Optical mapping apparatus in which a long, one or two dimensional detector array or higher resolution two dimensional array is synthesised using a two dimensional array (of shorter dimensions). The two dimensional array has an input mask having waveguides with a smaller input than output and the apparatus is adapted to scan the scene relative to the array to image different parts of the scene. In one embodiment the apparatus is adapted such that different parts of a line through the image which is perpendicular to the scan direction are imaged at different times as the detector array is scanned.