Abstract: A medical treatment system, such as peritoneal dialysis system, may include control and other features to enhance patient comfort and ease of use. For example, a peritoneal dialysis system may include patient line state detector for detecting whether a patient line is primed before it is to be connected to the patient. The patient line state detector can also the ability to detect whether a patient line has been properly mounted for priming. Both patient line presence/absence and fill state can be determined using an optical system, e.g., one that employs a single optical sensor.

Abstract: A measurement system for a dry powder agent includes a sensor system which includes at least one sensor head at least partially within a powder calibration column and a control system in communication with the sensor system.

Abstract: A method detects metallic atoms in a fluid. The method includes: placing, in a zone sheltered from light, a photodiode comprising a photosensitive surface in contact with a fluid to analyze; heating the photosensitive surface of the photodiode to a temperature sufficient to allow metallic atoms deposited on the photosensitive surface to migrate through this surface; acquiring a signal relative to the lighting of the photodiode; and determining, from the acquired signal, a measurement representative of a contamination status by metallic atoms of the photodiode.

Abstract: An oscillating liquid lens and imaging system and method employing the lens are provided. The liquid lens includes a substrate with a channel opening extending therethrough between a first and second surface. A liquid drop is disposed within the channel and is sized with a first droplet portion, including a first capillary surface, protruding away from the first surface, and a second droplet portion, including a second capillary surface, protruding away from the second surface. The liquid lens further includes an oscillator operatively coupled to either the first droplet portion or the second droplet portion for oscillating the liquid drop within the channel. The imaging system, in addition to the oscillating liquid lens, also includes an image sensor coupled to an image path which passes through the first and second droplet portions for capturing one or more images through the oscillating liquid drop.

Abstract: A disinfecting device is proposed that is well suited for household and outdoor use. The device comprises a container housing 12 with an interior volume 24, which may contain an object or a liquid to be disinfected. The container housing 12 comprises a side wall 16 and an end cover 14. A dielectric barrier discharge lamp 32 is provided for emitting ultraviolet light into the volume 24. The lamp 32 comprises a lamp vessel 34 with gas filling and electrodes 42, 44 arranged electrically insulated from the gas filling. An alternating voltage applied to the electrodes 42, 44 causes a discharge in the gas filling. The lamp vessel 34 has a planar window from which during the discharge ultraviolet light 46 is emitted. The window is arranged in the end cover 14.

Abstract: A light sensor for detecting brightness of an outside of a vehicle includes: a light shielding element on a windshield; a light guiding element in a through hole of the light shielding element; and a light receiving element that receives light from the outside of the vehicle via the light guiding element and the windshield. The light guiding element includes an entrance surface facing the windshield and an output surface facing the light receiving element. The entrance surface receives the light from the outside. The light guiding element transmits and outputs the light from the output surface toward the light receiving element. The entrance surface has a top disposed inside of the through hole.

Abstract: An ultraviolet (UV) fluorometric sensor measures a chemical concentration in a sample based on the measured fluorescence of the sample. The sensor includes a controller, at least one UV light source, and at least one UV detector. The sensor emits UV light in a wavelength range of 245-265 nm from the light source through the sample in an analytical area. The UV detector measures the fluorescence emission from the sample. The controller transforms output signals from the UV detector into fluorescence values or optical densities for one or more wavelengths in the wavelength range of 265-340 nm. The controller calculates the chemical concentration of the chemical in the sample based on the measured fluorescence emissions.

Abstract: A method is provided for generating measurement parameters for a particle sample in a particle analyzer. The method includes, interrogating the particle sample with a triggering interrogator and one or more secondary interrogators respectively positioned along a length of an interrogation area, generating respective pulses based upon the interrogation of a first particle from the particle sample, determining a primary pulse detection window based upon a triggering pulse, determining a search interval to find a secondary pulse based upon factors including the primary pulse detection window and a laser delay, adjusting the search interval for laser delay variation dynamically based on the interrogation of the first particle, identifying the secondary pulse in the adjusted search interval, and processing the secondary pulse to determine a peak value of the secondary pulse. Corresponding apparatus are also provided.

Abstract: A fluid flow control system using flow rate changes to extract additional information from an in-line flow sensor. The system provides the ability to determine a position of a movable flow sensor element of a flow sensor by illuminating a photosensitive pixel array with a light source to create a first set of pixel intensity values introducing an abrupt change to the fluid driving pressure, illuminating the photosensitive pixel array with a light source to create a second set of pixel intensity values, and calculating the difference between the first and second sets of pixel intensity values as a function of pixel position.

Abstract: This invention relates to a compact cavity ring down spectrometer for detection and measurement of trace species in a sample gas using a tunable solid-state continuous-wave mid-infrared PPLN OPO laser or a tunable low-power solid-state continuous wave near-infrared diode laser with an algorithm for reducing the periodic noise in the voltage decay signal which subjects the data to cluster analysis or by averaging of the interquartile range of the data.

Abstract: The invention relates to a device and a method for the continuous optical determination of the fill level of liquids in a liquid tank of a vehicle or airplane which have a refractive index of at least 1.33 at room temperature and at a wavelength of 589 nm. The device has an elongate measurement channel (3) which can be arranged on or in a liquid tank. A light emitting means (8, 8?) is arranged such that light (13, 14) emitted by the light emitting means (8, 8?) is introduced into the measurement channel (3). A detector arrangement (12, 8?) is arranged such that light (10) emitted into the measurement channel (3) by the light emitting means (8, 8?) is incident on the detector arrangement (12, 8?). The wall (15) which defines the measurement channel (3) is designed such that the reflection coefficient for light of the predetermined wavelength or from the predetermined wavelength range is at least 70%, at least for an angle of incidence up to a predetermined limit angle.

Abstract: A hydrocarbon presence sensor used to detect for the presence of a fuel in a buffer cavity of an inter-propellant seal. A sensor is formed on a rotor shaft in the buffer cavity and an optical imaging device is used to view a change in appearance of the sensor when a hydrocarbon forms on the surface. In one embodiment, the sensor is a coating of porous silicon. In other embodiments, the sensor can be a mirrored or frosted surface on the shaft. A white light source or a laser is reflected off of the sensor and an optical imaging device reads the reflected light to detect for a change in color or intensity of the light to indicate if a hydrocarbon is present on the sensor surface.

Abstract: A method for discriminating particle groups comprises generating, by a particle analyzer, a particle characteristic distribution histogram in which the abscissa indicates respective channels for representing the characteristics of the particles, and the ordinate indicates the particle count; setting a valid area selection height in the particle characteristics distribution histogram; and generating an equivalent negative histogram based on the set height and the particle characteristic distribution histogram.

Abstract: A real-time in-situ sensor system is provided for measurement of bioluminescence and determination of bioluminescence surface signature. The system measures bioluminescence in the wake of a submerged moving object as well as ambient light levels outside of the wake. Along with measurements of depth and water-quality parameters including turbidity, temperature and salinity, the surface signature of the induced underwater bioluminescence can be calculated by considering light transmission and attenuation through water. With this real-time information, the operator of the submerged moving object can employ tactical maneuvers to affect the resultant surface signature.

Abstract: Embodiments provide an optical sensor head and method of making an optical sensor head. In some cases the sensor head can be used as a fluorometric sensor to measure concentrations of substances within a liquid sample of interest. The sensor head includes a light source window and a detector window that transmit light between the sensor head and an analytical area. In some cases the windows include a ball lens positioned within a channel such that the ball lens and the channel create a seal between the interior and exterior of the sensor head.

Abstract: Methods and systems are provided for monitoring a solid-liquid interface, including providing a vessel configured to contain an at least partially melted material; detecting radiation reflected from a surface of a liquid portion of the at least partially melted material; providing sound energy to the surface; measuring a disturbance on the surface; calculating at least one frequency associated with the disturbance; and determining a thickness of the liquid portion based on the at least one frequency, wherein the thickness is calculated based on L=(2m?1)vs/4f, where f is the frequency where the disturbance has an amplitude maximum, vs is the speed of sound in the material, and m is a positive integer (1, 2, 3, . . . ).

Abstract: An apparatus (10) for analyzing a fluid (18) of volume V comprises—a filter (12) having a filter surface (14) or area A, the filter being capable of allowing the fluid to flow through the filter surface, the fluid's volumetric flow density, averaged over the filter surface, being jmean; and—a scanner for scanning the filter surface with a scan rate B; wherein the area A substantially coincides with an optimum area Aopt defined as Formula (I). The sum of a filtering time and a scanning time may thereby be minimized. In another aspect, an apparatus (10) comprises—a set of at least two filters, each filter in the set of filters having a filter surface of area A and being capable of allowing the fluid to flow through the filter surface, the area A having a different value for each of the filters; and—a mechanism for selecting one (12) of the filters and placing the selected filter (12) in an operating position; and—a scanner for scanning the filter surface face (14) of the selected filter (12).

Abstract: A method of determining auto-calibrating information of a test sensor includes providing an optical read head that includes a light source, a light guide and a detector. The read head forms an opening that is sized to receive a test sensor. The detector includes a linear-detector array or single detector. A test sensor is provided having apertures formed therein. The test sensor is placed in the opening of the optical read head. Light is transmitted from the light source through the apertures. The light transmitted through the apertures using the detector or detecting the absence of light being transmitted through the test sensor using the detector is detected. The detected light or the absence of detected light information from the detector is used to determine the auto-calibration information of the test sensor.

Abstract: An ultraviolet (UV) fluorometric sensor measures a chemical concentration in a sample based on the measured fluorescence of the sample. The sensor includes a controller, at least one UV light source, and at least one UV detector. The sensor emits UV light in a wavelength range of 245-265 nm from the light source through the sample in an analytical area. The UV detector measures the fluorescence emission from the sample. The controller transforms output signals from the UV detector into fluorescence values or optical densities for one or more wavelengths in the wavelength range of 265-340 nm. The controller calculates the chemical concentration of the chemical in the sample based on the measured fluorescence emissions.

Abstract: An article includes a substrate assembly for use in a detector system. The substrate assembly includes a substrate; a sample reception structure secured to the substrate; a test window extending through the substrate; and a fluid channel defined by a surface of the substrate and extending from the sample reception structure to the test window.

Abstract: A method for determining quantity and/or a type of dust control agent for controlling dust of a bulk material or flowability thereof comprises dispensing a bulk material into an agitator and agitating the bulk material in the agitator to create airborne dust from the bulk material. A test method for determining a quantity and/or a type of dust control agent effective for reducing a quantity of airborne dust that separates from a bulk material during handling comprises: 1) dispensing a dust-containing bulk material into an agitator; 2) agitating the bulk material in the agitator to a degree sufficient to produce airborne dust from the bulk material; and 3) measuring a quantity of airborne dust produced from the bulk material; repeating steps 1), 2) and 3) after applying a particular dust control agent to said bulk material; and comparing the quantity of airborne dust that separates from the bulk material with and without the dust control agent.

Abstract: The invention relates generally to methods of monitoring and controlling the processing of blood and blood samples, particularly the separation of blood and blood samples into its components with a two-dimensional optical measurement and control device. The method may comprise the steps of providing a blood processing system comprising a density centrifuge blood processing system and an elutriation blood processing system; filling the elutriation blood processing system with a desired component; measuring a cellular flux of cells entering the elutriation blood processing system with a two-dimensional optical control system; and flushing the elutriation blood processing system.

Abstract: An apparatus for monitoring a position of a semiconductor process fluid interface in a dispense nozzle includes an extended optical source adapted to provide an optical beam propagating along an optical path. The optical beam is characterized by a path width measured in a first direction aligned with a dispense direction. The apparatus also includes an optical detector coupled to the optical path and adapted to detect at least a portion of the optical beam and a dispense nozzle disposed along the optical path at a location between the extended optical source and the optical detector. The apparatus further includes a nozzle positioning member coupled to the dispense nozzle and adapted to translate the dispense nozzle in the first direction.

Abstract: The invention relaters to a device (100) for biological analysis by measurement of photoluminescence in a fluid in a measurement tank (111). This device (100) comprises at least two light sources (121, 131) adapted to emit in different spectral areas respectively appropriate for measurement of absorption and fluorescence, and a sensor device (140) comprising a sensor (141), an optical system (142), and filter means (144), which three elements are mutualized in accordance with the invention to enable absorption and/or fluorescence to be measured. In accordance with the invention the internal gain of the sensor (141) is configurable to enable the fluorescence and absorption measurements to be executed sequentially.

Abstract: Techniques for smoke detection are provided. In one aspect, an exemplary smoke detection device is provided. The smoke detection device comprises an infrared beam transmitting unit; an infrared beam receiving unit; and a control module associated with the infrared beam transmitting unit and the infrared beam receiving unit. The infrared beam transmitting unit and the infrared beam receiving unit are configured to communicate with each other, via an infrared beam, and with the control module, via a signal produced in response to smoke being present at a level that is greater than a threshold smoke level.

Abstract: The invention relates generally to methods of monitoring and controlling the processing of blood and blood samples, particularly the separation of blood and blood samples into its components. In one aspect, the invention relates to optical methods for measuring two-dimensional distributions of transmitted light intensities, scattered light intensities or both from a separation chamber of a density centrifuge. The method may include performing first and second measurements of an operating condition; analyzing the first and second measurements using a predictive data analysis algorithm; comparing the predicted operating condition to a desired operating condition; and adjusting at least one setting.

Abstract: A fluorescence detection system for measuring biomolecules is disclosed, which includes a fluorescence detection device, a light source, a sample-loading unit, and an analysis-reading device. The fluorescence detection device has a substrate and plural phototransistors arranged on the substrate, and each phototransistor contains an emitter, a collector locating on the substrate, and a base between the emitter and the collector. The base-collector diode junction functions as an absorber to convert fluorescence to photocurrent. The light source serves to excite a fluorescent dye contained in a biomolecule sample. The sample-loading unit is used to load or transport the excited biomolecule sample onto a sensing zone of the fluorescence detection device. The analysis-reading device is to measure photocurrent output from the fluorescence detection device under a bias. Hence, the biomolecule content can be easily determined by the fluorescence detection system.

Abstract: A system having a multiple-mirror ring-down cavity with one mirror where light may be input into the cavity and light from the cavity may be detected. A valve may permit light to enter or not to enter the cavity. An amplifier may be connected to a detector for detecting light from the cavity. The amplifier may be off or set at a low gain when light is entering the cavity and be on at a medium or high gain at a time when light is not entering the cavity.

Abstract: An apparatus for detecting one or more substances includes a radiation source emitting a beam of radiation and also includes a material capable of reflecting the beam of radiation with a first characteristic and capable of reflecting the beam of radiation with a second characteristic when the material interacts with the one or more substances. The apparatus also includes two or more radiation detectors to detect the first and second characteristics of the beam of radiation. A first one of the two or more radiation detectors is adjustably aligned to detect the first and second characteristics of the beam of radiation reflected from a first region of the material. A second one of the two or more radiation detectors is adjustably aligned to detect the first and second characteristics of the beam of radiation reflected from a second region of the material.

Abstract: The present invention provides an apparatus and method for detecting components of a mixed gas which increases the detection efficiency using a sensor array in which various types of nanomaterials such as carbon nanotubes (CNT), zinc oxide (ZnO), titanium dioxide (TiO2), and tin dioxide (SnO2) which are sensitive to environment, so as to detect various components of a mixed gas using the characteristics that the effective refractive index change of the sensors induced by the gas adsorption depends on the apecies of nanomaterials and a concentration change in detected materials, thus effectively detecting the components of a mixed gas by the single detection without an inefficient education process required for conventional pattern recognition.

Abstract: A fluid flow control system using flow rates to extract additional information from an in-line flow sensor. The system provides the ability to determine a position of a movable flow sensor element of a flow sensor by illuminating a photosensitive pixel array with a light source to create a first set of pixel intensity values introducing an abrupt change to the fluid driving pressure, illuminating the photosensitive pixel array with a light source to create a second set of pixel intensity values, and calculating the difference between the first and second sets of pixel intensity values as a function of pixel position.

Abstract: An instrument detects an amount of a component of a sample gas by passing an excitation light through the sample gas at atmospheric pressure to produce fluorescence light from the component. The fluorescence light is discriminated using a sequence of multiple long pass interference filters to filter out the excitation light. The discriminated fluorescence light is then detected to produce a signal representative of the amount of the component in the sample gas. Preferably, the excitation light is continuously passed through the sample gas. In one embodiment, the gas flows through a cell having a parabolic reflector as an interior surface and a source of the excitation light at a focus of the parabolic reflector. In other embodiments, multiple components are detected in parallel using multiple sample cells and a fiber optic multiplexer to sequentially filter and detect the fluorescence light from each of the multiple sample cells.

Abstract: A fluid overfill probe is resistant to failure caused by physical stresses resulting from thermal expansion of probe components. A fluid level detector is connected to circuit components that are mounted on a circuit board located in a housing of the probe. The circuit board is located within a tube that is positioned within, and secured to the housing, and the circuit board is secured to an inner surface of the tube along its edges. The tube has a shape and rigidity sufficient to maintain a gap between the circuit components and the inner surface of the tube such that thermal expansion of probe components result in no physical stress to the circuit components.

Abstract: Aerosol and hydrosol particle detection systems without knowledge of a location and velocity of a particle passing through a volume of space, are less efficient than if knowledge of the particle location is known. An embodiment of a particle position detection system capable of determining an exact location of a particle in a fluid stream is discussed. The detection system may employ a patterned illuminating beam, such that once a particle passes through the patterned illuminating beam, a light scattering is produced. The light scattering defines a temporal profile that contains measurement information indicative of an exact particle location. However, knowledge of the exact particle location has several advantages. These advantages include correction of systematic particle measurement errors due to variability of the particle position within the sample volume, targeting of particles based on position, capture of particles based on position, reduced system energy consumption and reduced system complexity.

Abstract: In one embodiment, a drop ejector assembly includes a printhead, a drop zone immediately downstream from the printhead, an array of optical fibers exposed to the drop zone such that light scattered off drops in the drop zone illuminates at least some of the optical fibers in the array, and a photo detector operatively connected to the array of optical fibers for converting light from the optical fibers into an electrical signal. In another embodiment, a drop detector includes a light source for illuminating drops passing through a drop zone and a light sensor for sensing light scattered off drops in the drop zone. The length of drop zone is 3 mm or less and the light sensor has a cross sectional dimension less than the length of the drop zone.

Abstract: The present invention provides a method of operating an infrared drip sensor in an enteral pump system to reduce false alarm conditions. The method consists of the following steps: optically coupling a infrared beam emitter with an infrared beam detector along an infrared beam path that extends through a drip chamber and intersects the drip path; monitoring the output signal of the infrared beam detector to detect pulses; monitoring the pulses for an interruption thereof; and running an infrared beam power update routine when an interruption is detected in the pulses, the infrared beam power update routine consisting of incrementally increasing a power level of the infrared beam until the power level of the infrared beam is sufficient to re-establish an output signal at the infrared beam detector.

Abstract: A moisture removal apparatus and method of an image read-out apparatus, in which the image read-out apparatus includes a contact image sensor (CIS) provided with a document glass on which a document is put on an upper portion thereof and a read-out unit to read out an image of the document, and a pressing roller rotatably provided in contact with a top surface of the CIS to press and transfer the document. The moisture removal apparatus includes a heater to heat the document glass at a predetermined temperature to remove moisture, a power source to apply a predetermined voltage to the heater, a sensing unit to provide basic information to determine driving conditions of the heater, and a controller to control heating conditions of the heater on the basis of the information received from the sensing unit. Thereby, the moisture on the top surface of the document glass may be effectively removed.

Abstract: An optical tweezers controlling device including a light source, an objective lens and a focus adjusting unit is provided. The focus adjusting unit disposed between the light source and the objective lens includes a mirror set and a zoom lens set. The mirror set has at least a mirror. The mirror is rotatable such that after a light of the light source is projected to the mirror, the reflective direction of the light reflected from the mirror is changeable. The zoom lens set has at least a zoom lens disposed in accordance with the mirror. By rotating the mirror or changing the focal length of the zoom lens, the focusing location of the light changes on the focal plane of the objective lens or in the front or the rear of the focal plane.

Abstract: A diagnostic test device comprises means for sampling a liquid biological sample and means for reacting the sample with at least one reagent to provide one or more visible indicia. The device also comprises an optical detector for detecting the presence of the one or more indicia. The device also comprises means for causing at least part of the optical detector to move over the one or more indicia.

Abstract: An apparatus and a method for changing optical tweezers are provided. The apparatus includes a diffractive optical element (DOE), a mask unit and an objective lens. The DOE includes a plurality of phase delay patterns. The mask unit includes a plurality of mask patterns that correspond to the phase delay patterns, respectively, wherein at least a portion of the mask patterns are complementary. A laser beam passing through each phase diffractive pattern correspondingly passes through each mask pattern to generate a compound diffractive pattern. The objective lens receives the compound diffractive pattern and focuses it on an examining object to form an optical tweezers.

Abstract: Improved optical alignment precision to a passive optical cavity is provided by including a combination of a weak focusing element and a translation plate in the input coupling optics. Adjustment of positions and angles of these optical elements, preferably after all other input optical elements are fixed in place, advantageously provides for high-precision optical alignment to the cavity, without requiring excessively tight fabrication tolerances. Fabrication tolerances are relaxed by making the optical power of the weak focusing element significantly less than the optical power of a strong focusing element in the input optics. The position and angles of the beam with respect to the cavity can be adjusted, as can the size of the beam at the cavity. Differential adjustment of the beam size in two orthogonal directions (e.g., tangential plane and sagittal plane) at the cavity can also be provided.

Abstract: A filter arrangement can transmit and/or reflect light emanating from a moving object so that the emanating light has time variation, and the time variation can include information about the object, such as its type. For example, emanating light from segments of a path can be transmitted/reflected through positions of a filter assembly, and the transmission functions of the positions can be sufficiently different that time variation occurs in the emanating light between segments. Or emanating light from a segment can be transmitted/reflected through a filter component in which simpler transmission functions are superimposed, so that time variation occurs in the emanating light in accordance with superposition of two simpler non-uniform transmission functions. Many filter arrangements could be used, e.g. the filter component could include the filter assembly, which can have one of the simpler non-uniform transmission functions.

Abstract: A diagnostic test device comprising means for sampling a liquid biological sample, means for reacting the sample with at least one reagent to provide one or more visible indicia and an optical detector for detecting the presence of said one or more indicia, the device further comprising a releasable tether which is released by contact with the liquid sample, thereby to cause the optical detector to detect the said one or more indicia.

Abstract: The present invention provides a method of operating an infrared drip sensor in an enteral pump system to reduce false alarm conditions. The method consists of the following steps: optically coupling a infrared beam emitter with an infrared beam detector along an infrared beam path that extends through a drip chamber and intersects the drip path; monitoring the output signal of the infrared beam detector to detect pulses; monitoring the pulses for an interruption thereof; and running an infrared beam power update routine when an interruption is detected in the pulses, the infrared beam power update routine consisting of incrementally increasing a power level of the infrared beam until the power level of the infrared beam is sufficient to re-establish an output signal at the infrared beam detector.

Abstract: The invention relates to a method and a microelectronic sensor device for making optical examinations in an investigation region (3). An input light beam (L1) is emitted by a light source (20) into said investigation region (3), and an output light beam (L2) coming from the investigation region (3) is detected by a light detector (30) providing a measurement signal (X). An evaluation unit (40) provides a result signal (R) based on a characteristic parameter (e.g. the intensity) of the input light beam (L1) and the output light beam (L2). Preferably, the input light beam (L1) is modulated with a given frequency (?) and monitored with a sensor unit (22) that provides a monitoring signal (M). The monitoring signal (M) and the measurement signal (X) can then be demodulated with respect to the monitoring signal, and their ratio can be determined. This allows to obtain a result signal (R) that is largely independent of environmental influences and variations in the light source.

Abstract: The invention provides an optical drop detection system (10), for a low-flow metering device of the type having a drop generator 12, 24, (19), the system comprising at least one optical transmitter (26) which produces a plurality of light beam pulses (28) of microsecond duration and at millisecond intervals, and at least one optical receiver (33) positioned to register receipt of the light pulses (28) transmitted through the path of drops (18) generated by the drop generator (12, 24, 19) and to record the number of pulses which hit a given drop and which do not register on the receiver (32), the frequency and strength of the pulses being calibrated so that a single drop is impinged upon by a plurality of pulses, and further comprising automatic feed-back means for adjusting the parameters of interaction between the at least one optical transmitter (26) and the at least one optical receiver (32) to produce and maintain a predetermined minimum and a predetermined maximum number of hits per drop.

Abstract: Methods and systems are provided for monitoring a solid-liquid interface, including providing a vessel configured to contain an at least partially melted material; detecting radiation reflected from a surface of a liquid portion of the at least partially melted material that is parallel with the liquid surface; measuring a disturbance on the surface; calculating at least one frequency associated with the disturbance; and determining a thickness of the liquid portion based on the at least one frequency, wherein the thickness is calculated based on L = f 2 ? w 2 g , where g is the gravitational constant, w is the horizontal width of the liquid, and f is the at least one frequency.

Abstract: The invention relates to a method and device (1) for imaging an interior of a turbid medium (55). A turbid medium (55) inside a measurement volume (15) is irradiated from a plurality of source positions (25a) with light from a light source (5), and light emanating from the measurement volume (15) is detected from a plurality of detection positions (25b). An image of the interior of the turbid medium (55) is reconstructed from the detected light. In both the method and the device (1), detector signals can be amplified for each source position-detection position pair by a multi-gain amplification unit comprising an amplifier circuit (60). The amplification factor is selected from a number of possible amplification factors based on detected signal strength in the prior art. According to the invention, however, the method and device are adapted such that the amplification factor is selected for at least one source position-detection position pair on the basis of an estimate of expected electrical signal strength.

Abstract: Apparatus (1) for environmental monitoring, allowing to determine the mass concentration of air-dispersed particulate matter by operating or spy filters (F1-F6), comprising a beta radiation emitter (16) and detector (18) for detecting the mass of particulate matter settled on the operating or spy filters (F1-F6), wherein it is further provided the same beta measurement on spy filters (S 12-S1 6) exposed to the same environmental conditions of the operating filters (F1-F6) and the determination of in-air particulate matter concentration by compensation of the two measurements.

Abstract: A light scattering type smoke sensor includes a sensor body, light-emitter for emitting light toward an open smoke-sensing space and outputting a light-received signal according to the amount of scattering light received, and a fire judging unit for judging whether fire occurs or not on the basis of the amount of received light determined on the basis of the outputted light-received signal.