Abstract: The invention provides a glare reduction apparatus disposed in an object illuminated by a light source. The glare reduction device includes an electro-optical device covering a surface of the object. A light sensing device is disposed on a first fixed point of the object. A controller is electrically coupled to the electro-optical device and the light sensing device, wherein the controller calculates a corresponding light sensing position of the electro-optical device according to a light sensing position of the light sensing device which directly receives light from the light source, to reduce the light transmittivity of the corresponding light sensing position of the electro-optical device to generate a light shielding region. The light shielding region attenuates the light from the light source to a second fixed point of the object.

Abstract: At least one cell implementing a sensor array embraces a photoelectric-conversion accumulation element configured to generate and accumulate signal charges, a potential detection circuit configured to detect the signal charges generated by the photoelectric-conversion accumulation element as a potential change, and an amplification circuit configured to amplify the potential change and to transmit to an output-signal line. The photoelectric-conversion accumulation element and the potential detection circuit are connected in series between a first potential terminal and a second potential terminal, and the potential detection circuit has an insulated-gate transistor, which detects the potential change in a weak inversion state, in a period when an optical-communication signal is received.

Abstract: A display device according to the present invention includes: a plurality of pixels arranged in matrix; photoelectric elements being provided in each of the pixels and each outputting a signal with a value according to the quantity of light received by the photoelectric element, the photoelectric elements forming photoelectric element groups (PDs(n)) in each of which the photoelectric elements arranged along a one-dimensional direction are grouped; and resetting wirings (Vrts(n+1)), each of which is connected to the anode side electrodes of the photoelectric elements in the corresponding one (PDs(n)) of the photoelectric element groups commonly, and is shared by an adjacent one (PDs(n+1)) of the photoelectric element groups. This configuration makes it possible to provide such a display device having a pixel including an optical sensor incorporated therein, that is not affected by the resolution and the performance of an output AMP and is capable of preventing a decrease in the aperture ratio of the pixel.

Abstract: An apparatus includes a first photoelectric conversion element configured to convert light into a current by a photoelectric conversion, a first current amplification unit configured to amplify the current, a first current monitoring unit configured to monitor the amplified current amplified and output a monitor signal, and a first bias voltage setting unit configured to gain the monitor signal by a factor less than 1 and apply a reverse bias voltage to the first photoelectric conversion element according to the gained monitor signal.

Abstract: An optical receiver device including: a light-receiving element having a first electrode acting as an outputting electrode and a second electrode coupled to a potential that is different from a ground potential; an amplifier device having an amplifier element, a connection terminal including a signal electrode and a ground electrode on an upper face thereof; a first conductor coupling a potential of the first electrode of the light-receiving element to the signal electrode, the first conductor being introduced from the upper face side of the amplifier device; and a second conductor coupling a potential of the second electrode of the light-receiving element to the ground electrode, the second conductor introduced from the upper face side of the amplifier device.

Abstract: A semiconductor growth system includes a chamber and a source of electromagnetic radiation. A detector is arranged to detect absorption of radiation from the source by a chloride- based chemical of the reaction chamber. A control system controls the operation of the chamber in response to the absorption of radiation by the chloride-based chemical. The control system controls the operation of the chamber by adjusting a parameter of the reaction chamber.

Abstract: A method for detecting an object located in an environment and a multi-channel LED object detection system for detecting an object located in an environment are provided.

Abstract: An optoelectronic sensor (10), in particular a light barrier having a light transmitter (14) for the transmission of a light beam (18) and a light receiver (26) arranged facing the light transmitter (14) at an alignment angle to transform the received light beam (18) into an electrical received signal is provided, wherein the transmission power of the light transmitter (14) and/or the reception sensitivity of the light receiver (26) is/are set, such that the received signal has an intensity distribution varying in accordance with the alignment angle and wherein an evaluation unit (28) of the sensor (10) is configured to determine by means of the received signal whether the light beam (18) is interrupted or not.

Abstract: An apparatus and method for receiving electrical signals and transmitting optical signals includes a substrate having an electrical circuit. An electrical-to-optical module is mounted on the substrate, and the module includes an array of photodetectors communicating with the electrical circuit. The photodetectors may include VCSEL arrays or PD arrays. The module receives electrical signals from the electrical circuit and provides a plurality of corresponding light signals. An electrical transport is embedded in the substrate, and the electrical transport electrically communicates with the array of photodetectors. An optical interface provides electrical communication between an optical fiber and the electrical circuit. A heat transfer device may be positioned adjacent the photodetectors to transfer heat generated by the photodetectors.

Abstract: The invention provides imaging apparatus and methods useful for obtaining a high resolution image of a sample at rapid scan rates. A rectangular detector array having a horizontal dimension that is longer than the vertical dimension can be used along with imaging optics positioned to direct a rectangular image of a portion of a sample to the rectangular detector array. A scanning device can be configured to scan the sample in a scan-axis dimension, wherein the vertical dimension for the rectangular detector array and the shorter of the two rectangular dimensions for the image are in the scan-axis dimension, and wherein the vertical dimension for the rectangular detector array is short enough to achieve confocality in a single axis.

Abstract: A device for scanning a document is provided. A document placed on a support surface is scanned line by line by a camera that is provided with an optoelectronic line sensor, and electric signals are produced. The line sensor includes a plurality of image recording elements disposed in a linear orientation. A lens system is used to image the light reflected by the document to be captured onto a part of the image recording elements.

Abstract: The present invention provides an optical sensor at least some part of which is formed monolithically in an active matrix substrate of a display device. In order to detect ambient light with high accuracy by eliminating the influences of stray light and of property variations between photodetecting elements, the optical sensor includes a detection photodiode (11) and a reference photodiode (12) covered with a shielding film (15). The optical sensor further includes a differential amplifier (16) one input terminal of which is connected to the cathode of the detection photodiode (11) and the other input terminal is connected to the cathode of the reference photodiode (12), an integration capacitor (19) and a reset switch (22).

Abstract: An amplifier circuit and an optical pickup device supporting multi-layered optical discs and hi-speed play mode. The amplifier circuit includes photodiodes 11 to 15; operational amplifiers 21 to 25; feedback resistors 31 to 34; resistors 41 to 45; output terminals 51 to 55; reference voltage sources 56 and 57; a reverse-bias-voltage control circuit 61; and a parasitic-capacitance detecting circuit 65. The reverse-bias-voltage control circuit 61 is connected to the cathodes of the photodiodes 11 to 15. The parasitic-capacitance detecting circuit 65 detects the parasitic capacitance of the photodiode 15. The reverse bias voltage generated in the reverse-bias-voltage control circuit 61 is adjusted according to the detection result by the parasitic-capacitance detecting circuit 65, so that the optical sensitivity of the photodiodes 11 to 14 is maintained at an appropriate value.

Abstract: A data processing circuit includes a data processing unit including two signal-conversion circuits and controlled switches connected to inputs and outputs of the conversion circuits. The data processing unit further includes a binary signal inlet, a binary signal outlet, and a memory unit. The memory unit includes capacitors each storing a binary piece of data. The capacitors are connected to a memory bus via switches. The bus is connected to the processing unit. In response to control signals provided to the controlled switches, the data processing unit performs at least the following operations: writing a binary datum in a capacitor, reading from a capacitor a binary datum stored therein and applying the datum to an output, and logically combining binary data stored in at least two capacitors.

Abstract: A detection sensor to detect a receiving position of laser light according to the present invention includes a pair of light receiving element arrays (11X and 11Y), wherein adjacent light receiving elements (PDXi) are positioned as spaced equidistantly from one another and are mutually connected via a resistor (RXj), and wherein the output lines (11a and 11b) are respectively connected to the light receiving elements that are present at both ends of the respective light receiving element arrays (11X and 11Y). The light receiving element arrays (11X and 11Y) configure a composite array wherein the light receiving elements of a first light receiving element array are respectively positioned between the mutually adjacent light receiving elements of a second light receiving element array.

Abstract: A detector array for use in a laser imaging apparatus, comprises a plurality of housings disposed in an arc around an opening in which an object to be scanned is disposed, each housing including an open front end, a rear end and a longitudinal axis; and a detector disposed within each housing at a distance from the front end, thereby to restrict the field of view of each detector. The housings are adapted to be orbited around the object about an orbit axis. Each detector is adapted to simultaneously detect light exiting from the object within the respective field of view of each detector. A method for collecting light exiting from a object being scanned with a light source is also disclosed.

Abstract: A proximity sensor is disclosed. The proximity sensor may be incorporated as part of a water delivery device. A holder which aligns an optical source and sensor of the proximity sensor is disclosed.

Abstract: Energy released from energized particles is sensed. Whether the energized particles include a possible energetic material is determined based on the sensed energy. If a determination is made that the energized materials include a possible energetic material, a spectral signature of the sensed energy is determined. The spectral signature of the sensed energy is compared to one or more known spectral signatures associated with energetic materials. Whether the possible energetic material is an actual energetic material is determined based on the comparison.

Abstract: In a preferred embodiment of the invention, a high density interconnect structure is provided comprised of a dielectric structure and one or more compressible conductive member for the electrical connection of a plurality of inputs and outputs of a three-dimensional module to external circuitry using a compression frame and a flex connector. The compression frame has a surface equal to or less than the surface area of the module surface upon which it is mounted and permits a plurality of modules to be “butted” together to provide, for instance, a buttable focal plane array module comprising a mosaic of buttable focal plane arrays.

Abstract: Systems, methods and sensors detect changes in incident optical radiation. Voltage is applied across one or more active areas of a detector while the incident optical radiation illuminates the active areas. Current is sensed across one or more of the active areas, a change in the current being indicative of the changes in incident optical radiation.

Abstract: A display device in which light leakage in a monitor element portion is prevented without increasing the number of steps and cost is provided. The display device includes a monitor element for suppressing influence on a light-emitting element due to temperature change and change over time and a TFT for driving the monitor element, in which the TFT for driving the monitor element is provided so as not to overlap the monitor element. Furthermore, the display device includes a first light shielding film and a second light shielding film, in which the first light shielding film is provided so as to overlap a first electrode of the monitor element and the second light shielding film is electrically connect to the first light shielding film through a contact hole formed in an interlayer insulating film. The contact hole is formed so as to surround the outer edge of the first electrode of the monitor element.

Abstract: A multi-channel arrayed isosbestic wavelength detection system comprises an arrayed light source board, an arrayed photoelectric sensor board, and an intermediate system frame. The arrayed light source board and arrayed photoelectric sensor board are assembled at opposite sides of the intermediate system frame. In addition, the arrayed light source system has a plurality of light-emitting elements, each of which comprises two monochromatic light sources that provide main wavelength and reference wavelength respectively, and the two wavelengths are isosbestic wavelengths. The arrayed photoelectric sensor system has a plurality of photoelectric sensors, which are aligned at fixed positions in one-to-one correspondence with the light-emitting elements.

Abstract: An optical sensor that is a transistor which includes a gate electrode including a semiconductor material where the carrier concentration is 1.0×1014/cm3 to 1.0×1017/cm3, an active layer including a semiconductor layer to form a channel by carriers of the same type as the gate electrode, a source electrode, a drain electrode, and a gate insulating film, wherein intensity of irradiated light is detected by a change in a value of current flowing between the source electrode and the drain electrode when the light is irradiated onto a depletion layer formed in the gate electrode; an optical sensor array, an optical sensor driving method, and an optical sensor array driving method are provided.

Abstract: A single photon detection system and method are disclosed which have a control block for helping to monitor and optimize performance, especially at high detection rates. The system is based on photon detectors constructed with avalanche photodiodes (APD) gated in time to operate in the Geiger mode. An electrical reference frequency is generated which is subtracted from the APD output in order to better isolate the breakdown event. The resulting signal is sampled and analyzed to allow the control unit to optimize the magnitude and phase of the electrical reference frequency. The control unit may also change the gate pulse shape and phase, including by the use of a digital-to-analog converter. The gate pulse can be shifted off an input optical pulse so as to estimate dark count rate, or shifted to measure a reference input signal to estimate detection efficiency.

Abstract: A sensor device includes sensor elements two-dimensionally arranged and a sensor driving section driving the sensor elements. Each of the sensor elements includes a photoelectric conversion element generating electric charge according to an amount of received light, a charge storage section connected to one end of the photoelectric conversion element and storing electric charge generated by the photoelectric conversion element, a readout section reading either a voltage value resulted from the electric charge in the charge storage section or the stored electric charge, to output the read voltage value or the read electric charge and a reset section resetting the electric charge in the charge storage section through supplying a predetermined reset voltage to the charge storage section. The sensor driving section controls the reset section so that the predetermined reset voltage is continuously or intermittently supplied to the charge storage section over a period exceeding one horizontal scan period.

Abstract: Systems and methods for detecting and measuring light emitted from a sample and having a large dynamic range, e.g., a range of luminous intensity covering six or more orders of magnitude, that may be difficult to fully detect using a single detector with a limited detection range. Simultaneous measurements of the emitted light in two intensity ranges are performed using two detectors, e.g., one including a photomultiplier tube (PMT) and the other including a solid state detector such as a photodiode. A beam splitting element directs light emitted from a sample under investigation to both detectors simultaneously such that a portion of the light impinges on the first detector and a second portion of the light impinges on the second detector.

Abstract: An optical antenna assembly including multiple optical antenna elements, each of the optical antenna elements are arranged in a regular pattern and carried by a supporting body. The regular pattern of the plurality of optical antenna elements is nonuniform. Certain ones of the optical antenna elements are configured to respond to the one or more waves of light.

Abstract: An optoelectrical device, which may be a luminaire or a photovoltaic concentrator, has a transparent cover plate. A target with an optoelectrical transducer that produces waste heat in operation is mounted at an inside face of the transparent cover plate. A primary mirror reflects light between being concentrated on the target and passing generally collimated through the cover plate. A heat spreader is in thermal contact with the target. The heat spreader has heat conductors that thermally connect the target with the inside surface of the cover plate. The heat conductors may be arms extending radially outwards, and may be straight, zigzag, or branching. An array of targets may be mounted on a common cover plate, and their heat spreaders may be continuous from target to target.

Abstract: A technique and device for fluorescence observation with good operability, high sensitivity, acid high reliability. The device is used for fluorescence observation using evanescent light. The angle of incidence of the excitation light is adjusted so that the excitation light is always totally reflected from the surface of a substrate irrespective of the angle of the surface of the substrate. The method includes a step of shining the excitation light on the observation substrate while continuously varying the angle of the excitation light with respect to the observation substrate, a step of sensing the shone excitation light by means of optical sensors, and a step of setting the angle of total reflection according to the result of the sensing by the optical sensors. The direction in which the shone excitation light travels varies with the angle of incidence. That is, the excitation light travels as the transmitted light, the reflected light, or the surface propagating light.

Abstract: An ambient light sensor includes a first stack of at least two photodiodes, wherein a cathode of one of the at least two photodiodes is electrically connected to an anode of another of the at least two photodiodes. The ALS further includes a bias source for providing a bias voltage to the first stack, and at least one switch electrically connected to the first stack. The at least one switch is operative to periodically apply the bias voltage to and remove the bias voltage from the first diode stack.

Abstract: An output circuit includes a bias circuit that operates when a power supply voltage equal to or larger than a predetermined voltage is applied, a differential amplifier circuit that outputs signals according to input differential signals upon receiving a bias current or bias voltage generated when the bias circuit is operated, an output stage circuit that receives differential signals according to an output from the differential amplifier circuit and outputs output signals according to the differential signals, the output stage circuit having fewer number of stages of elements connected in series than the bias circuit, and a pull-down circuit that forcibly sets a level of one of the differential signals received by the output stage circuit to a ground voltage to fix the level of the output signals output from the output stage circuit when the bias current or the bias voltage generated by the bias circuit is not supplied.

Abstract: In one embodiment of the invention, a semiconductor optical amplifier (SOA) in a laser ring is chosen to provide low polarization-dependent gain (PDG) and a booster semiconductor optical amplifier, outside of the ring, is chosen to provide high polarization-dependent gain. The use of a semiconductor optical amplifier with low polarization-dependent gain nearly eliminates variations in the polarization state of the light at the output of the laser, but does not eliminate the intra-sweep variations in the polarization state at the output of the laser, which can degrade the performance of the SS-OCT system.

Abstract: A broadband receiving apparatus includes an antenna to receive a radio signal having a plurality of modulation frequencies. An amplifier drives a laser source from the broadband radio signal to produce an optical signal having a plurality of spectral components. A diffraction grating transforms the optical signal into its spectral components. An array of photo-detectors converts the spectral components into electronic signals corresponding to the plurality of modulation frequencies. A transmitting apparatus includes an array of coherent laser emitters driven by electronic signals corresponding to a plurality of modulation frequencies to produce optical signals corresponding to a plurality of spectral components. A diffraction grating inverse transforms the spectral components into a composite optical signal. A photo-detector converts the composite optical signal into a composite electronic signal including the plurality of modulation frequencies.

Abstract: Method and systems related to obstructing a first predefined portion of at least one defined wavelength of light incident upon a first photo-detector array; and detecting the at least one defined wavelength of light with a photo-detector in a second photo-detector array.

Abstract: A photosensitive chip, including: at least one set of photosensors substantially aligned in a Y direction; and a layer of non-transmissive material including a plurality of openings. Each opening in the plurality of openings includes a respective center line and overlaps only a portion of a respective photosensor so that only the portion of the respective photosensor is photosensitive. The respective center lines for openings for each set of photosensors are not collinear in the Y direction. In an example embodiment, the plurality of openings includes at least one row of openings substantially aligned in an X direction, orthogonal to the Y direction. In an example embodiment, each opening has an equal width in an X direction, orthogonal to the Y direction.

Abstract: A photodetector includes one or more first photodiode regions that are covered by an optical filter configured to reject infrared (IR) light and that produce a first current (I1). The photodetector also includes one or more second photodiode regions that are covered by a light blocking material configured to reject visible and infrared light and that produce a second current (I2). The photodetector also includes one or more third photodiode regions that are not covered by the optical filter and are not covered by the light blocking material and that produce a third current (I3). Additionally, the photodetector includes circuitry configured to produce an output indicative of the first current (I1) or a scaled version of the first current (I1), minus the second current (I2) or a scaled version of the second current (I2), minus the third current (I3) or a scaled version of the third current (I3). The optical filter configured to reject IR light can be, e.g.

Abstract: A system with applications in pattern recognition, or classification, of DNA assay samples. Because DNA reference and sample material in wells of an assay may be caused to fluoresce depending upon dye added to the material, the resulting light may be imaged onto an embodiment comprising an array of photodetectors and an adaptive neural network, with applications to DNA analysis. Other embodiments are described and claimed.

Abstract: An integrated circuit transimpedance amplifier arrangement constituted of: a plurality of internal matched resistors; a current multiplier arranged to output a signal whose value is a function of an input current signal, an external resistor and a first set of the plurality of internal matched resistors; and an output transimpedance amplifier coupled to the output of the current multiplier, the output transimpedance amplifier exhibiting a gain whose value is a function of a second set of the plurality of internal matched resistors, wherein the output of the output transimpedance amplifier is a function of the input current signal, the external resistor, the first set of the plurality of internal matched resistors and the second set of the plurality of internal matched resistors, wherein the variations with temperature of the first set of the plurality of internal matched resistors and the second set of the plurality of internal matched resistors cancel.

Abstract: An optical module transmits optical signals through a plurality of optical fibers in parallel. The optical module includes a substrate including an electrode pattern, a plurality of optical elements mounted on the electrode pattern of the substrate, and an electronic device mounted on the electrode pattern of the substrate and electrically connected to the optical elements. The optical elements and the electronic device are arranged on the substrate close to each other such that lengths of a plurality of transmission lines each transmitting a signal between each of the optical elements and the electronic device are minimized.

Abstract: Disclosed is a device for optical scanning, comprising: a plurality of photo sensors, where the photo sensors are arranged to detect light incident on the photo sensors, emitted from a light source and reflected from an object subject to optical scanning; wherein the amount of light received at least one of the photo sensors is to a larger extent light transmitted from the light source; and to a smaller extent light reflected from the object.

Abstract: The present invention relates to a measurement method to determine the magnitude and intensity of solar radiation/collected by a photovoltaic solar panel, without the need of using specific sensors for this purpose—With the present method? the power conditioning systems used in small photovoltaic panels to charge small rechargeable batteries, will now be able to provide an electrical signal, in the form of a pulse sequence or in any other electrical signal, that represents the value of the quantity that generates the available energy. The present method enables the monitoring the energy transfer between the solar panel and a rechargeable battery using a switched, voltage converter; additionally it indicates the magnitude of the solar radiation falling on the solar panel. It is based on the adaptation of a direct voltage to direct voltage boost converter circuit in.

Abstract: While high-purity hexagonal boron nitride monocrystal (hBN) obtained by way of a high temperature/high-pressure treatment in the presence of a high-purity solvent has excellent properties in terms of far-UV luminescence characteristics, it has drawbacks including that it can be easily adversely affected by mechanical vibrations and impetus, that monocrystal shows a poor morphological retentiveness and that the luminescence characteristics fluctuate to shift the selected and set wavelength. The present invention can overcome the drawbacks of being easily affected by vibrations and showing a poor morphological retentiveness by grinding down the monocrystal obtained by a solvent/refining process into powder and applying the powder to a light emitting surface. Thus, the present invention provides crystal powder to be used for a far-UV luminescence device showing excellent luminescence characteristics that are stable and do not fluctuate.

Abstract: An illumination detection system comprises an excitation radiation source and associated radiation processing arrangement, and a focusing arrangement for focusing the excitation radiation from the radiation processing arrangement onto an analysis region of a sample. A radiation collection arrangement collects radiation from the analysis region of the sample resulting from the excitation, and a detector detects the collected radiation. The focused excitation radiation comprises an excitation line which is evanescent in the sample. This combines the advantages of line scanning (reduced analysis time) and evanescent excitation (reduced background signal) and therewith enables increased measurement speed and precision for point of care application.

Abstract: A light sensing system comprises a first light sensor (21?), a second light sensor (21) and a first light shielding material (24) disposed over the first light sensor (21?) but not over the second light sensor (21) so as to block ambient light from being incident on the first light sensor (21). A first electrically conductive material (23a) is disposed between the first light shielding layer (24) and the first light sensor and a second electrically conductive material (23b) is disposed over the second light sensor. The second electrically conductive material (23b) is at least partially light-transmissive. Providing the first electrically conductive material (23a) between the first light shielding layer (24) and the first light sensor eliminates any parasitic capacitance that would otherwise be set up by the light shielding layer (24) (which is typically a metallic layer).

Abstract: The present invention relates to a photoelectronic sensor which collectively adjusts light emission intensity of plural light emitting elements and light reception sensitivity of plural light receiving elements automatically or manually. In order to collectively adjust light emission intensity of plural light emitting elements and light reception sensitivity of single light receiving elements automatically, a photoelectronic sensor of the present invention is configured such that constant current light emission signal are applied to the light emitting elements, a light amount of environment is measured by the light receiving elements and stored, a reflection light amount from a body to be measured is stored, signal intensities indicating the respective light amounts are calculated, optimal thresholds of light emission intensity and light reception sensitivity are provided automatically or manually, so that setting of sensor sensitivity is performed.

Abstract: The present invention enables the detection of light using an APD that has high gain and/or a wide range of operating temperature. A first APD is biased with a voltage bias that is controlled based on the breakdown voltage of a second APD, which is thermally coupled with the first APD. Changes in the breakdown voltage of the second APD due to aging, temperature chances, and the like, are reflective of changes in the breakdown voltage of the first APD. As a result, the first APD can be operated with greater stability and reliability at high gain and over larger temperature excursions than APDs known in the prior art.

Abstract: An optical antenna assembly including multiple optical antenna elements, each of the optical antenna elements are arranged in a regular pattern and carried by a supporting body. The regular pattern of the plurality of optical antenna elements is nonuniform. Certain ones of the optical antenna elements are configured to respond to the one or more waves of light.

Abstract: An optical antenna assembly including multiple optical antenna elements, each of the optical antenna elements are arranged in a regular pattern and carried by a supporting body. The regular pattern of the plurality of optical antenna elements is nonuniform. Certain ones of the optical antenna elements are configured to respond to the one or more waves of light.

Abstract: A pulsed-laser beam detector with improved sun and temperature compensation. The detector includes a plurality of photo detectors, an ambient temperature sensor, a sun exposure filter and a mirroring circuit, a microcontroller unit that includes pre-stored values in a database and an algorithm—decision logic, a time base circuit that feeds microcontroller, an adjustable gain amplifier, a threshold setting circuit, a peak detector circuit, a comparator circuit, and a noise cancellation circuit. The gain of the amplifier is adjustable in real time to predetermined values, and the gain depends on the measured values from the detectors, and temperature sensor, that are preprocessed if necessary, and compared with the values already stored in the microcontroller unit and subjected to the program logic stored in the microcontroller that determines the gain of the amplifier.

Abstract: While objects travel through an optical cavity, the cavity provides output light that is affected by the objects, causing the output light to have a varying intensity function. The output light is photosensed to obtain sensing results that depend on the varying intensity function. The sensing results are used to distinguish at least one object, such as from its environment or from objects of other types. The objects can, for example, be particles or biological cells, and their optical characteristics, such as refractive index or absorption, can affect the output light, so that information about them is included in the output light. The output light can, for example, have a laterally varying intensity function with peaks whose features change due to the objects. The sensing results can also be used to track objects, together with other information, such as about the speed of a fluid that carries the objects through the cavity.