Abstract: An amplification fiber which can generate a laser beam in a visible region even when a silica glass is used as a base material of a core of the amplification fiber is realized. An amplification fiber according to an embodiment of the present disclosure includes a core configured to generate a laser beam from an excitation beam in a visible region, and a cladding surrounding the core. The core is composed of a core material including Dy, one or more elements selected from Al, Ge, and P, and a silica glass.

Abstract: A lidar sensor comprising a laser, an optical sensor, and a processor. The lidar sensor can determine a distance to one or more objects. The lidar sensor can optionally embed a code in beams transmitted into the environment such that those beams can be individually identified when their corresponding reflection is received.

Abstract: The present disclosure discloses a laser radar for meteorological observation, and specifically relates to the field of meteorology. The laser radar comprises a base. According to the present disclosure, air pressure at the bottom of 301 is increased by injecting gas into the interior of 202, so that the 301 falls off from 201, and the disassembly between the stable seat and the connecting sleeve plates is realized; with regard to the disassembly process of the connecting sleeve plates and the base, the magnetic pole of a positioning electromagnet is changed mainly by switching the current direction of an external coil of the positioning electromagnet, so that the positioning electromagnet is separated from the locking magnet, thereby facilitating the detachment of the base and the connecting sleeve plates in combination with the linkage component, and the disassembly process of the whole device.

Abstract: An apparatus includes: a gas maintenance system having a gas supply system fluidly connected to one or more gas discharge chambers; a detection apparatus fluidly connected to each gas discharge chamber; and a control system connected to the gas maintenance system and the detection apparatus. The detection apparatus includes: a vessel defining a reaction cavity that houses a metal oxide and is fluidly connected to the gas discharge chamber for receiving mixed gas including fluorine from the gas discharge chamber in the reaction cavity, the vessel enabling a reaction between the fluorine of the received mixed gas and the metal oxide to form a new gas mixture including oxygen; and an oxygen sensor fluidly connected to the new gas mixture to sense an amount of oxygen within the new gas mixture. The control system is configured to estimate a concentration of fluorine in the received mixed gas.

Abstract: A target measurement device is provided. The target measurement device includes a fixing ring, a main body, and a transceiver. The fixing ring has a first surface. The main body is over the first surface of the fixing ring. The transceiver is coupled to the main body. The transceiver is at least movable between a center of the fixing ring to an edge of the fixing ring from a top view perspective. A method for measuring a target is also provided.

Abstract: A modular LIDAR system comprising a seed laser configured to output a beam, a modular modulator coupled to receive the beam output the seed laser and modulate the beam to create a modulated beam, a modular amplifier coupled to receive the modulated beam from the modular modulator and generate an amplified beam, and a modular transceiver chip coupled to the modular modulator and the modular amplifier, the transceiver chip configured to emit the beam perpendicularly from a first surface of the transceiver chip through an optical window; and receive a reflected beam from a target through the optical window.

Abstract: An optical apparatus includes: a substrate having a first material; an absorption region having a second material different from the first material, the absorption region configured to absorb photons and to generate photo-carriers including electrons and holes in response to the absorbed photons; a first well region surrounding the absorption region and arranged between the absorption region and the substrate, the first well region being doped with a first polarity; and one or more switches each controlled by a respective control signal, the one or more switches each configured to collect at least a portion of the photo-carriers based on the respective control signal and to provide the portion of the photo-carriers to a respective readout circuit.

Abstract: A method of determining solar radiation exposure at a predetermined location is provided. The method may include generating a first two-dimensional (2D) matrix including a plurality of elements, wherein each element of the plurality of elements of the first 2D matrix includes an elevation/azimuth pair representing a light ray extending from the predetermined location to one or more positions in the sky. The method may further include generating a second 2D matrix including a plurality of elements, wherein each index of the second 2D matrix includes an associated elevation/azimuth pair of the first 2D matrix. Each element of the plurality of elements of the second 2D matrix represents an amount of solar radiation to impinge on the predetermined location from a direction of a respective elevation/azimuth pair.

Abstract: A light sensing system includes a plurality of light-emitting devices arranged to have a first optical axis and a plurality of light-receiving devices arranged to have a second optical axis, the second optical axis being parallel with the first optical axis. The plurality of light-emitting devices and the plurality of light-receiving devices are formed to have a monolithically integrated structure, and the first optical axis and the second optical axis are substantially coaxial to each other, thus improving the efficiency of light reception.

Abstract: The present disclosure relates to a method and a system for laser distance measurement. The method includes: obtaining, from a control circuit, a synchronization signal; generating, by at least one signal generator, a first periodic signal, a second periodic signal, and a third periodic signal based on the synchronization signal; emitting, by a laser emitting device, a laser beam toward a target, the laser beam being generated under a modulation of the first periodic signal; generating, by an optical detector, a measurement signal in response to a signal mixing of the second periodic signal and a reflected laser beam from the target; and determining a distance to the target based on the measurement signal and the third periodic signal.

Abstract: A ranging system includes: a source generating a wideband incident wave that is transmitted toward a target and that is reflected by the target to form a reflected wave; a feedback detector to detect the reflected wave to generate a detected signal; an operator configured to perform low-pass filtering on the detected signal at an adjustable filtering bandwidth to generate a filtered signal, and calculate cross-correlation of a feedback signal that originates from the filtered signal and a reference signal that corresponds to the incident wave to generate a cross-correlation result; and a controller calculating a distance to the target based on an operation output that originates from the cross-correlation result.

Abstract: Methods and laser systems are disclosed for generating amplified output laser pulses with individually specified pulse energies and/or pulse shapes at individually specified time points at an output by providing a first pulse sequence of input laser pulses with a same pulse energy and a same temporal pulse distance smaller than a temporal pulse distance between adjacent output laser pulses, selecting input laser pulses arriving at the output at or close to the specified time points to form a second pulse sequence of input laser pulses, coupling at least one sacrificial laser pulse (energy balance or temporal balance) into the second pulse sequence, amplifying the second pulse sequence of input laser pulses with the sacrificial laser pulse, and coupling out the amplified sacrificial laser pulse from the amplified second pulse sequence upstream of the output to obtain the amplified output laser pulses.

Abstract: A LIDAR sensor assembly includes a laser light source to emit laser light, and a light sensor to produce a light signal in response to sensing reflections of the laser light emitted by the laser light source from a reference surface that is fixed in relation to the LIDAR sensor assembly. A controller of the LIDAR sensor assembly can process a plurality of samples of reflected light signals, process the samples to remove erroneous readings, and then provide accurate distance measurement. The system can use low-pass filters, or other components, to filter the plurality of samples to enable the “actual,” or primary, reflected light signal (i.e., light signal reflected off of a surface in an environment external to the sensor assembly, as opposed to extraneous, internal reflections off of lenses or other components or noise) to be identified and an accurate time of flight to be calculated.

Abstract: A light detection and ranging (LiDAR) sensor is described herein. The LiDAR sensor can comprise a fiber optic ending, a laser assembly, and one or more processors. The fiber optic ending can comprise a fiber optic cable terminated by a reflector. The laser assembly can emit a chirp signal to detect an object in an environment. A portion of the chirp signal can be diverted to the fiber optic ending. The one or more processors construct a profile of the chirp signal based on the diverted portion of the chirp signal. The one or more processors determine a best fit curve based on the profile of the chirp signal and one or more parameters associated with the best fit curve. A frequency offset between an emitted chirp signal and a returned chirp signal can be computed based on the best fit curve and the one or more parameters. Based on the frequency offset, the one or more processors can determine a range of the object.

Abstract: Provided are a light emitting module, a optical signal detection unit, an optical system and a laser radar system. The light emitting module comprises: a high-frequency modulation signal output unit (10), which is configured to output at least two preset high-frequency modulation signals with different frequencies; a laser emitting unit (20), which is connected with the high-frequency modulation signal output unit (10), and is configured to emit at least two laser beams with different frequencies after being respectively modulated by at least two high-frequency modulation signals with different frequencies; a reference signal emitting unit (30), which is connected with the high-frequency modulation signal output unit (10), and is configured to emit at least two reference signals with different frequencies after being respectively modulated by at least two high-frequency modulation signals with different frequencies.

Abstract: An electromagnetic wave detection apparatus (10) includes a separation unit (16), a first detector (17), a switch (18), and a second detector (20). The separation unit (16) separates incident electromagnetic waves so that the electromagnetic waves propagate in a first direction (d1) and a second direction (d2). The first detector (17) detects the electromagnetic waves that propagate in the first direction (d1). The switch (18) includes a plurality of switching elements (se). The switching elements (se) are capable of switching the propagation direction of the electromagnetic waves that propagate in the second direction (d2) to a third direction (d3) and a fourth direction (d4). The second detector (20) detects the electromagnetic waves that propagate in the third direction (d3).

Abstract: Methods and systems for in-service inspection of freight car axles are provided. A camber angle of a wheel attached to a target axle is measured at one or more points in a revolution of the wheel. A determination of whether a defect is present in the target axle is made based on the measured camber angle at the one or more points in the revolution of the wheel. A determination that a defect is present in the target axle is made when a camber angle of the wheel at one or more points in the revolution of the wheel exceeds a threshold, and/or a determination that a defect is not present is made when no camber angle of the wheel at any point in the revolution of the wheel exceeds the predetermined threshold. An alert is generated in response to determining that a defect is present.

Abstract: In N-phase correlations vector synthesis time-of-flight (ToF) ranging employing N correlators, the correlation time at each signal cycle is reduced to mitigate pixel saturation by sun light or strong reflected light as well as to minimize the influence of external noise. Typically, the correlation time, during which the received signal is correlated with the transmitting signal, is set to be one full cycle in each transmitting signal period. In this invention, reducing the correlation time to 1 N , 1 2 ? N , or ? 1 k ? N of a full cycle period in each transmitting signal period is disclosed, where k is a real number greater than 1, but k is not 2. Depending on the intensity of the ambient light, the correlation time is flexibly and optimally selected. Multiple fractional correlations produced by a reduced correlation time are integrated over multiple signal periods to obtain more reliable signals of the correlation vectors.

Abstract: A laser system having a multi-pass amplifier system which includes at least one seed source configured to output at least one seed signal having a seed signal wavelength, at least one pump source configured to output at least one pump signal, at least one multi-pass amplifier system in communication with the seed source and having at least one gain media, a first mirror, and at least a second mirror therein, the gain media device positioned between the first mirror and second mirror and configured to output at least one amplifier output signal having an output wavelength range, the first mirror and second mirror may be configured to reflect the amplifier output signal within the output wavelength range, and at least one optical system may be in communication with the amplifier system and configured to receive the amplifier output signal and output an output signal within the output wavelength range.

Abstract: Provided is a surveying instrument configured so that the optical axis of a guide light irradiation unit that irradiates guide light for guiding a survey operator and the optical axis of a lens barrel portion of a distance-measuring optical system become parallel to each other on a horizontal plane. The guide light irradiation unit is not disposed above the lens barrel portion that substantially matches a collimation direction is horizontally shifted with respect to the lens barrel portion. The horizontal shift distance D is configured so that a horizontal distance D between the optical axis of guide light and the optical axis of the lens barrel portion satisfies tan(?/2)×Cmin>D provided that ? is an irradiation angle of the guide light in the horizontal direction, and Cmin is a shortest use distance of the surveying instrument.