Abstract: A method and apparatus for identifying individual trees and its canopy shape in LiDAR data determines if the view of each LiDAR data point is blocked by one or more neighboring LiDAR data points. LiDAR data points that do not have neighboring LiDAR data points that block the view are considered to be a central part of a tree canopy. In one embodiment, those LiDAR data points that are central part of a canopy are added to an output file that stores clusters of data points for each canopy detected. The central part of the canopy area can be analyzed to predict one or more characteristics of the tree.

Abstract: [Problem] To provide an electro-optical distance meter in which the measurement time is reduced, and a temperature phase drift of electrical components is reduced. [Solution Means] An electro-optical distance meter includes a first light-emitting element (13) which emits light modulated with a plurality of main modulation frequencies (F1 and F2), a second light-emitting element (14) which emits light modulated with a plurality of adjacent modulation frequencies (F1??f1 and F2??f2) close to the main modulation frequencies, respectively, first and second light receiving elements (40 and 48) which receive light emitted from both light-emitting elements, a first frequency converter group (42, 44) connected to the first light receiving element, and a second frequency converter group (50, 52) connected to the second light receiving element.

Abstract: A physical quantity sensor includes: a semiconductor laser which emits laser light to a measurement target; an oscillation wavelength modulating device that operates the semiconductor laser such that at least one of a first oscillation period and a second oscillation period alternately exists; a detector that detects an electrical signal including interference waveforms, the interference waveforms being caused by a self-coupling effect of the laser light and return light from the measurement target; a signal extracting device that measures each cycle of the interference waveforms whenever the interference waveform is input; a cycle correcting device that compares each cycle of the interference waveforms with a reference cycle to correct the cycles of the interference waveforms; and a calculating device that calculates at least one of displacement and velocity of the measurement target based on each of the cycles of the interference waveforms corrected by the cycle correcting device.

Abstract: An exemplary multifunction light transceiver device includes a plurality of light sources. At least one luminescent member is configured to emit visible light responsive to radiation incident on the luminescent member. A controller selectively controls the light sources to achieve multiple functions. The controller controls at least one of the light sources to irradiate the luminescent member to illuminate an area near the device. The controller controls at least one of the light sources to communicate information from the device. The controller also controls at least one of the light sources to emit light toward an object. A detector associated with the controller detects any portion of light that is reflected toward the detector. The controller uses any detected light for making a determination regarding an object from which the detected light reflected.

Abstract: A multifunction detector for detecting energy reflected from the surface, the detector comprising: a focal plane array in communication with the optical receiving path; and an optical receiving path; a read-only integrated circuit in communication with the optical receiving path, integrated with a focal plane array; and a processor programmed to operate the focal plane array and read-out integrated circuit in a first mode to process signals in a first frequency band, and in a second mode to process signals in a second, wider frequency band.

Abstract: In one aspect, a method includes forming range bins from range compressed data, the range compressed data comprising a train of coherent pulses formed based on a transmitted signal from a laser detection and ranging (LADAR) sensor and having a large time-bandwidth product and for each range bin, compensating for motion of the LADAR sensor, performing a Fourier transform on the compressed range data, determining a centroid of individual velocity measurements and performing Fourier transform of the centroid to determine a vibration.

Abstract: Range-finding apparatus comprises a source of pulsed radiation of variable repetition rate and a beam-splitter for dividing the pulsed radiation into two portions which are directed respectively to a local retro-reflector and to a retro-reflector co-located with a remote target the range of which is to be determined. The source, beam-splitter and retro-reflectors are arranged in the form of Michelson interferometer together with a detector. The repetition rate of the source is tuned to frequencies f such that round-trip distance to the remote target is mc/f where m is an integer, this condition being detected by observing a heterodyne signal at the detector. Two such frequencies enable range to be determined. The precision with which range is determined may be increased by carrying out interferometry using the two portions. The accuracy of the method does not depend on absolute range (as with triangulation) and is not limited by the speed of timing electronics, as is the case for time-of-flight techniques.

Abstract: A positioning system and method for determining a coordinate of an object may comprise a positioning transmitter system and a positioning receiver system. The positioning transmitter system includes at least four light sources and a master anchor to modulate the light sources to emit modulated light signals each having a modulation frequency. The positioning receiver system comprises a lens to focus the light signals onto an optical sensor, an envelope detector to receive a signal from the optical sensors and provide output signals corresponding to the modulation frequency, and positioning detection circuitry.

Abstract: A detection apparatus and method for FMCW LIDAR employ signals whose frequencies are modified so that low-cost and low-speed photodetector arrays, such a can be employed for range detection. The LIDAR is includes a single mode swept frequency laser (SFL), whose optical frequency is varied with time, as a result of which, a target beam reflected back by the target is shifted in frequency from a reference beam by an amount that is proportional to the relative range z to the target. The reflected target beam is combined with the reference beam and detected by the photodetector array. The difference between the frequencies of the reflected target beam and the reference beam is reduced to a level that is within the bandwidth of the photodetector array by first modulating the target and/or reference beam.

Abstract: An electro-optical distance-measuring unit (10) includes a light source (1), the emitted light of which in the distance-measuring unit (10) is guided onto a measurement path (8) at least by one polarizing beam splitter (3), an electro-optical modulator (5) and a retarder (6). Light that is returned along the measurement path (8) is guided at least by the retarder (6), the electro-optical modulator (5) and the polarizing beam splitter (3) onto a detector (4). The distance-measuring unit (10) furthermore includes a control and evaluation unit (11) for determining a length of the measurement path (8) in accordance with a modulation frequency of the electro-optical modulator (5) and a signal of the detector (4). The light source (1) has a broad spectrum of the emitted light and is preferably a super-luminescent diode.

Abstract: A positioning system and method for determining a coordinate of an object may comprise a positioning transmitter system and a positioning receiver system. The positioning transmitter system includes at least four light sources and a master anchor to modulate the light sources to emit modulated light signals each having a modulation frequency. The positioning receiver system comprises a lens to focus the light signals onto an optical sensor, an envelope detector to receive a signal from the optical sensors and provide output signals corresponding to the modulation frequency, and positioning detection circuitry.

Abstract: A vehicle position measurement system (100) and method to determine the (relative) position of a vehicle (110) and an object (120) are proposed. The system comprises at least two light sources (131, 132) capable of emitting light and positioned at a predetermined distance (140) to each other. Furthermore the system comprises at least one detector (150/151, 152) capable of measuring the light emitted. The light emitted by the light sources comprises synchronized light source identification codes. The detector is arranged to determine the position of the vehicle (110) and object (120) on the basis of a phase-difference measurement between the light originating from the individual light sources (131, 132) and a comparison phase. The vehicle (110) may comprise the at least two light sources (131, 132) and the detector (151, 152), while the phase-difference is measured between light reflected from the object (120) and the comparison phase.

Abstract: An optical system of a shape measuring instrument includes a laser diode, a first optical system irradiating an object to be measured with laser beam, a second optical system focusing reflected light from the object to be measured, and a CCD line sensor portion for detecting a laser beam from the second optical system, where the first optical system includes an optical path displacing unit for displacing an optical path for laser beam, the optical path displacing unit includes a glass plate rotating about a rotating axis extending in a direction perpendicular to a displacement plane of the optical path, a rotating unit for the glass plate, and a rotating unit controller, and the rotating unit controller causes a rotation angle of the rotating unit to coincide with a rotation angle of the rotating unit obtained when the maximum value of an amount of light received by the CCD line sensor according to rotation of the rotating unit is measured by the rotating unit controller.

Abstract: A beam irradiation device includes a photodetector which receives servo light; a signal processing section which generates a position detection signal based on a detection signal from the photodetector; and a control section which controls the laser light source and the actuator for beam scanning based on the position detection signal. The signal processing section performs a sampling operation with respect to the detection signal from the photodetector at two consecutive sampling timings. The signal processing section includes an A/D converting section which converts a difference between two sampling values obtained by the sampling operation into a digital signal, and a computing section which computes the position detection signal based on the digital signal from the A/D converting section.

Abstract: A unit pixel included in a photo-detection device, the unit pixel including a floating diffusion region in a semiconductor substrate, a ring-shaped collection gate over the semiconductor substrate, a ring-shaped drain gate over the semiconductor substrate, and a drain region in the semiconductor substrate, wherein the collection gate and the drain gate are respectively arranged between the floating diffusion region and the drain region.

Abstract: A distance measuring device measures a distance from a phase difference of beaten down processing signals even when fluctuations occur in a frequency of an oscillator. The distance measuring device includes a laser unit, a dividing device, a reference light receiving unit, and a measuring light receiving unit. The distance measuring device further includes an oscillator, a first mixer, a second mixer, a fourth filter, a fifth filter, a third mixer, a sixth filter, a second filter, a phase difference measuring unit, and a distance measuring unit. The phase difference measuring unit measures a phase difference of the two beat signals extracted by the sixth filter and the second filter. The distance measuring unit measures a distance based on the phase difference measured by the phase difference measuring unit.

Abstract: [Problem] To provide an electro-optical distance meter in which the measurement time is reduced, and a temperature phase drift of electrical components is reduced. [Solution Means] An electro-optical distance meter includes a first light-emitting element (13) which emits light modulated with a plurality of main modulation frequencies (F1 and F2), a second light-emitting element (14) which emits light modulated with a plurality of adjacent modulation frequencies (F1??f1 and F2??f2) close to the main modulation frequencies, respectively, first and second light receiving elements (40 and 48) which receive light emitted from both light-emitting elements, a first frequency converter group (42, 44) connected to the first light receiving element, and a second frequency converter group (50, 52) connected to the second light receiving element.

Abstract: A continuous wave Light Detection and Ranging (CW LiDAR) system utilizes two or more laser frequencies and time or range shifted pseudorandom noise (PN) codes to discriminate between the laser frequencies. The performance of these codes can be improved by subtracting out the bias before processing. The CW LiDAR system may be mounted to an artificial satellite orbiting the earth, and the relative strength of the return signal for each frequency can be utilized to determine the concentration of selected gases or other substances in the atmosphere.

Abstract: A compact LADAR transmitting and receiving apparatus includes a pulse laser generating pulses of light; a transmitter collimating and directing the pulses of light toward a target; a receiver collecting reflected pulses of light, the reflected pulses of light having been reflected from the target, the receiver comprising a tapered fiber bundle; a sensor operatively connected to the tapered fiber bundle, where the sensor comprises a photosensitive region and outputs a photocurrent; an amplifier amplifying the photocurrent; and a power divider splitting the amplified photocurrent between a high gain channel and a low gain channel; a RF interface accepting the high gain channel, the low gain channel, and an undelayed sample of a pulse of light generated from the pulse laser as input; a processing unit accepting output from the RF interface; and a display unit displaying output from the processing unit.

Abstract: A physical quantity sensor includes: a semiconductor laser which emits laser light to a measurement target; an oscillation wavelength modulating device that operates the semiconductor laser such that at least one of a first oscillation period and a second oscillation period alternately exists; a detector that detects an electrical signal including interference waveforms, the interference waveforms being caused by a self-coupling effect of the laser light and return light from the measurement target; a signal extracting device that measures each cycle of the interference waveforms whenever the interference waveform is input; a cycle correcting device that compares each cycle of the interference waveforms with a reference cycle to correct the cycles of the interference waveforms; and a calculating device that calculates at least one of displacement and velocity of the measurement target based on each of the cycles of the interference waveforms corrected by the cycle correcting device.

Abstract: A system and method for determining a measured distance between a measuring device (20A) and an object (21), the system including a first laser source (13) for producing a first light beam (13A) having a first waveform (32) and a first frequency; a second laser source (11) for producing a second light beam (1 IA) having a second frequency, said second light beam (HA) having a second waveform (36), wherein said first frequency is chirped up at the first rate as said second frequency is chirped down at the first rate, and said second frequency is chirped up at the second rate as said first frequency is chirped down at the first rate; an optical element (15) for combining said first light beam (13A) with said second light beam (HA) into a combined light beam path (17), said optical element (15) splitting a returning portion of said combined light beam path (17) into a third light beam (24); and a single detector (23) for receiving said third light beam (24) including two different beat frequencies that are propo

Abstract: A method for frequency modulated continuous wave LADAR imaging is provided. The method comprises the steps of generating a chirped laser signal and a constant-frequency laser signal, forming a target laser signal from the chirped laser signal and the constant-frequency laser signal and forming a local oscillator laser signal from the chirped laser signal and the constant-frequency laser signal. The method further comprises delaying or frequency shifting the local oscillator laser signal and directing the target laser signal to a target. The method further comprises combining a returned signal received from the target with the delayed or frequency shifted local oscillator laser signal to form a combined received signal, and capturing the combined received signal with a plurality of image sensors.

Abstract: A measuring device , e.g., a measuring device for a motor vehicle, is for measuring a distance between the measuring device and at least one object and/or measuring a difference in speed between the measuring device and the at least one object. The measuring device includes an emitting apparatus for transmitting a transmission signal encompassing at least two sequences of signal portions, a first sequence of signal portions and a second sequence of signal portions with two respective temporally alternating signal portions. The frequency of at least two signal portions of a sequence of signal portions differs by one respective difference frequency, the difference frequency of the first sequence of signal portions being different from the difference frequency of the second sequence of signal portions.

Abstract: A compact LADAR transmitting and receiving apparatus includes a pulse laser generating pulses of light; a transmitter collimating and directing the pulses of light toward a target; a receiver collecting reflected pulses of light, the reflected pulses of light having been reflected from the target, the receiver comprising a tapered fiber bundle; a sensor operatively connected to the tapered fiber bundle, where the sensor comprises a photosensitive region and outputs a photocurrent; an amplifier amplifying the photocurrent; and a power divider splitting the amplified photocurrent between a high gain channel and a low gain channel; a RF interface accepting the high gain channel, the low gain channel, and an undelayed sample of a pulse of light generated from the pulse laser as input; a processing unit accepting output from the RF interface; and a display unit displaying output from the processing unit.

Abstract: A device for measuring movement of an object (15) and the device relative to each other. The device comprises a laser (3) for generating a measuring beam (13), which is converged by a lens (10) in an action plane. Radiation reflected by the object (15) is converged to re-enter the laser cavity to generate a self-mixing effect in the laser (3). Measuring means (4) are provided to receive the reflected measuring beam radiation and enable the frequency difference between the measuring beam (13) and the reflected measuring beam radiation to be determined, which is representative of the relative movement.

Abstract: A device for optoelectronic distance measurement includes an emitter having a first end for emitting a measuring beam to an object to be measured and a second end, a receiver for receiving the measuring beam reflected or dispersed back from the object to be measured and for converting it to a measurement signal, a signal processing device for filtering the measurement signal and a reference signal, and a control and analysis device for analyzing the information of the measurement signal and the reference signal so as to determine the distance from the object to be measured. The second end of the emitter is used to emit a reference beam which is received by the receiver and converted to form the reference signal.

Abstract: A laser measuring device maintains high responsivity irrespective of changes in surrounding environment, provides more correct measurement and long distance measurement due to reduced noise, and ensures the safety and reliability of a product. A first light emitter emits first wavelength light having a first wavelength. A second light emitter emits second wavelength light having a second wavelength, the second light emitter being arranged perpendicular to the first light emitter. An optical mirror allows one of the first wavelength light and the second wavelength light to pass but reflecting the other one. A first band pass filter for allows the first wavelength light to pass. A second band pass filter allows the second wavelength light to pass. A light receiver receives incident light, which arrives through one of the first and second band pass filters. A controller activates at least one of the first and second light emitters.

Abstract: An electro-optical distance-measuring unit (10) includes a light source (1), the emitted light of which in the distance-measuring unit (10) is guided onto a measurement path (8) at least by one polarizing beam splitter (3), an electro-optical modulator (5) and a retarder (6). Light that is returned along the measurement path (8) is guided at least by the retarder (6), the electro-optical modulator (5) and the polarizing beam splitter (3) onto a detector (4). The distance-measuring unit (10) furthermore includes a control and evaluation unit (11) for determining a length of the measurement path (8) in accordance with a modulation frequency of the electro-optical modulator (5) and a signal of the detector (4). The light source (1) has a broad spectrum of the emitted light and is preferably a super-luminescent diode.

Abstract: Land-based vehicle including an arrangement for monitoring objects in or about a vehicle includes a source from which modulated illumination is emitted into an area in or about the vehicle, a receiver arranged to receive illumination reflected from an object in the path of the modulated illumination, and circuitry coupled to the receiver and the source and arranged to compare a phase of the modulated illumination with a phase of the reflected radiation at a common frequency to determine whether there is a phase difference between the modulated illumination and the reflected illumination. The phase difference is a measure of a property of the object, such as the distance between the object and the source/receiver, which can be co-located. Otherwise, if the source and receiver and not co-located or substantially co-located, the distance is a measure of the distance of travel of the illumination.

Abstract: A vehicle position measurement system (100) and method to determine the (relative) position of a vehicle (110) and an object (120) are proposed. The system comprises at least two light sources (131, 132) capable of emitting light and positioned at a predetermined distance (140) to each other. Furthermore the system comprises at least one detector (150/151, 152) capable of measuring the light emitted. The light emitted by the light sources comprises synchronized light source identification codes. The detector is arranged to determine the position of the vehicle (110) and object (120) on the basis of a phase-difference measurement between the light originating from the individual light sources (131, 132) and a comparison phase. The vehicle (110) may comprise the at least two light sources (131, 132) and the detector (151, 152), while the phase-difference is measured between light reflected from the object (120) and the comparison phase.

Abstract: An optical system of a shape measuring instrument includes a laser diode, a first optical system irradiating an object to be measured with laser beam, a second optical system focusing reflected light from the object to be measured, and a CCD line sensor portion for detecting a laser beam from the second optical system, where the first optical system includes an optical path displacing unit for displacing an optical path for laser beam, the optical path displacing unit includes a glass plate rotating about a rotating axis extending in a direction perpendicular to a displacement plane of the optical path, a rotating unit for the glass plate, and a rotating unit controller, and the rotating unit controller causes a rotation angle of the rotating unit to coincide with a rotation angle of the rotating unit obtained when the maximum value of an amount of light received by the CCD line sensor according to rotation of the rotating unit is measured by the rotating unit controller.

Abstract: Range-finding apparatus comprises a source of pulsed radiation of variable repetition rate and a beam-splitter for dividing the pulsed radiation into two portions which are directed respectively to a local retro-reflector and to a retro-reflector co-located with a remote target the range of which is to be determined. The source, beam-splitter and retro-reflectors are arranged in the form of Michelson interferometer together with a detector. The repetition rate of the source is tuned to frequencies f such that round-trip distance to the remote target is mc/f where m is an integer, this condition being detected by observing a heterodyne signal at the detector. Two such frequencies enable range to be determined. The precision with which range is determined may be increased by carrying out interferometry using the two portions. The accuracy of the method does not depend on absolute range (as with triangulation) and is not limited by the speed of timing electronics, as is the case for time-of-flight techniques.

Abstract: Systems and methods for generating an optimized terrain database identify several regions, including test regions that are established from the identified regions. A first set of terrain data is received for a first test region. The first set of terrain data is compared to a second set of terrain data to determine a set of quality attributes. The quality attributes are used to determine a safety margin for the first test region. The safety margin is applied to other regions having the same or similar characteristics to the first test region. Safety margins are either generated for or applied to all other regions. All regions are then compiled into an area-wide terrain database, up to and including a worldwide database.

Abstract: Problems The present invention relates to a distance measuring device that measures the distance between a single signal transmitting means and a single signal receiving means with high accuracy by the signal transmitting means transmitting radio frequency signals. Means for Solving the Problems A distance measuring device is comprised of a signal transmitting means (101), a signal receiving means (102) and a signal processing means (103). The signal transmitting means transmits radio frequency signals, the components of which are a plurality of measuring signals in synchronization with an output reference signal of a reference oscillator (7).

Abstract: This invention relates to a method for determining the position of an object in a structure. The object receives modulated light waves from a plurality of light sources, which are arranged in the structure. The modulation is individually coded, and the position of the light sources in the structure is known. The modulation signals are synchronized, and thereby it is possible to determine the position of the object on basis of measuring the phase difference between the phase of each received modulated light wave and a comparison phase. The phase difference is used for distance calculations, which in turn give the position of the object.

Abstract: An optical homodyne detection scheme for FM chirped lidar is described. The system performs de-chirping within a photodetector, and it does not require high-speed photo-detection or RF mixing. Embodiments are also described for dealing with phase noise.

Abstract: A device (100) and method (300) for enhancing range detection accuracy in ultrasonic touchless sensing applications can include transmitting (302) an ultrasonic signal intended to reflect off a finger and produce an echo, receiving (304) the echo, saving (306) most recent echoes to a history (400), selectively discarding (308) echoes less recently saved in the history to produce a sparse history, identifying (310) a relative phase of the echo with respect to a previously received echo in the sparse history, tracking (312) a location and a movement of the finger from an arrival time of the echo and the relative phase, and providing (314) touchless control to a user interface control in accordance with the location and the movement of the finger.

Abstract: A hand-held pulse laser distance measuring device and a pulse reflection mixing method both having an algorithm which controls a microcontroller and which serves to calculate the distance to a measurement object by at least two different time differences ?11, ?12 between a measurement pulse and a reference pulse with a pulse width ?t, which time differences ?11, ?12 are measured with a pulse repetition frequency f1, f2, respectively, wherein a selection module is provided which selects at least the first pulse repetition frequency f1 from at least a first frequency set {f}1 with at least one other pulse repetition frequency f1i in such a way that the condition |?11·f1i|>A >2·|?t11·f1i| is satisfied with a pre-selected lower limit A, a relative time difference |?1i·f1i| and a relative pulse width |?t?·f1i|.

Abstract: The invention relates to an electro-optical distance measuring method wherein frequency-modulated optical radiation is emitted onto at least one target to be measured. Once the radiation back-scattered to the target is received, the chirp of radiation is modeled by means of a phase function ?(t) having parameters cj, thereby making description of the deviation of the chirp from the linear profile possible. The parameters used for description are at least partially determined from measurements or are coestimated during numerical signal processing.

Abstract: A multifunction detector for detecting energy reflected from the surface, the detector comprising: a focal plane array in communication with the optical receiving path; and an optical receiving path; a read-only integrated circuit in communication with the optical receiving path, integrated with a focal plane array; and a processor programmed to operate the focal plane array and read-out integrated circuit in a first mode to process signals in a first frequency band, and in a second mode to process signals in a second, wider frequency band.

Abstract: The disclosed subject matter relates to a method and distance measurement apparatus for measuring a distance to an object, which can include a light source, a solid state camera, a controller and a distance data generator. The light source can be configured to emit a modulated light towards an object, and the solid state camera can convert the light reflected from the object into charges. The distance data generator can be configured to calculate the distance based on the charges, and the controller can be configured to adjust the modulated light to be more favorable under various circumstances. Thus, the method of the disclosed subject matter can accurately measure distance under various circumstances and can result in providing a distance measurement apparatus with a simple configuration and at low cost, and can be used as a sensor for distance measurement of an obstacle and the like in a vehicle, security system, robot, etc.

Abstract: A device for measuring movement of an object (15) and the device relative to each other. The device comprises a laser (3) for generating a measuring beam (13), which is converged by a lens (10) in an action plane. Radiation reflected by the object (15) is converged to re-enter the laser cavity to generate a self-mixing effect in the laser (3). Measuring means (4) are provided to receive the reflected measuring beam radiation and enable the frequency difference between the measuring beam (13) and the reflected measuring beam radiation to be determined, which is representative of the relative movement.

Abstract: According to the invention, high precision distance measurement may be carried out by the broadcast of pulsed electromagnetic radiation (ES) with at least two pulse repetition frequencies, whereby the pulse repetition frequencies are selected such that the corresponding pulse separations do not have a common multiple in the range of the order of magnitude of a maximum external measurement range. The radiation is hence transmitted both to a target for measurement over the measurement path outside the device and also over a reference path inside the device, whereby the radiation (IS) passing along the reference path defines at least one start pulse and the radiation (ES) passing along the measurement path defines at least one stop pulse.

Abstract: The invention relates to an electro-optical distance measuring method wherein frequency-modulated optical radiation is emitted onto at least one target to be measured. Once the radiation back-scattered to the target is received, the chirp of radiation is modeled by means of a phase function ?(t) having parameters cj, thereby making description of the deviation of the chirp from the linear profile possible. The parameters used for description are at least partially determined from measurements or are coestimated during numerical signal processing.

Abstract: A range image generating apparatus capable of preventing or reducing generation of range images with interference which contain e.g., pixels with erroneous distance values is provided. The range image generating apparatus includes: a light source radiating a light; an image pickup element; a range image generating unit; a frequency changing unit that changes a modulation frequency for each frame rate or charge storage time; and a control unit that controls the light source and the image pickup element in synchronization with the modulation frequency changed by the frequency changing unit.

Abstract: A laser measuring device maintains high responsivity irrespective of changes in surrounding environment, provides more correct measurement and long distance measurement due to reduced noise, and ensures the safety and reliability of a product. A first light emitter emits first wavelength light having a first wavelength. A second light emitter emits second wavelength light having a second wavelength, the second light emitter being arranged perpendicular to the first light emitter. An optical mirror allows one of the first wavelength light and the second wavelength light to pass but reflecting the other one. A first band pass filter for allows the first wavelength light to pass. A second band pass filter allows the second wavelength light to pass. A light receiver receives incident light, which arrives through one of the first and second band pass filters. A controller activates at least one of the first and second light emitters.

Abstract: The present invention relates to a frequency shifter in an optical path containing a continuous laser source, and it comprises at least two frequency shift modules placed in parallel and each containing an optical propagation medium, the optical path length of which is modified according to the desired frequency shift, each of these modules being controlled separately, this shifter comprising a switch (14) which is connected to the outputs of these modules and is controlled so as to choose, at each instant, the module providing the desired frequency shift, the switch delivering, at its output, a continuous optical beam whose frequency is adjusted by contiguous sections.

Abstract: Ladar systems are provided. An exemplary ladar system includes a waveform generator for generating an arbitrary waveform, a laser for transmitting a modulated light signal toward a target, and a Doppler tracking loop for tracking the Doppler frequency shift between the transmitted light signal and a received reflected light signal.

Abstract: An imaging method and apparatus using an unmodulated pulsed laser with a chirp modulated receiver is provided for producing 3D plus intensity imagery of targets in heavily cluttered locations The apparatus includes a laser for emitting a laser beam and synchronizing a receiver to receive a reflected laser signal and transform the reflected laser signal into a displayable image that includes intensity information.

Abstract: Ladar systems and methods are provided. One embodiment is a ladar system comprising: a chirp generator for generating a chirped waveform; a laser for transmitting a light signal toward a target, the light signal being modulated by the chirped waveform; and a photon-counting sensor for receiving a temporally-modulated photon stream corresponding to the modulated light signal being reflected from the target and toward the ladar system, the photon-counting sensor gated relative to the chirped waveform.