Abstract: An optoelectronic sensor (10) having a light transmitter (12) for the transmitting of laser pulses (18) into a monitored region (24) by means of a laser light source (14) and having a driver circuit (16, 30) for the laser light source (14) is described which is designed to set the light transmitter (12) into a working state in which the laser light source (14) transmits a laser pulse (18) or into a preparatory state. The driver circuit (16, 30) is further designed to set the light transmitter (12) into the preparatory state in each case prior to the transmission of a laser pulse (18).

Abstract: In one embodiment, a three dimensional imaging system includes a portable housing configured to be carried by a user, microelectrical mechanical system (MEMS) projector supported by the housing sensor supported by the housing and configured to detect signals emitted by the MEMS projector, a memory including program instructions for generating an encoded signal with the MEMS projector, emitting the encoded signal, detecting the emitted signal after the emitted signal is reflected by a body, associating the detected signal with the emitted signal, comparing the detected signal with the associated emitted signal, determining an x-axis dimension, a y-axis dimension, and a z-axis dimension of the body based upon the comparison, and storing the determined x-axis dimension, y-axis dimension, and z-axis dimension of the body, and a processor operably connected to the memory, to the sensor, and to the MEMS projector for executing the program instructions.

Abstract: A system and method for measuring photons utilizing a low-power light source modulated with a code sequence to interrogate a sample of interest. Preferably a portion of the scattered light from the sample is detected by a photo-detector. A correlation of the photo-detector signal and the code sequence produces an estimate of the distribution of flight times for photons traveling from the source to the detector.

Abstract: The invention relates to a device (1) projecting a reference line, having an electro-optical distance measurement unit that guides an optical reference beam (RS) along a defined reference path (RP), wherein at least one part of the reference path (RP) may be detected upon passing through by the human eye and/or detectors as a reference line. In conjunction with passing through the reference path (RP), a distance measurement occurs to at least one point (Pi) on the reference path (RP), particularly to a plurality of points (Pi), by transmitting a measurement beam that is parallel or coaxial to the reference beam (RS) or using the reference beam (RS) as a measurement beam.

Abstract: A position measuring system, comprising a distance measuring unit for projecting and scanning a pulsed beam for measurement to a measurement area and for measuring a distance based on a reflected light of the pulsed beam for measurement and for obtaining a position data group in the measurement area, a digital image pickup unit for acquiring an image data by taking an image of the measurement area, a storage unit for storing at least two sets of the position data groups and the image data acquired from at least two directions by interrelating and associating the position data groups with the image data, and an arithmetic unit for synthesizing the at least two position data groups through matching of the two images based on the two stored image data.

Abstract: A device (1) for the determination of distance by means of light pulses is disclosed. The device (1) comprises a light source (2) for emitting light pulses with a specified frequency, a detector (8) for receiving the light pulses emitted and reflected by the light source, and a controller (4) which is in communication with the light source (2) and the detector (8) and which can control said light source and detector by means of signals. The device (1) further comprises at least two timers (Z1, Z2, Z3) which are connected to the controller (4) and the detector (8). Said controller (4) is designed in such a way that when a light pulse is emitted by the light source (2), the controller (4) generates a start signal which triggers the time measurement by each one of the at least two timers, in order, and beginning again from the start.

Abstract: A centroiding method is provided for an optical tracking system including a laser used for countermeasuring purposes in which a pencil thin laser beam is accurately positioned onto a target through the use of centroiding techniques for ascertaining the position not only of the target but also the laser beam, with the centroiding techniques resulting in a sub-pixel level resolution. The sub-pixel resolution permits utilization of smaller cost-effective focal plane arrays by giving the small focal plane array a resolution associated with much larger focal plane arrays.

Abstract: The present invention discloses a distance detecting sensor, comprising: a casing, focusing lenses, a circuit board mounted with several electronic elements, and an emitting device emitting infrared light and a receiving device receiving and sensing a reflected infrared light. Wherein, the casing comprises a main body and two round openings on the top surface of the main body. The lenses comprise an emitting lens and a receiving lens arranged at the openings of the casing. The circuit board is mounted in the main body of the casing; the emitting device is an infrared emitting diode (LED), emitting infrared light toward the emitting lens. The receiving device is a distance detecting sensor module, which senses the reflected light focused by the receiving lens. The distance detecting sensor further comprises an emitting light guide unit arranged between the emitting lens and the emitting device, and the emitting light guide unit comprises small round holes at the emitting tube core of the emitting device.

Abstract: In a sensor-fuzed munition system and method, the munition is provided with an additional laser designator/repeater mode of operation. In the laser designator/repeater mode, the munition has the option of initiating a target strike additionally based on whether a laser appointer energy is detected as being present on the target. The laser appointer energy signal is generated at a wavelength that is consistent with the wavelength of the laser rangefinder of the munition, and is generated based on the detected presence of a designator signal at a designator spot on the target. The laser appointer signal is directed to the designator spot and detected by the munition laser rangefinder receiver. In one embodiment, the repeater system for detecting the designator signal and for generating the appointer signal is provided on the delivery vehicle for the submunition.

Abstract: A system and method for registering 3D data sets is disclosed based on manual fiducial selection. The technique is useful in imaging obscured targets with 3-D imaging laser radars. For such an exemplary method, which defines a three-dimensional linear shift vector for each data voxel, four fiducials are required to completely define the mapping for a 3D space. An exemplary registration algorithm as disclosed provides an approach to automatically make fine adjustments to the 3D data registration. The tedious technique of shifting data sets relative to each other, in many degrees of freedom, is eliminated. Instead, a fine adjust is applied to the digital mapping function, through fiducial perturbation.

Abstract: Control modules for automatically adjusting a laser output based on a range to an object detected within a field of view are disclosed.

Abstract: Haze-type phase shift error due to stray light reflections in a phase-type TOF system is reduced by providing a windowed opaque coating on the sensor array surface, the windows permitting optical energy to reach light sensitive regions of the pixels, and by reducing optical path stray reflection. Further haze-type error reduction is obtained by acquiring values for a plurality (but not necessarily all) of pixel sensors in the TOF system pixel sensor array. Next, a correction term for the value (differential or other) acquired for each pixel in the plurality of pixel sensors is computed and stored. Modeling response may be made dependent upon pixel (row, column) location within the sensor array. During actual TOF system runtime operation, detection data for each pixel, or pixel groups (super pixels) is corrected using the stored data. Good optical system design accounts for correction, enabling a simple correction model.

Abstract: A method for inputting information by an input device with photosensitive elements uses laser light to illuminate a target and two photosensitive elements to sense the time at which beams reflected by the target and then reflected respectively by rotatable first and second mirrors, and determines an included angle between a virtual connecting line of the target and the first mirror and a virtual connecting line of the first mirror and the second mirror and an included angle between a virtual connecting line of the target and the second mirror and the virtual connecting line of the first and second mirrors depending on the time, thereby calculating a coordinate of the target and taking it as relative input information, capable of saving the time for obtaining the target's coordinate and the production cost of the input device.

Abstract: A system and method for viewing an object in a visually obscured environment includes a laser for generating a beam of light which is directed at the object. A pulse generator generates a reference pulse which triggers the laser and also a triggers a range generator which generates a range window positioned at a desired range. A gated optical detector (1) receives reflected light from the object, (2) receives the range window from the range generator, and (3) produces a gated optical output which contains reflections from ranges corresponding with the range window. A display is connected to the gated optical detector for displaying the gated optical output. In one embodiment, the transmitted light beam is polarized, and the received light beam passes through a selectable polarizing filter. In another embodiment, a plurality of received reflected light returns are integrated into a combined image.

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: An optomechanical switching device, a control system, and a graphical user interface for a photopolarimetric lidar standoff detection that employs differential-absorption Mueller matrix spectroscopy. An output train of alternate continuous-wave CO2 laser beams [ . . . L1:L2 . . . ] is directed onto a suspect chemical-biological (CB) aerosol plume or the land mass it contaminates (S) vis-à-vis the OSD, with L1 [L2] tuned on [detuned off] a resonant molecular absorption moiety of CB analyte. Both incident beams and their backscattered radiances from S are polarization-modulated synchronously so as to produce gated temporal voltage waveforms (scattergrams) recorded on a focus at the receiver end of a sensor (lidar) system. All 16 elements of the Mueller matrix (Mij) of S are measured via digital or analog filtration of constituent frequency components in these running scattergram data streams (phase-sensitive detection).

Abstract: A method and system for determining a level of a substance in a container, the method comprises emitting one pulse from a light source in a field of illumination toward a surface of said substance in said container. A backscatter signal of said pulse is detected by an optical detector. A lidar trace is created from said backscatter signal, said lidar trace including at least one reflection peak; A surface reflection is identified among said at least one reflection peak in said lidar trace, said surface reflection being a reflection of said pulse from said surface. The surface reflection is signal-fitted to provide a fitted surface trace. A level of said substance is determined in said container using said fitted surface trace.

Abstract: A description is given of a radiation sensor for detecting the position and intensity of a radiation source. The radiation sensor includes at least one photodetector having a radiation-sensitive surface. Furthermore, the radiation sensor includes a reflector that reflects the radiation emitted by a radiation source from specific directions at least partly in the direction of the radiation-sensitive surface of the photodetector. The reflector is arranged on that side of the radiation sensor that is remote from the radiation source.

Abstract: A technique for selecting two or more wavelengths of output light by a simpler structure is provided. A laser apparatus includes a laser oscillation portion for oscillating laser light; a nonlinear crystal inputting the laser light from the laser oscillation portion as a fundamental wave, the nonlinear crystal converting the fundamental wave into a second harmonic wave and changing conversion efficiency according to a temperature thereof, the nonlinear crystal having a periodically poled structure; and a ratio control means for controlling a ratio of the fundamental wave and the second harmonic wave outputting from the nonlinear crystal by controlling the temperature of the nonlinear crystal.

Abstract: A compact optical payload for an unmanned aircraft includes two infrared cameras for wide and narrow field viewing, a daylight color camera, a laser pointer and a laser range finder.

Abstract: A light emitting element and a light receiving element is placed in such a manner that the light axis of a light emitting element constructing a light emitting circuit and the light axis of a light receiving element constructing a light receiving circuit cross each other. The light pathway length R1, R2 of both the light waves are determined in such a manner that the object light, the light waves via the object pathway, are delayed by ?/2 in phase from the reflected light, i.e. relative to light waves via the reflected light pathway. A synchronous detector selects signals having the same phase as the object light from receive signals provided from the light receiving circuit. Accordingly, the fog detector can detect the object light without being influenced of the reflected light, which allows a determination processing device to accurately determine the density of fog.

Abstract: A distance measuring apparatus for measuring a distance to a target point in a target area comprises a laser oscillator for generating a laser beam having a first wavelength, a nonlinear crystal into which the laser beam having the first wavelength generated by the laser oscillator enters, the nonlinear crystal generating a laser beam having a second wavelength, a collimator lens at which the laser beam having the first wavelength generated by the laser oscillator and the laser beam having the second wavelength generated by the nonlinear crystal are concentrated and are transformed into parallel light flux, a laser device provided with the laser oscillator, the nonlinear crystal, and the collimator lens, an output unit for outputting the laser beam having the first wavelength and the laser beam having the second wavelength at the same time, which are emitted by the laser device, while scanning the target area, a selective reflective mirror for selectively reflecting the laser beam having the first wavelength

Abstract: By using 3-D focal plane arrays, the present invention tracks or locates small moving objects, or generates a 3-D frame of data with minimum laser energy and a minimum of mechanically moving parts. In another embodiment the invention is used to determine the direction of a laser designating a target with a minimum of moving parts. In another embodiment the invention is used as a 3-D movie/video camera. In yet another embodiment the device is used to provide data for autonomous navigation.

Abstract: A light detection and ranging (LIDAR) apparatus is provided that employs one or more additional reflectors to reflect and redirect the light beam transmission pulses from a scanning fan assembly to a given area of interest. The one or more additional reflectors provide additional resolution for detecting a detectable object. The one or more additional reflectors can be external or internal to the scanning fan assembly.

Abstract: The invention relates to a range finding method for a target by means of a pulsed laser (4) and a device for detecting pulses backscattered by the target, which comprises a step for emitting pulses with a repetition frequency f. The detection device comprises an array of photodiodes (21) associated with integrators (22?).

Abstract: A distance measurement module includes: an image pickup lens capturing an image of a subject; a light source unit disposed to be adjacent to the image pickup lens and irradiating reference light to the subject; a light receiving unit extracting image information of the subject and distance information to the subject upon receiving light which is reflected from the subject and made incident through the image pickup lens; and a calculation unit calculating the distance to the subject by using a phase difference between the reference light and the reflected light.

Abstract: An interferometric method and system enabling light echoes-to-spectrum mapping, applicable for laser rangefinder, biomedical imaging including surface 3D mapping and tomography, vehicle position identification, and spectrum analysis. The direct mapping into spectrum allows a time-of-flight detection without using any timing pulse modulation. The sensitivity of the detection can be as high as that of the conventional low coherence interferometry, thereby an eye-safe and low-cost solution not compromising performance. In a practical implementation, high accurate range detection can be easily achievable with the level of accuracy equivalent to the laser rangefinder using a 20 ps Full-Width-at-Half-Maximum (FWHM) timing pulse. The system and method comprise applying dispersion-unbalanced interference (referred to as ‘cross-chirp interference’) and gating a phase matched spectral component.

Abstract: A 3D pulsed laser projection system scans an object to produce a dense 3D point cloud and projects a laser light beam onto an object as a glowing template. A high-sensitivity optical feedback system receives and detects a feedback beam of the output beam light diffusely reflected from the object. The feedback light and projected beam share the same beam path between steering mirrors and the object. A light suppression component controls stray scattered light, including ambient light, from being detected. A time-of-flight measurement subsystem provides a distance-to-object measurement for projected pulses. An acousto-optical modulator, variable gain detected signal amplification and variable photo-detector power together produce a dynamic range for detected reflected feedback signals of at least 100,000, and up to 500,000. Optical fiber cables spatially filter scattered light and isolate the photo-detectors thermally.

Abstract: A handheld rangefinder device operable to determine ballistic hold-over information is disclosed. The rangefinder device generally includes a range sensor operable to determine a range to a target, a memory storing a database of ranges and corresponding hold-over values for a default sight-in distance, and a computing element, coupled with the range sensor and the memory. The computing element may calculate an adjusted hold-over value based on the range and an actual sight-in distance. Additionally, a tilt sensor may be included to provide information for calculating an angle-adjusted hold-over value. Such a configuration facilitates accurate firearm use by providing ranges and hold-over values without requiring time-consuming and manual user calculations.

Abstract: The present invention relates to a method for laser ranging with high precision and high efficient, a method for identifying distance mode automatically during laser ranging process, and a laser ranger with high precision, high efficient and low power waste. The accuracy of ranging is increased through multi classes of receiving process; the accuracy of ranging is further increased through the selection of distance mode and the adjustment of receiving sensitivity before the measuring steps are executed; the accuracy of ranging is further increased through executing jitter judgment on obtained distance measured values to discard the distance measured values that do not satisfy the setting conditions and judge whether the number of remaining distance measured values satisfies the setting quantity requirement; and the present invention is also of simple structure, high measurement efficiency, and low power waste.

Abstract: A light detection and ranging system includes a transmitter transmitting a transmitted light pulse timing sequence, with pseudo-random timing and including a plurality of light pulses, toward a target. An optical receiver receives a reflected light pulse timing sequence including a plurality of light pulses from the target. An electronic control unit identifies a time delay between the transmitted light pulse timing sequence and the reflected light pulse timing sequence as a function of a correlation between the transmitted and reflected light pulse timing sequences.

Abstract: A centroiding method is provided for an optical tracking system including a laser used for countermeasuring purposes in which a pencil thin laser beam is accurately positioned onto a target through the use of centroiding techniques for ascertaining the position not only of the target but also the laser beam, with the centroiding techniques resulting in a sub-pixel level resolution. The sub-pixel resolution permits utilization of smaller cost-effective focal plane arrays by giving the small focal plane array a resolution associated with much larger focal plane arrays.

Abstract: The present invention includes a multifaceted imaging semi-active laser system (“I-SALS”). In one aspect, the I-SALS closes on a laser designation of a target until it starts imaging the target, whereupon the I-SALS then homes on the target from the image. Some embodiments employ a slightly defocused designation. Other embodiments use existential jitter in the designation and other embodiments intentionally induce a jitter in the designation called dither. One particular embodiments provides a dual field-of-view optics package that has no moving parts.

Abstract: Provided are a distance measuring sensor including a double transfer gate, and a three dimensional color image sensor including the distance measuring sensor. The distance measuring sensor may include first and second charge storage regions which are spaced apart from each other on a substrate doped with a first impurity, the first and second charge storage regions being doped with a second impurity; a photoelectric conversion region between the first and second charge storage regions on the substrate, being doped with the second impurity, and generating photo-charges by receiving light; and first and second transfer gates which are formed between the photoelectric conversion region and the first and second charge storage regions above the substrate to selectively transfer the photo-charges in the photoelectric conversion region to the first and second charge storage regions.

Abstract: A method of determining a distance to an object is presented. A first photon and a second photon are simultaneously generated. The first photon is reflected off an object. The second photon is directed to an optical cavity. An arrival of the first photon is correlated with an arrival of the second photon, and the distance to the object is at least partially determined using the correlation.

Abstract: A coordinate measurement instrument includes an optical distance measurement device (200, 300) for measuring the distance from an auxiliary measurement means (5) which can move in space, a zoom camera (106), which can rotate with respect to at least two axes, with a zoom lens, and an overview camera (104) for coarse localization of the auxiliary measurement means (5). A light exit and light receiving optical system (101, 102) of the distance measurement device (200, 300), the zoom camera (106) and the overview camera (104) are arranged on a shared carrier (1) which can rotate with respect to at least two axes (A, Z). The optical axis (111) of the distance measurement device (200, 300) and the optical axis of the overview camera (104), preferably extend coaxially outside the coordinate measurement instrument.

Abstract: An object detection system for a vehicle includes an imaging device, an image processor and a Lidar device. The imaging device is operable to capture image data representative of a scene exterior the vehicle. The image processor processes image data to detect an object of interest in the field of view of the imaging device. The Lidar device is responsive to the image processing so as to have its line of sight guided to point toward the detected object of interest. The Lidar device is operable to measure the distances between the host vehicle and the detected object of interest.

Abstract: A distance measurement method for use in a laser range finding device to measure a distance between the laser range finding device and a target is disclosed. The method comprises the following steps. A laser signal is sent to the target in a first time point. A reflected laser signal reflected by the target is then received. A digital signal having a plurality of signal values ranging from 0 to N is obtained by sampling the reflected laser signal with a sampling signal, wherein N is an integer larger than two. A maximum signal value among the signal values is obtained. The distance is calculated according to the first time point and a second time point where the maximum signal value is generated.

Abstract: A simulation system for predicting a likelihood of whether a target object positioned in an environment will be detected by a detection system when illuminated by a laser source. The simulation system may be used for a laser rangefinder application and a laser designator application. The simulation system may provide a detection probability of the target object at a specified range to the detection system or a plurality of detection probabilities as a function of the range to the detection system. The simulation system may provide an indication of an overlap of the beam provided by the laser source on the target object. The simulation system may determine the effect of vibration on the detection of the target object at a specified range.

Abstract: An optical sight includes an outer barrel unit, an objective lens unit, an ocular lens unit, a magnification unit, a range-finding module, and a display unit. The objective lens and the ocular lens unit are mounted to front and rear ends of the outer barrel unit, respectively. The magnification unit is disposed between the objective lens unit and the ocular lens unit. The range-finding module is disposed on the magnification unit, and includes a light emitter, a light receiver, and a micro processing unit. The display unit is disposed in the outer barrel unit, and includes a seat mounted adjustably between the magnification unit and the ocular lens unit, and a transparent display secured to the seat and coupled electrically to the micro processing unit. The transparent display has an aiming indicator, and a message indicator for visual indication of a range calculated by the micro processing unit.

Abstract: Systems and methods are provided that employ one or more mirrors to harvest laser beams emitted by a physical rangefinder within a region of interest that would otherwise not intersect an object within the region of interest. The mirrors redirect the harvested beams back within the region of interest, creating one or more virtual rangefinders that supplement the physical rangefinder. The location of the virtual rangefinders is symmetric to the position of the physical rangefinder about the plane of the mirror and along the line normal to the mirror passing through the physical rangefinder. The virtual rangefinders, which operate synchronously with the physical rangefinder, thus provide a view of the object(s) from an angle different from that of the physical rangefinder.

Abstract: A coherent imaging system for producing high resolution images is provided. A coherent radiation source module produces two radiation beams, each at a different instance. An optical component directs the first radiation beam towards a target at a first angle to produce a first return beam, and also produces a first reference beam. Another optical component directs the second radiation beam towards the target at a second angle to produce a second return beam, and also produces a second reference beam. An aperture collects the first return beam and the second return beam. A detector module produces two coherent images based on interference between the return beams and the reference beams. The detector module also combines the first coherent image and the second coherent image to produce a high resolution coherent image, which has a resolution higher than a resolution of the first coherent image or the second coherent image.

Abstract: Range binoculars capable of measuring a distance between the observation place and an object, the binoculars being made small-sized with keeping the functions as binoculars.

Abstract: The invention is based on a distance-measuring device having a transmission unit (20) for generating a transmission signal (42) having at least one measurement frequency (f1, f2) which is desired for detecting distance information. It is proposed that the transmission unit (20) comprises a means (60) for generating an evaluation signal (62) having an evaluation frequency (fA) which is desired for evaluating the distance information.

Abstract: A three-dimensional range imager includes a light source for providing a modulated light signal, a multiplexer, an optical fiber connecting the light source to the multiplexer, a plurality of optical fibers connected at first ends to the multiplexer and at second ends to a first fiber array, and a transmitter optic disposed adjacent the first fiber array for projecting a pixel pattern of the array onto a target.

Abstract: A range finder is provided. A light emitting unit emits a light pulse. A light receiving unit senses an incident light pulse. A reflective mirror reflects the light pulse emitted from the light emitting unit to an outside space and reflects the light pulse incident from the outside space to the light receiving unit. An actuator is configured to move the reflective mirror in a first direction rotating about a vertical axis and a second direction rotating about a horizontal axis. A controller controls the light emitting unit and the light receiving unit and driving the actuator. The actuator includes: a rotation motor unit supporting the reflective mirror to be rotated in the second direction and rotating the reflective mirror in the first direction; a bushing hinge-coupled with the reflective mirror to rotate in the first direction together with the reflective mirror and installed movably in a vertical direction; and a vertical driving unit moving the bushing in the vertical direction.

Abstract: Emitting stripe pattern light, whose intensity changes periodically, onto a subject while shifting the phase of the pattern by ?/2 from a reference phase of 0 until the phase is shifted one cycle to receive reflected light by an image sensor at each of phases 0, ?/2, ?, and 3?/2. From received light signals obtained at four phases, calculating a phase difference between the stripe pattern light and reflected light thereof with respect to each light receiving element to calculate distance information representing a distance to the subject based on the phase difference. In this case, the distance information is calculated only from a light receiving element having an absolute value of the difference between a first added signal of received light signals at 0 and ? and a second added signal of received light signals at ?/2 and 3?/2 smaller than a specific value.

Abstract: A method for evaluating distance from a first point to a second point. The method includes the steps of generating a periodic binary sequence, generating a harmonic modulation signal, generating a modulated light signal at a range finding device, wherein the modulated light signal is generated based upon the periodic binary sequence and the harmonic modulation signal, transmitting the modulated light signal from the first point toward an object at the second point, receiving a reflected light signal from the object, and determining a distance between the first point and the second point based upon a phase evaluation of periodic binary sequence and harmonic modulation signal of both the transmitted light signal and the received light signal.

Abstract: A signal processing apparatus includes a phase shift unit and a signal processing unit. The phase shift unit shifts phases of at least one set of first periodic signals and second periodic signals. The first periodic signals are output from an optical signal output device connected to a displacement detection target and have amplitude gradually increasing with a displacement in a predetermined direction of the displacement detection target. The second periodic signals are output from the optical signal output device connected to the displacement detection target and have amplitude gradually decreasing with the displacement in the predetermined direction of the displacement detection target. The signal processing unit executes a predetermined operation with respect to the first and second periodic signals output from the phase shift unit to obtain a displacement of the displacement detection target.

Abstract: A laser distance measuring apparatus and control method thereof includes an emitter, a first and second liquid crystal display module, a receiver, a condensing lens, and a control unit. The emitter emits measuring light. The control unit sets the first liquid crystal display module to a second state and the second liquid crystal display module to a first state to receive the reflected light. When the reflected light is larger than a predetermined value, the control unit adjusts a transmittance of the first liquid crystal display module until the reflected light is lower than the predetermined value, and calculates a distance value based on phase difference between the reference light and the reflected light.