Abstract: A sensor using laser range imaging technology is adapted for determining a three-dimensional profile of a vehicle passing the sensor for use in Intelligent Vehicle Highway Systems. A continuously pulsed laser beam scanned across a detection area determines the presence of a vehicle. Range, angle and time date for a vehicle passing the sensor are collected and stored for use in determining its three-dimensional profile. Forward and backward beams are directed for scanning across the detection area. Pulsed energy is sent into the two divergent beams, which are received as reflective energy in a receiver. The receiver accepts reflections from the beams and provides inputs for purposes of determining time of flight, and for measuring the time interval between interceptions of the two divergent beams for a given vehicle. An encoder tracks the position of the mirror for providing angle data with associated range measurements.

Abstract: A method and apparatus for imaging a scene. The method and apparatus are capable of resolving 3D spatial structure within the scene. The apparatus includes a light source, a timing system and a detector system. The light source emits pulses of light toward the object or target scene being imaged. In one embodiment, the light source is a laser. In another embodiment, the detector system includes an optical system and a monolithic array of light detectors operating in non-linear Geiger-mode. The optical system collects a portion of the light scattered off of objects in the target scene and directs the collected light toward the array of light detectors. In another embodiment, the detector system includes an optical system and a single light detector operating in non-linear Geiger-mode. In this embodiment, the optical system scans the target scene, collects a portion of the light scattered off of objects in the target scene and directs the collected light toward the light detector.

Abstract: A multi-function day/night observation, ranging, and sighting device includes a single first lens and a single eyepiece lens and provides an image of a scene. The single first lens leads to a visible-light first optical path and to an invisible-light second optical path. The invisible-light second optical path includes an image intensifier tube providing a visible image. The first and second optical paths converge with visible images provided by each pathway being overlaid at a reticule plane. A single light path leads from the reticule plane to the eyepiece lens. A laser provides a pulse of laser light projected into the scene via the single first lens, and the image intensifier tube is used as a detector for a portion of the laser light pulse reflected from an object in the scene in order to provide a laser range finding function.

Abstract: A circuit and apparatus for generating a light pulse from an inexpensive light-emitting diode (LED) for an accurate distance measurement and ranging instrument comprises an LED and a firing circuit. An optional pre-biasing circuit provides a reverse-bias signal to the LED to ensure the LED does not begin to emit light before a firing circuit can provide a sufficiently high current pulse of short duration as a forward current through the LED. The LED is driven by the firing circuit with a pulse of high peak power and short duration. The resulting light pulse from the LED can be inexpensively used to derive distance and ranging information for use in a distance measurement and ranging device.

Abstract: A multiplexer for laser range finders and the like has a plurality of laser transmitters disposed about the periphery thereof. Each of the laser transmitters transmits a beam which is substantially smaller than the return beam received by the laser receiver. The laser receiver and each of the laser transmitters are configured to have a substantially common optical axis such that laser beams transmitted by the laser transmitters substantially overlap at a plane of interest so as to provide enhanced illumination thereby.

Abstract: A highly precise range measurement instrument is made possible through the use of a novel and efficient precision timing circuit which makes use of the instrument's internal central processing unit crystal oscillator. A multi-point calibration function includes the determination of a "zero" value and a "cal" value through the addition of a known calibrated pulse width thereby providing the origin and scale for determining distance with the constant linear discharge of capacitor.

Abstract: An automated vehicle guidance system for guiding a movable vehicle along a predetermined desired path over a surface that is provided with at least one reference marking includes a laser radar for emitting laser pulses towards the reference marking and for receiving laser pulses reflected from the reference marking, a steering actuator for steering the vehicle, and a computer connected to the laser radar and the steering actuator. The laser radar is designed to determine the distance between the vehicle and the reference marking and that distance is used by the computer to determine the lateral position of the vehicle relative to the desired path of vehicle travel. The computer then controls the steering actuator in the manner necessary to effect guidance of the vehicle along the desired path.

Abstract: A radar apparatus comprises a rotary polygon mirror with a plurality of mirror surfaces inclined at different angles. A semiconductor laser diode and a collimator lens are disposed above the polygon mirror. An infrared pulse beam emitted from the semiconductor laser diode is reflected by a reflection mirror disposed at an upper position in front of the polygon mirror to reflect the pulse beam obliquely downward toward the rotary polygon mirror so that the pulse beam is reflected as a transmission beam advancing toward a measuring area in a forward direction. A light receiving means receives the transmission beam returned from an object positioned within the measuring area.

Abstract: A distance measuring apparatus measures the time an emitted optical pulse requires to go and return the distance to a target before being received by using the emission time and the reception time of the optical pulse, and obtains the distance to the target from the measured time. A converter converts an optical pulse received by a photodetector into an electrical signal. A divider divides the electrical signal pulse into two signal pulses. A delay element delays only one signal pulse. Both the undelayed and delayed pulses are applied to a threshold generator. The threshold generator generates and holds the value of signal intensity at the intersection of waveforms of the two pulses as a threshold value of the received signal pulse. A comparator generates a digital signal pulse indicating the reception time from the received signal pulse by using the generated threshold value.

Abstract: An optical path degradation detecting device having a laser distance detector which uses a laser beam to detect the distance between two objects and which generates distance signals representative of the distance between the two objects. A first predetermined point signal is generated upon the distance signals being in a distance representative of a first predetermined distance or less, and a second predetermined point signal is generated upon the distance signals being in a distance representative of a second predetermined distance or less, wherein the second predetermined distance is less than the first predetermined distance. A fault signal is generated if the second predetermined point signal is generated within a predetermined time interval relative to the generation of the first predetermined point signal.

Abstract: A laser ranging system which includes a laser pulse emitter, an imaging and impingement detecting amplifier and a system processor is provided. The laser pulse emitter produces a pulse of light to be reflected by at least one object at an unknown distance from the laser emitter. The detecting sensor has a multiplicity of photoelements and collects reflected light from the object. The detecting sensor determines the intensity of the reflected light and the time it first impinged on each of the photoelements. The system processor controls the laser pulse emitter and the detecting sensor. The system processor also receives output from the detecting sensor to produce at least distance indications for the object based on the length of time from emission of the pulse of light to receipt of its reflection as sensed by each of the photoelements.

Abstract: In a vehicle laser radar system capable of performing both distance measurements and information communication, only one laser diode is required. A light beam output by a first light emitting section (10) is split and applied through an optical cable to a second light emitting section (14), so that the light beam thus split is emitted from the second light emitting section. A control unit places the laser diode in an operating state for a predetermined period of time, and, when the laser diode is in an operating state, chooses between distance measuring data or communicating data alternately, and causes the laser diode to emit a light pulse according to the data thus chosen.

Abstract: An obstacle detecting apparatus for ensuring that the transmitted light power is sufficient to detect an obstacle at a long distance, but yet not be harmful to human eyes. The apparatus comprises a light transmitting device for transmitting a pulsed light in a plurality of angular directions, and a light receiving device for receiving the light reflected from an object. The distance to the object is based on the time difference between transmission of the light and reception of the reflected light, and the power of the transmitted light is controlled in each angular direction such that reception intensity of the reflected light in every angular direction can be within a predetermined range.

Abstract: Portable, lightweight, compact, eye-safe, battery-operated laser range finder and digital compass assembly, mountable onto a personal weapon or aiming device, to accurately measure distance, azimuth and elevation angle of a target and increase the accuracy and probability of the hit. The laser range finder and digital compass assembly has a laser transmitter for transmitting an output laser beam having a wavelength in the range of 1.0 to 1.1 microns, an OPO converter for converting the output laser beam to an eye-safe range between 1.5 and 2.

Abstract: A modulated LIDAR system is disclosed, in which a laser for generating an tical carrier signal and a microwave generator for generating a coded microwave signal are provided. A modulator is further provided for modulating the carrier signal with the microwave signal, whereby a modulated signal is generated. A method of detecting a reflective surface is also disclosed, in which an optical carrier signal is generated, the carrier signal is modulated with a coded microwave signal, the modulated signal is reflected off of a reflective surface and the reflected signal is recovered.

Abstract: In a laser radar (lidar) system, a Doublet Pulse is generated by injection-seeded aborted cavity dumping of a solid-state laser. The doublet pulse provides coherent Doppler lidar systems a substantial time bandwidth product (TB) with a very modest processing requirement. The waveform format comprises a pair of pulselets, each of duration .tau., separated by T seconds. The range resolution is governed by the pulselet duration .tau., while the velocity precision is governed by one over the pulselet separation, T. Ambiguities in the velocity measurement arise as a result of the periodic structure of the waveform and occur every .lambda./2T m/sec, where .lambda. is the operating wavelength. These ambiguities are removed by conventional de-aliasing algorithms as well as through the generation and processing of higher order pulse waveforms.

Abstract: A device for measuring distance with a visible measuring beam (11) generated by a semiconductor laser (10), a collimator object lens (12) to collimate the measuring beam towards the optical axis (13) of the collimator object lens (12), a radiation arrangement to modulate the measuring radiation, a reception object lens (15) to receive and image the measuring beam reflected from a distant object (16) on a receiver, a switchable beam deflection device (28) to generate an internal reference path between the semiconductor laser (10) and the receiver and an electronic evaluation device (25) to find and display the distance measured from the object. According to the invention, the receiver contains a light guide (17') with a downstream opto-electronic transducer (24), in which the light guide inlet surface (17) is arranged in the imaging plane of the reception object lens (15) for long distances from the object and can be controllably moved (18') from this position (18) transversely to the optical axis (14).

Abstract: A vehicle environment monitoring system is capable of monitoring the nearly entire region around a vehicle on which the system is installed, and is protected from staining or damaging. The system includes an optical radar apparatus comprising a light transmitter for generating and irradiating a beam of light; a scanner with a reflective mirror rotatably disposed on a support shaft in an inclined manner for scanning the light beam in the surroundings of the vehicle; and a light receiver for receiving the light beam reflected from an object. The apparatus is disposed on the ceiling inside or outside the subject vehicle, or on a bumper at a front or rear corner of the vehicle.

Abstract: A measuring system includes a first circuit that produces a first signal. A transmission line has a first end and a second end where the first end is interconnected with the first circuit so as to receive the first signal. A second circuit is remotely located from the first end of the transmission line and interconnected with the second end of the transmission line so as to detect the first signal. The second circuit in response to detecting the first signal produces a second signal that is received by the second end of the transmission line. The first circuit detects the second signal and in response determines the length of the transmission line. The first signal and the second signal preferably have different frequencies and the transmission line is preferably a fiber optic cable.

Abstract: A pre-biasing technique for a transistor-based avalanche circuit which improves the initial rate of rise in the current applied through a laser diode or other light emitting device in a laser based distance measurement and ranging instrument and, therefore, the sharpness of the leading edge of the laser pulse produced. Since the timing of the flight time of a laser pulse to a target and back to the ranging instrument is determined with reference to the leading edge of the emitted laser pulse, the inherent precision obtainable is enhanced by the production of a sharper leading edge pulse. Through the use of the pre-biasing technique disclosed, the very rapid rise time pulse which may be achieved also allows for the substitution of a much cheaper light emitting diode in lieu of a conventional laser diode in an alternative implementation of a light pulsed-based distance measuring and ranging instrument.

Abstract: A system and technique for a laser rangefinder which uses a low peak power aser, scanner, and beam scanning device with a linear detector where target range corresponds to individual detector elements to enhance signal-to-noise ratio and maximum target range.

Abstract: N lines of line-shaped light are projected onto the object by means of a measuring light projecting lens. The light carrying the image of the object is passed through the eyepiece lens 17 in an endoscope 6 and the auxiliary lens 30 in a measuring head 11 and split into two beamlets by a beam splitter 31, with one beamlet being focused at a position coinciding with the entrance end faces of measuring light's position detecting fibers 33(l) to 33(m). The line-shaped light images of the object thus formed in positions coinciding with the entrance end faces of measuring light's position detecting fibers 33(l) to 33(m) are scanned linearly by those linearly aligned fibers as they are oscillated and driven by a fiber scanner 36. The scanned line-shaped light images are then subjected to the necessary signal processing in a signal processor circuit 35 such as to measure the three-dimensional configuration of the object.

Abstract: A coaxial electro-optical distance meter has optical elements on light transmitting side which are located behind an objective lens such that light from a light transmitting member is reflected from a first reflecting surface disposed adjacent to an optical axis of the objective lens. The reflected light is emitted as transmitted light to a reflecting member disposed ahead of the objective lens. Optical elements on light receiving side are arranged such that received light from the reflecting member is reflected from a second reflecting surface disposed behind the first reflecting surface for guiding it to a light receiving member disposed beside the optical axis. The first reflecting surface is disposed such that the optical axis is positioned inside a luminous flux of the transmitted light.

Abstract: A "laser tape measure" for measuring distance which includes a transmitter such as a laser diode which transmits a sequence of electromagnetic pulses in response to a transmit timing signal. A receiver samples reflections from objects within the field of the sequence of visible electromagnetic pulses with controlled timing, in response to a receive timing signal. The receiver generates a sample signal in response to the samples which indicates distance to the object causing the reflections. The timing circuit supplies the transmit timing signal to the transmitter and supplies the receive timing signal to the receiver. The receive timing signal causes the receiver to sample the reflection such that the time between transmission of pulses in the sequence in sampling by the receiver sweeps over a range of delays.

Abstract: A scanning-type distance measurement device is responsive to selected signals to reduce interference due to stray light. An emitted beam of light is aimed to be reflected from an object and to a photodetector among a plurality of photodetectors which are positioned linearly or in two-dimensions. The outputs of the photodetectors are selected based on the position of the emitted beam of light, so that photodetectors which should not contribute to the reflected beam, based on the geometry of the emitted beam and the reflecting object, are ignored. This approach reduces the effects of stray noise from other light sources. The selection of the photodetectors is synchronized with a scanning light emitter generating the beam of light by a position signal and an angular signal so that the noise component in the output signal which is due to stray light can be kept to a minimum.

Abstract: An apparatus of for measuring roughness of a road surface such as convex, concave or inclination is to be mounted on the vehicle. The apparatus comprises a rotation driving member for generating rotation motion in vertical plane and for outputting a signal concerning its rotation angle. An inclinometer is provided to detect an inclined angle of the rotation driving member. A distance measuring member for measuring distance from road surface as being rotated by the rotation motion from said rotation driving member. A processing unit calculates a vertical distance and a horizontal distance between the apparatus and the road surface by means of the inclined angle detected by the inclinometer and the rotation angle detected by the rotation driving member.

Abstract: A distance measuring apparatus for a vehicle including: an irradiating means for emitting and irradiating an electromagnetic wave; a receiving means for receiving a reflected wave produced when the electromagnetic wave is reflected by an obstacle and generating a receiving signal; a propagation delay time period measuring means provided with a comparison value set such that a value for a comparison reference is larger in a case in which a propagation delay time period from irradiating to receiving the electromagnetic wave is shorter than in a case in which the propagation delay time period thereof is longer for comparing the receiving signal with the comparison value, recognizing a time point at which the receiving signal is equal to or larger than the comparison value when the receiving signal is compared with the comparison value as a receive detecting time point and measuring the propagation delay time period from a time point at which the irradiating means irradiates the electromagnetic wave to the receiv

Abstract: A length and elongation sensor includes an elastomeric optical wave guide d a time domain reflectometer. The elastomeric optical wave guide consists of a urethane outer cladding and an optical gel core. A transparent window is hermetically sealed to the first end of the optical wave guide and a reflective mirror is hermetically sealed to the second end of the optical wave guide. Both ends of the wave guide are then fixedly attached to the unit to be measured. The time domain reflectometer is operative for propagating a light pulse through the optical wave guide and for measuring the round-trip propagation time of the light pulse. Since the velocity of the light pulse is known, the length of the wave guide can easily be determined. The wave guide is stretchable up to 25% of its original length thereby allowing both static and dynamic length measurements of the unit to be measured.

Abstract: An improved circuit and method of making precise time of arrival measurements on optical pulse data of relatively varying widths. The invention provides an analog input pulse representing received optical pulse data, along with a delayed version of the analog input pulse. The time of delay is set such that the original analog pulse and the delayed analog pulse cross each other at a predetermined point. This cross-over consistently occurs at the same point on the signal independent of the size or shape of the analog pulse. Preferably, the cross-over occurs at approximately 70% of the analog pulse amplitude. The cross-over point between the original pulse and the delayed pulse triggers the generation of the leading edge of a time of arrival pulse.

Abstract: A distance measuring equipment which can detect a beam sending direction with a compact and simple structure is provided.The distance measuring equipment is equipped with a scanning means which swings a reflection means in a predetermined range to scan a beam, an original point detecting means which detects the original point as a reference position of the reflecting means, and a beam sending direction operating means which calculates a direction of the sending beam reflected by the reflecting means based on a detected output from the original point detecting means.

Abstract: A distance measuring apparatus has: light receiving means for receiving light which is emitted from a light emitting element unit and reflected from an obstacle having a reflecting surface, a pair of members of high reflection performance being respectively disposed on portions of the reflecting surface; and a calculating circuit for calculating a distance from the obstacle on the basis of a time period between the emission and the reception of the light. According to the apparatus, in a measurement range of a short distance where light reflected from a reflecting surface positioned between the pair of members of high reflection performance is received, the maximum amount of light received by the light receiving means is set to be smaller than a sensitivity at which a snowfall is detected, and the minimum amount of light is reduced to a level at which an obstacle positioned at the short distance can be detected.

Abstract: A system and method for determining wind velocity. The LIDAR 104 transmits a plurality of laser pulses. The paths of the laser pulses surround a center line (206) that does not coincide with a vertical axis (706) intersecting the LIDAR (104), i.e., an off-vertical scan. Each laser pulse reflects off particles in the air at a given location. This location is the intersection of the path of each LIDAR pulse and the target altitude. The target altitude is the altitude at which the wind velocity is to be determined. The reflected pulses are received by the LIDAR (104). The invention groups the received LIDAR pulses according to the altitude at which they were reflected, as opposed to the distance each pulse travels. Grouping the received pulses in this manner enables the invention to perform an off-vertical scan that accurately determines the wind velocity at a target altitude. The received laser pulses have an associated Doppler shift.

Abstract: Disclosed herein is a laser radar apparatus comprising a laser radar head section for measuring a distance to an object of detection, based on the time until laser light irradiated to the object of detection is reflected by the object of detection and returns, and a laser radar control section for performing laser irradiation control of the laser radar head section and also performing various kinds of calculation processes, based on the result of the distance measurement. The laser radar head section is provided with an identification function of identifying that the laser radar control section being connected is a regular laser radar control section.

Abstract: This laser telemetry device operating on the principle of the measurement of the transit time of a light pulse, is characterized in that it comprises:a passive switching microlaser (2),means (6, 10) for receiving a light pulse (18, 19) reflected by an object (4) and for the detection of the reception time of said pulse,means (8, 10) for the detection of the emission time of a pulse from the microlaser (2),means (12) for measuring the time interval or slot separating the microlaser pulse emission time and the reflected beam reception time.

Abstract: A distance measurement device comprising a light-sending unit for sending pulsed light toward an object of measurement where a distance thereto is measured, a light-receiving unit for receiving incident light including pulsed reflection light reflected by the object, a distance measurement unit for measuring the time from the sending of the pulsed light to the receiving of the incident light and calculating the distance to the object, and an interference detection unit for determining whether interference light exists in the incident light, based on the intensity of the incident light.

Abstract: In this vehicle optical radar apparatus, the number of parts constituting an oscillating mechanism can be reduced, assembling facilities can be improved, an accumulated error of the parts can be decreased, and light weight and low cost can be obtained. An oscillating member (29) consists of a resin-molded product constituted by a light-sending mirror holding portion (33), a light-receiving mirror holding portion (34), and a cylindrical member. A shaft (30) fitted with the cylindrical member of the oscillating member (29) and a rotating shaft (22a) of a pulse motor are pivotally supported by a housing (24) and a cover which are the case of the pulse motor and consist of a resin-molded product. A follower (36) is rotatably attached to a follower attachment plate (35) attached to the light-receiving mirror holding portion (34). The follower (36) is stored in an eccentric cam groove (26a) of the cam (26) fixed to the rotating shaft (22a).

Abstract: A laser range finder receiver for detecting a return pulse and providing an output signal indicative thereof and a single-chip microcontroller for controlling receiver operation and, in particular, for automatically recalibrating the receiver. The receiver is responsive to up and down current control signals from the microcontroller to adjust the bias of an APD photodetector. An offset voltage and receiver false alarm rate are monitored with no light on the photodetector while a calibration voltage is adjusted to recalibrate the receiver. The microcontroller further monitors photodetector temperature via a temperature sensor, and can perform APD bias adjustment and receiver recalibration in response to temperature changes, providing operation over a wide temperature range.

Abstract: A laser range finder that is modular so that it can mounted on different weapon platforms. A pulsed infrared laser beam is reflected off the target. The timed return signal is then used to measure the distance. Another laser, either a visible laser or another infrared laser of differing frequency, is used to place a spot on the intended target. Notch pass optical filters serve to eliminate ambient light interference from the second laser. The range finder using projectile information stored in the unit processes the calculated distance to raise or lower the finder on the weapon. A plurality of weapon platforms and projectile is selected by pressing the desired rubberized keypad. The range finder can be used with a laser detonated projectile that can be detonated when the projectile is over the target. The projectile is fitted with a detector that is sensitive to the frequency of a wide angle laser beam that is attached to the weapon.

Abstract: An optical radar apparatus which includes a light emitter for emitting light, a light transmitter and reflector for reflecting and transmitting the light, a reflected light reflector for receiving the light which has Keen reflected by an object, and for reflecting the received light, and a light-responsive device which is located in a horizontal direction from the light emitter, and which receives the light reflected by the reflected light reflector. A rotatable holding member holds the light transmitter and reflector and the reflected light reflector at predetermined positions relative to one another. A scanner rotates the holding member to scan the light in the horizontal direction.

Abstract: A laser based range finder which may be inexpensively produced yet provides highly accurate precision range measurements has a number of user selectable target acquisition and enhanced precision measurement modes which may viewed on an in-sight display during aiming and operation of the instrument. Extremely efficient self-calibrating precision timing and automatic noise threshold circuits incorporated in the design provide a compact, low-cost, highly accurate and reliable ranging instrument for a multitude of uses and is adaptable for both recreational and laser based "tape measure" applications.

Abstract: A laser beam type distance measuring device comprises a laser beam emitter; a returning laser beam detector; a polygon mirror rotated about a first axis for reflecting a going laser beam from the laser beam emitter toward a remote object and reflecting a returning laser beam from the object toward a given optical track along which the returning laser beam travels to the returning laser beam detector; and a nodding mechanism for pivoting the polygon mirror about a second axis which is perpendicular to the first axis. These parts are housed in a case which has a window opening through which the going and returning laser beams pass. An outwardly swelled transparent cover covers the window opening in such a manner that a depressed inner surface thereof faces toward the polygon mirror in the case. A shielding plate is installed in the case near the polygon mirror to prevent the going laser beam from entering the given optical track.

Abstract: A high-speed data register for storing a series of data values received at a high-speed clock rate and including a first set of pipelined latches and a second set of pipelined latches. Control circuitry loads the received data values alternately into said first set of latches and said second set of latches from an input or "last" register, which stores the last data value received by the data register. Data values thus enter the last register at the high-speed clock rate but are loaded into each of the first and second set of pipelined latches at one-half that rate.

Abstract: This invention discloses a laser imager for imaging a scene having targets comprising a laser scanner operative to scan the scene at a given spacing with a laser beam, a receiver which receives laser light reflected from the scene and determines the range and reflectance of an object reflecting said laser light at various scan positions and control logic which changes the given spacing in response to the determined range.

Abstract: A laser range finder including a receiver for detecting a return pulse and providing an output signal indicative thereof, a single integrated circuit digital range counter chip connected to receive the output signal from the receiver, a power supply unit for powering the receiver and range counter chip, and a single-chip microcontroller for selectively sequencing application of power to the receiver and to the range counter chip, for controlling laser firing, and for automatically recalibrating the receiver.

Abstract: An optical distance measurement apparatus comprises a system controller for controlling the entire operation of a system, a light emitting circuit for emitting a high-power pulse light beam as a distance measuring medium to an object in response to a drive signal from the system controller, a light receiving circuit for receiving a light beam reflected from the object, a trigger signal generation circuit for generating a trigger signal indicative of a start time point for measurement of a light moving time, and a time-distance conversion circuit for measuring the light moving time in response to the trigger signal from the trigger signal generation circuit and in response to an output signal from the light receiving circuit, and for converting the measured light moving time into a distance to the object.

Abstract: An obstacle detecting system for a motor vehicle which is capable of detecting not only the distance to an obstacle(s) existing in front of the motor vehicle and the width thereof, but also its height to thereby allow a motor vehicle control to be effected more appropriately with high reliability. The distance to the object and its width are detected by a laser radar type distance detecting unit, while the distance to the object lying within a window preset by a window setting device is also detected by a distance detecting circuit of a stereoscopic video camera unit. An object size determining unit is provided for selecting a window corresponding to a distance value detected by the stereoscopic video camera unit and which coincides with a distance value calculated by the laser radar type distance detecting unit, to thereby determine the size of the object on the basis of the preset position of the selected window.

Abstract: A distance measuring equipment which is useful in, for example, a collision prevention system wherein a laser beam is forward emitted from a vehicle to measure a distance between the vehicle and a forward vehicle, and an alarm is produced when the present vehicle abnormally approaches the forward vehicle. In the distance measuring equipment, when a correction instruction signal is supplied, a distance calculating circuit first drives an optically shielded light emitting element for correction to emit light, and produces a correction signal on the basis of a signal input into an adder connected to a light receiving element. Thereafter, the distance calculating circuit drives a light emitting element for measurement to emit light, and produces a distance measurement signal with referring the correction signal.

Abstract: Optical distance measurement apparatus and method. The apparatus comprises a light emitting circuit, a light receiving circuit, a trigger signal generation circuit, a pollution sensor, a diode abnormal state sensor, a control/time-distance conversion circuit, a cleaning device and a car collision prevention device. The pollution sensor receives a part of a light beam which is emitted from the light emitting circuit and then reflected from protecting glass mounted on a front side of the apparatus, to sense a variation in a reflectivity of the protecting glass, and discriminates a polluted state of the protecting glass in accordance with the sensed result.

Abstract: A laser range finder includes a circular in-sight field of view which incorporates within it a magnified "TV view" of the target area with the TV view roughly approximating the rectangular shape of a standard television picture. Also within the circular field, over and under the TV view, are a target quality indicator, a range distance display, and other indicators. Within the TV view is a targeting reticle which indicates roughly the footprint of ranging laser pulses such that a target can be selected. The target quality indicator is a bar graph which displays the number of identifiable received reflected laser pulses from a series of such pulses emitted by the range finder. By aiming the range finder at various targets via the footprint reticle, repeatedly firing the range finder and monitoring the target quality graph for each firing, a user can move the range finder to find a surface proximate the target with a reflective quality sufficient to yield an accurate target range reading.

Abstract: A device, and an associated method, for determining separation distances separating motor vehicles travelling along a roadway. A separation distance separating the motor vehicles is calculated responsive to targeting the vehicles with a laser range finder and determining the speeds of the vehicles. From this information, the separation distances separating the motor vehicles can be calculated. If the separation distance separating the motor vehicles is less than a minimum distance, then the calculated separation distance can be utilized by traffic enforcement officials to take appropriate enforcement actions.