Abstract: A rangefinder apparatus includes infrared light emitting diodes (IREDS) for projecting respective light beams toward a target object; and a position sensitive detector (PSD), disposed at a distance from the IREDS, having a light-detecting region for detecting respective reflected light beams of the light beams projected to the target object, the light-detecting region of the PSD being shaped substantially as a parallelogram with no rectangular corners. Since the light-detecting region of light-detecting means is shaped substantially as a parallelogram with no rectangular corners, the rangefinding accuracy can be improved while the manufacturing cost is restrained from increasing.

Abstract: The method and system are disclosed for reducing an optical surge in an optical data communication system that includes at least pair of optical lines, optical switches and optical amplifiers to maintain high reliability in data transmission. The optical surge is substantially reduced or suppressed by assuring a proper timing of the optical switch operation based upon a predetermined elapsed time or a predetermined safe amplification gain of the optical amplifier.

Abstract: Disclosed is an optical sensor used for remote laser level monitoring in liquid storage vessels. The sensor is mounted directly to a standard tank nipple, located on top of the vessel, by a threaded connecting means and is linked to a laser measurement device via fiber optic cabling. The level in the vessel is measured as a function of the time required for a laser signal to be transmitted from the sensor, reflected off the liquid surface and returned to the receiver lens located in the sensor.

Abstract: A laser beam transmitted from a laser diode is run for scanning laterally as a transmitted-beam elongated vertically with a lateral width thereof limited. A wave of the transmitted-beam reflected from an object is caught in a beam receiving area which is elongated laterally with a vertical width limited and scanned vertically, and is received by a photo-diode. Even if the vertical width of the transmitted-beam is set at a sufficient large value to absorb an error in the vertical mounting of a radar system, the period of time when the direct sun rays enter the beam receiving area to make the detection impossible can be shortened by vertically scanning the beam receiving area elongated laterally. Thus, the influence of the direct sun rays can be maintained to the minimum to reliably detect the object without need for a precise aiming, excluding the case where the height position of the sun corresponds to the level of the object.

Abstract: The present invention is a distance measuring device having a low power laser for use outdoors. The distance measuring device of the invention includes a laser emitting means that emits a pulsed laser beam to an object to be measured and an image reader that takes in irradiations images and stop period images of the object synchronously with an irradiation and stop period of the laser beam. A processing device then subtracts the stop image pixel values from the emission image pixel values to produce differential images. A minimum value image of the differential images is processed and binarized using a binary threshold to produce binary data from which a position where the laser beam is received is found. A calculation apparatus then determines a distance between the laser beam receiving position and the object based on the position where the laser beam is received.

Abstract: A distance measuring apparatus for measuring the distance to an object has a line of charge coupled device (CCD) elements which serve as two sensors for passive sensing and one sensor, in combination with a light emitting element, for active sensing. An infrared light cut-off filter is provided on the light receiving surface of all the elements while a visible light cut-off filter is provided on the light receiving surface of the elements corresponding to the active sensor. The light emitting element is provided with a pattern mask so that the object is irradiated with a pattern of light intensity. The active sensor detects the pattern and from this the position of the spectral center of the image can be determined to enable a distance value to be ascertained.

Abstract: A method for determining the relative motion of a surface with respect to a measurement device comprising: illuminating the surface from a source with incident illumination, such that illumination is reflected from portions of the surface toward a detector; spatially filtering the reflected illumination such that the phase of the detected optical illumination from a given scatterer on the surface is substantially constant or linearly related to the translation of the surface; generating a signal by the detector responsive to the illumination incident on the detector; and determining the relative motion of the surface from the signal.

Abstract: A laser telemeter having separate transmitting and receiving optical systems, and at least monocular target observation, in which a telescope optical system (5, 6) which is inserted before the transmitting optical system (2) and reduces the divergence of the transmitted beam, a telescope optical system (7, 8) which is inserted before the receiving optical system (3) and has an aperture angle adapted to the divergence of the transmitted beam and a common support frame (9) for the telescope optical systems (5, 6; 7, 8) which can be coupled at the front with the housing (10) of the laser telemeter (1) are provided.

Abstract: A distance judging system (S) includes at least two spaced apart marker devices (10) formed on a first object (12) and providing a signal (14). A viewer (A) is adapted to detect relative position of the signals (14) from the markers (10), and create an image (22) of the relative positions of the markers (10) within a field of view (16). A reticle (18) is superimposed on the field of view (16) of the viewer (A). The reticle (18) is selected to form a control area (20) within which simultaneous appearance of at least two images (22) of the markers (10) indicates that the first object (12) is at a distance (24) at least as great as a desired distance from the viewing apparatus (A); whereas, simultaneous appearance of less than two images (22) of the markers (10) within the control area (20) indicates that the first object (12) is at a distance (24) less than the desired distance.

Abstract: A range finding device of scanning type including a laser beam emitting means which emits pulse laser beams from a single light source while changing an emission angle and scanning, and a range finding means for detecting a range from an object from reciprocating times of the pulse laser beams reflected by the object, wherein the scan is conducted by shifting the pulse laser beams for each scan and the amount of shifting the beams is a value obtained by equally dividing an interval of the beams into a plural, whereby the range from the object can be measured at a high rate in many directions with a low cost, and an angular resolution in horizontal directions, an accuracy of relative position and an accuracy of relative velocity of the object are improved, and a time lag in judging a horizontal direction angle of the object can be minimized.

Abstract: A three-dimensional imaging system includes a two-dimensional array of pixel light sensing detectors and dedicated electronics and associated processing circuitry fabricated on a common IC using CMOS fabrication techniques. In one embodiment, each detector has an associated high speed counter that accumulates clock pulses in number directly proportional to time of flight (TOF) for a system-emitted pulse to reflect from an object point and be detected by a pixel detector focused upon that point. The TOF data provides a direct digital measure of distance from the particular pixel to a point on the object reflecting the emitted light pulse. In a second embodiment, the counters and high speed clock circuits are eliminated, and instead each pixel detector is provided with a charge accumulator and an electronic shutter.

Abstract: A sensor assembly for imaging passive infrared (IR) scenes and active laser radar (LADAR) scenes and for generating multi-dimension image data sets, and a method for same. A two-dimensional semiconductor imager sensitive to both passive IR radiation and active LADAR radiation when used in conjunction with subsequent signal processing creates a two-dimension passive image data set and a three-dimension active image data set with common x and y coordinates. The passive image data set is collected substantially proximate in time with the active image data set. The two image data sets are combined to form a multi-dimension image data set with the surface of three-dimensional objects indicating heat emission. The sensor assembly applies to burst illumination LADARs operating at a variety of wavelengths and passive IR detection in the middle wavelength IR (MWIR) or long wavelength IR (LWIR).

Abstract: The present invention provides a vibration measurement method and apparatus utilizing a self-mixing type laser Doppler vibrator meter. The vibration measurement method includes steps of: oscillating a laser beam of a predetermined wavelength and applying the laser beam to an object to be measured; mixing the reflected laser beam from the object and the oscillated laser beam for outputting a beat wave; calculating ratio of a beat wave amplitude for the turning point of the vibrating object, with respect to a predetermined reference amplitude; and calculating a displacement amount for the turning point of the vibrating object, according to the calculated ratio. This enables to detect the vibration of the object to be measured, with a high accuracy.

Abstract: In a distance measuring system in a camera including an integrating unit having an integrating capacitor, if the period of a second integration exceeds a maximum period, a CPU stops the second integration. Furthermore, the CPU informs a photographer that the distance measurement has not performed successfully by issuing an alarm, urging the photographer to take proper action. As the CPU determines the distance to the object to be measured based on the maximum period of the second integration, error in the distance measurement may be minimized.

Abstract: An in-line repeater implemented within a Wavelength Division Multiplexed (WDM) optical fiber communication system is shown that includes an attenuator. The communication system includes a WDM multiplexer that transmits a WDM signal including a series of WDM channels, via the in-line repeater, to a demultiplexer that separates the WDM channels into a series of output signals. Within the in-line repeater, the attenuator is coupled between two stages of a single amplifier in order to aid in the power equalization of the WDM channels at the demultiplexer. The addition of the attenuator results in the powers and OSNR of the individual WDM channels becoming closer in value, hence reducing the time and the dynamic range of transmitter power adjustments required for traditional methods to equalize the channels' powers.

Abstract: A multiple-axis inclinometer for measuring inclinations and changes in inclination comprises a cell which contains a liquid forming a horizon and which has a transparent base, and a device for illuminating a cross-line plate and imaging optics in the form of a piano-convex lens, which is arranged at the base of the cell or is a component part of the base, for imaging the cross-line plate on a receiver arrangement in the form of a CCD line. Two cross-line plates are provided, each having a cross-line grid formed of parallel cross-lines, wherein a light source is associated with each cross-line plate and illuminates the cross-line plate associated therewith. These two cross-line plates lie one above the other in an imaging plane which extends perpendicular to the surface of the liquid and in which the CCD line is also arranged, wherein the cross-lines of the two cross-line plates enclose an angle relative to one another whose bisector extends perpendicular to the imaging plane.

Abstract: An indicator for an optical instrument including an observational optical system to observe an image formed by an objective optical system having a focusing lens group, comprising a lens position detecting device to detect a position of the focusing lens group, a distance detecting device to obtain an object distance according to a position of the focusing lens group detected by the lens position detecting device, and a display device to display an object distance detected by the distance detecting device.

Abstract: An electromagnetic radiation detector system is disclosed which includes a detector of semiconductor material in the form of a superlattice having a plurality of layers of a first conductivity type spaced by alternate layers of a second conductivity type forming a layered structure having distinct natural energy band gap responsive to a narrow band of electromagnetic wavelengths, but which can be tuned by physical or electromagnetic devices to alter the band of wavelengths to which the detector responds. The system includes electrodes connecting the sensor to an output device.

Abstract: A radar apparatus for automotive vehicles is provided which is designed to emit laser beams to scan a forward zone for detecting moving object such as preceding vehicles and a downward zone for detecting lane marks printed on a road surface for defining a traffic lane. The downward zone is wider than the forward zone horizontally. Each zone has a minimum width required for assuring desired accuracy of radar detection of an object, thereby minimizing the number of emissions of the laser beams, resulting in an increase in lifetime of a laser diode and production of unwanted data on roadside objects having a low probability that the vehicle will collide them. The apparatus also includes a light focusing mechanism which focuses the laser beam on a given area in the downward zone to increase the power density of a return of the laser beam.

Abstract: In a distance measurement system, an integrating capacitor is preliminarily charged to at least a reference voltage VREF upon main power source power-on (a first predetermined period). When a shutter release button is half depressed to start a distance measurement (second predetermined period), the integrating capacitor is also preliminarily charged. At the end of the preliminarily charging in the first predetermined period, a drop in voltage occurs in the integrating capacitor due to dielectric absorption. However, by subsequently preliminarily charging at the start of the distance measurement (second predetermined period), a voltage drop in the integrating capacitor due to the dielectric absorption can be prevented. This second charging contributes to the prevention of error. Especially, if the first predetermined period is longer than the second one, the time required for the preliminarily charging at the start of the distance measurement can be further reduced.