Abstract: Surveying apparatus such as, for example, a video theodolite or video tachymeter, is disclosed. In some embodiments, the surveying apparatus may include a base, a support pivotable about a first axis relative to the base, a targeting unit pivotable about a second axis relative to the support and comprising a telescope optical unit comprising at least one objective and a motorized-adjustable focusing optical unit and also an eyepiece and/or a camera chip for recording an image through the objective, goniometers for measuring pivoting positions of the support and the targeting unit, an electro-optical distance measuring device, an evaluation and control unit, which provides a calibrated autofocusing functionality for automatically setting the focusing optical unit in a manner dependent on a target distance measured by the distance measuring device and contains for this stored calibration coefficients with regard to focusing optical unit positions to be set in a target-distance-dependent manner.

Abstract: A method and system are described for illuminating a target with a laser source with a wide-area illuminating beam. A conjugator can receive a reflected, imprinted wavefront from the target that is imprinted with effects from beam distortions and obstructions between the laser source and the target. The conjugator can then generate a hologram. A directed laser beam can then be generated to the target by reading the generated hologram with a second reference beam creating a time-reversed wavefront that can be generated with high gain. The time-reversed wavefront can retrace the path that originated from the laser source to the target, and can reverse the effects of beam distortions and obstructions. Finally, an enhanced return can be received from the target with a receiver, and a time-gating switch can be utilized that selectively selects a particular range of return wavefronts that include wavefronts that reached the target.

Abstract: A marine sonar display device comprises a display, a sonar element, a multi axis sensor, a memory element, and a processing element. The display presents sonar images. The sonar element generates a sonar beam. The multi axis sensor determines an orientation and a tilt of the sonar element and present a sensor signal indicating the orientation and the tilt. The processing element is in communication with the display, the sonar element, the multi axis sensor, and the memory element. The processing element further determines an operating mode of the marine sonar display device, wherein the operating mode varying according to the orientation and the tilt of the sonar element.

Abstract: A method for towing marine geophysical sensor streamers in a body of water includes moving a towing vessel at a selected speed along the surface of the body of water. At least one geophysical sensor streamer is towed by the vessel at a selected depth in the water. A velocity of the streamer in the water is measured at at least one position along the streamer. The selected speed of the towing vessel is adjusted if the measured velocity is outside of a selected range.

Abstract: A programmable current source for use with a time of flight pixel cell includes a first transistor. A current through the first transistor is responsive to a gate-source voltage of the first transistor. A current control circuit is coupled to the first transistor and coupled to a reference current source to selectively couple a reference current of the reference current source through the first transistor during a sample operation. A sample and hold circuit is coupled to the first transistor to sample a gate-source voltage of the first transistor during the sample operation. The sample and hold circuit is coupled to hold the gate-source voltage during a hold operation after the sample operation substantially equal to the gate-source voltage during the sample operation. A hold current through the first transistor during the hold operation is substantially equal to the reference current.

Abstract: Systems and methods for identifying and locating target objects based on echo signature characteristics are disclosed. According to an aspect, a system includes a transmitter configured to transmit one or more mechanical waves to a target object for echo of the one or more mechanical waves by the target at a predetermined signature characteristic. The system also includes a detector configured to detect the echo. Further, the system includes a computing device configured to identify the predetermined signature characteristic of the detected echo for locating the target object.

Abstract: Disclosed systems and methods provide enhanced seismic images through the use of partial image stacking weights that are based on the resemblance between the local partial image and a reference image. At least some method embodiments include obtaining partial images of a survey region and stacking the partial images to produce a reference image. The partial images are then recombined to form an enhanced image, wherein the recombining includes: measuring at each point the reference image's similitude with each of the partial images; and determining at each point an enhanced image value from a weighted combination of corresponding values in the partial images, the weighted combination using weights derived from the reference images' similitude at that point to each partial image.

Abstract: A method is provided that involves mounting a transmit block and a receive block in a LIDAR device to provide a relative position between the transmit block and the receive block. The method also involves locating a camera at a given position at which the camera can image light beams emitted by the transmit block and can image the receive block. The method also involves obtaining, using the camera, a first image indicative of light source positions of one or more light sources in the transmit block and a second image indicative of detector positions of one or more detectors in the receive block. The method also involves determining at least one offset based on the first image and the second image. The method also involves adjusting the relative position between the transmit block and the receive block based at least in part on the at least one offset.

Abstract: Reflective assemblies are provided that may be attached to the end of a chromatic confocal point sensor optical pen. Each reflective assembly includes a reflective surface (e.g., a turning mirror) oriented for directing a measurement beam along a measurement axis at a selected angle relative to the central Z-axis of the optical pen. Reflective assemblies with different orientations for the measurement beams (e.g., 60 degrees, 120 degrees, etc.) allow for measurements of workpiece features that cannot be achieved with a measurement beam directed in a normal incident manner or at a standard 90 degree orientation. In one implementation, the reflective assemblies may be kinematically located and retained using magnetic coupling, and may be rotated and reseated in different rotational orientations about the central Z-axis of the optical pen. A set of such reflective assemblies greatly increases the measurement capability of a single optical pen, in an economical manner.

Abstract: An acoustic sensing system and method includes at least one cluster of acoustic sensors in communication with a computing device. The computing device is configured to process received acoustic signals, and provide at least one of detection of the acoustic source presence; determination of direction of arrival of an acoustic wave emitted by an acoustic source; and classification of the acoustic source as to its nature. The cluster may include at least two sensors and the computing device may be configured to process the received acoustic signals and provide localization of the acoustic source in three dimensions. The cluster of acoustic sensors may comprise at least one seismic wave sensor.

Abstract: An acoustic reflector comprises a shell surrounding a solid elastomeric core free of joints. The shell transmits acoustic waves incident on the surface of the shell partially into the core to be focused and reflected from an area of the shell located opposite to the area of incidence so as to provide a reflected acoustic signal output from the reflectorpartially around the circumference of the shell and to combine constructively with the reflected acoustic signal output. The ratio of the speed of sound wave transmission in the shell to the average speed of the wave transmission in the core is preferably in the range of 2.74 to 3.4 best results being in the range of 2.74 to 2.86 inclusive.

Abstract: Mapping apparatus includes a transmitter, which emits a beam comprising pulses of light, and a scanner, which is configured to scan the beam, within a predefined scan range, over a scene. A receiver receives the light reflected from the scene and to generate an output indicative of a time of flight of the pulses to and from points in the scene. A processor is coupled to control the scanner so as to cause the beam to scan over a selected window within the scan range and to process the output of the receiver so as to generate a 3D map of a part of the scene that is within the selected window.

Abstract: A nonlinear dynamic focusing control method includes: (1) using a minimum length in a scan line having the minimum length and a maximum length as an initial location and assigning a focal point on the scan line; (2) calculating half depth of focus of the focal point, and the initial location plus the half depth of focus of the focal point being the location of this focal point on the scan line; (3) determining an initial calculation location of the next focal point by adding the half depth of focus of the focal point from the location of this focal point on the scan line in the direction of the maximum length; and (4) determining if the initial calculation location of the next focal point is greater than the maximum length.

Abstract: The invention relates to a laser beam horizontal trueness testing device for a laser beam projection device for construction and/or interior design work. The laser beam projection device is equipped with a beam self-leveling functionality. The laser beam horizontal trueness testing device has a telescope with an attenuating filter, a magnifying objective, and a flat image sensor for capturing an image of a laser beam incident on the objective. Components of the laser beam horizontal trueness testing device further include a natural inclination compensator and an analyzing unit which is designed to automatically ascertain an image position of the laser beam captured in the image by processing the image. According to the invention, the flat image sensor is arranged on an image plane of the objective, and the analyzing unit is additionally designed to quantify the laser beam horizontal trueness.

Abstract: A camera for determining distances to a scene, the camera comprising: a light source comprising a VCSEL controllable to illuminate the scene with a train of pulses of light having a characteristic spectrum; a photosurface; optics for imaging light reflected from the light pulses by the scene on the photosurface; and a shutter operable to gate the photosurface selectively on and off for light in the spectrum.

Abstract: Laser radar systems include a pentaprism configured to scan a measurement beam with respect to a target surface. A focusing optical assembly includes a corner cube that is used to adjust measurement beam focus. Target distance is estimated based on heterodyne frequencies between a return beam and a local oscillator beam. The local oscillator beam is configured to propagate to and from the focusing optical assembly before mixing with the return beam. In some examples, heterodyne frequencies are calibrated with respect to target distance using a Fabry-Perot interferometer having mirrors fixed to a lithium aluminosilicate glass-ceramic tube.

Abstract: The disclosure relates to a measuring apparatus, in particular a handheld measuring apparatus, for measuring a target object in a multidimensional manner, wherein the distance to individual object points of the target object is sequentially measured, in particular using a phase-measuring system, which apparatus has at least: a transmitting device for emitting optical measuring radiation towards the target object; a receiving device having a detection area for detecting optical measuring radiation returning from the target object; a scanning system for deflecting the optical measuring radiation, and an evaluation device for determining measured distance values. The detection area of the receiving device has a plurality of pixels, wherein each pixel has at least one SPAD, and wherein each of the plurality of pixels is connected to the evaluation device. The disclosure also relates to a measuring device having such a measuring apparatus.

Abstract: A method for estimating a position of a first acoustic linear antenna relative to a second acoustic linear antenna belonging to a network of towed acoustic linear antennas on which are arranged a plurality of nodes. The method includes: setting a first plurality of nodes arranged on the first antenna to act as sender nodes and a second plurality of nodes arranged on the second antenna to act as receiver nodes; forming a first group of sender nodes each sending a same first acoustic signature; for each receiver node: obtaining a propagation duration and establishing a geometrical figure representative of potential positions of a sender node, based on the propagation duration and the first acoustic signature; determining a set of common points between the geometrical figures; estimating the position of the first antenna relative to the second antenna based on the set of common points.

Abstract: Disclosed herein are a beamforming method, a method of determining a beamforming coefficient, and an ultrasonic imaging apparatus.

Abstract: An apparatus and method for removing noise of an ultrasonic system to improve robustness against noise by removing external noise from a reception signal reflected from an object are provided. The method includes transmitting, by a sensor, a transmission signal to a medium and receiving a reception signal reflected from the medium. A controller is configured to remove noise from a frequency range recognized as a normal signal from the reception signal and calculate a correlation between the transmission signal and a signal in the frequency range recognized as the normal signal in the reception signal. In addition, the controller is configured to determine whether the signal in the frequency range recognized as the normal signal is the normal signal or noise based on the calculated correlation.