Glossary

LAS (Log ASCII Standard) is an open-source file format designed to store and exchange three-dimensional point cloud data acquired from LIDAR scanning systems.

LAS (Log ASCII Standard) is an open-source file format designed to store and exchange 3D point cloud data from LiDAR surveys and other surveying instruments in a standardized, vendor-neutral manner.

A surveying instrument that uses laser light to measure distances between points by calculating the time it takes for light to reflect off a target and return to the device.

LAZ is a lossless compression format for point cloud data that reduces file size while preserving all surveying and spatial information without data loss.

A mathematical method used in surveying to process redundant measurements and minimize errors, producing the most probable values for survey coordinates and observations.

A precise written identification of a parcel of land using standardized surveying methods and references to establish its exact boundaries and location for legal and property ownership purposes.

Leica Cyclone is a comprehensive point cloud processing and visualization software suite developed by Leica Geosystems for analyzing, managing, and converting three-dimensional survey data from laser scanners and other surveying instruments.

Leica Infinity is a comprehensive office software platform designed for processing, analyzing, and managing surveying data collected from Leica instruments and external sources.

Leveling is a surveying technique used to determine elevation differences and establish vertical control by measuring the vertical distance between points using an optical or digital level instrument.

LiDAR is a remote sensing technology that uses laser pulses to measure distances and create detailed three-dimensional maps of terrain and objects.

LiDAR intensity refers to the strength or amplitude of the laser signal reflected back from surveyed surfaces, providing additional information about material properties and surface characteristics beyond distance measurements.

A coordinate system established at a specific project location using arbitrary or project-defined origins and axes rather than national geodetic references.

Level of Development (LOD) is a standardized specification for the detail, accuracy, and reliability of information contained in Building Information Models at each project phase.

A longitudinal profile is a two-dimensional graphical representation of ground elevation along a surveyed line or route, showing vertical changes relative to horizontal distance.

A surveying technique that provides precise elevation and positioning data to automated construction machinery for real-time grade and alignment control during earthwork operations.

A mathematical method of representing the three-dimensional Earth's curved surface on a two-dimensional flat map or coordinate system.

Map scale is the ratio between distances on a map and their corresponding distances on the Earth's surface, expressed as a fraction, ratio, or graphic representation.

Marine survey is the systematic measurement and mapping of underwater and coastal features, including seabed bathymetry, obstructions, and maritime boundaries for navigation, construction, and resource management.

Mean Sea Level (MSL) is the average height of the sea surface across all tidal cycles, used as the primary vertical reference datum for surveying and elevation measurements worldwide.

A specialized surveying process that captures precise three-dimensional coordinates and spatial data of mechanical, electrical, and plumbing systems to integrate into Building Information Models.

A cylindrical map projection that represents the Earth's surface with constant bearing lines (rhumb lines) appearing as straight lines, widely used in marine navigation and modern web mapping applications.

A method of describing land boundaries using natural and artificial landmarks, distances, and directions rather than coordinates or geometric shapes.

Mean High Water (MHW) is the average elevation of the highest daily tidal level recorded over a 19-year National Tidal Datum Epoch, serving as a critical reference datum for coastal surveys and property boundary determination.

MicroSurvey FieldGenius is a comprehensive field data collection and surveying software platform designed for surveying professionals using total stations, GNSS receivers, and other surveying instruments.

A compact optical reflector used with total stations and laser theodolites to measure distances and establish precise positioning in surveying operations.

Mean Lower Low Water (MLLW) is the average elevation of the lowest tides occurring during a 19-year tidal cycle, serving as the primary vertical reference datum for coastal and marine surveying operations.

A mobile mapping system is an integrated platform combining GNSS, IMU, and imaging sensors mounted on vehicles to rapidly collect geospatial data for surveying and mapping applications.

An acoustic survey instrument that emits multiple sonar beams simultaneously to map seafloor bathymetry and create detailed three-dimensional underwater topographic data.

A systematic calibration procedure that verifies and corrects the geometric relationships between a multibeam sonar system and its vessel's reference frame to ensure accurate seafloor mapping.

Multibeam sonar is a hydrographic surveying technology that emits multiple acoustic beams simultaneously to create detailed bathymetric maps of underwater terrain.

Multipath error mitigation refers to techniques and technologies used to reduce signal reflections and their distortive effects on surveying measurements in GNSS and other positioning systems.

Multi-View Stereo (MVS) is a 3D reconstruction technique that uses multiple overlapping photographs from different viewpoints to create dense point clouds and detailed 3D models for surveying and mapping applications.

NAD83 (North American Datum of 1983) is the primary geodetic reference system used for mapping and surveying in North America, defining the precise coordinate framework for all spatial data.

Nadir aerial imagery is vertical aerial photography captured directly downward from an aircraft or drone, perpendicular to the Earth's surface, used in surveying for orthophoto generation and spatial analysis.

The nadir point is the location on Earth's surface directly below a satellite, aircraft, or survey instrument, representing the perpendicular intersection with the ground plane.

A standardized system of geographic reference coordinates used by surveying and mapping authorities to establish precise positions across a nation's territory.

A specialized surveying and BIM coordination process using Autodesk Navisworks software to detect spatial conflicts, clashes, and coordination issues between design disciplines before construction execution.

Normal Distribution Transform (NDT) is a probabilistic point cloud registration algorithm used in surveying and mapping to align 3D laser scan data with high precision and speed.

NDVI is a standardized mathematical index calculated from multispectral satellite or aerial imagery to quantify vegetation health and density across surveyed landscapes.

Network adjustment is the mathematical process of distributing measurement errors across surveying observations to achieve the most probable positions of surveyed points in a network.

The NSRS is the official framework of geographic coordinates and elevations maintained by NOAA that provides the authoritative reference system for all surveying, mapping, and positioning activities in the United States.

NTRIP (Networked Transport of RTCM via Internet Protocol) is an open-source protocol for streaming real-time GNSS correction data over the internet to enable centimeter-level positioning accuracy.

Oblique aerial imagery is remotely sensed photographic data captured from aircraft or drones at oblique angles to the Earth's surface, providing three-dimensional perspective views of terrain and built environments.

Offshore survey is the process of measuring, mapping, and documenting underwater and coastal features, bathymetry, and infrastructure in marine environments beyond the shoreline.

An optical plummet is a precision sighting device integrated into surveying instruments that aligns the instrument's vertical axis directly above a ground point using magnified crosshairs and a mirror system.

Orthometric height is the vertical distance from a point on Earth's surface to the geoid, measured along the direction of gravity.

The process of creating a geometrically corrected, seamless mosaic image from overlapping aerial photographs or drone imagery by removing perspective distortion and aligning images to a common coordinate system.

An orthophoto is a geometrically corrected aerial or satellite photograph that has been adjusted to remove distortions caused by camera tilt and terrain relief, allowing it to be used as an accurate map.

A professional land survey that determines and documents the precise legal boundaries of a property parcel using field measurements and existing records.

A dimensionless geometric factor that quantifies how satellite geometry affects the accuracy of horizontal and vertical position measurements in GNSS surveying.