Get in touch with QJKH Company
3D LiDAR Sensors Explained: Technology, Scan Types, and How to Choose
01 · LiDAR Technology Guide
What Is a 3D LiDAR Sensor?
A 3D LiDAR sensor measures distance across multiple horizontal and vertical directions to create a three-dimensional point cloud. This allows robots, vehicles and automation systems to perceive spatial geometry that cannot be represented by a single horizontal scan plane.
LiDAR — Light Detection and Ranging — is an active optical sensing technology. Because the sensor supplies its own optical illumination, it does not depend on visible scene lighting in the same way as a passive camera. Measurement performance can still be influenced by sunlight, target reflectivity, weather, surface angle and sensor design.
CCH Product Scope
CCH currently focuses its international LiDAR offering on industrial 2D LiDAR. 3D LiDAR is covered in this article as an educational technology topic rather than a currently offered CCH product line.
3D Point-Cloud Concept
Conceptual illustration. Real point-cloud density and coverage depend
on sensor architecture, field of view and scanning method.
02 Measurement Principle
How 3D LiDAR Works: From Laser Measurement to Point Cloud
A 3D LiDAR repeatedly measures distance in many horizontal and vertical directions. Each measurement is associated with its scan direction, allowing the sensor or downstream software to build a spatial representation of the surrounding environment.
01
Emit Light
Optical energy is directed toward selected parts of the surrounding scene.
02
Reflect From a Target
Part of the emitted energy is reflected by objects and surfaces in the environment.
03
Measure the Return
The receiver detects returned light and the ranging system derives information related to target distance.
04
Combine Distance & Direction
Distance measurements are associated with corresponding horizontal and vertical scan directions.
05
Create the Point Cloud
Repeated measurements produce spatial points that describe the geometry surrounding the sensor.
Common Ranging Principle
Time-of-Flight (ToF) LiDAR
Many LiDAR systems use Time-of-Flight measurement, where distance is derived from the travel time of emitted light and its detected return. Other LiDAR designs may use different optical ranging principles, so the underlying measurement method should be checked for the specific sensor being evaluated.
Working Range
Depends on sensor design, target reflectivity, target size,
incidence angle and environmental conditions.
Angular Resolution
Describes the angular spacing between measurements in horizontal and
vertical directions.
Point Rate
Describes measurement throughput, but does not by itself determine
point-cloud quality or application performance.
Frame / Scan Rate
Influences how frequently the surrounding geometry is refreshed as
the sensor, robot or environment moves.
Range, angular resolution, scan pattern, point distribution, update rate,
target properties, environment and software processing should be
evaluated together rather than relying on one headline specification.
03 Scanning Architectures
3D LiDAR Types: Mechanical, MEMS, Flash & OPA
“3D LiDAR” describes a type of spatial measurement output rather than one single hardware architecture. Different technologies steer or distribute optical energy in different ways, creating different field- of-view, packaging, scan-pattern and performance characteristics.
Mechanical LiDAR
Mechanical 3D LiDAR uses rotating or moving assemblies to sweep measurements through the surrounding environment.
- Can provide wide horizontal coverage
- Well-established scanning architecture
- Includes moving mechanical components
MEMS LiDAR
MEMS LiDAR uses microscopic moving mirrors to steer the beam through a defined field of view without rotating the complete sensor housing.
- Compact directional scanning
- Field of view depends strongly on implementation
- Useful where package size is important
Flash LiDAR
Flash LiDAR illuminates a wider scene and measures depth across an imaging receiver rather than mechanically scanning each direction in sequence.
- No conventional scanning mechanism required
- Can support compact solid-state designs
- Range, power and ambient-light trade-offs vary by design
OPA LiDAR
Optical phased-array LiDAR steers optical energy electronically by controlling the phase relationship between multiple emitting elements.
- No macroscopic mechanical steering mechanism
- Potential for highly integrated sensor designs
- Performance and commercial maturity vary by implementation
What Does “Solid-State LiDAR” Mean?
The term solid-state LiDAR is used for a family of architectures that
reduce or eliminate conventional rotating scanner assemblies. MEMS,
Flash and OPA technologies may all appear in discussions of solid-state
LiDAR, but they use different sensing and beam-steering approaches.
What About Non-Repetitive Scanning?
Non-repetitive scanning describes how measurement points are distributed
over time rather than one single LiDAR hardware architecture. In systems
using non-repeating scan patterns, accumulated coverage can become denser
as more measurements are collected. Whether this is beneficial depends on
motion, integration time, object geometry and the downstream perception
algorithm.
04 Technology Comparison
2D LiDAR vs 3D LiDAR: Which One Fits the Application?
3D LiDAR is not automatically an upgrade from 2D LiDAR. The better choice depends on whether the application requires a horizontal scan plane or true volumetric information.
Requirement
2D LiDAR
3D LiDAR
Horizontal scan plane
Strong fit
Can provide more information than required
Vertical geometry
Limited to the scan plane
Available through multi-height measurements
Data complexity
Lower
Higher
Processing requirement
Generally lower
Generally higher
Volumetric perception
No, from a single scan plane
Yes
Mapping & localization
Common where planar geometry is sufficient
Useful where 3D structure matters
When 2D LiDAR May Be the Better Fit
Horizontal ranging, AGV localization, object positioning, industrial detection and many automation tasks can often be handled with a simpler 2D scan plane.
Explore CCH Industrial 2D LiDAR →When 3D LiDAR Adds Useful Information
If obstacle height, overhanging structures, vertical geometry or volumetric mapping are important, a 3D point cloud can provide information unavailable from a single horizontal plane.
05 Functional Difference
3D LiDAR vs Safety Laser Scanner
Industrial LiDAR and safety laser scanners may use related ranging principles, but they serve different system functions. A perception sensor should not be assumed to provide a certified safety function.
Automation Data
Industrial 2D LiDAR
Provides horizontal distance and scan information for automation, ranging, localization, positioning and detection tasks.
- Horizontal scan plane
- Navigation / localization
- Object positioning
- Industrial ranging
Volumetric Perception
3D LiDAR
Generates three-dimensional point-cloud data for mapping, perception and applications where vertical geometry is important.
- 3D point clouds
- Volumetric mapping
- Multi-height obstacle information
- Robotic perception
Safety Function
Safety Laser Scanner
Designed and certified for safety-related area monitoring when used within an appropriate machine or mobile-robot safety system.
- Protective fields
- Warning fields
- Safety-related outputs
- Personnel protection
A standard 2D or 3D perception LiDAR should not be treated as a safety
laser scanner unless the specific device and function have the required
functional-safety certification.
06 Industrial Applications
Where 3D LiDAR Makes Sense in Industrial Automation
3D LiDAR becomes particularly useful when the application needs information about height, overhanging objects, vertical geometry or complete three-dimensional structure.
01
AGV / AMR Perception & SLAM
3D point-cloud data can support mapping and localization in environments where vertical structures, racks, overhangs or multi-level geometry contribute useful localization features.
02
3D Mapping & Surveying
Dense spatial measurements can be used to create three-dimensional models of industrial spaces, structures and other environments.
03
Multi-Height Obstacle Detection
A 3D sensor can provide information about objects above or below a single horizontal scan plane, including overhanging structures or objects with significant vertical shape.
04
Robotic & Autonomous Perception
Mobile robots and autonomous systems can combine 3D LiDAR with cameras, IMUs, odometry and perception software to understand complex surroundings.
3D LiDAR does not perform classification, mapping or navigation by itself.
Those functions normally depend on downstream software, algorithms and,
in many systems, additional sensors.
07 Selection Factors
How to Evaluate a 3D LiDAR Sensor
A useful 3D LiDAR comparison looks beyond maximum range or total point rate. Evaluate the specifications that affect the real scene, mounting position, target properties, environment and software architecture.
01
Working Range
Check the conditions behind the published range, including target reflectivity, target size, incidence angle and ambient conditions.
02
Accuracy & Repeatability
Accuracy describes closeness to the actual distance, while repeatability describes consistency across repeated measurements.
03
Angular Resolution
Required angular resolution depends on object size, working distance and the level of spatial detail needed by the application.
04
Field of View
Do not assume every 3D LiDAR provides 360° coverage. Horizontal and vertical field of view vary significantly between architectures.
05
Environment & IP Rating
Consider temperature, dust, water, sunlight, fog, rain and optical- window contamination. Check the actual enclosure and IP rating specified for the sensor.
06
Interface & Software
Evaluate Ethernet communication, timestamps, synchronization, SDK availability and ROS or ROS 2 compatibility when these are relevant to the project.
07
Wavelength & Laser Safety
LiDAR systems may operate at wavelengths such as 905 nm or 1550 nm. Wavelength influences optical design and detector selection, but should not be treated as a standalone indicator of overall performance.
08
Scan Pattern & Return Data
Compare repetitive or non-repetitive point distribution and whether the sensor provides single-return, multiple-return or other echo information needed by the perception algorithm.
905 nm · 1550 nm · Laser Classification
Wavelength Is Only One Part of the Design
Both 905 nm and 1550 nm wavelengths are used in LiDAR systems. Differences in emitters, detectors, optics, power, target response and system architecture mean wavelength alone does not determine usable range or measurement quality.
For any sensor, verify the manufacturer’s laser-safety classification and the applicable IEC 60825-1 documentation. Where a product is specified as Class 1, confirm that classification from the actual product documentation rather than assuming it from wavelength alone.
Point Distribution · Echo / Return Information
More Points or More Echoes Are Not Automatically Better
Scan pattern determines where measurements appear over time. Non-repetitive scanning can distribute points differently from a repeating scan pattern, while multi-return or multi-echo information may provide additional information from complex optical scenes.
The useful configuration depends on the application, target geometry, environmental conditions, update time and how the downstream perception software processes the returned data.
Evaluate specifications under the conditions that matter to the application.
Two 3D LiDAR sensors with similar headline range or point-rate numbers can behave very differently when field of view, wavelength, scan pattern, reflectivity, environmental conditions, return data and software integration are considered together.
08 Limitations & FAQ
3D LiDAR Limitations & Common Questions
LiDAR is an active optical technology, but measurement performance still depends on the environment, target surface and sensing architecture.
Rain, Fog & Snow
Water droplets and airborne particles can reduce effective range or introduce additional returns.
Sunlight
Strong ambient optical energy can affect signal-to-noise performance, depending on sensor design.
Target Reflectivity
Dark, reflective or highly angled surfaces can produce different measurement behaviour.
Processing Load
Dense 3D point clouds require more network bandwidth, processing and software than a simple 2D scan.
What is a 3D LiDAR sensor?
A 3D LiDAR measures distance across multiple horizontal and vertical directions and combines those measurements into a three-dimensional point cloud representing surrounding geometry.
Can 3D LiDAR work in complete darkness?
Yes. LiDAR provides its own optical illumination and therefore does not require visible scene lighting in the same way as a passive camera. However, performance can still be affected by environmental conditions and target properties.
What is point-cloud data?
A point cloud is a collection of spatial measurement points, typically represented by X, Y and Z coordinates and sometimes additional information such as return intensity.
What is the difference between 2D LiDAR and 3D LiDAR?
A 2D LiDAR normally measures within a horizontal scan plane, while a 3D LiDAR also captures vertical information. 2D sensing is often sufficient for planar ranging and localization, while 3D sensing is useful when volumetric geometry matters.
Does 3D LiDAR replace a safety laser scanner?
Not automatically. A perception LiDAR should not be treated as a safety device unless the specific product and function have the required functional-safety certification. Safety laser scanners are designed specifically for safety-related area monitoring.
What affects 3D LiDAR range?
Range depends on factors including sensor architecture, target reflectivity, target size, incidence angle, sunlight, weather, contamination and the measurement threshold used by the sensor.
Mechanical vs solid-state LiDAR: what is the difference?
Mechanical LiDAR uses moving scanning assemblies, while solid-state approaches reduce or eliminate conventional rotating mechanisms. MEMS, Flash and OPA are different technologies that may be discussed within the broader solid-state category.
How many points per second does a 3D LiDAR need?
There is no universal point-rate requirement. The necessary density depends on object size, working distance, field of view, angular resolution, vehicle speed and the perception or mapping algorithm.
How much does a 3D LiDAR cost?
Pricing varies widely with architecture, range, field of view, environmental rating, production volume, software support and measurement performance. For industrial projects, total integration cost is often more meaningful than sensor price alone.
What is the difference between 3D LiDAR and 4D LiDAR?
“4D LiDAR” is commonly used for systems that combine 3D spatial measurements with additional motion-related information such as radial velocity. The exact meaning can vary between manufacturers.
Choose the Right Sensing Approach
Need LiDAR for an AGV or Industrial Automation Project?
If your application can be solved with horizontal ranging, localization or industrial detection, explore CCH industrial 2D LiDAR. For safety-related mobile-robot protection, review the SH27 safety laser scanner range.