Structured Light vs LiDAR
Structured light projects a pattern and reads its distortion; LiDAR times a laser pulse. One is built for detail at arm's length, the other for range across a scene.
Both work in darkness, both need no targets, and at a forensic scene they do different jobs.
No sensitive case details required.
Structured light or LiDAR for forensics?
Structured light for evidence, bodies and marks at up to 0.05 mm, from arm's length. LiDAR for the scene as a whole at millimetre accuracy over tens of metres. Both work in darkness; neither replaces the other.
How they compare
The comparison that matters is not which is better, but which does which job.
| Structured light — handheld, close range (Spider II, Leo, Eva)Projected pattern, read by cameras. | Laser / LiDAR — tripod, long range (Ray II)Laser pulse timed to each point. | |
|---|---|---|
| How it measures | Pattern distortion across the surface | Time of flight of a laser pulse |
| Best accuracy | Up to 0.05 mm (Spider II) | 1.9 mm at 10 m |
| Working distance | Arm's length | 0.5–130 m |
| Colour | Full colour texture with the geometry | Colour from onboard cameras |
| Lighting needed | None — it brings its own light | None — laser is self-illuminating |
| Choose this when | Evidence, bodies, wounds, marks, vehicles: anything you can walk up to. | Rooms, buildings, roads, outdoor scenes: anything you measure from a distance. |
Two ways of measuring, and why both work in the dark
A structured-light scanner projects a known pattern onto a surface and watches how it deforms across cameras a known distance apart. Geometry is triangulated from that deformation, at very high density and very close range. Artec Spider II reaches 0.05 mm accuracy this way; Leo and Eva trade some resolution for speed over bodies and vehicles. All three capture colour texture with the geometry.
A laser scanner times a pulse to each point in a dome around itself. Accuracy is millimetres over tens of metres — Artec Ray II states 1.9 mm at 10 metres — and range is what it is for: a full room, a building, a road. Neither technology depends on ambient light, which is why both work at a night scene or in a burnt-out interior.
At a forensic scene they are complementary. The laser scanner records the room; the structured-light scanner records what is in it. Artec Studio registers one into the other. Smartphone "LiDAR" is a different, centimetre-class sensor, compared separately under professional scanner vs smartphone LiDAR.
See structured light and LiDAR on the same scene, lights on and lights off — book a demo.
Book a demoQuestions practitioners ask
Does structured light work in daylight?
Yes. Artec handheld scanners work indoors and outdoors; very bright direct sun on a surface can reduce capture quality, as with any optical method.
Does either need targets?
No. Both Artec structured-light scanners and Ray II track by geometry; targets are optional aids, not requirements.
Is blue structured light different from white?
Spider II uses blue structured light, which is less affected by ambient light and surface colour and gives finer resolution on small detail.
Which captures colour?
Both. Handheld scanners capture colour texture with each frame; Ray II records colour with onboard cameras.
Tell us about the work you do
A forensic application specialist will come back with the device that fits it, the accuracy to expect at that scale, and how the data reaches your existing workflow.