Laserové skenování
3D záznam tvarů objektů dopadem laserového paprsku na předmět a detekce odraženého záření - intenzita a směr, složení obrazu z velkého počtu diskrétních bodů není to holografie!
nevýhody:
špatná identifikace hran
nutný speciální program na zpracování mračna bodů velmi drahé přístroje i software, které rychle stárnou
výhody:
bezdotyková profilometrie na vzdálenost cm - 100 km na vzduchu, ve vakuu i pod vodou rychlý sběr přímo měřených 3D bodů (tisíce až miliony| zcela automatizovaný provoz téměř konstantní přesnost se vzdáleností
Rozmítání paprsku ve 2 směrech x, y zrcadly
Charge-coupled device
Fixed mirror
Collecting lens
X-axis scanner
Fixed mirror
K-axis scanner
Polovodičové lasery VIS a IR 800-1500 nm; někdy kombinováno i více viditelných barev, odraz -úhel a intenzita, skenování 10-100 kHz, modulace 300-800 kHz
Bod abjcktu
Měřený objekt 7
jrdroj
Triangulační metoda, rozlišení zblízka: 50 um xy, 10 um z; z dálky LI DAR 1-20 bodů 25 cm na m2 z 1000 m.
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Měřený objekt
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Liniové skenování
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Fig. 2: The- scanner 3D Las been placed at a high 6 position to avoid the shade areas due to the presence of people. It surveys a 360: angle area.
Fig. 3: The Forum of Pompeii during the 3D
er
Fig. 4: "Cyclone"© software acquiring automatically a tie point (target).
Fig. E: Image in untrue colours of part of the 3D model, obtained by the super imposition of three scans.
Figure 12: Photograph of a planter statue of the Egyptian king (left) and the shaded image of the modelled result (right). The noise is broken.
Figure 13: Atrial of the nose restoration. Thr; (top left, top right and bottom left) are implanted from other reconstructed models and the last (bottom right) is restored by using repetitive depth-to-depth operators.
Figure 2 A background scan, top. and a derail ^caiL beloTY, of the area marked with a rectangle.
Figure 5. 3D reconstruction of a china knick-knack from a rotational scan On the right, a high resolution model, using reflectivity information to provide a photographic-like hyper realistic aspect. On the left, the same model in wireframe visualization mode after applying a severe decimation of the number of triangles to 10°of the initial value.
Figure 6. Left to right: A wooden object, its 3D image (intensity + phase), it* CAD model
Figure 7. 3D reconstruction of Emperor Constantino's marble- head (from Frascati Museum) seen from the bottom. The chosen visualization mode (point cloud) allows to see ako the back of the surface. Data where collected by the AM-LR from 3 different
points, of view at 120° along an axis.
Figure 1-2.
The medieval church of Radpuszta: side new and air view — a half-day project on site v/irh a few
days o f p o st-proc e s s mg
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Figure 4-5.
Detail of a Neolithic settlement at Balatonszarszo: air photo and the 3D laser scanning picture (to eliminate sliadow would be a very time consuming, arid therefore very expensive process).
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Figure 8. Relief shaded image with Im interval raster contours showing the topographic location ufthe Neolithic long harrows (yellow ujuam) around the dry valley system in the western part of the WHS, and the location of Bush Barrow {red arrow). Linear barrow cemeteries on ridgeltnes: Wtnterbourne Stoke (top left) and Norman ton Down (mainly to right of Blab Barrow).
GPS SaMit* Constellation
Figure 9. CASI j true and'false colour images showing lift- courrasr between the coniferous and leaflet deciduous mes (two colours) in Fargo Plantation, with the false colour image, generatedfrom, green, red and infrared hands emphasising the hare ioil of the narrow footpath across the Cursus at tlte eastern edre of the plantation.
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IFigure 1. Al-Khaiiieh facade. Petra Figure 2. Detailed view of the collected point;
cloud
part of Al-Khasneh
Figure 5. Tlie leít door of Al-Knasneh
Figure ó. Meshed, model for the left door
Figure 7. Two intersecting planar surfaces.
Figure 8.The distance image projected on the corresponding image.
Lidar - Light Detection And Ranging
Dálkový průzkum pomocí detekce odraženého/rozptýleného laserového nebo fluorescenčního záření, využití pružného rozptylu na aerosolech (Rayleigh / ~/\4), nepružného rozptylu (Raman / ~ v4, IR spektroskopie), doba rozptylu 10-10 - 10-12 s => vysoké prostorové rozlišení
Detekce země-vzduch nebo letadlo-vzduch/země/voda, družice-vzduch/země/voda Dálková analýza polutantů - analytický LID AR:
Kalibrace na 02, N2, C02; Př. Raman S02: N2 laser v noci LOD 1 ppm na 1 km, prostor, přesnost 10 m; fluorescence S02: 301,1 nm, LOD 0,1 ppb na 10m, 10 ppm na 1 km; N02, eten, bojové plyny: C02 laser
Skenovánípovrchu - archeologie, geolog, průzkum apod... měření vzdáleností: GaAs laser do 1 km, rozlišení 10 cm, Nd:YAG do 10 km, rozlišení 1 m, rubínový I. silné ns pulzy 1 GW, do 1000 km; měří se doba návratu i tvar odraženého pulzu
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od ráznost (%)
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0.4   Oč   0.3   1.0   1.2   1.4   1.6  1£  2.0   2.1 2.4 2.6
vlnová délka (pm)
Absorption of the Three Main Chromophores
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Figure 11. Absorption spectrum of the 3 main chromophores in tissues (water, haemoglobin and melanin)c. Arrows mark the
emission wavelengths of the main laser sources commercially available.
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1000 100 10
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Absorption coefficient of tissue (humana Aorta]
Absorption coefficient of water
0r1    0r2    0r4    0.8 1      2       4   6  S 10 Wavelength [urn] -►
Figure 10. Absorption coefficient as function of wavelength for water and tissues It can be seen that the tissue absorption is governed by the water content of the tissue for infrared wavelengths and the absorption characteristics of haemoglobin and other organic molecules in the visible and in the UV. Blood for instance has a strong absorption m the blue and green part of the spectrum, and penetration depth into the skin is largest for the red and near IR wavelengths.
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OIL SPILL
Konfokální mikroskopie -
prostorové skenování laserem buzené fluorescence, přeostřování do různých hloubek i horizontálních poloh
Emission filter
Detector (PMTJ Pinhole
Photomultiplier —í Detector
Laser Excitation Source
I
Focal Planes
— Detector Pinhole Aperture
Out-of-Focus Fluorescence Emission Light Rsy
Dichromatic Mirror
— Objective
Excitation Light Ray
Figure 2. Schematic diagram of the optical pathway and principal components in a laser scanning confocal microscope.
Beam expander
Background
Laser
Microscope objective
Focal plane
Detection volume
Fig. 2 Beatn path in a confocal LSivi. A microscope objective is used to focus a laser beam onto the specimen, where it excites fluorescence, for example. The fluorescent radiation is collected by the objective and efficiently directed onto the detector via a dichroic beamsplitter. The interesting wavelength range of the fluorescence spectrum is selected by an emission filter, which also acts as a barrier blocking the excitation laser line, The pinhole is arranged in front of the detector, on a plane conjugate to the focal plane of the objective. Light coming from planes abow or below the focal plane is out of focus when it hits the pinhole, so most of it cannot pan the pinhole and therefore does not contribute to forming the image.