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Confocal Pinhole
Notch Filter
In-focus scattered light
Pinhole Out-of-focus scattered light
Pinhole
Defocusing Technique
Laser Beam Microscope Confocal Probe
*
Objective Lens Z c
Focal Plane
Z 0
Sample
FIGURE 10.1 Schematic draft of the confocal probe confi guration and of the
probe/sample interaction.
probe selected xyz locations in the samples, with micrometer (lateral)
spatial resolution. Two-dimensional data maps were built up by xy
scanning the sample, and three-dimensional data sets were produced by
sequentially acquiring a set of xy slices at different z depths. A schematic
Confocal
Probe Depth Normal Probe PS Coefficient,
* *
-1
Materials z , lm Depth z , lm cm /GPa
c
c
Bony 4.5 28.3 2.95 ± 0.12
apatite (band at 960 cm )
−1
Alumina 4.1 30.2 −0.71 ± 0.06
−1
(band at 416 cm )
Tetragonal 4.2 23.5 −6.00 ± 0.15
−1
zirconia (band at 142 cm )
Monoclinic 3.3 10.0 −1.10 ± 0.16
−1
zirconia (band at 384 cm )
TABLE 10.1 Raman Probe and PS Coefficients for Various Biomaterials