SLO 2016

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Jan Tomáštík
Joint Laboratory of Optics of Palacky University and Institute of Physics of the
Academy of Sciences of the Czech Republic
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Optical microscope
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Confocal microscope
Telescope
(one particular)
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SLO 2016
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A complex optical instrument that increases the
viewing angle of the eye, and thus improves its
resolution.
Multiple optical systems: Ocular and objective
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Objective – system of lens, that is near to the observed object.
Object is placed close the objective focal plane and objective
creates its real, inverted and magnified image (placed between
ocular an its focal point. Objective magnification ranges from x5 to
x100
Ocular – behaves as a loupe that further magnifies the image from
objective. Unreal, inverted and magnified image is created. Ocular
magnification ranges from x5 to x20.
Overall magnification is calculated by multiplying both individual
magnifications. Typical maximum of optical microscope is up to
x1000.
Depth of field – Area of focus defined in the z-axis
(depth). It decreases with increasing magnification.

Out-of-focus areas are part of image.
SLO 2016
First Nikon
microscope
(around year 1900)
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Objective quality is crucial. Its basic parameters are:
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NA (numerical aperture) – describes the acceptance cone (its lightgathering ability).
Refractive index and acceptance cone
NA  n  sin 

Resolution - depends on NA and 
d min  0.61

NA
4
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Transmission and refleflective microscope – different samples need
different types of ilumination
First Nikon
microscope
(around year 1900)
SLO 2016
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BRIGHTFIELD
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PHASE CONTRAST
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Uses oblique illumination. Objective catches
only light which direction was altered by sample
Contrast of contours and small structural details
POLARIZED LIGHT
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SLO 2016
Uses special 3 zone mask for oblique
illumination to enhance contrast of optical
phase gradient.
„poor man´s DIC“ 
DARK FIELD
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Using of Wollaston prisms and crossed
polarizators allows interference of points on
sample that are closer than dmin.
exaggerate small gradients differences in
optical path (thickness, refractive index).
HOFFMAN MODULATION
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Translate phase shifts of light into intensity
change.
Interference of undifracted (iluminating) and
difracted (through sample) light.
Ideal for unstead samples (like cells on glass).
DIFFERENCIAL INTERFERENCE
CONTRAST (NOMARSKI)
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Oldest technique: direct lightning; Contrast
relies on differences in light absorption, n, or
color .
Using of cross-polarization elements to strongly
enhance birefringent materials

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Marvin Minsky, 1957
Common use of LCSM – late 80s
Principle:
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A narrow laser beam passes through aperture and highNA objective on sample. Laser is focused nearly to point
with diameter of diffraction limit
Reflected light then returns through the objective to
detector.
Detector (CCD)
Pinhole
Objective
Sample
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Laser
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Light is filtered using pinhole so only the light
from the focus plane passes
Detector (CCD)
Pinhole
only SHARP IMAGE or DARK
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Image is not created at once but point by point
Laser beam is swept by mirrors
Optical slice in the x-y plane
Precisely defined displacement in z-axis
◦ 3D reconstruction images created by composition of
images
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Objective
Sample
Laser
Advantages:

Higher resolution than optical
microscope
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Higher magnification

Depth of field? - Arbitrary –
only focused part are shown….
but in whole user selected
range

3D reconstruction of surface

precise and accurate measurement
SLO 2016
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LEXT
is
laser
scanning
confocal
microscope from Olympus.
Resonance sensor with galvanic mirror fast and accurate image rendering in wide
area.
Maximum magnification 120x - 2400x
or 14400x with „optical zoom“
Laser source – confocal mode
Halogen lamp – classic microsopy
(brightfield)
POSSIBILITY TO MAKE COMBINED
IMAGING
2D and 3D acurate surface reconstruction
in real color
SLO 2016
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2D - intensity or height
image
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3D – intensity, height texture,
wire model, contour
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b-w image, pseudocolors,
true colors
SLO 2016
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Distance/Area Measurement
- two point distance, dX, dY, dZ
- size of the area
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Step measurement
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Scratch test
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Change of topic
dimension
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Reflector and refractor
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objective with long focal
distance and ocular/eyepiece
with short one
For imaging of far objects under
larger viewing angle, and gather
more light from the object than
the naked eye
  f obj / f oc
SLO 2016
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The largest cosmic ray observatory in the world
Hybrid cosmic-rays detector
Particle energies more than tens EeV
Fluorescence detectors
- 7 buildings, with 27 optical telescopes in total
Cherenkov detectors
- 1600 barrels with 12 tons of pure water
and three photomultipliers, in the 1.5 km grid
Malargüe,
Province
Mendoza,
ARGENTINA
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3 000 km2

The incident ultra energetic particle induce the cascade
of secondary particles
◦ Barrels catch the secondary particles that survive and hit the
ground
◦ Fluorescence flash from the secondary particles flyby through the
atmosphere is displayed FD mirrors on the photodetector array
SLO 2016

The incident ultra energetic particle induce the cascade
of secondary particles
◦ Barrels catch the secondary particles that survive and hit the
ground
◦ Fluorescence flash from the secondary particles flyby through the
atmosphere is displayed FD mirrors on the photodetector array
SLO 2016
Fluorescence telescope
- Mirror radius of curvature R = 3400 mm
- The curvature of PMT camera Rc = 1742 mm
- Field of wiev= 30° x 30°
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Fluorescence telescope
( model + realization)
Product of
Joint laboratory of
optics in Olomouc
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• Glass: PIREX
• Thickness: 15 mm
• Radius of curvature: 3406±6 mm
• Reflective layer: Aluminium + protective layer SiO2
FAST
Fluorescence detector Array of Singlepixel Telescopes
SLO 2016
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Mirror segment from Pierre Auger and Cherenkov Telescope array,
as well as any other optical coatings must have good mechanical
properties
◦ Resistance against wear
◦ Good adhesion to substrate
◦ Strong cohesive forces in coating itself
Surface
coating
Interlayer
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substrate
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This type of testing we are capable to perform in JLoO using
NANOINDENTATION and NANOSCRATCH TEST, which are
among other evaluated by our laser scanning confocal microscope.
Method and samples will be shown on the excursion in laboratories.
Thank you for your
attention
SLO 2016
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