VLE 2 Optical Instruments I
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Mirror telescope
Eye
Eye-
piece Intermedia te image
Astronomy: mirror telescopes
Concave mirrors can be manufactured in bigger diameters → more light
Diameter up to 10 m
Virtual image in infinite distance
source: Demtröder, Experimentalphysik 2
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Prof. M. Schmidt
Institute of Photonic Technologies, Univ. Erlangen, Germany
Modern telescope (1)
source: http://de.wikipedia.org/wiki/Large_Binocular_Telescope
source: http://de.wikipedia.org/wiki/Gran_Telescopio_Canarias
Top:
Large Binocular Telescope (LBT) with two 8.4 m diameter mirrors built on top of Mount Graham (Arizona), 3267 m over sea-level
Left:
Gran Telescopio Canarias (GTC) built on top of Roque de los Muchachos (Kanaren) with 10.4 m mirrors
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Prof. M. Schmidt
Institute of Photonic Technologies, Univ. Erlangen, Germany
Modern telescope (2)
Paranal-Observatorium with the Very Large Telescope (VLT) in Chile 2635 m over sea level. It consists of 4 telescopes with mirror diameters of 8.2 m which can be linked together
source: http://de.wikipedia.org/wiki/Very_Large_Telescope
Hubble Space Telescope with a mirror diameter of 2.4 m.
source: http://de.wikipedia.org/wiki/Hubble-Weltraumteleskop
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Prof. M. Schmidt
Institute of Photonic Technologies, Univ. Erlangen, Germany
4. Projector
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Prof. M. Schmidt
Institute of Photonic Technologies, Univ. Erlangen, Germany
Basic principle, diascope
Lamp Diapositiv
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Screen |
Mirror |
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Condenser |
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Objective |
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source: Eichler, Physikalisches Grundpraktikum |
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Projector: Image of a transparent objective (diapositiv) with a projection objective. The image is highly magnified on the screen
Combined illumination and imaging light path
Homogenous illumination: Image of the lamp by the condenser in the objective
Generation of a real inverted (flipped) image.
source: http://leifi.physik.uni-muenchen.de/web_ph09 /zusatzaufgaben/12linsen/projektor/projektor.htm
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Prof. M. Schmidt
Institute of Photonic Technologies, Univ. Erlangen, Germany
Projector: DLP-Projektor
Colour wheel:
Function
DMD
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source: www.cine4home.de |
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source: http://focus.ti.com/pdfs/dlpdmd/DMD-101.pdf |
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DLP-Projektor: Image of a reflectiong object (Digital-Light- |
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Processorbzw. Digital-Micromirror-Device-Chip) on the |
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screen |
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Similar optical path as in previous projector |
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DLP: contains DMD and controls DMD. function: bi |
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stable tilt of 2 Mio. Mirrors with 20…30 KHz |
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→ intensity control |
source: www.heise.de |
Colour wheel: about 200 Hz spinning frequency, for |
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generation of a colour image; synchronize with DLP- |
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chip |
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Prof. M. Schmidt |
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Institute of Photonic Technologies, Univ. Erlangen, Germany |
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Projector: LCD-projector
LCD-projector: Image from three LCD‘s (Liquid Crystal Display) on the screen
Splitting of the light in red /green/blue with dichroitic mirrors
For all three colours: similar optical path as previous setups
Instead of slide→ LCD controllable transmissive b/w display
Mixing of the three colours with a prism
source: www.nitto-optical.co.jp
Advantage: no moving parts, for mixing colours with fast motions like the DLP
Disadvantage: complex setup, with longer usage the different colour images shift to each other
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Prof. M. Schmidt
Institute of Photonic Technologies, Univ. Erlangen, Germany
5. Camera
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Prof. M. Schmidt
Institute of Photonic Technologies, Univ. Erlangen, Germany
Pinhole camera
source: http://de.wikipedia.org/wiki/Lochkamera
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Prof. M. Schmidt
Institute of Photonic Technologies, Univ. Erlangen, Germany
Basic principle
Transparent screen
source: Demtröder, Experimentalphysik 2
Image: P → elliptical disc around P‘
Image the more sharp the smaller d
No focussing –> usage of a low amount of light rays
Problem: intensity und diffraction limited
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Prof. M. Schmidt
Institute of Photonic Technologies, Univ. Erlangen, Germany