Holography. Mario Chemnitz

Transcription

1 Holography Mario Chemnitz Talk in the context of the seminar of Laser Physics Physikalisch-Astronomische Fakultät Friedrich-Schiller-Universität Jena 16 th June 2009

2 Table of contents 1 Motivation 2 Theoretical Basics Basic Principle of Holography Types of holograms 3 Thin Holograms Experimental Conditions Holograms of different kinds of objects 4 Thick Holograms Principle of volumetric / white-light holograms Application example 5 Summary Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

3 Table of contents 1 Motivation 2 Theoretical Basics Basic Principle of Holography Types of holograms 3 Thin Holograms Experimental Conditions Holograms of different kinds of objects 4 Thick Holograms Principle of volumetric / white-light holograms Application example 5 Summary Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

4 Begriffsklärung What is Holography? Definition: Holography As Holography (greek holos: complete, graphein: record) is called the recording (and reproduction) of a 3dim. optical wave with its complete amplitude and phase information on a 2dim. plane using the ability of interference of two or more coherent waves. Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

5 Begriffsklärung What is Holography? Definition: Holography As Holography (greek holos: complete, graphein: record) is called the recording (and reproduction) of a 3dim. optical wave with its complete amplitude and phase information on a 2dim. plane using the ability of interference of two or more coherent waves. Historical Key Data In 1948 Dennis Gábor developed the principle of holography based on interference of object and reference wave. Until the developement of the Laser in 1960 (by Theodore Maiman) holography was less interesting. In 1971 Dennis Gábor got the Nobel Prize for his idea. Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

6 Begriffsklärung Why Holographie? Existing Applications Murals with 3D-effect Originality seals Digital Holography (simulation of diffraction pattern etc.) First holographic data storage: e.g. 300GB on a DVD-sized HoloDisk (Jan Bayer Info ) Material stress control using hologram interferometry Info Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

7 Begriffsklärung Why Holographie? Theoretical Applications Fast, high capacitive storage media: a few TB on a 1cm 3 single crystal with access rates til 1GB/s 3D visualizing color screens (volumetric displays) Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

8 Table of contents 1 Motivation 2 Theoretical Basics Basic Principle of Holography Types of holograms 3 Thin Holograms Experimental Conditions Holograms of different kinds of objects 4 Thick Holograms Principle of volumetric / white-light holograms Application example 5 Summary Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

9 Basic Principle of Holography Recording of holograms (off-axis) Interference of signal and reference wave S = S 0 e i(kz ωt) e iφ S(x,y) i(kzz+ky y ωt) R = R 0 e Hologramm I Objekt S R Abbildung: Scheme of recording holograms Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

10 Basic Principle of Holography Recording of holograms (off-axis) Interference of signal and reference wave S = S 0 e i(kz ωt) e iφ S(x,y) i(kzz+ky y ωt) R = R 0 e Intensity on the medium 2 cε 0 I = S + R 2 = R 2 + S 2 + SR + S R = I R + I S + +SR + S R Objekt Hologramm I S R Abbildung: Scheme of recording holograms Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

11 Basic Principle of Holography Recording of holograms (off-axis) Interference of signal and reference wave S = S 0 e i(kz ωt) e iφ S(x,y) i(kzz+ky y ωt) R = R 0 e Intensity on the medium 2 cε 0 I = S + R 2 = R 2 + S 2 + SR + S R = I R + I S + +SR + S R Transmission of the medium T = T 0 +τi T 0,τ = const. Objekt Hologramm I S R Abbildung: Scheme of recording holograms Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

12 Basic Principle of Holography Reproduction of holograms (off-axis) Diffraction of the reference wave R (here R = R) at the interference pattern S = R T Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

13 Basic Principle of Holography Reproduction of holograms (off-axis) Diffraction of the reference wave R (here R = R) at the interference pattern S = R T = (T 0 +τi R )R +τri }{{}}{{} S 0 th order halo +τs R 2 }{{} signal wave +τs R 2 }{{} c.c. wave Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

14 Basic Principle of Holography Reproduction of holograms (off-axis) Diffraction of the reference wave R (here R = R) at the interference pattern S = R T = (T 0 +τi R )R +τri }{{}}{{} S 0 th order halo +τs R 2 }{{} signal wave +τs R 2 }{{} c.c. wave Virtuelles Bild ϕ S 0. Halo ϕ S Beobachter R Abbildung: Scheme of reproduction of holograms Info Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

15 Basic Principle of Holography More exact consideration of the transmitted field ϕ ϕ S 0. Halo S R Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

16 Basic Principle of Holography More exact consideration of the transmitted field Zeroth order i(kzz+ky y ωt) U 0 = (T 0 +τi R ) R 0 e ϕ ϕ S 0. Halo S R Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

17 Basic Principle of Holography More exact consideration of the transmitted field Zeroth order i(kzz+ky y ωt) U 0 = (T 0 +τi R ) R 0 e Halo S 0. U0 H =τi S R 0 e i(kz z+kyy ωt) ϕ Halo ϕ S R Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

18 Basic Principle of Holography More exact consideration of the transmitted field Zeroth order i(kzz+ky y ωt) U 0 = (T 0 +τi R ) R 0 e Halo U H 0 i(kz z+kyy ωt) =τi S R 0 e Reconstructed signal wave ϕ ϕ S 0. Halo S U 1 =τ R 0 2 S 0 e i(kz ωt) e iφ S(x,y) R Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

19 Basic Principle of Holography More exact consideration of the transmitted field Zeroth order i(kzz+ky y ωt) U 0 = (T 0 +τi R ) R 0 e Halo U H 0 i(kz z+kyy ωt) =τi S R 0 e Reconstructed signal wave ϕ ϕ S 0. Halo S U 1 =τ R 0 2 S 0 e i(kz ωt) e iφ S(x,y) Complex conjugated wave R U 1 =τs 0 R2 0 ei((2kz k)z+2ky y ωt) e iφ S(x,y) Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

20 Types of holograms Classification of holograms Transmission and reflexion holograms Differentiation, wether object is observable in transmitted or reflected light Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

21 Types of holograms Classification of holograms Transmission and reflexion holograms Differentiation, wether object is observable in transmitted or reflected light Amplitude and phase holograms Differentiation by kind of modulation of the reference signal Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

22 Types of holograms Classification of holograms Transmission and reflexion holograms Differentiation, wether object is observable in transmitted or reflected light Amplitude and phase holograms Differentiation by kind of modulation of the reference signal Thick and thin holograms Differentiation by thickness d of storage layer compared to the written average grid constant ā d ā thin d ā thick Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

23 Table of contents 1 Motivation 2 Theoretical Basics Basic Principle of Holography Types of holograms 3 Thin Holograms Experimental Conditions Holograms of different kinds of objects 4 Thick Holograms Principle of volumetric / white-light holograms Application example 5 Summary Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

24 Experimental Conditions Requirements Light source: intensive, coherent In the following experiment: HeNe-Laser: temporal coherence checked using Michelson-Interferometer coherence length has to be kept Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

25 Experimental Conditions Requirements Light source: intensive, coherent In the following experiment: HeNe-Laser: temporal coherence checked using Michelson-Interferometer coherence length has to be kept Storage medium: High resolution, high sensibility, simple handling In the following experiment: Photographic plate (photo-sensible emulsion) Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

26 Experimental Conditions Requirements Light source: intensive, coherent In the following experiment: HeNe-Laser: temporal coherence checked using Michelson-Interferometer coherence length has to be kept Storage medium: High resolution, high sensibility, simple handling In the following experiment: Photographic plate (photo-sensible emulsion) Examples for storage media: Medium Rewriteable Resolution Sensibility [ mm ] [ mj cm ] 2 1 Photo-sensible No emulsion Photorefractive Yes crystal CCD Yes Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

27 Holograms of different kinds of objects Optical assembly for recording and reproduction (a) Laser ST O RF α α 45 o (b) Laser RF VB α B FP FP Laser ST RF Laser RF α α 45 o O FP VB FP B Abbildung: (a) Recording and (b) reproduction of holograms of reflective (top) and transparent (bottom) objects; ST - beam splitter, RF - spatial filter, FP - photographic plate, O - object, VB - virtual image, B - observer Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

28 Holograms of different kinds of objects Transparent objects Abbildung: Glass spheres in different focus planes of a camera; left hand: photography; right hand: hologram Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

29 Holograms of different kinds of objects Reflecting objects Abbildung: White porcelain-angel; left hand: photography; right hand: hologram (recording time: 5 ) Abbildung: Colored Super-Mario-Figure; left hand: photography; right hand: hologram (recording time: 1 45 ) Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

30 Table of contents 1 Motivation 2 Theoretical Basics Basic Principle of Holography Types of holograms 3 Thin Holograms Experimental Conditions Holograms of different kinds of objects 4 Thick Holograms Principle of volumetric / white-light holograms Application example 5 Summary Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

31 Principle of volumetric / white-light holograms Principle of volumetric / white-light holograms (a) Recording: Writting of a interference pattern along the depth of the storage medium (a) (b) (c) E R,λ E H E R E S E R E1 E2 a ε ε a E H Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

32 Principle of volumetric / white-light holograms Principle of volumetric / white-light holograms (a) Recording: Writting of a interference pattern along the depth of the storage medium (b) Reproduction: Irradiation with mono- or polychromatic Light (a) (b) (c) E R,λ E H E R E S E R E1 E2 a ε ε a E H Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

33 Principle of volumetric / white-light holograms Principle of volumetric / white-light holograms (a) Recording: Writting of a interference pattern along the depth of the storage medium (b) Reproduction: Irradiation with mono- or polychromatic Light (c) For the visibility of holograms (constructive spatial interference) the Bragg-condition has to be fullfilled E 1 + E 2 : φ =φ 2 φ 1 = 2a sinε. = mλ (a) (b) (c) E R,λ E H E R E S E R E1 E2 a ε ε a E H Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

34 Application example Optical assembly Laser RF O FP Abbildung: Schematic set-up for recording of white-light holograms of reflective objects; RF - spatial filter, FP - photographic plate, O - object Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

35 Application example Volumetric holograms of a Two-Euro-Coin Abbildung: Back site of a Two-Euro-Coin; left hand: photography; right hand: hologram Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

36 Application example Volumetric holograms of a Two-Euro-Coin Abbildung: Back site of a Two-Euro-Coin; left hand: photography; right hand: hologram Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

37 Application example Volumetric holograms of a Two-Euro-Coin Abbildung: Back site of a Two-Euro-Coin; left hand: photography; right hand: hologram Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

38 Application example Volumetric holograms of a Two-Euro-Coin Abbildung: Back site of a Two-Euro-Coin; left hand: photography; right hand: hologram Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

39 Application example Volumetric holograms of a Two-Euro-Coin Abbildung: Back site of a Two-Euro-Coin; left hand: photography; right hand: hologram Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

40 Application example Volumetric holograms of a Two-Euro-Coin Abbildung: Back site of a Two-Euro-Coin; left hand: photography; right hand: hologram Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

41 Application example Volumetric holograms of a Two-Euro-Coin Abbildung: Back site of a Two-Euro-Coin; left hand: photography; right hand: hologram Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

42 Application example Volumetric holograms of a Two-Euro-Coin Abbildung: Back site of a Two-Euro-Coin; left hand: photography; right hand: hologram Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

43 Application example Volumetric holograms of a Two-Euro-Coin Abbildung: Back site of a Two-Euro-Coin; left hand: photography; right hand: hologram Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

44 Application example Volumetric holograms of a Two-Euro-Coin Abbildung: Back site of a Two-Euro-Coin; left hand: photography; right hand: hologram Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

45 Application example Volumetric holograms of a Two-Euro-Coin Abbildung: Back site of a Two-Euro-Coin; left hand: photography; right hand: hologram Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

46 Application example Volumetric holograms of a Two-Euro-Coin Abbildung: Back site of a Two-Euro-Coin; left hand: photography; right hand: hologram Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

47 Application example Volumetric holograms of a Two-Euro-Coin Abbildung: Back site of a Two-Euro-Coin; left hand: photography; right hand: hologram Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

48 Table of contents 1 Motivation 2 Theoretical Basics Basic Principle of Holography Types of holograms 3 Thin Holograms Experimental Conditions Holograms of different kinds of objects 4 Thick Holograms Principle of volumetric / white-light holograms Application example 5 Summary Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

49 Summary Holography: Storage of the complete phase information of a 3D optical field on a 2D medium using interference with a reference wave Minimum condition for recording holograms: intensive coherent light source (z.b. LASER), high resolution storage medium (z.b. photographic plate) Prinziple: Recording: Interference of a monochromatic signal and reference wave I = S + R 2 Reproduction: Diffraction of a monochrom. reference wave by the interference grating several wave parts: reconstructed signal (virtual) + further parts (0 th order, Halo, c.c. signal (real)) Prinziple of thick holograms: Recording: Writing of a subsurface structure Reproduction: Polychrom. light Bragg-condition: 2a sinε. = mλ constructive interference reconstructed signal Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

50 Literature D. Meschede: Optik, Licht und Laser 3. revised edition; Vierweg+Teubner Verlag; 2008 Wiesbaden. J. Eichler, G. Ackermann: Holographie Springer Verlag; 1993 Berlin Heidelberg NewYork London Paris Tokyo H. Kiemle, D. Röss: Einführung in die Technik der Holographie Akademische Verlagsgesellschaft; 1969 Frankfurt am Main Notes of the lecture Optische Informationsspeicherung und -verarbeitung read at FSU Jena by Prof. Kowarschik, Dr. Kiesling Instructions of advanced partical course of University Jena to the experiment Holographie Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

51 Image sources 1 c -frei 2 Mit freundlicher Genehmigung von Fotograph Hans-Ulrich Pötsch 3 Öffentliche Gallerie - c -frei Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

52 Thanks to your attention!

53 The future Abbildung: Schematic picture of RW-access for several storage media: A: DVD, B: BlueRay-Disc, C: HoloDisk; figure by Bayer webreport Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

54 Hologram interferometry Recording: Partial recording of the unstressed object ( intensity I), then partial recording of the stressed object ( intensity I ) both on the same photographic plate I ges = I + I = 2 R 2 + S 2 + S 2 + R (S + S ) + R(S + S }{{} ) }{{} virtuell reell Reproduction: Irradiation of the medium with the reference wave I virt (S + S )(S + S ) S 2 + S S S cos(φ S φ S) Result: characteristical line pattern, which gives answers about the stress influence of the object Abbildung: Hologram (right handed) of a white shield (left handed) under simulated stress Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27

55 The written photo-plate Abbildung: Two microscopic exposure with 400times magnification of a lighted up photo-/hologram-plate Mario Chemnitz (PAF - FSU Jena) Holography 16 th June / 27